Impetigo - National Library of Medicine - PubMed Health About the Skin About Impetigo Impetigo (Impetigo contagiosa) is an itchy and sometimes painful infection of the outer layers of skin . It is especially common in young children. The infection is caused by bacteria and is very contagious. Children who have it should not go to daycare, kindergarten or school, where they might infect other children. Symptoms The early signs of impetigo usually appear around the mouth and nose : an itchy reddish rash with liquid-filled blisters that burst very easily. The burst blisters form yellowish crusts, which then later fall off without leaving behind any scars . Causes and risk factors Impetigo is a bacterial infection , usually caused by Streptococcus or Staphylococcus bacteria . These germs can enter your skin in different ways, including through minor cuts or scrapes, a rash or an insect bite. They spread to other people through skin contact, or through contact with objects that an infected person has touched... Read more about Impetigo What works?

Research summarized Impetigo: Causes, Symptoms, and Treatments - Medical News Today Impetigo: Causes, Symptoms, and Treatments Written by Christian NordqvistReviewed by University of Illinois-Chicago, School of Medicine 3.5 18 Impetigo (also called Infantigo) is a highly contagious skin infection that most commonly affects children. In northern Europe, northern America, and Canada, impetigo is the most common bacterial skin infection in children. The first sign of impetigo is a patch of red, itchy skin. Children aged 2-5 years are the most likely to develop impetigo. However, people of all ages can be affected. Impetigo is more common where people live in confined environments, such as army barracks, or in warm, humid climates. Impetigo is rarely serious and usually resolves on its own within a couple of weeks. However, doctors may decide to treat children with an antibiotic ointment or oral antibiotics to prevent complications, which may sometimes occur. Contents of this article: Fast facts on impetigo Here are some key points about impetigo. More detail and supporting information is in the main article.

Impetigo is an extremely contagious skin infection; it is most common in children Impetigo is caused by Staphylococcus aureus or Streptococcus pyogenes bacteria It is the most common childhood bacterial skin infection in northern Europe, northern USA, and Canada Treatment will depend on the type of impetigo and the severity of symptoms Symptoms of impetigo There are two main types of impetigo: Non-bullous impetigo (Impetigo contagiosa) Impetigo is most often caused caused by Staphylococcus aureus. Red sores appear around the mouth and nose, (occasionally they start in the extremities). The sores soon burst and ooze either fluid or pus, leaving thick, yellowish-brownish golden crusts. As the crusts dry, they leave a red mark which usually heals without any scarring. Although the sores are not painful, they may itch a great deal. It is important not to touch or scratch them so that the infection does not spread to other parts of the body and other people. In rare cases, symptoms may be more severe, and the patient may have a fever and swollen glands.

Non-bullous impetigo (Impetigo contagiosa) - accounts for approximately 70 percent of all cases Bullous impetigo Bullous impetigo mainly affects babies and children under the age of 2. Medium to large-sized fluid-filled blisters appear on the trunk, legs, and arms. The skin around the blister is red and itchy, but not sore. They often spread rapidly and eventually burst, leaving a yellow crust. The crust normally heals with no scarring. Although the blisters are not painful, they may itch a lot. Patients must try not to touch or scratch them. Fever and swollen glands are common in patients with bullous impetigo. This type of impetigo is caused by a certain strain of Staphylococcus aureus that secretes a type of toxin that targets the skin layer. Causes of impetigo Impetigo is caused by two types of bacteria : Staphylococcus aureus Streptococcus pyogenes Both types of bacteria exist harmlessly on human skin. They cause infection when there is a cut or wound.

Impetigo in adults is usually the result of injury to the skin - commonly by another skin condition, such as dermatitis (inflammation of the skin). Children are usually infected after a cut, scrape, or insect bite. However, children may also become infected without any apparent skin damage. One person can become infected by touching things that an infected person has been in contact with, such as bed linen, towels, toys, and clothing. Once infected, that person can easily pass it on to other people. Staphylococcus aureus produces a toxin that causes impetigo to spread to nearby skin. The toxin attacks a protein that helps keep skin cells bound together. As soon as this protein is damaged, the bacteria can spread rapidly. There are two ways the infection can start: Primary impetigo - bacteria invade the skin through a cut, insect bite, or other lesion on normal skin Secondary impetigo - bacteria invade the skin because another skin infection or condition has disrupted the skin barrier, such as eczema or scabies Symptoms do not appear until 4 to 10 days after initial exposure to the bacteria. During those days, people often pass the infection on to others because they do not know they are infected.

Experts say children are more likely to become infected and show symptoms because their immune systems are not yet fully developed. Impetigo diagnosis Secondary impetigo can occur when bacteria invade the skin after another infection or condition has disrupted the skin barrier. Impetigo is fairly easy to diagnose by examining the affected area. The doctor will probably ask the patient (or parent) about any recent cuts, scrapes, or insect bites to the affected area. The doctor will also try to find out whether it has appeared on top of another skin condition, such as scabies . Further tests may be ordered if: Symptoms are very severe and have spread to many parts of the body The patient does not respond to treatment The infection keeps recurring The doctor will gently wipe a crusted area with a swab to see which germ is causing the impetigo and which antibiotic is most likely to work. A swab may also help determine whether another infection is present, like ringworm or shingles. If the patient has repeated episodes of impetigo, the doctor may take a swab from the nose to determine whether the infective bacteria are based there.

Treatments for impetigo The aim of treatment is to speed up healing, improve the skin's appearance, and prevent complications and the spread of infection. Treatment will depend on the type of impetigo and the severity of symptoms. Mild infections A doctor may just opt for hygienic measures; this means keeping the skin clean. Topical antibiotics Antibiotics are applied directly onto the skin. The doctor might prescribe mupirocin ointment (Bactroban). Before applying ointment, scabs need to be gently removed so that the antibiotic can get deep into the skin. It is important to wash affected areas of skin with warm, soapy water before applying a topical antibiotic. If possible, latex gloves should be used when applying the cream; hands should be washed thoroughly afterward. The patient should respond to treatment within 7 days. Oral antibiotics These are prescribed when the impetigo is more widespread or if the patient has not responded to topical antibiotics. The type of antibiotic depends on the severity and infection, as well as other factors, including the patient's medical condition and whether they have any allergies. A course of antibiotics usually lasts about 7 days. It is important to complete the course, even if symptoms clear up early.

