Question: What is (are) Pneumonia ?
Answer: Pneumonia (nu-MO-ne-ah) is an infection in one or both of the lungs. Many germssuch as bacteria, viruses, and fungican cause pneumonia. The infection inflames your lungs' air sacs, which are called alveoli (al-VEE-uhl-eye). The air sacs may fill up with fluid or pus, causing symptoms such as a cough with phlegm (a slimy substance), fever, chills, and trouble breathing. Overview Pneumonia and its symptoms can vary from mild to severe. Many factors affect how serious pneumonia is, such as the type of germ causing the infection and your age and overall health. Pneumonia tends to be more serious for: Infants and young children. Older adults (people 65 years or older). People who have other health problems, such as heart failure, diabetes, or COPD (chronic obstructive pulmonary disease). People who have weak immune systems as a result of diseases or other factors. Examples of these diseases and factors include HIV/AIDS, chemotherapy (a treatment for cancer), and an organ transplant or blood and marrow stem cell transplant. Outlook Pneumonia is common in the United States. Treatment for pneumonia depends on its cause, how severe your symptoms are, and your age and overall health. Many people can be treated at home, often with oral antibiotics. Children usually start to feel better in 1 to 2 days. For adults, it usually takes 2 to 3 days. Anyone who has worsening symptoms should see a doctor. People who have severe symptoms or underlying health problems may need treatment in a hospital. It may take 3 weeks or more before they can go back to their normal routines. Fatigue (tiredness) from pneumonia can last for a month or more.
Source: NHLBI

Question: What causes Pneumonia ?
Answer: Many germs can cause pneumonia. Examples include different kinds of bacteria, viruses, and, less often, fungi. Most of the time, the body filters germs out of the air that we breathe to protect the lungs from infection. Your immune system, the shape of your nose and throat, your ability to cough, and fine, hair-like structures called cilia (SIL-e-ah) help stop the germs from reaching your lungs. (For more information, go to the Diseases and Conditions Index How the Lungs Work article.) Sometimes, though, germs manage to enter the lungs and cause infections. This is more likely to occur if: Your immune system is weak A germ is very strong Your body fails to filter germs out of the air that you breathe For example, if you can't cough because you've had a stroke or are sedated, germs may remain in your airways. ("Sedated" means you're given medicine to make you sleepy.) When germs reach your lungs, your immune system goes into action. It sends many kinds of cells to attack the germs. These cells cause the alveoli (air sacs) to become red and inflamed and to fill up with fluid and pus. This causes the symptoms of pneumonia. Germs That Can Cause Pneumonia Bacteria Bacteria are the most common cause of pneumonia in adults. Some people, especially the elderly and those who are disabled, may get bacterial pneumonia after having the flu or even a common cold. Many types of bacteria can cause pneumonia. Bacterial pneumonia can occur on its own or develop after you've had a cold or the flu. This type of pneumonia often affects one lobe, or area, of a lung. When this happens, the condition is called lobar pneumonia. The most common cause of pneumonia in the United States is the bacterium Streptococcus (strep-to-KOK-us) pneumoniae, or pneumococcus (nu-mo-KOK-us). Lobar Pneumonia Another type of bacterial pneumonia is called atypical pneumonia. Atypical pneumonia includes: Legionella pneumophila. This type of pneumonia sometimes is called Legionnaire's disease, and it has caused serious outbreaks. Outbreaks have been linked to exposure to cooling towers, whirlpool spas, and decorative fountains. Mycoplasma pneumonia. This is a common type of pneumonia that usually affects people younger than 40 years old. People who live or work in crowded places like schools, homeless shelters, and prisons are at higher risk for this type of pneumonia. It's usually mild and responds well to treatment with antibiotics. However, mycoplasma pneumonia can be very serious. It may be associated with a skin rash and hemolysis (the breakdown of red blood cells). Chlamydophila pneumoniae. This type of pneumonia can occur all year and often is mild. The infection is most common in people 65 to 79 years old. Viruses Respiratory viruses cause up to one-third of the pneumonia cases in the United States each year. These viruses are the most common cause of pneumonia in children younger than 5 years old. Most cases of viral pneumonia are mild. They get better in about 1 to 3 weeks without treatment. Some cases are more serious and may require treatment in a hospital. If you have viral pneumonia, you run the risk of getting bacterial pneumonia as well. The flu virus is the most common cause of viral pneumonia in adults. Other viruses that cause pneumonia include respiratory syncytial virus, rhinovirus, herpes simplex virus, severe acute respiratory syndrome (SARS), and more. Fungi Three types of fungi in the soil in some parts of the United States can cause pneumonia. These fungi are: Coccidioidomycosis (kok-sid-e-OY-do-mi-KO-sis). This fungus is found in Southern California and the desert Southwest. Histoplasmosis (HIS-to-plaz-MO-sis). This fungus is found in the Ohio and Mississippi River Valleys. Cryptococcus (krip-to-KOK-us). This fungus is found throughout the United States in bird droppings and soil contaminated with bird droppings. Most people exposed to these fungi don't get sick, but some do and require treatment. Serious fungal infections are most common in people who have weak immune systems due to the long-term use of medicines to suppress their immune systems or having HIV/AIDS. Pneumocystis jiroveci (nu-mo-SIS-tis ye-RO-VECH-e), formerly Pneumocystis carinii, sometimes is considered a fungal pneumonia. However, it's not treated with the usual antifungal medicines. This type of infection is most common in people who: Have HIV/AIDS or cancer Have had an organ transplant and/or blood and marrow stem cell transplant Take medicines that affect their immune systems Other kinds of fungal infections also can lead to pneumonia.
Source: NHLBI

