Muenke syndrome associated with multiple osteochondromas.

Muenke syndrome caused by the FGFR3 Pro250Arg mutation is associated with craniosynostosis, hearing loss, and various bony anomalies. Although this mutation is involved in bone growth and development, bony tumors are rare in this condition. We describe a patient with a molecular diagnosis of Muenke syndrome who also presented with multiple osteochondromas of the upper and lower extremities. This association has only been described once before in a patient with an isolated osteochondroma of the proximal tibia. Altered expression of FGFR3, an important mediator of chondrocyte proliferation and differentiation during in the growth plates of long bones, may help to explain the development of osteochondromatous lesions in this patient.