Clinical Significance of Positive Platelet Immunofluorescence Assay in Adult Immune Thrombocytopenia: a Cross Sectional Study

Immune thrombocytopenia is a hematologic disorder characterized by low platelet count and variable bleeding manifestations due to immune-mediated platelet destruction and/or suppression of platelet production. This study was performed to evaluate characteristics and clinical presentations of adult patients with immune thrombocytopenia and to explore the clinical value of platelet antibodies assay among Iranian patients. Patients and In this cross sectional case series study 46 adult patients with immune thrombocytopenia and platelet count of < 100 x 109/L, referred to the Taleghani Medical Center, Tehran, Iran, between 2007 and 2009 were evaluated. The platelet autoantibodies were measured by means of indirect platelet suspension immunofluorescence test. According to our results, 7 patients (15.2%) displayed positive platelet antibody assay. There was a significant negative correlation between platelet count and antibody level (r = - 0.59; p <0.001). Additionally, a positive correlation between platelet count and patients’ age (r = 0.302; p =0.042) was detected. Twenty patients (56.5%) were symptomatic at presentation and the most common bleeding signs were petechia, purpura and epistaxis. Results indicated no significant correlation between increased platelet antibody level and bleeding manifestations except for hematuria (r = 0.435; p =0.02) and epistaxis (r = 0.382; p =0.015). Patients with positive antibody assay have been reported to have more bleeding symptoms and lower platelet counts. In our series, the increased antibody level was correlated with thrombocytopenia. However, among our patients with positive antibody assay no significant difference in bleeding manifestations was observed except for hematuria and epistaxis. Keywords: Immune thrombocytopenia; platelet, autoantibodies, platelet immunofluorescence test.