Hyperpigmented tinea versicolor.

Examination of specimens from lesions of hyperpigmented tinea versicolor and from unaffected skin disclosed that the lesions showed increased stratum corneum turnover (8.2 +/- 0.6 vs 14.8 +/- 0.4 days, respectively), slight to moderate routine histological changes, such as acanthosis and perivascular inflammation, and dramatic electron microscopical changes (larger, singly distributed melanosomes vs small, packaged melanosomes, respectively). Brown hyperpigmentation in tinea versicolor appears to arise from an increase in melanosome size and a change in their epidermal distribution pattern.