The diagnosis of psoriasis can be made by clinical observation without laboratory tests in most cases. The disease however can be confused with many other entities. Nummular eczema, tinea corporis, cutaneous T-cell lymphoma, atopic dermatitis, contact dermatitis and yeast infections in skin folds can all be confused with psoriasis.

nummular eczema

Nummular eczema is a chronic disease that looks like psoriasis


This case of ringworm was initially misdiagnosed as psoriasis

cutaneous t-cell lymphoma

A patient with ctcl. A biopsy was required to differentiate this from psoriasis


Yeast infections (candida) occur in skin folds. Psoriasis in skin folds can have the exact same appearance. Psoriasis in skin folds is called inverse psoriasis.