Pregnancy and thrombosis: Adrenal vein thrombosis. A retrospective descriptive study of 14 cases

Adrenal vein thrombosis during pregnancy is a rare thromboembolic event but is not exceptional. The objective of this study was to described the symptoms, diagnosis, treatment and follow-up of patients with this condition.

This was a retrospective descriptive study of 14 cases (13 patients, one recurrence) that occurred in the three university maternity hospitals in Lyon (France) from 2008 to 2016.

Adrenal vein thrombosis occurred exclusively in the third trimester (gestational age > 28 weeks), with most patients presenting unilateral lumbar pain (13/14 cases, 93%) and vomiting (8 cases, 57%), mimicking renal colic. To establish the diagnosis, all patients were examined by abdominal CT and all but three (79%) by abdominal ultrasonography. Ten patients (71%) were treated by low molecular weight heparin and the remaining four (29%) by unfractionated heparin. The delay between presentation and diagnosis, and thus before treatment was initiated, was greater than 24 h in 50% of cases. Thrombosis occurred predominantly (11 vs 3 cases) on the right adrenal vein. Labor inducing or cervical ripening agents were used after temporarily interrupting treatment for 9/14 patients (64%). Epidural anesthesia was possible for 11 patients (79%) and 2 (14%) had postpartum hemorrhage. Eleven patients received hemostatic function investigations with anomalies detected in four cases (36%). One of the six patients (16%) who had a second full-term pregnancy during the study period had a contralateral recurrence.

Adrenal vein thromboses are rare events requiring curative anticoagulant therapy and labor management to minimize the risk of hemorrhage. Patients should receive thromboprophylaxis for subsequent pregnancies and a full thrombophilia investigation.