RESUMO
The enchondromatosis include a heterogeneous group of congenital disorders characterized by the presence of multiple enchondromas associated with musculoskeletal malformations and the main complication is the risk of malignant transformation to chondrosarcoma. The hereditary multiple exostosis is an entity with autonomus dominant inheritance pattern, characterized by having multiple exostosis capped benign cartilage and heterogeneous clinical manifestations. Mutations of EXT1 and EXT2 genes have been cloned and are responsible for over 80% of the cases. We report a case of a six years old female with a diagnosis of hereditary multiple exostosis, that has been multidisciplinary assessed at our institution being the second case study in the Medical Genetics Unit of the Universidad de Los Andes; the clinical and genetic aspects, the differential diagnosis with Oilier disease and Maffucci syndrome were reviewed.