Use of ISTH bleeding assessment tool to predict inherited platelet dysfunction in resource constrained settings.

Background: The International Society of Thrombosis & Hemostasis (ISTH) bleeding assessment tool (ISTH-BAT) is used to record bleeding symptoms in patients with possible bleeding disorders.

Aim: To investigate the utility of the ISTH-BAT in predicting platelet dysfunction in individuals with suspected inherited platelet function disorders.

Method: Individuals with clinical evidence of bleeding and suspected inherited platelet function disorder and healthy volunteers were included in the study. The ISTH-BAT questionnaire was applied prior to light transmission aggregometry (LTA).

Results: A total of 261 participants were included (100 healthy volunteers, and 161 with suspected inherited platelet function disorders). The ISTH-BAT score in participants with suspected inherited platelet function disorders (median 2; interquartile range [IQR] 5-1) was significantly higher than in healthy volunteers (median 0; IQR 2-0). There was also a significant difference between participants with suspected inherited platelet function disorders with a platelet defect detected by LTA (median 4; IQR 8-3) and those with normal platelet function (median 2; IQR 3-1) (p < 0.001). The ISTH-BAT score was associated with a demonstrable platelet defect on platelet function testing (area under the receiver operating characteristic curve = 0.8 [95% confidence interval 0.72-0.87, p = < 0.001] and odds ratio 3.25 [95% confidence interval 2.13-4.37, p = < 0.001]).

Conclusion: The ISTH-BAT is a useful tool for documenting bleeding symptoms and the score obtained is also predictive of the presence of a platelet defect on LTA in patients with suspected inherited platelet dysfunction.