INTRODUCTION

Pharyngitis is inflammation of mucosa and underlying tissue of pharynx.

It is clinically divided into two category-nasopharyngitis and pharyngotonsillitis.

Nasopharyngitis is associated with nasal sumptomps like running nose or itching in the nose due to inflammation of nasal mucosa and it is usually of viral origin.

Pharyngotonsillitis is associated with inflammation and enlargement of palatine tonsils.

Sore throat is one of the common symptoms requiring frequent OPD visit  by children which constitutes about 30% of all upper respiratory tract infections in children.

The most important is Group A Beta haemolytic Streptococcal(GABHS) Pharyngitis as  there is 3% chance of it being complicated by acute rheumatic fever with its cardiac complications.

Approximately 25% of all sore throat are caused by bacteria.

GABHS pharyngitis commonly affects children between the age group of 2 to 15 years,Most affected children are of school age.

It commonly spreads by close contacts in the family or in schools

Approximately  50% of  the close contacts  of the index case in the family or in the school get infected by the bacteria through respiratory route.

GABHS Pharyngitis usually occurs in rainy,winter or spring seasons.

ETIOLOGY

Most commonoly ,it is caused by viruses

Common viruses causing acute pharyngitis are adenovirus,enterovirus,influenza virus,parainfluenza virus,coxsackie virus ,Ebstein- barr virus,rhinovirus,metapneumovirus,and herpes simplex virus.Primary infection with HIV may present as pharyngitis.

Less commonly it is caused by bacteria

Most important are GABHS and Corynebacteriun diphtheria

Other bacteria causing pharyngitis are Arcanobacterium hemolyticum,Fusobacteriun necrophorum,Neisseria gonorrhoeae and Mycoplasma pneumonia

PATHOGENESIS

Two major virulence factors of GABHS are M protein and erythrogenic exotoxins

M protein resists phagocytosis by polymorphonuclear neutrophils and causes pharyngitis which confers type specific immunity.

Erythrogenic toxins are of 3 types,A,B and C.The most virulent is type A responsible for causing scarlet fever with fine papular rashes.

These exotoxins confers type specific immunity,so scarlet fever can occur for 3 times in life

CLINICAL FEATURES

The most important and the most challenging is to differentiate sore throat due to GABHS from other causes,because of its potential to cause acute Rheumatic fever and its cardiac complications.

There is no single clinical symptom or clinical sign ,which can make a definite diagnosis of GABHS Pharyngitis.

The incubation period is 2-5 days

SYMPTOMS

Usual presentation of GABHS Pharyngitis is sudden onset of sore throat,pain in throat at rest or even after swallowing saliva,fever, in the absence of cough.

Common associated symptoms are headache,pain abdomen and vomiting.Limb pain due to myalgia is also common complaint.

SIGNS

The pharynx is red and erythematous-redness may be a part of generalized redness of viral origin but the differentiating point is that in case of GABHS infection the pharynx is more red as compared to other area of oral redness.

The tonsils are enlarged and in classical case, it is covered with yellow blood tinged exudate.

Exudate may also be seen on posterior pharynx with petechiae or doughnut lesions ,which may also be found over soft palate.

There may be redness and swelling of uvula with stippling

There may be enlargement and tenderness of anterior cervical lymph nodes.

Some additional signs favouring scarlet fever may be present in the form of fine ,red, papular raches over body including face and neck which feels like sand paper and looks line sunburn with goose pimples,perioral pallor and strawberry tongue.

MODIFIED CENTOR SCORING FOR DIAGNOSING GABHS PHARYNGITIS

Components are

1. age 3-14 years
2. temperature more than 38 degree celcius
3. absence of cough
4. enlarged and tender anterior cervical lymph nodes
5. swelling or exudates over tonsils

Each component is given one point

Score 4 or more is highly suggestive of GABHS Pharyngitis,score o-1 should not be tested for or given treatment for GABHS Pharyngitis

Another important bacterial cause of acute pharyngitis,which should be looked for and treated in children is Diphtheria.

It is caused by Corynebacterium diphtheria,clinically characterized by grey to black adherent membrane over throat with  extension beyond the faucial area ,especially over soft palate and uvula with symptom of dysphagia and relatively ,lack of fever.,

shallow ulceration of upper lips and external nares and neck swelling may be found.

CLINICAL FEATURES OF VIRAL PHARYNGITIS

Its onset is gradual as compared to bacterial which is sudden in onset.

It is usually associated with cough,coryza,running nose,conjuntivitis and hoarseness of voice.

SPECIFIC FEATURES OF SOME VIRAL PHARYNGITIS

Adenovirus-pharyngitis is associated with conjunctivitis and diarrhoea.