Question: Who is at risk for Pneumonia? ?
Answer: Pneumonia can affect people of all ages. However, two age groups are at greater risk of developing pneumonia: Infants who are 2 years old or younger (because their immune systems are still developing during the first few years of life) People who are 65 years old or older Other conditions and factors also raise your risk for pneumonia. You're more likely to get pneumonia if you have a lung disease or other serious disease. Examples include cystic fibrosis, asthma, COPD (chronic obstructive pulmonary disease), bronchiectasis, diabetes, heart failure, and sickle cell anemia. You're at greater risk for pneumonia if you're in a hospital intensive-care unit, especially if you're on a ventilator (a machine that helps you breathe). Having a weak or suppressed immune system also raises your risk for pneumonia. A weak immune system may be the result of a disease such as HIV/AIDS. A suppressed immune system may be due to an organ transplant or blood and marrow stem cell transplant, chemotherapy (a treatment for cancer), or long-term steroid use. Your risk for pneumonia also increases if you have trouble coughing because of a stroke or problems swallowing. You're also at higher risk if you can't move around much or are sedated (given medicine to make you relaxed or sleepy). Smoking cigarettes, abusing alcohol, or being undernourished also raises your risk for pneumonia. Your risk also goes up if you've recently had a cold or the flu, or if you're exposed to certain chemicals, pollutants, or toxic fumes.
Source: NHLBI

Question: What are the symptoms of Pneumonia ?
Answer: The signs and symptoms of pneumonia vary from mild to severe. Many factors affect how serious pneumonia is, including the type of germ causing the infection and your age and overall health. (For more information, go to "Who Is at Risk for Pneumonia?") See your doctor promptly if you: Have a high fever Have shaking chills Have a cough with phlegm (a slimy substance), which doesn't improve or worsens Develop shortness of breath with normal daily activities Have chest pain when you breathe or cough Feel suddenly worse after a cold or the flu People who have pneumonia may have other symptoms, including nausea (feeling sick to the stomach), vomiting, and diarrhea. Symptoms may vary in certain populations. Newborns and infants may not show any signs of the infection. Or, they may vomit, have a fever and cough, or appear restless, sick, or tired and without energy. Older adults and people who have serious illnesses or weak immune systems may have fewer and milder symptoms. They may even have a lower than normal temperature. If they already have a lung disease, it may get worse. Older adults who have pneumonia sometimes have sudden changes in mental awareness. Complications of Pneumonia Often, people who have pneumonia can be successfully treated and not have complications. But some people, especially those in high-risk groups, may have complications such as: Bacteremia (bak-ter-E-me-ah). This serious complication occurs if the infection moves into your bloodstream. From there, it can quickly spread to other organs, including your brain. Lung abscesses. An abscess occurs if pus forms in a cavity in the lung. An abscess usually is treated with antibiotics. Sometimes surgery or drainage with a needle is needed to remove the pus. Pleural effusion. Pneumonia may cause fluid to build up in the pleural space. This is a very thin space between two layers of tissue that line the lungs and the chest cavity. Pneumonia can cause the fluid to become infecteda condition called empyema (em-pi-E-ma). If this happens, you may need to have the fluid drained through a chest tube or removed with surgery.
Source: NHLBI

