First Report from the Saudi Bleeding Screening Study: Are Platelet Disorders More Common in Arabs?

Inherited platelet disorders (IPDs) are a heterogeneous group of diseases affecting platelet production and function with variable clinical severity. The prevalence is estimated to be less than 1:1000,000 worldwide in most common types. There are no population based epidemiological studies in Arab ethnicity to estimate the prevalence of IPD.

Over 2 years we had conducted questioner-based survey among high school and 1^st year university students in Riyadh city, Saudi Arabia. We had interviewed 3881 students (1901 (49%) male and 1980 (51%) female). Out of these students 1849(47.6%) had answered yes for any of the questions in first questioner which was followed by a detailed questioner based on MCMDM1 - VWD. Only 323 agreed to have blood testing to investigate for the bleeding tendency. Each positive case was tested for CBC, PT, PTT, ABO and PFA 100 according to standard technique. Any positive screening test for coagulation or platelet screening test was followed by more testing for relevant coagulation factor level. Those were positive only for PFA100 had been tested for platelet aggregation, electronmicroscopy, PB morphology and a sample for DNA and proteomics been collected.

The most common bleeding symptom was epistaxis found in 19.7% (3881) of all interviewed students students and was more in the positive cases 229 (43.6%) students from a total of 525 with more boys (147 out of 296, 49.7%) than the girls (82 out of 229, 35.8%, P-value= 0.002). The cutaneous symptoms were reported by 29.3% (154/525), more common in girls (102/229, 44.5%) than boys (52, 296, 17.6%, p-value<0.001). Out of the investigated cases,( 47 out of 323, 14.5 %) had high PFA100-EPI and (57 out of 323, 17.6%) Had high PFA100-ADP and 22 of these had both cartilage prolonged. We had tested 37 of the suspected cases for platelet disorders for platelet aggregation, only one case had typical features of Glanzmann's disease and 20 cases were abnormal with no clear pattern for known platelet disorders and were labeled as probable platelet disorders. We had diagnosed 8 cases with vWD.

Conclusion: The early results from our bleeding survey indicate that platelet disorders probably more common in our population than been reported els where. We are waiting the final result of laboratory tests which includes ultrastructural features, proteomics and genotyping of these cases with probable platelet diorders