Predictors of idiopathic thrombocytopenic purpura in pregnant women presenting with thrombocytopenia.

OBJECTIVE

Idiopathic thrombocytopenic purpura (ITP) and gestational thrombocytopenia (GT) are common causes of thrombocytopenia during pregnancy. Despite an ever-increasing experience with these disorders, differentiation between the two entities still remains a diagnostic challenge. The current study attempted to identify the antenatal predictors of ITP for pregnant women.

METHODS

Between January 1999 and June 2005, a total of 58 pregnant women with a presumptive diagnosis of either ITP or GT were recruited for the study. All of them had platelet counts of less than 100 x 10(9)/L. The predictors of ITP were evaluated by comparison between the two disorders.

RESULTS

The detection of thrombocytopenia prior to 28 weeks of gestation and platelet counts <50 x 10(9)/L at its diagnosis remained independently predictive of ITP (P<0.001 and P=0.004, respectively). The combined analysis of these two factors provided a 96.0% sensitivity and a specificity of 75.8%.

CONCLUSION

The onset time of thrombocytopenia and platelet count at its presentation remain the strongest predictors of ITP for pregnant women. The combination model using these factors may be useful for the early prediction of ITP.