Confluent and reticulated papillomatosis successfully treated with minocycline

Confluent and reticulated papillomatosis (Gougerot and Carteaud) is an uncommon disorder in which multiple pathogeneses have been speculated. Although oral minocycline treatment has been known to be effective in some cases, its pharmacological action(s) in the disease is not fully understood. We report a case of confluent and reticulated papillomatosis successfully treated with oral minocycline, Although no fungus was observed on potassium hydroxide (KOH) examination, a material which stained positive with periodic acid-Schiff stain was observed in the stratum corneum. After reviewing 9 previous reports, we noticed that in all 5 cases where there had been a good response to minocycline treatment, there were positive periodic acid-Schiff staining materials in the stratum corneum. In 4 cases, fungi were not demonstrated with KOH examination, The efficacy of minocycline treatment seems to depend on the existence of PAS positive materials in the stratum corneum. Further investigations are required to determine if confluent and reticulated papillomatosis is an infectious disorder.