A child can go back to school 24 hours after antibiotic treatment started, or when the sores have crusted and healed. Complications of impetigo Although complications with impetigo are rare, they can be serious. On the very rare occasions that complications do occur , they can be serious. Any parent who sees worsening symptoms in their child should tell their doctor straight away. Cellulitis - when the infection goes into a deeper layer of skin, cellulitis can occur, causing symptoms including red, inflamed skin, fever, and pain. Guttate psoriasis - a type of psoriasis characterized by red, scaly patches of inflamed skin on all parts of the body. It is non-infectious and may occur in children and teenagers after a bacterial infection, especially a throat infection. Scarlet fever - a rare bacterial infection caused by Streptococcus pyogenes and characterized by a fine pink rash across the body. The patient may also have nausea, vomiting, and pain. Bacteremia or sepsis - a bacterial infection of the blood. The patient will have a fever, possibly rapid breathing and vomiting, confusion, and dizziness. This is a life-threatening infection and requires immediate hospitalization.

Post-streptococcal glomerulonephritis - an infection of the small blood vessels in the kidneys that can be fatal for adults. This complication of impetigo is very rare. Symptoms include darkened colored urine and hypertension. Patients will usually have to be hospitalized so that their blood pressure can be monitored. Prevention of impetigo Good hygiene is the best way to reduce the risk of developing or spreading impetigo. Cuts, scrapes, grazes, and insect bites should be washed immediately and kept clean. If somebody has impetigo, it is important to keep their belongings isolated from other people and to follow strict hygiene measures.

The following will help prevent the spread of infection to others, and also to other parts of the patient's body: Wash the affected areas with a neutral soap and running water Then cover the area lightly with gauze Do not touch the sores and encourage the patient not to touch the sores The patient's clothes, bedding, towels, and other toiletries should be washed daily The patient's clothes must not be shared or worn by other people When applying antibiotic ointment, gloves should be worn, washing hands thoroughly afterward Keep the patient's nails short to reduce scratching Wash hands and the patient's hands often Isolate the patient until they are not contagious To prevent a recurrence of impetigo, make sure any skin condition, such as eczema , is treated properly. Written by Christian Nordqvist Click the stars to rate this article Impetigo: Causes, Symptoms, and Treatments Public / Patient Impetigo Impetigo Impétigo Impi-what? Impetigo (say: im-pih-TIE-go) is a strange-sounding word that may be new to you. It's an infection of the skin caused by bacteria.

Impetigo is commonly found on the face, often around the nose and mouth, but it can show up anywhere the skin has been broken. If you have a cut or scrape or if you scratch your skin because of a bug bite , eczema , or poison ivy , germs may find a way to get inside. Once inside, the bacteria cause small blisters to develop on the skin. These blisters burst and ooze fluid that crusts over, a condition called impetigo. Kids seem to get it more than adults do, but impetigo can affect anyone. What Causes Impetigo? We all have bacteria living on our skin and in our nose, but most of the time they don't cause any trouble. Two types of bacteria can cause impetigo: group A streptococcus (say strep-toe-KAH-kus) and Staphylococcus aureus (say: stah-fih-lo-KAH-kus OR-ee-us). It doesn't matter which bacteria cause someone's impetigo — the treatment is almost the same. How Do I Know if I Have It? Impetigo usually starts as small blisters that burst and ooze fluid that crusts over.

The crust is yellow-brown, or honey-colored, making impetigo look different from other scabs. The other kind of impetigo affects babies and younger kids more than older kids. In this type, the blisters are larger and take longer to burst. The fluid in these blisters may start out clear and then turn cloudy. continue What Will the Doctor Do? If you and your parents think you have impetigo, you should see a doctor . A doctor usually can tell if you have impetigo by examining your skin. If you have mild impetigo, your doctor probably will prescribe an antibiotic ointment, which gets put right on your skin. An antibiotic is a type of medicine that attacks bacteria. If the impetigo has spread to a few places or if the antibiotic ointment is not working, you may need to take an antibiotic pill or liquid for about 10 days. Remember: It's important to finish ALL of the medicine even if the spots clear up quickly. What Can I Do? Impetigo might itch, but try not to scratch or touch the sores. Touching them can spread the sores to other parts of your body or to someone else.

If you do touch the area, be sure to wash your hands right away. Your mom or dad can help you apply the ointment or take the medicine your doctor prescribed. Your parent also can help you gently wash the infected areas with mild soap and water, using a piece of clean gauze. If a sore is very crusted, you can soak it in warm, soapy water to loosen the crust. You don't have to get it all off, but it's good to keep it clean. Your parent also might help you cover the sores with gauze and tape or a loose plastic bandage. Impetigo is contagious, which means that you could spread it to other people. That's why people with impetigo should keep the sores covered when they go to school or other public places. After you take the medicine for least 24 hours, the impetigo isn't contagious anymore. After 3 days, the sores should begin to heal. Your mom or dad should call the doctor if you develop a fever or if you don't get better after taking the medicine for a few days.

Your parent should call the doctor right away if skin around the impetigo sore becomes red, warm, swollen, or painful if you touch it. previous continue How to Prevent Impetigo If someone in your family or a friend has impetigo, don't touch that person's skin. Also steer clear of his or her clothes, towels, sheets, and pillows. The bacteria that cause impetigo can live on all these things. Your parent should wash these items in very hot water. And here are some good habits that can help you avoid getting impetigo in the first place: Take a bath or shower regularly. Use soap to keep your skin clean. Watch out for skin that's scraped or irritated, like a mosquito bite. Keep those areas clean and covered and don't scratch. Wash your hands regularly with soap. Keep your nails short and clean. Impi-what? Now you know — it's impetigo! Scabies Scabies Sarna What Is Scabies? Scabies (pronounced: SKAY-beez) is a common skin infestation of tiny mites called Sarcoptes scabiei.

The mites burrow into the top layer of human skin to lay their eggs, causing small itchy bumps and blisters. Someone with scabies might notice a bumpy red rash. Occasionally, raised wavy lines where the mites have burrowed may appear, especially on the inner part of the wrist or between the fingers or toes. How Do People Get Scabies? Scabies is contagious from person to person, and anyone can get it. The mites don't care if you're clean, dirty, rich, or poor. All they want is to live on or in the skin of a human being, and any human being will do. Scabies mites (so tiny they need a microscope to be seen) usually spread through skin-to-skin contact (especially among family members). Mites also can live for about 2 to 3 days in clothing, bedding, or dust, making it possible for scabies to spread among people who share the same infected bed, linens, or towels. Scabies spreads more easily in crowded conditions — like within a household, childcare centers, and college dorms — where people tend to be in close contact with each other. Scabies also can be sexually transmitted.

