Otitis externa — branching viva

Opening — the swimmer with a painful discharging ear

Examiner: An eight-year-old girl who swims daily presents with two days of right ear pain, a mucky discharge and itching, crying when the ear is touched. Talk me through your immediate thoughts and your examination. [1]

Candidate should cover: the diagnosis of acute diffuse otitis externa (swimmer's ear) from the water-exposure history, otalgia, otorrhoea and pruritus; the two localising signs — tenderness on pressing the tragus and pain on pulling the pinna backwards — that place the disease in the canal rather than the middle ear; and a cleared view of a normal tympanic membrane excluding acute otitis media. [3]

Branch 1 — analgesia-led, topical-first management

Examiner: How will you manage her, and why are you not prescribing oral antibiotics? [5]

Candidate should cover: analgesia with paracetamol and ibuprofen, because the AAO-HNS guideline makes adequate pain control a key action statement; aural toilet to clear debris; a topical antimicrobial with corticosteroid instilled for about seven days, keeping the ear dry and avoiding cotton buds; and the 2023 systematic review finding topical antimicrobials effective with no added benefit from oral antibiotics in uncomplicated disease, reserving oral therapy for spreading cellulitis or systemic features. [1] [5]

Branch 2 — the too-swollen canal and the perforation question

Examiner: The canal is now so swollen that drops will not pass. What do you do? And if you were unsure whether the eardrum was intact, how would your choice of drop change? [1]

Candidate should cover: inserting an ear wick for two to three days to deliver the drops beyond the stenosis, then completing the course with direct drops; and switching from an aminoglycoside (neomycin, polymyxin B) to a fluoroquinolone (ciprofloxacin) drop when the tympanic membrane may be perforated, because of the aminoglycoside ototoxicity concern. [3]

Branch 3 — the immunocompromised child with a facial palsy

Examiner: Now a different child: a six-year-old on chemotherapy, neutropenic, with severe unremitting ear pain, granulation at the bony-cartilaginous junction, and a facial palsy. What has changed, and what will you do? [7]

Candidate should cover: the recognition of necrotising (malignant) otitis externa with skull-base osteomyelitis from the severe unremitting otalgia, the granulation at the bony-cartilaginous junction and the facial palsy in an immunocompromised host; admission with an ear swab and granulation biopsy, C-reactive protein and erythrocyte sedimentation rate, blood glucose and HbA1c, and skull-base imaging (CT temporal bone first-line, MRI for cranial-nerve and soft-tissue detail, technetium to diagnose and serial gallium to monitor); and prolonged systemic antipseudomonal therapy with oral ciprofloxacin 10 to 20 mg per kilogram (maximum 750 mg) every 12 hours for many weeks, or intravenous ceftazidime or cefepime, stopping when CRP and ESR normalise. [9] [10]