Sally, 41, presents with a pruritic erythematous submammary and axillary rash.

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Sally, 41, presents with a pruritic erythematous submammary (pictured) and axillary rash. This has been present for the past two months.

Sally has tried an over-the-counter topical antifungal, but this has not helped. She denies using any new medicines or skin care products.

Sally is generally well, with Crohn’s disease that is well controlled with infliximab. There is no family history of note.

Examination is unremarkable apart from the rash pictured with similar bilateral axillary lesions, which do not fluoresce on Wood’s lamp examination. Fungal microscopy and bacterial culture are negative.