An arthropathic form of osteogenesis imperfecta.

A 14-year-old girl gradually developed severe osteoporosis and destructive generalized joint disease, resulting in joint stiffness and anchyloses. She also had moderate hydroxyprolinemia and hydroxyprolinuria. Rheumatoid arthritis was highly unlikely. Anamnestic data revealed two long bone fractures. Collagen biosynthesis was studied in fibroblasts cultured from the patient's skin. Chromatograms of 3H-labelled culture media proteins on ion exchange celluloses revealed an increased ratio of type III collagen to type I collagen when compared with the chromatograms of age-matched control fibroblasts. This finding is typical of certain cell strains in osteogenesis imperfecta. The patient might thus express a new variety of osteogenesis imperfecta with chronic arthropathy.