Background: Nowadays, Primary Immune Thrombocytopenia diagnosis (ITP) is based on 
identifying a platelet count < 100 × 109
/L and exclusion of other causes of thrombocytopenia. 
Currently , there are no standard tests or biomarkers to diagnose primary ITP or predict its 
prognosis and response to treatment. Objectives :Our study aims at assessing the role of High 
sensitivity C- Reactive Protein in ITP pathogenesis and in the prediction of the disease 
behavior and response to treatment. Methods: Our study was done on four groups: Group I 
consisted of 28 newly diagnosed ITP patients in whom data were recorded before and after 
treatment with corticosteroids, Group II had 10 corticosteroid responder ITP patients, Group 
III contained 10 corticosteroid resistant ITP patients, while Group IV had 18 age and sex 
matched healthy control subjects to whom the previous three groups were compared.
Results: Newly diagnosed ITP patients in our study were found to have significantly higher 
levels of High sensitivity CRP before treatment with corticosteroids compared to the same 
patients levels after treatment with corticosteroids, p value <0.001. Also, Comparing High 
sensitivity C- Reactive Protein levels in the four studied groups showed that they were higher 
in Corticosteroid resistant ITP patients (Group III) compared to the other three groups. p 
value <0.001. Conclusion: High sensitivity CRP level was found to be associated with ITP 
resistance to corticosteroid treatment, and it was found to decrease in the newly diagnosed 
patients after starting treatment by corticosteroids.