ISOLATED THROMBOCYTOPENIA DURING PREGNANC Y - ETIOPATHOGENETIC STUDY AND THERAPEUTIC APPROACH IN 60 WOMEN

BACKGROUND: We analyze the etiopathogenesis and clinical and immunohem atological characteristics of 60 pregnant women with isolated thromboc ytopenia (TP) (platelet count < 150 x 10(9)/l); and the frequency of T P and hemorrhagic complications in their newborn. We suggest the thera peutic approach for each maternal TP type. PATIENTS AND METHODS: We pe rformed: clinical history, platelet count (EDTA K-3, sodium citrate, m icroscopic exam) and investigation of antiplatelet antibodies (immunof luorescence) in all pregnant women. A familial history and ultrastruct ure of platelets were studied when hereditary macrothrombocytopenia (H M) was suspected. A Levine's test of homogenicity of variances was app lied to compare the mean platelet count in each diagnostic group. A li near regression between maternal and newborn platelet counts was perfo rmed. RESULTS: In 37 thrombocytopenic women (62%) no antiplatelet anti bodies were found, and the clinical history was negative for previous TP or abnormal bleeding. Four patients (7%) were diagnosed as pseudoth rombocytopenia EDTA-mediated, and eight (13%) of HM. Finally, an autoi mmune etiology was suspected in 11 women (18%) and antiplatelet antibo dies were detected in 9. Mean platelet counts of mother with immune TP did not show statistically significant differences with other diagnos tic groups. Abnormal bleeding was not observed in any patient or newbo rn. There was no correlation between platelet counts of mothers and ne wborns. Platelet count obtained by skull bone punction led to unnecess ary caesarians in four cases. CONCLUSIONS: The frequency of immune thr ombocytopenia in pregnant women is low (18%). There is a high prevalen ce of benign TP (62%). The pseudothrombocytopenias and HM are frequent findings (20%), and special care is advisable in these cases to avoid unnecessary therapeutic procedures.