Pharyngitis, tonsillitis, peritonsillar abscess and deep neck infection — formative SAQs

SAQ 1 (10 marks)

An 8-year-old boy presents with two days of sore throat, fever to 38.8 degrees Celsius, headache and abdominal pain. He has no cough or rhinorrhoea. On examination his tonsils are enlarged with white-yellow exudate, there are tender enlarged anterior cervical lymph nodes, and the rest of the examination is unremarkable. ^{[1] [2]}

1. Calculate his McIsaac score and explain how it guides your next step. (3) ^[2]
2. Outline your management plan including the antibiotic decision and doses if GAS is confirmed. (4) ^{[1] [3]}
3. Describe your safety-net advice and the circumstances under which the family should return urgently. (3) ^[1]

Model answer — SAQ 1

(1) McIsaac score and next step (3). The McIsaac score components are: fever above 38 degrees Celsius (present, 1 point), absence of cough (present, 1 point), tender anterior cervical lymphadenopathy (present, 1 point), tonsillar swelling or exudate (present, 1 point), and age three to fourteen years (present, 1 point). His total score is 5 out of 5, indicating a high pre-test probability of GAS. The correct next step is a throat swab or rapid antigen detection test — the IDSA mandates microbiological confirmation before treating in children, so I would test and treat if positive, rather than treat empirically on clinical grounds alone. ^{[2] [1]}

(2) Management plan (4). First, give analgesia: paracetamol 15 mg/kg orally every four to six hours (maximum 60 mg/kg/day) and encourage oral fluids. If the throat swab or RADT confirms GAS, first-line therapy is phenoxymethylpenicillin (penicillin V) for ten days — for a child of his weight (likely over 10 kg), 500 mg orally twice daily for ten days — or amoxicillin 50 mg/kg (maximum 1 g) orally once daily for ten days. If the test is negative, no antibiotic is needed; this is viral pharyngitis and analgesia with a safety-net suffices. I would not give amoxicillin empirically before the test result, because if he has EBV rather than GAS, amoxicillin would cause a characteristic maculopapular rash and a false penicillin-allergy label. ^{[1] [3]}

(3) Safety-net advice (3). Give a concrete, written safety-net: return at any time if his sore throat or fever worsens or does not improve after 48 hours of antibiotics (or after three to four days if untreated), if he develops difficulty swallowing, drooling, neck swelling or stiffness, a muffled voice, or if he simply looks more unwell. These symptoms may indicate a suppurative complication such as peritonsillar or deep neck abscess. Arrange a planned review at 48 to 72 hours if symptoms have not started to improve. Explain that he should complete the full ten-day course even after feeling better, to prevent acute rheumatic fever. ^[1]