Background:
Primary Immune thrombocytopenia (ITP) is an autoimmune disease characterized by both platelet destruction and impaired platelet production.
Vitamin D regulates the growth and differentiation of various cells of the immune system through acting on vitamin D receptors (VDRs) expressed on these immune cells.
Studies have demonstrated the role of VDR polymorphisms in the development of various autoimmune diseases.
Aim of the Work To find the correlation between vitamin D receptor gene polymorphism and outcome in primary and resistant immune thrombocytopenic patients under Eltrombopag therapy.
Study design: Exploratory comparative cross-sectional study.
Results :
BsmI VDR polymorphism with its different alleles was detected in all our studied patients either respondent or resistant ones. BB allele was detected in 11 patients (73.3%) in responder group while it was detected in 2 patients (13.3 %) in resistant group with high significant difference p value (0.003).
Apal VDR polymorphism and FokI VDR polymorphism didn't reveal any statistically significant difference when comparing both groups with p value (1.000) and (P > 0.05) respectively although detected in all patients.
 Conclusion :
Our study suggests that Bsml polymorphism has an impact on ITP patients regarding treatment response as we detected BB allele more frequently in ITP responders while bb allele was more detected in resistant ITP patients.
While Apal VDR polymorphism and FokI VDR polymorphism didn't reveal any statistically significant relation to treatment response when comparing both groups.