It may take up to 4 to 6 weeks after infection for symptoms to appear in a person who's never had scabies before. In people who have had scabies previously, symptoms may appear in just a few days. What Are the Signs and Symptoms? The most common symptom of scabies is severe itching, which may be worse at night or after a hot bath. A scabies infection begins as small, itchy bumps, blisters, or pus-filled bumps that break when you scratch them. Itchy skin may become thick, scaly, scabbed, and crisscrossed with scratch marks. The itching is due to a reaction of your body to the mite and/or its feces (poop) and eggs. The areas of the body most commonly affected by scabies are the hands and feet (especially the webs of skin between the fingers and toes), the inner part of the wrists, and the folds under the arms. It may also affect other areas of the body, particularly the elbows and the areas around the breasts, genitals, navel, and buttocks. If a person with scabies scratches the itchy areas of skin, it increases the chance that the injured skin will also be infected by bacteria.

Impetigo , a bacterial skin infection, may occur in skin that already has scabies. continue How Do Doctors Treat Scabies? Scabies infections need to be treated by a doctor. Call your doctor or dermatologist any time you have a skin itch that will not go away, especially if the itch is worse at night and seems to center around the wrists or the webbed part of the fingers. If your doctor suspects you have scabies, he or she may scrape a small part of the affected skin and examine the scrapings under a microscope for signs of scabies mites. Doctors treat scabies by prescribing a medicated cream or lotion. The cream will need to be applied all over the body (except the face, eyes, and mouth), and usually must remain on the skin for 8 to 12 hours before it can be washed off. Make sure to also trim your fingernails. Scrape off any debris or dirt from your fingertips, and put medicine on the fingertips as well. After applying the cream, don't wash your hands — scabies mites love the area between the fingers! Most often, the treatment needs to be repeated in 1 week.

Because scabies can be sexually transmitted, sexually active teens with scabies should be examined for other sexually transmitted diseases (STDs) , too. Any sexual partners also will need to be treated for scabies. Since scabies is highly contagious and can cause re-infestations, the other members of your household also should be treated for scabies, even if they have no symptoms. If you develop a bacterial skin infection (such as impetigo) in addition to the scabies infection, your doctor may prescribe antibiotics and, to treat itching, antihistamines. Sometimes itching can last for a few weeks even if a person no longer has scabies. If you still have a lot of itching after the infection has cleared, your doctor may prescribe a steroid skin cream like hydrocortisone. A steroid cream should be used only if recommended by your doctor because certain infections can become worse with its use. You can return to school or work the day after the treatment is finished. Can I Avoid Getting Scabies? Direct physical contact is the most common way to get scabies. It's also possible to get scabies from infected linens and clothing since scabies can live for 2 to 3 days away from human skin.

So while it can be tempting, try not to share clothing with friends. If someone in your family is being treated for scabies, all other household members should be treated, too. Wash clothing, sheets, and towels in hot water and dry on a hot setting. Put stuffed animals and other items that cannot be washed in a sealed plastic bag for at least 3 days. Vacuum each room in the house, then throw away the vacuum cleaner bag. Impetigo Causes, Symptoms, Treatments, Prevention Credits What is impetigo? Impetigo (say "im-puh-TY-go") is a bacterial skin infection. It causes red sores that can break open, ooze fluid, and develop a yellow-brown crust. These sores can occur anywhere on the body. Impetigo is one of the most common skin infections in children. It can occur in adults but is seen far more often in children. Impetigo is contagious and can be spread to others through close contact or by sharing towels, sheets, clothing, toys, or other items. Scratching can also spread the sores to other parts of the body. What causes impetigo?

Impetigo is caused by one of two kinds of bacteria-strep ( streptococcus ) or staph (staphylococcus). Often these bacteria enter the body when the skin has already been irritated or injured because of other skin problems such as eczema , poison ivy , insect bites , burns, or cuts. Children may get impetigo after they have had a cold or allergies that have made the skin under the nose raw. But impetigo can also develop in completely healthy skin . What are the symptoms? You or your child may have impetigo if you have sores: That begin as small red spots, then change to blisters that eventually break open. The sores are typically not painful, but they may be itchy. That ooze fluid and look crusty. That increase in size and number. Sores may be as small as a pimple or larger than a coin. How is impetigo diagnosed? Your doctor can usually diagnose impetigo just by looking at your or your child's skin . Sometimes your doctor will gently remove a small piece of a sore to send to a lab to identify the bacteria. If you or your child has other signs of illness, your doctor may order blood or urine tests.

How is it treated? Impetigo is treated with antibiotics . For cases of mild impetigo, a doctor will prescribe an antibiotic ointment or cream to put on the sores. For cases of more serious impetigo, a doctor may also prescribe antibiotic pills. A child can usually return to school or daycare after 24 hours of treatment. If you apply the ointment or take the pills exactly as prescribed, most sores will be completely healed in 1 week. Continued At home, gently wash the sores with clean water each day. If crusts form, your doctor may advise you to soften or remove the crusts. You can do this by soaking them in warm water and patting them dry. This can help the cream or ointment work better. After you touch the area, wash your hands with soap and water or use an alcohol-based hand sanitizer. Try not to scratch the sores, because scratching can spread the infection to other parts of the body. You can help prevent scratching by keeping your child's fingernails short. You can cover the sores with a loose bandage. The sores need air to heal.

Call your doctor if you do not get better as expected or if you notice any signs that the infection is getting worse, such as fever, increased pain, swelling, warmth, redness, or pus. How can impetigo be prevented? If you know someone who has impetigo, try to avoid close contact with that person until his or her infection has gone away. Do not share towels, sheets, or clothes until the infection is gone. Wash anything that may have touched the infected area. If you or your child has impetigo, scratching the sores can spread the infection to other areas of your body and to other people. Wash your or your child's hands with soap to help prevent spreading the infection. WebMD Medical Reference from Healthwise This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.© 1995-2015 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated. Pagination Diseases and Disorders of the Skin (Integumentary System) 1.

