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Abstract: FR-PO863

Native Renal Biopsy D4 Postpartum

Session Information

Category: Women's Health and Kidney Diseases

  • 2200 Women's Health and Kidney Diseases


  • Golbus, Alexa E., Medical University of South Carolina, Charleston, South Carolina, United States
  • Freidin, Natalie T., Medical University of South Carolina, Charleston, South Carolina, United States

aHUS is a thrombotic microangiopathy caused by overactivation of the alternative pathway of complement activation. aHUS can be diagnosed on renal biopsy, and treatment with eculizumab should begin as soon as possible in order to prevent progression to ESRD. However, evidence regarding appropriate timing of renal biopsy in pregnancy and the immediate period postpartum is not clear.

Case Description

Following vaginal delivery complicated by postpartum hemorrhage and subsequent dilation and curettage with an estimated blood loss of 1.5 L, a 33-year-old female developed atypical hemolytic uremic syndrome and AKI with serum creatinine to 9.4 mg/dl (baseline 0.6). PLEX was initiated and CT-guided renal biopsy 4 days postpartum demonstrated aHUS with cortical necrosis, which was subsequently treated with eculizumab. In the days following renal biopsy, our patient had abdominal and flank pain and a renal subcapsular hematoma was found on CT, measuring 5.9 x 4.4 cm, but self-resolved without further complication. 18 months later Cr recovered to 1.1 mg/dl.


In patients with p-aHUS not treated with eculizumab, 62% reach ESRD within a month, and over 75% ultimately reach ESRD. Eculizumab, a complement C5 inhibitor, significantly reduces the risk of progression to ESRD and need for kidney transplantation. Therefore, early identification in cases of aHUS is important. While pregnancy and the postpartum period are thought to increase risk of complications in renal biopsy including bleeding and hematoma, due to increased blood flow through the kidneys, there is not a consensus regarding appropriate timing of biopsy. A systematic review of renal biopsy in pregnancy and postpartum demonstrated a 7% incidence of complications in pregnant patients, with the majority of serious adverse events occurring in weeks 23-26. Notably, postpartum patients had no severe adverse events, and complications, which occurred in 1% of cases, were mild and included microhematuria and hematoma. While there remain no clear guidelines on timing and specific indication for biopsy in this patient population, timely biopsy in our patient allowed for early initiation of treatment with eculizumab. Renal biopsy in pregnant and postpartum patients is an area lacking research and clear guidance and is likely underperformed due to the perceived risk, whether real or overstated.