Streptococcal Tonsillitis

Streptococcal tonsillitis is acute infection of the palatine tonsils by Streptococcus pyogenes (group A), and sometimes by group C or G streptococci, presenting with tonsillar swelling and exudate. It affects school aged children and young adults and may recur.

• Spread by respiratory droplets, with an incubation period of 2 to 5 days.
• Treatment prevents rheumatic fever and reduces suppurative complications.

Fever, severe sore throat, odynophagia, otalgia, tender jugulodigastric nodes, enlarged erythematous tonsils with pus on the surface, halitosis, headache; children may have abdominal pain and vomiting.

• Differential diagnosis: viral tonsillitis, infectious mononucleosis (large exudative tonsils, posterior nodes, splenomegaly), diphtheria, acute leukaemia, agranulocytosis, Vincent angina, tonsillar lymphoma, acute HIV infection, Fusobacterium infection (Lemierre syndrome), peritonsillar abscess.
• Complications: peritonsillar abscess (quinsy), parapharyngeal abscess, cervical lymphadenitis, otitis media, sinusitis, acute rheumatic fever, post streptococcal glomerulonephritis, scarlet fever, toxic shock syndrome, recurrent tonsillitis.

Clinical features with confirmatory test.

• Rapid antigen detection test; throat swab culture; full blood count and monospot test if prolonged or atypical.
• Blood tests and imaging only for complications: ultrasound or CT neck for abscess.
• Urinalysis and ECG if rheumatic fever or glomerulonephritis is suspected.

Treat with penicillin to eradicate the organism and prevent complications.

• Supportive: rest, oral fluids, soft cool diet, warm saline gargles, analgesia, exclusion from school until 24 hours after antibiotics, hygiene and no sharing of utensils.
• Pharmacological: phenoxymethylpenicillin 500 mg twice daily (or 250 mg four times daily) for 10 days (children 250 mg two to three times daily); or benzathine benzylpenicillin 1.2 million units IM single dose (600,000 units for children under 27 kg); or amoxicillin 500 mg three times daily for 10 days (children 50 mg/kg/day). Severe tonsillitis with dehydration: benzylpenicillin 1.2 g IV every 6 hours (children 50,000 units/kg every 6 hours) until able to swallow. Penicillin allergy: azithromycin 500 mg once on day 1 then 250 mg daily for 4 days, or clindamycin 300 mg three times daily for 10 days, or cefalexin 500 mg twice daily for 10 days. Paracetamol 1 g every 6 hours (15 mg/kg) and ibuprofen 400 mg every 8 hours (10 mg/kg); dexamethasone 10 mg orally single dose for severe pain in adults. Avoid amoxicillin if infectious mononucleosis is possible.
• Procedures: incision and drainage or needle aspiration of peritonsillar abscess; tonsillectomy for recurrent tonsillitis (7 or more well documented episodes in 1 year, 5 or more per year for 2 years, or 3 or more per year for 3 years), or for airway obstruction and recurrent abscess.
• Special groups: pregnancy, penicillin; rheumatic heart disease, prophylaxis with benzathine benzylpenicillin 1.2 million units IM every 3 to 4 weeks; HIV, treat similarly and test for coinfection; elderly and diabetic, low threshold for admission.
• Red flags: trismus, drooling, uvular deviation, muffled voice, stridor, neck swelling, dehydration, high fever beyond 48 hours of treatment, tender neck swelling after sore throat (Lemierre syndrome).
• Follow-up: review at 48 to 72 hours; watch for rheumatic fever and nephritis features for 4 weeks; ENT referral for recurrent episodes.