Congenital Skin Conditions Eczema A common skin condition characterized by reddening (erythema) and vesicle formation, which may lead to weeping and crusting. It is endogenous, or 'constitutional'. This means that outside agents do not play a primary role. (Contrast this with dermatitis , in which case outside agents DO play a primary role.) However in some contexts the terms 'dermatitis' and 'eczema' are used interchangeably to refer to the symptoms of these skin conditions. There are five main types of eczema : Atopic Eczema, which is associated with asthma and hay fever . Seborrhoeic Eczema (or Dermatitis), typically affecting the scalp, eyelids, nose, and lips. this is associated with the presence of Pityrosporum yeasts and is common among AIDS patients. Discoid (or Nummular) Eczema, characterized by coin-shaped lesions and only occuring in adults. Pompholyx, affecting only the hands and feet. Gravitational (or Stasis) Eczema, associated with poor venous circulation (sometimes referred to as 'Varicose Eczema').

Psoriasis A chronic skin disease in which scaly pink patches form on the elbows, knees, scalp, and other parts of the body. Psorisis is one of the commonest skin diseases in Britain, affecting about 2% of the population (cause unknown). This disorder often runs in families, the commonest time of onset being in adolesence. It sometimes occurs in association with arthritis. Occasionally the disease may be very severe, affecting much of the skin and causing considerable disability in the patient. While psychological stress might make psorisis worse, the only significant event thought to precipitate this condition is a preceeding streptococcal infection. Dermatitis An inflammatory condition of the skin caused by outside agents. (Contrast this with eczema, an endogenous disease in which outside agents do NOT play a primary role). Primary irritant dermatitis may occur in anyone who has sufficient contact with irritants such as acids, alkalis, solvents and (especially) detergents. Primary irritant dermatitis is the commonest cause of occupational dermatitis in hairdressers, nurses, cooks etc..

In the case of allergic contact dermatitis skin changes resembling those of eczema develop as a delayed reaction to contact with a particular allergen which might only have been present at low concentrations. The commonest example of allergic contact dermatitis in women is nickel dermatitis due to the metal nickel used in jewellery, jeans studs etc, whereas In men chromium dermatitis is relatively common. Treatment of dermatitis depends on removing the cause, which is not always possible. Dermititis herpetiformis is an uncommon very itchy rash with symmetrical blistering, especially on the knees, elbows, buttocks and shoulders. It is related to sensitivity to gluten. 2. Bacterial Skin Conditions Acne vulgaris A common inflammatory condition of the sebaceous glands. These grease-producing glands are under androgen control, but the cause of acne is unknown. It involves the face, back and chest and is characterized by the presence of blackheads with papules, pustules - and in more severe cases - cysts and scars. Impetigo Causes, Contagious, Transmission, Complications What Is Impetigo? What Is Impetigo? Impetigo is a highly contagious bacterial skin infection. It can appear anywhere on the body but usually attacks exposed areas.

Children tend to get it on the face, especially around the nose and mouth , and sometimes on the arms or legs. The infected areas appear in plaques ranging from dime to quarter size, starting as tiny blisters that break and expose moist, red skin. After a few days, the infected area is covered with a grainy, golden crust that gradually spreads at the edges. In extreme cases, the infection invades a deeper layer of skin and develops into ecthyma, a deeper form of the disease. Ecthyma forms small, pus-filled bumps with a crust much darker and thicker than that of ordinary impetigo . Ecthyma can be very itchy, and scratching the irritated area spreads the infection quickly. Left untreated, the sores may cause permanent scars and pigment changes. The gravest potential complication of impetigo is post-streptococcal glomerulonephritis, a severe kidney disease that occurs following a strep infection in less than 1% of cases, mainly in children. The most common cause of impetigo is Staphylococcus aureus. However, another bacteria source is group A streptococcus . These bacteria lurk everywhere.

It is easier for a child with an open wound or fresh scratch to contract impetigo. Other skin-related problems, such as eczema , body lice , insect bites , fungal infections, and various other forms of dermatitis can make a person susceptible to impetigo. Most people get this highly infectious disease through physical contact with someone who has it or from sharing the same clothes, bedding, towels, or other objects. The very nature of childhood, which includes lots of physical contact and large-group activities, makes children the primary victims and carriers of impetigo. WebMD Medical Reference Reviewed by Stephanie S. Gardner, MD on April 15, 2015 Sources Human Physiology/Integumentary System - Wikibooks, open books for an open world Human Physiology/Integumentary System Introduction[ edit ] The integumentary system consists of the skin, hair, nails, the subcutaneous tissue below the skin,and assorted glands.The most obvious function of the integumentary system is the protection that the skin gives to underlying tissues. The skin not only keeps most harmful substances out, but also prevents the loss of fluids.

A major function of the subcutaneous tissue is to connect the skin to underlying tissues such as muscles. Hair on the scalp provides insulation from cold for the head. The hair of eyelashes and eyebrows helps keep dust and perspiration out of the eyes, and the hair in our nostrils helps keep dust out of the nasal cavities. Any other hair on our bodies no longer serves a function, but is an evolutionary remnant. Nails protect the tips of fingers and toes from mechanical injury. Fingernails give the fingers greater ability to pick up small objects. There are four types of glands in the integumentary system: Sudoriferous glands, Sebaceous glands, Ceruminous glands, and Mammary glands. Sudoriferous glands are sweat producing glands. These are important to help maintain body temperature. Sebaceous glands are oil producing glands which help inhibit bacteria, keep us waterproof and prevent our hair and skin from drying out. Ceruminous glands produce earwax which keeps the outer surface of the eardrum pliable and prevents drying. Mammary glands produce milk.

Skin[ edit ] In zoology and dermatology, skin is an organ of the integumentary system made up of a layer of tissues that guard underlying muscles and organs. As the interface with the surroundings, it plays the most important role in protecting against pathogens. Its other main functions are insulation and temperature regulation, sensation and vitamin D and B synthesis. Skin is considered one of the most important parts of the body. Skin has pigmentation, melanin, provided by melanocytes, which absorbs some of the potentially dangerous radiation in sunlight. It also contains DNA repair enzymes which reverse UV damage, and people who lack the genes for these enzymes suffer high rates of skin cancer. One form predominantly produced by UV light, malignant melanoma, is particularly invasive, causing it to spread quickly, and can often be deadly. Human skin pigmentation varies among populations in a striking manner. This has sometimes led to the classification of people(s) on the basis of skin color. Damaged skin will try to heal by forming scar tissue, often giving rise to discoloration and depigmentation of the skin. The skin is often known as "the largest organ in the human body".

