Background: Histiocytosis X, a clinically heterogeneous infiltrating disorder, is rarely associated with pregnancy. Diabetes insipidus is a common manifestation of histiocytosis X.
Case: A 27-year-old pregnant woman was diagnosed with histiocytosis X by biopsy. At 31 weeks' gestation, she developed diabetes insipidus and required treatment with intranasal 8-D-arginine vasopressin. A hypothalamic mass was noted on magnetic resonance imaging. She delivered a 363-g male at term by cesarean. Two months postpartum, after a motor vehicle accident, she developed a T6 sensory and motor deficit. An intramedullary spinal cord mass was diagnosed and surgically removed. She was treated postoperatively with radiation therapy to the spine and hypothalamus. Despite systemic chemotherapy, the disease progressed, and the patient died 18 months after delivery.
Conclusion: Pregnancy in patients suffering from histiocytosis X is rare. When pregnancy and histiocytosis X do coincide, diabetes insipidus may appear or worsen. Treatment with intranasal 8-D-arginine vasopressin does not pose risks for the fetus or for premature labor.