Phenotypic characterization of congenital platelet defects (CPDs) may help physicians to determine disease subtypes, improving prognostic evaluations, according to research published in the American Journal of Hematology.
CPDs, rare disorders with clinically heterogenous presentations and outcomes, lack rigorous studies categorizing bleeding phenotypes. The International Society on Thrombosis and Haemostasis Bleeding Assessment Tool (ISTH-BAT), which documents a wide variety of bleeding symptoms, was designed as a screening tool, and does not offer phenotypic categorization of CPDs.
For this study, researchers “aimed to evaluate the bleeding phenotype of a large cohort of adult patients with CPDs and to search for correlations between the bleeding score and different laboratory phenotypes of CPDs.” All evaluated data were obtained from a nationwide cross-sectional study based in the Netherlands.
A total of 96 patients (64% women) were included in the study. The median ages for women and men were 38 years and 40 years, respectively. Patients were grouped by CPD subtype: isolated thrombocytopenia (23%), adenosine diphosphate (ADP) pathway defect (23%), thromboxane A2 (TxA2) pathway defect (16%), Glanzmann thrombasthenia (14%), dense granule deficiency (14%), complex abnormality (6%), and Bernard-Soulier syndrome (4%). By ISTH-BAT criteria, the median bleeding score was 9 for women and 6 for men.
Median bleeding scores were 21 for patients with Glanzmann thrombasthenia, 9 for Bernard-Soulier syndrome, 10 for dense granule deficiency, 7 for ADP pathway defect, 8 for TxA2 pathway defect, 6 for isolated thrombocytopenia, and 8 for complex abnormalities.
The most common forms of bleeding were heavy menstrual bleeding (81% of women), postpartum hemorrhage (74% of women), postoperative bleeding (64% overall), and post dental extraction (57% overall). Among women, 96% of bleeding cases were severe and heavy menstrual bleeding accounted for nearly 20% of the sum of all bleeding scores.
The least common forms of bleeding were central nervous system bleeding and urinary tract bleeding (2% and 4%, respectively).
“In conclusion, in CPD patients most frequently occuring symptoms are [heavy menstrual bleeding] and bleeding after a hemostatic challenge.
“Glanzmann thrombasthenia and female sex are associated with more severe bleeding phenotype,” the researchers concluded.
Blaauwgeers MW, Kruip MJHA, Beckers EAM, et al. Bleeding phenotype and diagnostic characterization of patients with congenital platelet defects [published online June 19, 2020]. Am J Hematol. doi: 10.1002/ajh.25910