Isaac is a three-year-old boy brought in by his parents with a three-day history of progressive, painless, non-pruritic pustules on his right palm.

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<p>Isaac is a three-year-old boy brought in by his parents with a three-day history of progressive, painless, non-pruritic pustules on his right palm. He is otherwise well, with no fever, systemic symptoms or past history of note.</p><p>The family, including Isaac’s five-year-old sister and new pet rabbit, are all well and have no similar symptoms. There is no family history of atopy or other dermatological conditions. On examination, vital signs are within normal limits.</p><p>There is non-tender erythema and vesicles and pustules are localised on the ulnar aspect of the right palm. The rest of the dermatological and systems examination is normal. A swab of pustule fluid is sent for bacterial and viral culture and is negative.</p>

Dr Kate Kelso is a GP and medical editor at Australian Doctor.