Coxsackievirus- herpangina with small greyish vesicles and punched out ulcers which is extremely painful.There may be yellowish white nodules in the posterior pharynx called acute lymphonodular pharyngitis

Ebstein barr virus- causative agent of infectious mononucleosis

generalized fatigue,rashes over body and face,prominent tonsillar enlargement with exudate.

cervical lymphadenopathy is posterior as compared to anterior in GABHS Pharyngitis.

hepatosplenomegaly.

HERPES SIMPLEX VIRUS –

Pharyngitis with high fever and gingivostomatitis

LABORATORY DIAGNOSIS

The gold standard is throat swab smear examination and culture

Technique of swab collection should be perfect for appropriate result-it should be obtained by vigorous swabbing of both tonsillar surfaces or fossae and posterior pharynx.Swabbing of soft palate and uvula should be avoided as it dilutes the innoculums

It has 90-95% sensitivity

Albert staining should be done, if Diphtheria is suspected, and if drumstick appearance is visible, culture should be done to confirm Corynebacterium Diphtheriae ,because diphtheroids are the commensals in throat ,having similar look on smear examination.

RAPID ANTIGEN DETECTION TEST(RADT) FOR GABHS

It is done on throat swab and detects nitrous acid extraction of carbohydrate antigen of GABHS.

Is has specificity of more than 95% but low sensitivity ,so negative test should be confirmed by culture but positive test need not confirmation by culture.

This test is available at selected centres in India

In case of suspected EBV Pharyngitis IgM Antibody against viral capsular antigen can be dectected in addition to many atypical lymphocytes in CBC

TREATMENT

Viral as well as GABHS Phryngitis is self limiting ,but antibiotic therapy is needed to prevent the complication of Acute Rheumatic fever and its cardiac complications

It works when given within 9 days of onset of symptoms

Child becomes non-infectious after 24 hours of instituting antibiotic therapy

INDICATIONS OF STARTING ANTIBIOTIC WITHOUT AWAITING CULTURE RESULT

• Symptomatic pharyngitis with positive RADT
• Pharyngitis with past history of acute rheumatic fever in child or recent history of acute rheumatic fever in family
• Pharyngitis with a household contact with documented Streptococcal pharyngitis
• pharyngitis with clinical features suggestive of scarlet fever

ANTIBIOTIC

The preferred drug is oral amoxicillin because it tastes good,easily available,dispersible tablet is available for children and can be given once daily

The dose is 50 mg /kg,minimum of 750 and maximum of 1 gm once daily for 10 days

A single dose of benzathine penicillin ensures compliance and provides adequate blood levels for 10 days.

Dose is 6 lakhs unit i.m. for child <27 kg and 12 lakhs unit i.m. for child more than 27 kg

TREATMENT OPTIONS FOR CHILD ALLERGIC TO PENICILLIN

Azithromycin,12mg/kg ,maximum 500mg,once daily for 5 days

Clarithromycin,15 mg/kg/day bid,a maximum of 250mg bid /day for 10 days

clindamycin 20 mg /kg/day tid,a maximum of 1.8 gm/day for 10 days

In cases of multiple episodes over a period of months or years ,Amoxiclav or clindamycin shoud be given as these yield high rates of eradication of GABHS in these cicumstances.

First to third generations cephalosporins can be given but if given ,it should be given for 10 days.

SYMPTOMATIC TREATMENT

It is an important part of management.

oral paracetamol or ibuprofen should be given for fever and pain in throat.

Warm saline gargle gives relief in throat

Lonzenges containing phenol,menthol or benzocaine provides local relief.

TREATMENT OF DIPHTHERIA

Stabilization of the child with care of airway

Diphtheria antitoxin 50000units to 120000 units i.vi depending on the extent of lesions

Aqueous crystalline penicillinG 40000 units /kg /dose ,i.v. 6hourly or erythromycin 15 mg/kg/dose,maximum 2gm/day oral or i.v. for 14 days.

For contact prophylaxis, same dose of erythromycin for 7 days or single intramuscular injection of Benzathine penicillin ,6 lacs units for <30 kg and 12 lacs unit for 30 kg or more is recommended

COMPLICATION

Parapharyngeal,retropharyngeal and peritonsillar abscess

pronlonged pharyngitis of more than 1-2 weeks durations suggest neutropenia or recurrent fever syndrome

LEMIERRE SYNDROME 

It is a serious complication of pharyngitis caused by Fusobacterium necrophorum

It is characterized by septic thrombophlebitis of internal jugular vein with pulmonary embolism causing pulmonary infiltrates and hypoxia

Non suppurative complications are acute rheumatic fever and acute glomerulonephritis

INDICATION OF TONSILLECTOMY– Severe ,recurrent ,culture proven pharyngitis due to GABHS with >7 episodes in previous year or >5 episodes each year in preceding 2 years.

It lowers the incidence of pharyngitis for 1-2 years

Most children have fewer epsodes over the years spontaneously ,so risk benefit should be balanced

 

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