[Diagnosis of inherited diseases of platelet function. Interdisciplinary S2K guideline of the Permanent Paediatric Committee of the Society of Thrombosis and Haemostasis Research (GTH e. V.)].

Congenital disorders of platelet function are a heterogeneous group of disorders that are often not detected until bleeding occurs. In clinical settings only a few methods have proven to be useful for identification and classification of inherited platelet disorders. For a rational diagnostic approach, a stepwise algorithm is recommended. Patient history and clinical investigation are mandatory. Von Willebrand disease and other coagulation disorders should always be ruled out prior to specific platelet testing. Platelet count, size, volume (MPV) and morphology may guide further investigations. The PFA-100® CT is suited for screening for severe platelet defects. Platelet aggregometry allows assessment of multiple aspects of platelet function. Flow cytometry enables diagnosis of thrombasthenia Glanzmann, Bernard-Soulier syndrome and storage pool defects. Molecular genetics may confirm a putative diagnosis or pave the way for identifying new defects. We present an unabridged version of the interdisciplinary guideline.