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Cat bite in pregnancy with immediate penicillin hypersensitivity — MSRA MCQ

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HardInfectious DiseasesCat bite in pregnancy with immediate penicillin hypersensitivityMSRA

A 28-year-old woman who is 22 weeks pregnant presents 45 minutes after being bitten by her domestic cat. The cat is well, has not travelled outside the UK and is vaccinated. The bite is a puncture wound to the dorsum of her right index finger; it has broken the skin and drawn blood. There is no tendon exposure, impaired movement, sensory deficit, spreading erythema, discharge, fever or lymphangitis. She is systemically well and can take oral medication. The wound has been irrigated. Her tetanus immunisation is up to date. At age 19, she developed wheeze, hypotension and generalised urticaria within 20 minutes of taking amoxicillin. Which is the most appropriate antimicrobial management today?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: D — Seek urgent specialist advice to select an appropriate oral antibiotic prophylaxis regimen

Explanation lettering: E = shown as C · C = shown as E

This is an uninfected cat bite that has broken the skin and drawn blood, so antibiotic prophylaxis is indicated rather than observation alone. She is well, has no deep-structure injury and can take oral treatment, so intravenous therapy and hospital referral are not indicated. Co-amoxiclav is the usual first-choice oral agent and is an appropriate indication in pregnancy, but her previous immediate reaction with hypotension, wheeze and urticaria is a convincing history of IgE-mediated penicillin hypersensitivity. It should therefore not be prescribed. Doxycycline with metronidazole is the standard oral alternative when co-amoxiclav is unsuitable in non-pregnant adults, but doxycycline is contraindicated in pregnancy. NICE specifically advises seeking specialist advice for an alternative oral regimen when a pregnant person cannot receive co-amoxiclav. This should be arranged urgently so that suitable prophylaxis can be started without unnecessary delay. A is incorrect because the bleeding cat bite requires prophylaxis. B ignores a serious immediate penicillin allergy. C applies the usual non-pregnant alternative despite pregnancy. E over-escalates route and setting in a clinically well patient, and cefuroxime also requires caution in immediate penicillin hypersensitivity.

Reference: NICE NG184: Human and animal bites: antimicrobial prescribing — Recommendations (4 November 2020) — https://www.nice.org.uk/guidance/ng184/chapter/Recommendations Doxycycline 100 mg Capsules — Summary of Product Characteristics (2026) — https://www.medicines.org.uk/emc/product/13082/smpc