Based on these results it is recommended that all haemophilia centres have available a chromogenic or two-stage clotting assay and that this should be performed in subjects with normal APTT and one-stage FVIII activity in the presence of a personal or family history consistent with mild haemophilia A. Platelet

function testing is important for the diagnosis of many inherited and acquired bleeding disorders but it has lacked standardization [12]. Furthermore, heterogeneity in the biology and laboratory manifestations of platelet function disorders poses additional challenges check details to standardizing the diagnostic testing [12–15]. Recent surveys, including the largest worldwide survey of clinical laboratories by the International Society on Thrombosis and Haemostasis [16], have been helpful to identify which aspects of commonly performed platelet function tests, such as light transmission aggregation (LTA), show the greatest deviation in practice [17–19]. The lack of standardization in testing has led a number of organizations to

develop guidelines and recommendations, using expert opinion and/or systematic reviews of the literature [12,20–23]. Presently, many diagnostic laboratories need to update their practices in order to meet these new recommendations [22]. A number of organizations have led efforts to improve and standardize the laboratory assessment of platelet disorders [11,17–19,22,24]. http://www.selleckchem.com/products/lee011.html Some efforts have focused on defining common practices [16–19,24] and the heterogeneity in practice stimulated the development of published guidelines from organizations such as the International Society on Haemostasis and Thrombosis and the Clinical and Laboratory Standards Institute [22]. Presently, the most common type of diagnostic assay

used to investigate a known or suspected platelet function disorder is an assessment Amino acid of platelet aggregation function, often by LTA [12,16,17]. Although some laboratories perform ‘screening tests’ [such as the bleeding time and Platelet Function Analyzer-100® (Siemens/Dade-behing, Marburg, Germany) closure time] [19], neither the bleeding time nor the closure time has sufficient sensitivity to rule out common platelet function disorders [23,25]. LTA has considerable diagnostic utility when performed by rigorously standardized procedures [25,26] with validated reference intervals [27] on samples from individuals referred for bleeding problems. Laboratories need to consider the potential for false positives, as LTA abnormalities with two or more agonists are much more highly predictive of a bleeding disorder than a single agonist abnormality [25].