Unexpected discovery of asymptomatic polycythemia vera in a patient with papulopustular rosacea caused by Demodex: A fortuitous association?

Abstract

Herein, we follow the case of a patient suffering from papulopustular rosacea caused by Demodex associated with polycythemia vera (PV), which was fortuitously diagnosed. Facial erythrosis must spark a suspicion of PV even if the case appears to be papulopustular rosacea caused by Demodex. This observation underlines the distinctive physiopathological processes of papulopustular rosacea caused by Demodex and that of PV; however, the dermatological clinical signs are similar. A skin biopsy does not allow us to differentiate the two pathological processes since only a blood sample analysis may exclude a diagnosis of PV. This case stresses the potential advantage of conducting systematic blood analyses for every patient presenting with clinical signs of rosacea, even of erythrodermic rosacea that does not respond to the classical therapeutics, to exclude the possibility of underlying asymptomatic PV. Dermatologists must be aware of the nonspecific dermal manifestations of this potentially fatal hematologic disorder