Impaired Platelet Aggregation to Adenosine Diphosphate (ADP) Agonist in National Blood Centre, Malaysia

Bleeding symptoms are common in population. However, it is difficult to assess the clinical relevance of mild bleeding disorder. One of the causes of mild bleeding disorder is due to platelet function defects either related to abnormality in the membrane receptor on platelet or its signal transduction pathway. Platelet adenosine diphosphate (ADP) receptor, namely P2Y12 played a central role in platelet activation. The receptor is important as it is one of the therapeutic targets for antithrombotic drugs. The objective of this study was to determine causes of impaired platelet aggregation to ADP agonist, socio-demographic and clinical characteristics among patients in National Blood Centre. Data were recorded from 1st January 2009 to 31st May 2011. The results showed 32 (13%) out of 251 platelet aggregation test performed had impaired platelet aggregation to ADP (20 μM) using local cut off point of 65%. Out of those, 16 (50%) possibly had inherited ADP receptor dysfunction. Sixteen (50%) patients had secondary causes of impaired platelet aggregation to ADP either associated with von Willebrand disease (vWD), glycogen storage disease (GSD) or acquired platelet dysfunction with eosinophilia (APDE). Majority of patients were Malays (78.1%), with slight female preponderance (59.4%) and age ranged from 1-44 years old. Results obtained from this study could serve as a reference for a national registry on mild bleeding disorder related to platelet function defects. This knowledge is also important for future research related to platelets as biomarkers or potential therapeutic application in various diseases.