Topical steroids can mask tinea

THE LACK of scales may put you off diagnosing tinea, but ask what she has been applying to the rash.

Topical steroid creams will inhibit scale formation in tinea infections, suppress the body’s immune response to the fungal infection and indirectly encourage its growth. When the patient ceases the steroid, the rash worsens and there may be small pustules at the edge, as the immune system suddenly kicks in and mounts an inflammatory response.

Swabs of the pustules will be negative. Generally you can still raise a bit of scale