[Neonatal consequences of maternal autoimmune thrombocytopenic purpura]

To describe the clinical characteristics in newborns of mothers with autoimmune thrombocytopenic purpura (ATP), as well as to evaluate the mother's platelet count in the prediction of the neonatal thrombocytopenia.

We included 33 mothers with their 40 newborns, who were classified in four groups: Group I: ten newborns whose mothers suffered of chronic autoimmune thrombocytopenic purpura who during the pregnancy remained in haematologic remission. Group II: nine newborns whose mothers were splenectomized for ATP in the preceding treatment but without symptoms during the actual pregnancy. Group III: eleven newborns whose mothers had chronic ATP and splenectomy, but during the actual pregnancy showed purpuric activity. Group IV: Ten newborns whose mothers had acute ATP during actual gestation with clinical data for bleeding.

None of the newborns belonging to the group I presented thrombocytopenia. Mean platelet count at birth was 150 x 10(9)/L in group I, 124 x 10(9)/L u/L in group II, 47 x 10(9)/L in group III and 89 x 10(9)/L in group IV. There were significant differences between the focus groups (p < .01). The mean platelet count in groups III and IV, presented the lower values between days three and fourteen of postnatal age. In these same groups, we observed more morbility related with haemorrhagical activity or infectious complications derived from treatment with steroids. The presence of maternal thrombocytopenia was associated in the 86.7% of the cases with platelet count < 100 x 10(9)/L at the time of birth.

The maternal background with low probability of fetal or neonatal thrombocytopenia included mothers with inactive ATP and the antecedent of splenectomy. On the contrary, the greatest probability of fetal and neonatal affection happens when the mother presents active chronic ATP and the previous antecedent of being refractory to the treatment with splenectomy or when acute ATP occurred during pregnancy.