Question: How to diagnose Pneumonia ?
Answer: Pneumonia can be hard to diagnose because it may seem like a cold or the flu. You may not realize it's more serious until it lasts longer than these other conditions. Your doctor will diagnose pneumonia based on your medical history, a physical exam, and test results. Medical History Your doctor will ask about your signs and symptoms and how and when they began. To find out what type of germ is causing the pneumonia, he or she also may ask about: Any recent traveling you've done Your hobbies Your exposure to animals Your exposure to sick people at home, school, or work Your past and current medical conditions, and whether any have gotten worse recently Any medicines you take Whether you smoke Whether you've had flu or pneumonia vaccinations Physical Exam Your doctor will listen to your lungs with a stethoscope. If you have pneumonia, your lungs may make crackling, bubbling, and rumbling sounds when you inhale. Your doctor also may hear wheezing. Your doctor may find it hard to hear sounds of breathing in some areas of your chest. Diagnostic Tests If your doctor thinks you have pneumonia, he or she may recommend one or more of the following tests. Chest X Ray A chest x ray is a painless test that creates pictures of the structures inside your chest, such as your heart, lungs, and blood vessels. A chest x ray is the best test for diagnosing pneumonia. However, this test won't tell your doctor what kind of germ is causing the pneumonia. Blood Tests Blood tests involve taking a sample of blood from a vein in your body. A complete blood count (CBC) measures many parts of your blood, including the number of white blood cells in the blood sample. The number of white blood cells can show whether you have a bacterial infection. Your doctor also may recommend a blood culture to find out whether the infection has spread to your bloodstream. This test is used to detect germs in the bloodstream. A blood culture may show which germ caused the infection. If so, your doctor can decide how to treat the infection. Other Tests Your doctor may recommend other tests if you're in the hospital, have serious symptoms, are older, or have other health problems. Sputum test. Your doctor may look at a sample of sputum (spit) collected from you after a deep cough. This may help your doctor find out what germ is causing your pneumonia. Then, he or she can plan treatment. Chest computed tomography (CT) scan. A chest CT scan is a painless test that creates precise pictures of the structures in your chest, such as your lungs. A chest CT scan is a type of x ray, but its pictures show more detail than those of a standard chest xray. Pleural fluid culture. For this test, a fluid sample is taken from the pleural space (a thin space between two layers of tissue that line the lungs and chest cavity). Doctors use a procedure called thoracentesis (THOR-ah-sen-TE-sis) to collect the fluid sample. The fluid is studied for germs that may cause pneumonia. Pulse oximetry. For this test, a small sensor is attached to your finger or ear. The sensor uses light to estimate how much oxygen is in your blood. Pneumonia can keep your lungs from moving enough oxygen into your bloodstream. If you're very sick, your doctor may need to measure the level of oxygen in your blood using a blood sample. The sample is taken from an artery, usually in your wrist. This test is called an arterial blood gas test. Bronchoscopy. Bronchoscopy (bron-KOS-ko-pee) is a procedure used to look inside the lungs' airways. If you're in the hospital and treatment with antibiotics isn't working well, your doctor may use this procedure. Your doctor passes a thin, flexible tube through your nose or mouth, down your throat, and into the airways. The tube has a light and small camera that allow your doctor to see your windpipe and airways and take pictures. Your doctor can see whether something is blocking your airways or whether another factor is contributing to your pneumonia.
Source: NHLBI

Question: What are the treatments for Pneumonia ?
Answer: Treatment for pneumonia depends on the type of pneumonia you have and how severe it is. Most people who have community-acquired pneumoniathe most common type of pneumoniaare treated at home. The goals of treatment are to cure the infection and prevent complications. General Treatment If you have pneumonia, follow your treatment plan, take all medicines as prescribed, and get ongoing medical care. Ask your doctor when you should schedule followup care. Your doctor may want you to have a chest x ray to make sure the pneumonia is gone. Although you may start feeling better after a few days or weeks, fatigue (tiredness) can persist for up to a month or more. People who are treated in the hospital may need at least 3 weeks before they can go back to their normal routines. Bacterial Pneumonia Bacterial pneumonia is treated with medicines called antibiotics. You should take antibiotics as your doctor prescribes. You may start to feel better before you finish the medicine, but you should continue taking it as prescribed. If you stop too soon, the pneumonia may come back. Most people begin to improve after 1 to 3 days of antibiotic treatment. This means that they should feel better and have fewer symptoms, such as cough and fever. Viral Pneumonia Antibiotics don't work when the cause of pneumonia is a virus. If you have viral pneumonia, your doctor may prescribe an antiviral medicine to treat it. Viral pneumonia usually improves in 1 to 3 weeks. Treating Severe Symptoms You may need to be treated in a hospital if: Your symptoms are severe You're at risk for complications because of other health problems If the level of oxygen in your bloodstream is low, you may receive oxygen therapy. If you have bacterial pneumonia, your doctor may give you antibiotics through an intravenous (IV) line inserted into a vein.
Source: NHLBI