This applies to exterior surface, as it covers the body, appearing to have the largest surface area of all the organs. Moreover, it applies to weight, as it weighs more than any single internal organ, accounting for about 15 percent of body weight. For the average adult human, the skin has a surface area of between 1.5-2.0 square meters, most of it is between 2-3 mm thick. The average square inch of skin holds 650 sweat glands, 20 blood vessels, 60,000 melanocytes, and more than a thousand nerve endings. The use of natural or synthetic cosmetics to treat the appearance of the face and condition of the skin (such as pore control and black head cleansing) is common among many cultures. Layers[ edit ] The skin has two major layers which are made of different tissues and have very different functions. Diagram of the layers of human skin Skin is composed of the epidermis and the dermis. Below these layers lies the hypodermis or subcutaneous adipose layer, which is not usually classified as a layer of skin. The outermost epidermis consists of stratified squamous keratinizing epithelium with an underlying basement membrane.

It contains no blood vessels, and is nourished by diffusion from the dermis. The main type of cells which make up the epidermis are keratinocytes, with melanocytes and Langerhans cells also present. The epidermis can be further subdivided into the following strata (beginning with the outermost layer): corneum, lucidum, granulosum, spinosum, basale. Cells are formed through mitosis at the innermost layers. They move up the strata changing shape and composition as they differentiate, inducing expression of new types of keratin genes. They eventually reach the corneum and become sloughed off (desquamation). This process is called keratinization and takes place within about 30 days. This layer of skin is responsible for keeping water in the body and keeping other harmful chemicals and pathogens out. Blood capillaries are found beneath the dermis, and are linked to an arteriole and a venule. Arterial shunt vessels may bypass the network in ears, the nose and fingertips. The dermis lies below the epidermis and contains a number of structures including blood vessels, nerves, hair follicles, smooth muscle, glands and lymphatic tissue.

It consists of loose connective tissue otherwise called areolar connective tissue - collagen, elastin and reticular fibers are present. Erector muscles, attached between the hair papilla and epidermis, can contract, resulting in the hair fiber pulled upright and consequentially goose bumps. The main cell types are fibroblasts, adipocytes (fat storage) and macrophages. Sebaceous glands are exocrine glands which produce, a mixture of lipids and waxy substances: lubrication, water-proofing, softening and antibactericidal actions are among the many functions of sebum. Sweat glands open up via a duct onto the skin by a pore. The dermis is made of an irregular type of fibrous connective tissue consisting of collagen and elastin fibers. It can be split into the papillary and reticular layers. The papillary layer is outermost and extends into the epidermis to supply it with vessels. It is composed of loosely arranged fibers. Papillary ridges make up the lines of the hands giving us fingerprints. The reticular layer is more dense and is continuous with the hypodermis. It contains the bulk of the structures (such as sweat glands).

The reticular layer is composed of irregularly arranged fibers and resists stretching. The hypodermis is not part of the skin, and lies below the dermis. Its purpose is to attach the skin to underlying bone and muscle as well as supplying it with blood vessels and nerves. It consists of loose connective tissue and elastin. The main cell types are fibroblasts, macrophages and adipocytes (the hypodermis contains 95% of body fat). Fat serves as padding and insulation for the body. Clinical Application: The patch drug delivery system. The transdermal patch is an increasingly popular drug delivery system. These patches are designed so that the drug molecules diffuse through the epidermis to the blood vessels in the dermis layer. A typical patch works well for small lipid-soluble molecules (for example, estrogen, nitroglycerin, and nicotine) that can make their way between epidermal cells.

Functions[ edit ] Protection: Skin gives an anatomical barrier between the internal and external environment in bodily defense; Langerhans cells in the skin are part of the immune system Sensation: Skin contains a variety of nerve endings that react to heat, cold, touch, pressure, vibration, and tissue injury; see somatosensory system and touch . Heat regulation: The skin contains a blood supply far greater than its requirements which allows precise control of energy loss by radiation, convection and conduction. Dilated blood vessels increase perfusion and heat loss while constricted vessels greatly reduce cutaneous blood flow and conserve heat. Erector pili muscles are significant in animals. Wikipedia has related information at Hair Types of hair[ edit ] Humans have three different types of hair: Lanugo, the fine, unpigmented hair that covers nearly the entire body of a fetus, although most has been replaced with vellus by the time of the baby's birth Vellus hair, the short, downy, "peach fuzz" body hair (also unpigmented) that grows in most places on the human body.

While it occurs in both sexes, and makes up much of the hair in children, men have a much smaller percentage (around 10%) vellus whereas 2/3 of a female's hair is vellus. Terminal hair, the fully developed hair, which is generally longer, coarser, thicker, and darker than vellus hair, and often is found in regions such as the axillary, male beard, and pubic. Pathological impacts on hair[ edit ] Drugs used in cancer chemotherapy frequently cause a temporary loss of hair, noticeable on the head and eyebrows, because they kill all rapidly dividing cells, not just the cancerous ones. Other diseases and traumas can cause temporary or permanent loss of hair, either generally or in patches. The hair shafts may also store certain poisons for years, even decades, after death. In the case of Col. Lafayette Baker, who died July 3, 1868, use of an atomic absorption spectrophotometer showed the man was killed by white arsenic. The prime suspect was Wallace Pollock, Baker's brother-in-law. According to Dr. Ray A.

Neff, Pollack had laced Baker's beer with it over a period of months, and a century or so later minute traces of arsenic showed up in the dead man's hair. Mrs. Baker's diary seems to confirm that it was indeed arsenic, as she writes of how she found some vials of it inside her brother's suit coat one day. Parts of the fingernail[ edit ] The parts of a finger nail The fingernail is an important structure made of keratin. The fingernail generally serve two purposes. It serves as a protective plate and enhances sensation of the fingertip. The protection function of the fingernail is commonly known, but the sensation function is equally important. The fingertip has many nerve endings in it allowing us to receive volumes of information about objects we touch. The nail acts as a counterforce to the fingertip providing even more sensory input when an object is touched. Nail Structure[ edit ] The structure we know of as the nail is divided into six specific parts - the root, nail bed, nail plate, eponychium (cuticle), perionychium, and hyponychium. Root The root of the fingernail is also known as the germinal matrix.

