Oral ulcers and mucosal disease — structured clinical encounter

Candidate brief

You are the paediatric registrar in the emergency department. A two-year-old boy has three days of high fever, drooling and refusal of all fluids. On examination his gingiva is diffusely swollen, red and bleeding, with shallow vesicles and ulcers across the gingiva, tongue and lips and tender cervical lymphadenopathy. [1]

Task

Take the focused history, present your differential, justify your hydration-first assessment and your early oral aciclovir, and explain when you would use intravenous rather than oral therapy. Be prepared to defend the distinction between herpetic gingivitis and enteroviral or aphthous disease. A second child — a ten-year-old with recurrent scarring major aphthae — will then be introduced for contrast. [2]

Discussion anchors

• Diagnosis and hydration: primary herpetic gingivostomatitis from the fever, drooling and diffuse anterior gingival vesicles and ulcers, with dehydration from refusal to drink as the practical threat; assess moist mucous membranes, capillary refill and urine output and correct any deficit with nasogastric or intravenous fluid where oral hydration cannot be maintained. [1]
• Antiviral therapy: oral aciclovir 15 mg per kilogram per dose (maximum 200 mg per dose) five times daily for five to seven days started within 72 hours of onset, supported by the 1997 randomised trial and a 2023 systematic review; use intravenous aciclovir for severe disease, immunocompromise or a child who cannot maintain hydration. [1] [2]
• Differential: diffuse anterior gingivitis distinguishes herpes simplex from the posterior palate ulcers with a rash of enteroviral disease and the few round non-keratinised aphthae of recurrent aphthous stomatitis. [9]
• Contrast case: the ten-year-old with recurrent ulcers over ten millimetres lasting weeks and scarring has major aphthous stomatitis; send a full blood count with differential, iron studies, serum folate and vitamin B12, coeliac serology with total IgA and C-reactive protein, manage with a topical corticosteroid, chlorhexidine and a topical analgesic, and consider Behcet disease, inflammatory bowel disease and cyclic neutropenia if systemic signs appear. [9] [10]
• Disposition and safety-net: discharge the well-hydrated child on analgesia and early aciclovir with a clear safety-net for dehydration, spreading lesions and refusal to drink; refer any single ulcer persisting beyond two to three weeks despite removing trauma. [9]