Sore throat in children
Synonyms and keywords: Sore throat in kids

# Overview
Sore throat is an infection of the respiratory mucosa of the throat.It is most commonly felt as a sensation of pain in the pharynx. In children it can be classified as acute, subacute or recurrent. Common etiologies include bacterial, Viral and Protozoal organisms. It is usually self resolving, but can be associated with more severe disease forms. Treatment in general is conservative, however Antibiotics and Antivirals can be used depending on the Etiology, and severity of clinical presentation.

# Historical Perspective
- In the year 1879, R. L. Bowles, M.D., described sore throat as 'some variants of sore throat' in the British Medical Journal. 
- Later, in the year 1885, pathology, clinical findings and management were described by David Newman, M.D., at the Glasgow Royal Infirmary.
- In 1910, the importance of laboratory tests was illustrated by Dr. Donelan.
- In 1931, WM. W. PRIDDLE, B.A., M.D., described that certain infections like whooping cough, measles were associated with chronic nasopharyngitis.

# Classification
- Sore throat can be classified into Infectious and Non infectious causes based on the etiology.

## Infectious
- Bacterial:Group A Streptococci,Staphylococcus aureus, Hemophilus influenza, gonococci, chlamydia, Mycoplasma, Treponema   pallidum, Fusobacterium.
- Viral: Adenovirus, Coxsackievirus, Enterovirus, Influenza, Parainfluenza, Epstein Barr Virus, Corona Viruses, Polio Virus, Rhino Virus.
- Protozoal: Babesia microti, Toxoplasma gondii,- less common causes.
- Fungal: Candida.

## Non Infectious
- Autoimmune: Steven Johnson's syndrome, Bechet's disease, Psychotic, Kawasaki's disease, PFAPA syndrome.
- Traumatic: Insertion of a pen, stick, or other sharp object in the throat.
- Chemical exposure : smoking, air pollutants
- Physical factors : snoring, shouting, tracheal intubation

# Pathophysiology
- Prostaglandins and bradykinin act on the sensory nerves in the pharynx, which leads to sore throat.
- Fever is the result of cytokine release and thought to benefit host's response to infection. Cytokines can also cause headache.
- The cranial nerves that supply the nasopharynx are responsible for pain perception.
- Vasodilator mediators like bradykinin causes dilation of the venous sinuses in the nasal epithelium which is responsible for nasal congestion.
- Glandular secretions with different cells (e.g.  neutrophils, plasma cells, goblet cells) and plasma together in different compositions at different times, form nasal discharge.
- Inflammation in the nasopharynx, stimulates the trigeminal nerves, which presents in the form of sneezing.
- The inflammation when reaches the larynx, and stimulates the sensory nerves then coughing is initiated. The inflammatory mediators when act on the sensory nerve endings of the airway cause hyper-reactivity of the cough reflex. 

# Causes
Sore throat in children can be acutely life-threatening or from common causes.

## Bacteria
- Goup A beta-haemolytic Streptococcus (most commonly isolated)
- Haemophilus influenzae
- Moraxella catarrhalis

## Viruses
- Rhinovirus
- Coronavirus
- Respiratory syncytial virus
- Metapneumovirus
- EpsteinBarr virus
- Life threatening causes include: Epiglottitis,retropharygeal abscess, Parapharyngeal abscess, Peritonsillar abscess, Diptheria, Infectious mononucleosis
- other causes include: trauma,psychogenic and autoimmune

# Differentiating Sore throat in children from other Diseases
Sore throat is a symptom and can be seen in many varieties of diseases as an initial complaint of presentation. Clinical history and physical examination can help to distinguish between them.

# Epidemiology and Demographics
One of the most common medical conditions is sore throat, primarily caused by viruses and bacteria. Group A streptococcus(GAS) is the most common causative agent, resposible for 15-25% of cases of pharyngitis in children and 10% in adults. Diagnosis of GAS is important for the treatment and reduction of infectivity. It also prevents post infectious complications. The acute suppurative complications are retropharyngeal and peritonsillar abscess, acute bacterial sinusitis, cervical adenitis and acute otitis media. The late nonsuppurative complications are acute rheumatic fever (ARF) and post-streptococcal glomerulonephritis. In adults, nonsuppurative complications does not need immediate treatment.

# Risk Factors
- The factors which make an individual more susceptible to sore throat are lack of Vaccination, weakened immunity, frequent or chronic sinus infections, age, allergies, chemical irritants or tobacco smoke exposure, close spaces.

# Natural History, Complications and Prognosis
- The majority of patients with Sore throat acquire it as a course of the respiratory tract or oropharyngeal infections and remain asymptomatic for 1-4 days.
- Early clinical features include pain in the throat, itching, discomfort while more severe forms include difficulty swallowing, difficulty breathing.
- These symptoms are usually accompanied by fever, myalgias, arthralgias, rhinorrhea, cough depending on the type of infection.
- Common complications if left untreated in infectious conditions include sinusitis, mastoiditis, otitis media, cervical lymphadenitis, Retropharyngeal abscess, Parapharyngeal abscess, Quinsy, Sepsis.
- The nonsuppurative complications include include acute glomerulonephritis, acute rheumatic fever, reactive arthritis.
- Prognosis is generally excellent and when identified early in acute conditions, minimal to no complications occur. However sore throat is one of the most common complaints and can be relieved by symptomatic treatment if viral. Most of the patients improve spontaneously within 7-10 days.

