Gianotti-Crosti syndrome

Gianotti-Crosti syndrome (GCS) is a relatively common dermatosis, seen worldwide, primarily affecting children between 2 and 6 years of age. The classic physical finding is an asymptomatic self-limited papulovesicular exanthem; on rare occasions there are associated systemic signs and symptoms. GCS is usually associated with viral infections or immunization, but the pathogenesis remains a mystery. Since the initial description by Gianotti1 in 1955, the classification of GCS has varied over the decades, primarily reflecting increased sophistication in virology. Many complex terms, explained below, have led to diagnostic confusion and conflicting views in different parts of the world. The diagnosis of GCS is not as straightforward as textbooks sometimes suggest, as the clinical spectrum is quite varied.