This portion of the nail is actually beneath the skin behind the fingernail and extends several millimeters into the finger. The fingernail root produces most of the volume of the nail and the nail bed. This portion of the nail does not have any melanocytes, or melanin producing cells. The edge of the germinal matrix is seen as a white, crescent shaped structure called the lunula. Nail Bed The nail bed is part of the nail matrix called the sterile matrix. It extends from the edge of the germinal matrix, or lunula, to the hyponychium. The nail bed contains the blood vessels, nerves, and melanocytes, or melanin-producing cells. As the nail is produced by the root, it streams down along the nail bed, which adds material to the undersurface of the nail making it thicker. It is important for normal nail growth that the nail bed be smooth. If it is not, the nail may split or develop grooves that can be cosmetically unappealing. Nail Plate The nail plate is the actual fingernail, made of translucent keratin. The pink appearance of the nail comes from the blood vessels underneath the nail.

The underneath surface of the nail plate has grooves along the length of the nail that help anchor it to the nail bed. eponychium The cuticle of the fingernail is also called the eponychium. The cuticle is situated between the skin of the finger and the nail plate fusing these structures together and providing a waterproof barrier. Perionychium The perioncyhium is the skin that overlies the nail plate on its sides. It is also known as the paronychial edge. The perionychium is the site of hangnails, ingrown nails, and an infection of the skin called paronychia. Hyponychium The hyponychium is the area between the nail plate and the fingertip. It is the junction between the free edge of the nail and the skin of the fingertip, also providing a waterproof barrier. Nails: left hand, adult human male Nail Diseases[ edit ] Nail diseases are in a separate category from diseases of the skin. Although nails are a skin appendage, they have their own signs and symptoms which may relate to other medical conditions. Nail conditions that show signs of infection or inflammation require medical assistance and cannot be treated at a beauty parlor.

Deformity or disease of the nails may be referred to as onychosis. There are many disease that can occur with the fingernails and toenails. The most common of these diseases are ingrown nails and fungal infections. Ingrown Nails[ edit ] Onychocryptosis, commonly known as "ingrown nails" (unguis incarnatus), can affect either the fingers or the toes. In this condition, the nail cuts into one or both sides of the nail bed, resulting in inflammation and possibly infection. The relative rarity of this condition in the fingers suggests that pressure from the ground or shoe against the toe is a prime factor. The movements involved in walking or other physical disturbances can contribute to the problem. Mild onychocryptosis, particularly in the absence of infection, can be treated by trimming and rounding the nail. More advanced cases, which usually include infection, are treated by surgically excising the ingrowing portion of the nail down to its bony origin and cauterizing the matrix, or 'root', to prevent recurrence. This surgery is called matricectomy. The best results are achieved by cauterizing the matrix with phenol.

Another method, which is much less effective, is excision of the matrix, sometimes called a 'cold steel procedure' Nail Fungus[ edit ] An infection of nail fungus (onychomycosis) occurs when fungi infect one or more of your nails. Onychomycosis generally begins as a white or yellow spot under the tip of the fingernail or toenail. As the nail fungus spreads deeper into the nail, it may cause the nail to discolor, thicken and develop crumbling edges — an unsightly and potentially painful problem. Infections of nail fungus account for about half of all nail disorders. These infections usually develop on nails continually exposed to warm, moist environments, such as sweaty shoes or shower floors. Nail fungus isn't the same as athlete's foot, which primarily affects the skin of the feet, but at times the two may coexist and can be caused by the same type of fungus. An infection with nail fungus may be difficult to treat, and infections may recur. But medications are available to help clear up nail fungus permanently.

Clinical Application[ edit ] Nail inspection can give a great deal of information about the internal working of the body as well, and like tongue or iris inspection, has a long history of diagnostic use in cantraditional medical practices such as Chinese medicine. Pliability: Brittleness is associated with iron deficiency, thyroid problems, impaired kidney function, circulation problems[2], and biotin deficiency[3] Splitting and fraying are associated with psoriasis, folic acid, protein and/or Vitamin C deficiency. Unusual thickness is associated with circulation problems. Thinning nails and itchy skin are associated with lichen planus[4]. Shape and texture: Clubbing, or nails that curve down around the fingertips with nail beds that bulge is associated with oxygen deprivation and lung, heart, or liver disease. Spooning, or nails that grow upwards is associated with iron or B12 deficiency. Flatness can indicate a B12 vitamin deficiency[5] or Raynaud's disease[6] Pitting of the nails is associated with Psoriasis. Horizontal ridges indicate stress, and Beau's lines are associated with many serious conditions. Vertical ridges are associated with arthritis[7].

Vertical grooves are associated with kidney disorders, aging, and iron deficiency[8]. Beading is associated with rheumatoid arthritis[9]. Nails that resemble hammered brass are associated with (or portend) hair loss[10]. Short small beds are associated with heart disease[11]. Coloration of the nail bed: Mee's lines are associated with arsenic or thallium poisoning, and renal failure. White lines across the nail are associated with heart disease, liver disease, or a history of a recent high fever[12]. Opaque white nails with a dark band at the fingertip are associated with cancer, cirrhosis, congestive heart failure, diabetes and aging[13]. Paleness or whitening is associated with liver or kidney disease and anemia[14]. Yellowing of the nail bed is associated with chronic bronchitis, lymphatic problems, diabetes, and liver disorders. Brown or copper nail beds are associated with arsenic or copper poisoning, and local fungal infection. Grey nail beds are associated with arthritis, edema, malnutrition, post-operative effects, glaucoma and cardio-pulmonary disease[15]. redness is associated with heart conditions. dark nails are associated with B12 deficiency.

Stains of the nail plate (not the nail bed) are associated with nail polish[16], smoking, and henna use. Markings: Pink and white nails are associated with kidney disease[17]. Parallel white lines in the nails are associated with hypoalbuminemia. red skin at the base of the nail is associated with connective tissue disorders[18]. blue lunulae are associated with silver poisoning or lung disorder[19]. blue nail beds are (much like blue skin) associated with poor oxygenation of the blood (asthma, emphysema, etc)[20]. small white patches are associated with zinc or calcium deficiency or malabsorption, parasites, or local injury[21]. receded lunulae (fewer than 8) are associated with poor circulation[22], shallow breathing habits or thyroid mysfunction[23]. large lunulae (more than 25% of the thumb nail) is associated with high blood pressure. Sweat Glands[ edit ] A diagrammatic sectional view of the skin (magnified). Sweat gland labeled as "sudoriferous gland" at center right.

