Last update:
06-Jul-2016

OBJECTIVE Differing dominant T-cell and B-cell pathophysiological mechanisms may be involved in immune thrombocytopenic purpura (ITP). In this study phenotype analysis was made of peripheral blood lymphocyte abnormalities and correlation explored between circulating lymphocyte subtypes and age, sex, serological findings and disease course.

METHOD A retrospective study was conducted of 20 adults and 3 children with ITP whose lymphocyte phenotype analysis data were compared with those of 20 age- and sex-matched healthy volunteers.

RESULTS No differences were observed between patients with well-responding and relapsing ITP. Negative correlation was demonstrated between CD20⁺/CD23⁺ B-cell levels and the number of relapses per year and positive correlation between high CD19⁺ and CD22⁺ levels and the need for splenectomy. CD5⁺ and CD7⁺ T-cell levels were inversely related with the detection of ANA and IgG anti-cardiolipin autoantibodies. Patients aged above 60 years had significantly lower levels of CD2⁺ and CD3⁺ T-cells and higher levels of CD5⁺/CD19⁺ co-expression. Finally, CD19⁺, CD20⁺, CD22⁺ B-cell levels, CD19⁺/CD79b⁺, CD19⁺/CD25⁺ and CD20⁺/CD23⁺ markers, and Fmc7⁺/CD11c⁺ co-expression were all significantly raised in patients with ITP.

CONCLUSIONS B-lymphocyte abnormalities and age-related T-cell defects may be implicated in the pathogenesis and outcome of ITP.

Key words: Immune thrombocytopenic purpura, Immunophenotype, ITP, Thrombocytopenia.