What is ADP (Adenosine diphosphate) fibrinogen test?
ADP, formed by Ib receptor, acts on IIb IIIa receptor through fibrinogen and causes aggregation.
In vWD and Bernard Soulier disease (Ib defect), if you add ADP, aggregation would take place and test will be normal as it acts on IIb IIIa receptor.
In glanzmann thrombasthenia, the IIb IIIa receptor is deficient. ADP can not act on the receptor, if added. That's why, the test becomes abnormal.
Therefore, the test is normal in vWD, Bernard soulier disease and abnormal in glanzmann thrombasthenia.
Explained by Abhishek Shukla