LEOPARD syndrome without hearing loss or pulmonary stenosis: a report of 2 cases

LEOPARD syndrome is an autosomal dominant disease caused by germline mutations in the RAS-MAPK (mitogen-activated protein kinase) pathway. LEOPARD is an acronym for the main manifestations of the syndrome, namely, multiple Lentigines, Electrocardiographic conduction abnormalities, Ocular hypertelorism, Pulmonary stenosis, Abnormalities of genitalia, Retardation of growth, and sensorineural Deafness. None of these characteristic features, however, are pathognomonic of LEOPARD syndrome, and since they are highly variable, they are often not present at the time of diagnosis. We describe 2 cases of LEOPARD syndrome without hearing loss or pulmonary stenosis in which diagnosis was confirmed by identification of a mutation in the PTPN11 gene. Regular monitoring is important for the early detection of complications, as these can occur at any time during the course of disease.