Antineutrophil cytoplasm antibody (ANCA)-associated vasculitides are rare small vessel vasculitis. In pregnancy, they are associated with significant morbidity and higher risk of adverse pregnancy outcomes [1]. The management of de novo vasculitis in pregnancy is difficult as traditional medications – high dose steroids, Rituximab or cyclophosphamide may have implications for the fetus.
We report a case of a 33-year-old female who presented with renal impairment at 12-weeks gestation (G2P1), on a background of Reynaud’s disease, superficial thrombophlebitis, and a recent presentation of olecranon bursitis. MPO-ANCA titres were elevated. A renal biopsy indicated crescentic glomerulonephritis (60% crescents) with negative immonuperoxidase staining. Successful induction of remission for ANCA-associated glomerulonephritis was achieved with prednisolone and rituximab, complicated by maternal neutropenia. A healthy boy was delivered at 36-weeks gestation, with no evidence of pathogenic transplacental-transfer of anti-MPO antibodies [2]. There was no neonatal neutropenia, and B-cells were present (6% of lymphocytes), with normal CD20 expression. At 3-months post-partum, the patient remains on a weaning dose prednisolone with no steroid-sparing maintenance agent.
There are a few case reports of de novo vasculitis during pregnancy with various treatments and outcomes, ranging from vasculitis not requiring any treatment [3], to effective treatment with prednisolone and IVIG [4], and another with prednisolone and cyclophosphamide [5]. The safety data on B-cell depleting therapies in pregnancy are lacking [6]. Studies of cynomolgus monkeys exposed during pregnancy to therapeutic doses of rituximab showed no evidence of teratogenic effects, however B-cells were temporarily reduced in the offspring [7]. A few case reports have demonstrated healthy pregnancy outcomes following maternal use for conditions such as lymphoma and rheumatoid arthritis [8], however congenital malformations (clubfoot) has been reported [9]. This is the first known case report of de novo ANCA vasculitis presenting during pregnancy successfully treated with rituximab, with nil adverse neonatal outcomes.