Aktualne zasady diagnostyki oraz zmiany w klasyfikacji wrodzonej łamliwości kości (Osteogenesis imperfecta)

The definition and classification of Osteogenesis imperfecta (OI) have been transformed over the last two decades. In the past, it has been described as a type I collagenopathy due to identified mutations in COL1A1 and COL1A2 genes encoding collagen type I which led to all OI cases. At least 10 genes involved in the process of type I collagen biosynthesis have been described until now. COL1A1/2 genes are responsible for almost 90% of OI prevalence. However, there is a number of newly discovered genes which encode proteins involved in posttranslational modification of procollagen, whereas mutations in these genes lead to approximately 10% types of OI inherited recessively. In this review, we provide an update on the traditional Sillence classification of the disease and we also report recent developments in understanding of underlying mechanisms responsible for OI. The paper discusses currently published modification of the OI classification (new types of the disease: V-XV) and a new approach to the diagnostic methods focusing mainly on phenotypic manifestation, independent of the genetic or molecular background. We point out the importance of clinical symptoms and severity of the disorder of which both appear the most useful criteria for management of OI patients in everyday practice.