Pityriasis rotunda in childhood

Miscellaneous annular diseases

Annular lesions represent a unique macro-morphologic pattern in various skin disorders that may be found in pityriasis rotunda, elastosis perforans serpiginosa, subacute nodular migratory panniculitis, keratolysis exfoliativa, neutrophilic eccrine hidradenitis, hemophagocytic lymphohistiocytosis, and intentionally induced annular lesions. This group is highly heterogenous and variable in clinical presentation. Whereas some are benign self-limiting disorders like pityriasis rotunda, others such as hemophagocytic lymphohistiocytosis follow a chronic course or have a potential of being life-threatening. Epidemiology, pathogenesis, histopathology, clinical presentation and diagnosis, differential diagnosis, and treatment are discussed.

Caso para diagnóstico

A pitiríase rotunda é dermatose rara, caracterizada por placas circulares bem definidas, hipo ou hiperpigmentadas, localizadas no tronco e porção proximal dos membros. São descritos dois subtipos: o tipo I acomete pacientes negros e orientais sem história familiar de pitiríase rotunda e está relacionado com doença sistêmica concomitante; o tipo II ocorre em caucasianos com história familiar e sem doença subjacente. Descreve-se um caso do tipo I em mulher negra de 39 anos.