Pregnancy and non-pregnancy related immune thrombotic thrombocytopenic purpura in women of reproductive age

Pregnancy is a precipitating factor for immune thrombotic thrombocytopenic purpura (iTTP). We compared the clinical course and outcomes of iTTP in women of reproductive age, between those with pregnancy- and non-pregnancy-related iTTP. A review of all reproductive-aged women diagnosed with iTTP during 2010–2019 in seven university hospitals in Israel. Of 42 cases of iTTP, 12 (28.6%) were pregnancy-related. At presentation, the laboratory profiles did not differ significantly between those with pregnancy- and non-pregnancy-related iTTP, including hemoglobin (median 8.4 vs 8.0 g/dL), platelet count (12.5 vs. 11.5 X 10⁹/L); and levels of bilirubin (1.23 vs. 1.82 mg/dL), lactate dehydrogenase (1615 vs. 1701 U/L), creatinine (0.61 vs. 0.79 mg/dL) and anti-ADAMTS13 antibodies titer (75 vs. 82 U/mL). The proportions of women with renal, neurologic, or hepatic involvement were similar between the groups. Cardiac involvement was more common among those with pregnancy-related disease (25.0% vs. 3.3%, P = 0.06). The median number of courses of plasma-exchange therapy was 11 for both groups. All the women were treated with parenteral corticosteroids and the rate of adjunctive treatments did not differ between the groups (P = 0.30). Four women (one-third) with pregnancy-related disease had preeclampsia. Two women (16.7%) with pregnancy-related iTTP died during the acute episode (P = 0.07); no deaths were observed in the non-pregnancy-related group. Among reproductive-aged women with iTTP, most clinical and laboratory profiles were similar between those with pregnancy- and non-pregnancy-related disease. However, the higher rates of cardiac involvement and mortality among women with pregnancy-related iTTP highlight its challenging management.