Tonsillitis

Tonsillitis is a common presentation in both primary and secondary care. It is most frequently viral (rhinovirus, coronavirus, adenovirus, Epstein-Barr virus), but Group A beta-haemolytic Streptococcus (GABHS), specifically Streptococcus pyogenes, is a significant bacterial cause. The clinical challenge lies in identifying those likely to benefit from antibiotics while avoiding unnecessary prescriptions. The Centor Criteria and FeverPAIN score are validated tools for this purpose. Infectious Mononucleosis (Glandular Fever) caused by EBV must be considered in adolescents, as it presents with significant lymphadenopathy and hepatosplenomegaly; notably, giving amoxicillin in EBV infection can cause a characteristic maculopapular rash. Peritonsillar abscess (Quinsy) is a common complication requiring drainage. Chronic or recurrent tonsillitis can significantly impact quality of life, leading to school or work absence. The SIGN 117 criteria provide a standardized framework in the UK for determining which patients should be referred for tonsillectomy based on the frequency and severity of episodes over a 1-3 year period.

The palatine tonsils are part of Waldeyer’s Ring, a collection of lymphoid tissue in the pharynx that also includes the adenoids and lingual tonsils. They serve as a first-line immunological barrier against inhaled or ingested pathogens. Infection leads to follicular hyperplasia and inflammatory exudate within the tonsillar crypts. Bacterial tonsillitis, primarily by Streptococcus pyogenes, involves exotoxin production which can lead to systemic symptoms. Recurrent inflammation can lead to fibrosis and the formation of 'tonsilloliths' (tonsil stones)—calcified debris in the crypts. Peritonsillar abscess occurs when infection spreads through the tonsillar capsule into the surrounding loose connective tissue of the peritonsillar space, usually at the superior pole.

Patients present with a sore throat, fever, and painful swallowing. On examination, tonsils are erythematous and enlarged, often covered with a white/yellow follicular exudate. Tender anterior cervical lymphadenopathy is common. High-yield signs: Uvular deviation away from the affected side + Trismus (difficulty opening mouth) + 'Hot potato voice' = Peritonsillar Abscess (Quinsy). In Glandular Fever (EBV), look for shaggy white exudate, posterior cervical lymphadenopathy, and a palpable spleen. Complications include: Quinsy (requires incision and drainage), Otitis media, and the 'Stretococcal' triad (Scarlet fever). Long-term complications like Glomerulonephritis are mediated by immune-complex deposition (Type III hypersensitivity).

- Bedside: Clinical history and examination using Centor/FeverPAIN scores. Throat swab (not routinely recommended for ARTI unless recurrent or outbreak suspected).
- Bloods: FBC and Glandular Fever Screen (Monospot test or EBV serology) if symptoms persist >1 week or EBV suspected.
- Specialty: If Quinsy is suspected, needle aspiration is both diagnostic and therapeutic.

Medical: Paracetamol and Ibuprofen for pain. For bacterial suspicion (Centor ≥3 or FeverPAIN ≥4): Phenoxymethylpenicillin 500mg QDS for 10 days (MUST complete the course). If penicillin-allergic: Clarithromycin for 5 days. If Quinsy: Admission for IV fluids, IV antibiotics (e.g., Co-amoxiclav or Benzylpenicillin), and needle aspiration/incision & drainage. Surgical: Tonsillectomy for patients meeting SIGN criteria (7/1/y, 5/2/y, or 3/3/y). Complications of surgery include primary (<24h) and secondary (24h-2 weeks) haemorrhage; secondary haemorrhage is usually due to infection and requires admission/IV antibiotics.