In humans, there are two kinds of sweat glands which differ greatly in both the composition of the sweat and its purpose: Also "click" here "How our body Sweats" to see a short movie on sweat glands. Eccrine (a.k.a. merocrine)[ edit ] Eccrine sweat glands are exocrine glands distributed over the entire body surface but are particularly abundant on the palms of hands, soles of feet, and on the forehead. These produce sweat that is composed chiefly of water (99%) with various salts. The primary function is body temperature regulation. Eccrine sweat glands are coiled tubular glands derived leading directly to the most superficial layer of the epidermis (out layer of skin) but extending into the inner layer of the skin (dermis layer). They are distributed over almost the entire surface of the body in humans and many other species, but are lacking in some marine and fur-bearing species. The sweat glands are controlled by sympathetic cholinergic nerves which are controlled by a center in the hypothalamus. The hypothalamus senses core temperature directly, and also has input from temperature receptors in the skin and modifies the sweat output, along with other thermoregulatory processes.

Human eccrine sweat is composed chiefly of water with various salts and organic compounds in solution. It contains minute amounts of fatty materials, urea, and other wastes. The concentration of sodium varies from 35–65 mmol/l and is lower in people acclimatised to a hot environment. The sweat of other species generally differ in composition. Apocrine[ edit ] Apocrine sweat glands only develop during early- to mid-puberty (approximately age 15) and release more than normal amounts of sweat for approximately a month and subsequently regulate and release normal amounts of sweat after a certain period of time. Apocrine sweat glands produce sweat that contains fatty materials. These glands are mainly present in the armpits and around the genital area and their activity is the main cause of sweat odor, due to the bacteria that break down the organic compounds in the sweat from these glands. Emotional stress increases the production of sweat from the apocrine glands, or more precisely: the sweat already present in the tubule is squeezed out. Apocrine sweat glands essentially serve as scent glands. In some areas of the body, these sweat glands are modified to produce wholly different secretions, including the cerumen ("wax") of the outer ear.

Other glands, such as Mammary glands, are greatly enlarged and modified to produce milk. Sebaceous Glands[ edit ] Schematic view of a hair follicle with sebaceous gland. The sebaceous glands are glands found in the skin of mammals. They secrete an oily substance called sebum (Latin, meaning fat or tallow) that is made of fat (lipids) and the debris of dead fat-producing cells. These glands exist in humans throughout the skin except in the palms of the hands and soles of the feet. Sebum acts to protect and waterproof hair and skin, and keep them from becoming dry, brittle, and cracked. It can also inhibit the growth of microorganisms on skin. Sebaceous glands can usually be found in hair-covered areas where they are connected to hair follicles to deposit sebum on the hairs, and bring it to the skin surface along the hair shaft. The structure consisting of hair, hair follicle and sebaceous gland is also known as pilosebaceous unit. Sebaceous glands are also found in non haired areas of lips, eyelids, penis, labia minora and nipples; here the sebum reaches the surface through ducts.

In the glands, sebum is produced within specialized cells and is released as these cells burst; sebaceous glands are thus classified as holocrine glands. Sebum is odorless, but its bacterial breakdown can produce odors. Sebum is the cause of some people experiencing "oily" hair if it is not washed for several days. Earwax is partly sebum, as is mucopurulent discharge, the dry substance accumulating in the corners of the eye after sleeping. A hair follicle with associated structures. The composition of sebum varies from species to species; in humans, the lipid content consists of about 25% wax monoesters, 41% triglycerides, 16% free fatty acids, and 12% squalene. The activity of the sebaceous glands increases during puberty because of heightened levels of androgens. Sebaceous glands are involved in skin problems such as acne and keratosis pilaris. A blocked sebaceous gland can result in a sebaceous cyst. The prescription drug isotretinoin significantly reduces the amount of sebum produced by the sebaceous glands, and is used to treat acne.

The extreme use (up to 10 times doctor prescribed amounts) of anabolic steroids by bodybuilders to prevent weight loss tend to stimulate the sebaceous glands which can cause acne. The sebaceous glands of a human fetus in utero secrete a substance called Vernix caseosa, a "waxy" or "cheesy" white substance coating the skin of newborns. The preputial glands of mice and rats are large modified sebaceous glands that produce pheromones. Ceruminous glands[ edit ] Wet-type human earwax on a cotton swab. Earwax, also known by the medical term cerumen, is a yellowish, waxy substance secreted in the ear canal of humans and many other mammals. It plays a vital role in the human ear canal, assisting in cleaning and lubrication, and also provides some protection from bacteria, fungus, and insects. A comprehensive review of the physiology and pathophysiology of cerumen can be found in Roeser and Ballachanda. Excess or impacted cerumen can press against the eardrum and/or occlude the external auditory canal and impair hearing.

Production, composition, and different types[ edit ] Cerumen is produced in the outer third of the cartilaginous portion of the human ear canal. It is a mixture of viscous secretions from sebaceous glands and less-viscous ones from modified apocrine sweat glands. Two distinct genetically determined types of earwax are distinguished -- the wet-type which is dominant, and the dry type which is recessive. Asians and Native Americans are more likely to have the dry type of cerumen (grey and flaky), whereas Caucasians and Africans are more likely to have the wet type (honey-brown to dark-brown and moist). Cerumen type has been used by anthropologists to track human migratory patterns, such as those of the Inuit. The difference in cerumen type has been tracked to a single base change (an single nucleotide polymorphism) in a gene known as "ATP-binding cassette C11 gene". In addition to affecting cerumen type, this mutation also reduces sweat production. The researchers conjecture that the reduction in sweat was beneficial to the ancestors of East Asians and Native Americans who are thought to have lived in cold climates.

Function[ edit ] Wet-type earwax fluoresces weakly under ultraviolet light. Cleaning. Cleaning of the ear canal occurs as a result of the "conveyor belt" process of epithelial migration, aided by jaw movement. Cells formed in the center of the tympanic membrane migrate outwards from the umbo (at a rate equivalent to that of fingernail growth) to the walls of the ear canal, and accelerate towards the entrance of the ear canal. The cerumen in the canal is also carried outwards, taking with it any dirt, dust, and particulate matter that may have gathered in the canal. Jaw movement assists this process by dislodging debris attached to the walls of the ear canal, increasing the likelihood of its extrusion. Lubrication. Lubrication prevents desiccation and itching of the skin within the ear canal (known as asteatosis). The lubricative properties arise from the high lipid content of the sebum produced by the sebaceous glands. In wet-type cerumen at least, these lipids include cholesterol, squalene, and many long-chain fatty acids and alcohols. Antibacterial and antifungal roles.

