[Treatment of osteogenesis imperfecta with (+)-catechin (author's transl)]

4 girls aged 4--12 years with various forms of osteogenesis imperfecta were treated with (+)-catechin for several months. Bone punch biopsies from the iliac crest were investigated by electron microscopy before and during treatment. The frequency of fractures decreased clinically. There were no radiographic changes in the bones and there were no side effects. Electron microsopy showed a dilated coarse endoplasmatic reticulum with infrequent ribosomes, thin collagen fibrils and decreased predominantly disseminated mineralisation before treatment. Under the influence of treatment electron microscopical aspects of the bone improved. The cisternae of the endoplasmatic reticulum were arranged parallel with densely packed ribosomes, collagen fibrils were wider and in closely packed bundles and mineralisation was clearly improved. The electron microscopic findings are evidence for a possibly beneficial influence of (+)-catechin in some cases of osteogenesis imperfecta.