Scalp Nodules as Presenting Sign of Fibrodysplasia Ossificans Progressiva

Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disorder characterized by progressive and irreversible soft-tissue and joint ossification. FOP is caused by mutations in the ACVR1 gene; no effective treatment is known. Early clinical diagnosis is important to avoid unnecessary diagnostic and therapeutic procedures and soft-tissue injuries, all of which can exacerbate the disease. This study shows that neonatal scalp nodules plus great toe malformations is a common presentation of FOP. Molecular testing, rather than lesional biopsy, should be performed to confirm the diagnosis, as biopsy can exacerbate FOP locally and at distant sites. We hope that recent molecular advances in the genetics of FOP will identify effective treatments for this devastating disease.