Fibrodysplasia ossificans progressiva in a cat

A young, female Maine coon cat was referred for investigation of anorexia, anaemia and limited mobility. On CT of the limbs, thorax and abdomen, there was evidence of multiple, mineralised lesions within the muscles of all four limbs. Following a histopathological examination of the incisional biopsies obtained from the lesions, a diagnosis of fibrodysplasia ossificans progressiva (FOP) was made. FOP is a rare genetic condition in people, which results in a shorter life span due to progressive ossification of connective tissue. To the authors’ knowledge, this is the first report of FOP observed in a cat in the UK. In this case, an improvement in mobility was observed following diagnosis and supportive management.