Kidney Cortical Necrosis after Placental Abruption

Introduction: Renal cortical necrosis (RCN) is a rare cause of kidney failure related to obstetric complications such as sepsis, placental abruption, and eclampsia. Incidence of RCN in developed countries is low, accounting for <2% renal failure cases. Prognosis is poor due to abrupt renal function loss, but improving with wider availability of renal replacement therapy (RRT). We present a case of RCN after placental abruption with massive hemorrhage. Case Description: A 39 year old G5P2122 woman at 32w6d gestation presented for vaginal bleeding. Upon EMS arrival she was found to have placental abruption, with 0.75L of blood loss en route to the OR for emergent C-section. An additional 2L blood loss was reported intraoperatively. Her postoperative course was notable for AKI and anuria. Due to high suspicion for RCN a MRI abdomen/pelvis was obtained showing renal cortical diffusion restriction (Fig 1) suggestive of RCN. Subsequent renal biopsy showed 30% overall patchy cortical infarct and ATN, 10% IFTA, with segmental glomerular TMA-like changes (Fig 2). After 18 days she remained anuric and RRT was initiated; she remains on hemodialysis 2 months later. Discussion: Obstetric complications account for a majority of RCN cases, possibly attributed to a combination of hypoperfusion, endotoxin-endothelial injury, and vascular thrombosis. There are two histological patterns of RCN: diffuse and patchy. Differing recovery rates are associated with type of injury, with patchy RCN having a more favorable prognosis. Anuria develops in 70-80% of RCN cases. Early RRT initiation in RCN may help reduce hospital length of stay, but further studies are needed on whether it provides a mortality benefit. Prognosis remains poor with 38-56% of patients able to withdraw dialytic support several months after initiation.