While studies conducted up until the 1960s found little evidence supporting an antibacterial role for cerumen, more recent studies have found that cerumen provides some bactericidal protection against some strains of bacteria. Cerumen has been found to be effective in reducing the viability of a wide range of bacteria (sometimes by up to 99%), including Haemophilus influenzae, Staphylococcus aureus, and many variants of Escherichia coli. The growth of two fungi commonly present in otomycosis was also significantly inhibited by human cerumen. These antimicrobial properties are due principally to the presence of saturated fatty acids, lysozyme and, especially, to the relatively low pH of cerumen (typically around 6.1 in normal individuals). Mammary Glands[ edit ] Cross section of the breast of a human female. Mammary glands are the organs that, in the female mammal, produce milk for the sustenance of the young. These exocrine glands are enlarged and modified sweat glands and are the characteristic of mammals which gave the class its name.

Structure[ edit ] The basic components of the mammary gland are the alveoli (hollow cavities, a few millimetres large) lined with milk-secreting epithelial cells and surrounded by myoepithelial cells. These alveoli join up to form groups known as lobules, and each lobule has a lactiferous duct that drains into openings in the nipple. The myoepithelial cells can contract, similar to muscle cells, and thereby push the milk from the alveoli through the lactiferous ducts towards the nipple, where it collects in widenings (sinuses) of the ducts. A suckling baby essentially squeezes the milk out of these sinuses. Dissection of a lactating breast. 1 - Fat 5 - Sinus of lactiferous duct 6 - Lactiferous duct One distinguishes between a simple mammary gland, which consists of all the milk-secreting tissue leading to a single lactiferous duct, and a complex mammary gland, which consists of all the simple mammary glands serving one nipple. Humans normally have two complex mammary glands, one in each breast, and each complex mammary gland consists of 10-20 simple glands.

(The presence of more than two nipples is known as polythelia and the presence of more than two complex mammary glands as polymastia.) Also, "click" this; "Breast tissue" , to this a movie visual of the breast. Development and hormonal control[ edit ] The development of mammary glands is controlled by hormones. The mammary glands exist in both sexes, but they are rudimentary until puberty when in response to ovarian hormones, they begin to develop in the female. Click this [1] to see what breast tissue does in a female during menustration. Estrogen promotes formation, while testosterone inhibits it. At the time of birth, the baby has lactiferous ducts but no alveoli. Little branching occurs before puberty when ovarian estrogens stimulate branching differentiation of the ducts into spherical masses of cells that will become alveoli. True secretory alveoli only develop in pregnancy, where rising levels of estrogen and progesterone cause further branching and differentiation of the duct cells, together with an increase in adipose tissue and a richer blood flow. Colostrum is secreted in late pregnancy and for the first few days after giving birth.

True milk secretion (lactation) begins a few days later due to a reduction in circulating progesterone and the presence of the hormone prolactin. The suckling of the baby causes the release of the hormone oxytocin which stimulates contraction of the myoepithelial cells. Breast cancer[ edit ] As described above, the cells of mammary glands can easily be induced to grow and multiply by hormones. If this growth runs out of control, cancer results. Almost all instances of breast cancer originate in the lobules or ducts of the mammary glands. Types of breast cancer Homeostasis[ edit ] As a whole, the integumentary system plays a big part in maintaining homeostasis. The integumentary system is the outermost organ system of the body and many of its functions are related to this location. The skin protects the body against pathogens and chemicals, minimizes loss or entry of water, and blocks the harmful effects of sunlight. Sensory receptors in the skin provide information about the external environment, helping the skin regulate body temperature in response to environmental changes and helping the body react to pain and other tactile stimuli. The large surface area of the skin makes it ideal for temperature regulation.

The rate of heat loss can be regulated by the amount of blood flowing through the blood vessels in the dermis close to the surface of the skin. When the body temperature rises, as for example during exercise, sympathetic tone is reduced and this brings about dilation of the blood vessels supplying the skin. The increase in skin blood flow allows heat to be lost more rapidly so that body temperature does not rise above the normal homeostatic range. The rate of heat loss can also be boosted by the production of sweat, which takes up additional heat as it evaporates. Conversely, if heat production is less than required, the dermal vessels constrict, sweating stops, and heat is conserved by the body. Glossary[ edit ] Areolar Areolar connective tissue is a pliable, mesh-like tissue with a fluid matrix and functions to cushion and protect body organs. It acts as a packaging tissue holding the internal organs together and in correct placement. Impetigo Symptoms, Treatment, Causes - What are the types of impetigo? What are impetigo symptoms and signs? What does impetigo look like? - MedicineNet Medical Author: John Mersch, MD, FAAP John Mersch, MD, FAAP Dr.

Mersch received his Bachelor of Arts degree from the University of California, San Diego, and prior to entering the University Of Southern California School Of Medicine, was a graduate student (attaining PhD candidate status) in Experimental Pathology at USC. He attended internship and residency at Children's Hospital Los Angeles. Medical Editor: William C. Shiel Jr., MD, FACP, FACR William C. Shiel Jr., MD, FACP, FACR Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology. What are the types of impetigo? What are impetigo symptoms and signs? What does impetigo look like? Share Your Story There are two forms of impetigo: Nonbullous impetigo: This is the more common form, caused by both staph and strep bacteria. This form initially presents as small red papules similar to insect bites.

These lesions rapidly evolve to small blisters and then to pustules that finally scab over with a characteristic honey-colored crust. This entire process usually takes about one week. These lesions often start around the nose and on the face, but less frequently they may also affect the arms and legs. At times, there may be non-tender but swollen lymph nodes (glands) nearby. Bullous impetigo: This form of impetigo is caused only by staph bacteria. These bacteria produce a toxin that reduces cell-to-cell stickiness (adhesion) causing separation between the top skin layer ( epidermis ) and the lower layer (dermis). This leads to the formation of a blister. (The medical term for blister is bulla.) Bullae can appear in various skin areas, especially the buttocks and trunk. These blisters are fragile and contain a clear yellow-colored fluid. The bullae are delicate and often break and leave red, raw skin with a ragged edge. A dark crust will commonly develop during the final stages of development. With healing, this crust will resolve.

Question: Which part of the human body does impetigo affect?
Answer: The skin