# Diagnosis

## Diagnostic Criteria
The four important diagnostic criteria, also known as Centor criteria for sore throat are 
- Absent cough and runny nose
- Fever >38 C (100.4 F)
- Tonsillar exudate
- Anterior cervical lymphadenopathy
All 4 criteria present GABHS most likely, no testing required, start empiric antibiotics.
2 or 3- further testing required
0 or 1- further testing or antibiotics not required

## Symptoms
- Sudden onset of sore throat and fever.
- Other symptoms may include:
- Nausea and vomiting, headache, malaise, discomfort in swallowing and abdominal pain.
- Cough, conjunctivitis, nasal congestion and rhinorrhoea are present in viral etiology
- Redness and swelling of tonsils and pharynx are present.
- Tender and enlarged anterior cervical lymph nodes.
- Pharyngeal exudate that can be easily scraped off is present.

## Physical Examination
- Patients with Sore throat usually appear normal in common infections.
- Physical examination may be different depending on the underlying etiology as well as pathology. Examination of the pharynx is the key. However comprehensive examination gives hints for possible etiologies. Notable findings include:
- Exudative Pharyngitis, petechiae on the posterior palate, anterior Cervical lymphadenopathy are seen in streptococcal pharyngitis.
- Thick white exudate with a membranous covering of tonsils, which cannot be removed without bleeding is seen in Diptheria.
- Erythematous Pharynx with posterior cervical lymphadenopathy and hepatosplenomegaly is seen in infectious mononucleosis.
- Vesicular rash on the posterior pharynx is seen in herpangia, and vesicular rash on hand foot, and mouth is seen in hand, foot, and mouth disease. Both are caused by Coxsackie Virus.
- Erythematous pharynx with a diffuse erythematous rash is seen in Scarlet fever.
- Stridor, respiratory distress, dysphagia, odynophagia with high grade fevers can be seen in Quinsy, retropharyngeal abscess, Parapharyngeal abscess, epiglottitis, Laryngotracheobronchitis. Most of these are life threatening. Significant asymmetry of the tonsils should raise suspicion for peritonsillar abscess.
- Vesicles on the buccal mucosa  should raise suspicion for Herpetic Gingivostomatitis. Patients should also be screened for non-infectious causes such as bechet syndrome,Steven Johnson syndrome.
- Inflammed tympanic membrane might suggest a dental abscess. Other possible oropharyngeal pathologies should be ruled out.
- Pernio like lesions in the pharynx is seen in COVID 19 infection.
- If a persistently febrile child demonstrates strawberry tongue, generalized erythema of oropharynx, cracked red lips, cervical lymphadenopathy, non purulent conjunctivitis, along with desquamation of periungual region and swelling of hands and foot and  then suspect kawasaki disease.

## Laboratory Findings
There is an overlap of clinical findings between various types of sore throat and to narrow down the diagnosis, we use some laboratory tests and imaging studies.
- Rapid Antigen Detection Test(RADT)- It is first line diagnostic test for Group A Streptococcal (GAS) pharyngitis. A positive test is diagnostic of GAS infection and antibiotics should be started. If the test comes out to be negative, then a follow-up throat culture should be done.
- Throat culture-(90-99 % sensitive) - Though its best test, but takes time for the result. Used in non-emergency situations and when the RADT is negative. If positive, antibiotics are started, if negative, symptomatic management is given.
- Antistreptococcal antibodies are useful for the confirmation of previous GAS infection in case of acute rheumatic fever or other nonsuppurative complications.
- Monospot test- Used for the diagnosis of Infectious Mononucleosis due to Epstein-Barr virus.
- Peripheral blood smear shows atypical lymphocytes in Infectious Mononucleosis.
- Complete blood count (CBC), ESR and CRP are usually not used due to low predictive value

## Imaging Studies
Imaging studies are usually not used for uncomplicated sore throat and reserved for complicated cases only.
- X-Ray of neck, lateral view for suspected epiglottitis and airway compromise. Epiglottitis appears as thumb print sign in the x-ray.
- CT scan neck, there are no CT scan findings associated with sore throat. However, a CT scan may be helpful in the diagnosis of complications of sore throat, which include retropharyngeal abscess, peritonsillar abscess and suppurative cervical lymphadenitis.

# Treatment

## Medical Therapy
- Treatment for sore throat in most children is supportive care and systemic analgesia. Acetaminophen, NSAIDS Non Steroidal anti inflammatory drugs and steam inhalation help alleviate the pain.
- Corticosteroids are considered if pain is unresponsive to simple analgesics.
- They do not need antibiotics. Antibiotics are reserved for children in the high risk group ( immunosuppressed children, family or personal history of rheumatic heart disease or rheumatic fever) to prevent complications due to infection.
- The antibiotic of choice is Penicillin. Amoxicillin, Erythromycin or Azithromycin (for penicillin hypersensitivity) and first generation cephalosporins ( anaphylaxis to beta-lactams) are used as alternatives.

## Surgery
Surgical procedures are used in some specific conditions in children 
- Complete tonsillectomy is the mainstay of therapy for recurrent tonsillitis, if the episodes are
equal to or greater than 7 in a year.
equal to or greater than 5/year in 2 consecutive years.
equal to or greater than 3/year in 3 consecutive years.
- equal to or greater than 7 in a year.
- equal to or greater than 5/year in 2 consecutive years.
- equal to or greater than 3/year in 3 consecutive years.
- Partial tonsillectomy is the preferred procedure for tonsillar hyperplasia with ronchopathia.
- Aspiration or tonsillectomy punction is used for draining tonsillar abscess.

## Prevention
Certain measures for the primary prevention of sore throat are 
- Regular hand-washing.
- Keep the eating utensils of the infected person separately and wash them thoroughly.
- Toys of an infected toddler should be cleaned properly.
- Try to dispose of any dirty tissues and wipes , and wash your hands.
- A child with strep throat infection should not return to school until she or he finishes a 24 hour course of antibiotics with symptom improvement.

## Follow up
A follow-up is required if 
- fever and throat pain lasts for more than 48hours after starting treatment
- dysphagia
- new symptoms