Four severe haemophilia A patients exhibited inhibitor. Three patients had low inhibitor of 1.3, 4.4 and 4.4 BU, whereas one patient had high inhibitor of 50 BU. Only one severe haemophilia B patient had inhibitor of 4.6 BU. All patients abstained from blood component or factor concentrate administration for at least 5 days before participating in the study. The normal controls had no personal or family history of bleeding disorders and did PF-2341066 not take any medication. Coagulation tests included levels

of factor VIII clotting activity (FVIII:C), factor IX clotting activity (FIX:C) and inhibitor to FVIII:C and FIX:C was determined by standard methods [2, 3] in every subject. The median levels of FVIII:C and FIX:C among the normal controls were 110% (interquartile range 99–130%) and 96% (interquartile range 90–115%), respectively. The results of the VCT of whole blood alone and the correction of VCT after adding factor VIII and factor IX concentrates among haemophilia and

normal controls are shown in Table 2 (excluding one haemophilia A patient with high inhibitor). ZD1839 in vitro The VCT of whole blood alone was significantly prolonged in haemophilia A patients with severe and moderate degrees compared with those of mild degree (P = 0.037). On the contrary, some haemophilia B patients with severe and moderate degrees had a slightly prolonged VCT, whereas some of them had a significantly prolonged VCT similar to those of haemophilia A patients. However, both haemophilia A and B patients with mild degree had minimally elevated VCT which was slightly more prolonged than those of normal controls. Subsequently, 34 haemophilia patients’ VCTs were corrected to the normal range of less than 15 min after adding factor VIII or factor IX concentrate accordingly, no matter whether the check details VCT of whole blood alone was prolonged or minimally elevated. One severe haemophilia A patient with high inhibitor of 50 BU. He had markedly

prolonged VCT which could not be normalized after adding factor VIII concentrate. The status of haemophilia A and B could be accurately diagnosed for the remaining 34 patients. Patients with haemophilia A had a prolonged or minimally elevated VCT which normalized after adding factor VIII concentrate in the second tube. Vice versa, patients with haemophilia B had a prolonged or minimally elevated VCT which normalized after adding factor IX concentrate in the third tube. The correction of VCT expressed as time and percentage of correction after adding factor VIII concentrate in patients with haemophilia A was significantly shortened and higher than those after adding factor IX concentrate with P values of 0.0001. Similarly, patients with haemophilia B also had significantly shortened VCT and higher percentage of correction after adding factor IX concentrate compared with those after adding factor VIII concentrate with P values of 0.012.