Thrombotic thrombocytopenic purpura: report of fourteen cases--occurrence during pregnancy and response to plasma exchange.

Thrombotic thrombocytopenic purpura (TTP), a syndrome of diverse etiology probably related to factors regulating platelet-vessel wall interaction, is predominantly a disorder of women. We report our experience with 14 patients in an 11-year period. Thirteen were female and aged between 25-69 years. Four were postmenopausal, and of the nine premenopausal women three were pregnant, one was immediately postpartum, and three were taking estrogen-containing oral contraceptives. A review of the literature confirms the two to one female/male preponderance and that TTP is reported in 56 women who are pregnant or recently postpartum. While this association with possible hormonal events has been noted, it has previously received little comment. We stress the similarity between TTP and some occurrences of preeclamptic toxemia, and that this may suggest not only a common etiology but that therapeutic attempts should be similar. While no single therapeutic modality is universally successful, our experience is that plasma exchange is the most effective, with five of seven patients so-treated obtaining prolonged remission; four of five patients responded to splenectomy and corticosteroids, but one died of infection postoperatively. Five patients, including two treated exclusively with antiplatelet aggregating agents, died without achieving remission. The frequency of successful therapy is not changed by the concurrent pregnancy, but the fetal loss is high. There does seem to be an increased risk of recurrence of TTP in a subsequent pregnancy, and this might be considered when counseling premenopausal patients who have achieved remission of TTP.