Abstract: TH-PO559
Proliferative Glomerulonephritis with Monotypic Immunoglobulin Deposits (PGNMID) and Preeclampsia
Session Information
- Glomerular Diseases: From Inflammation to Fibrosis - I
November 02, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1401 Glomerular Diseases: From Inflammation to Fibrosis
Authors
- Kumar, Mukaish, Lehigh Valley Health Network, Allentown, Pennsylvania, United States
- D'Agati, Vivette D., Columbia University Medical Center, New York, New York, United States
- Maynard, Sharon E., Lehigh Valley Health Network, Allentown, Pennsylvania, United States
Introduction
We report the case of a pregnant woman presenting with hypertension, nephrotic range proteinuria and hematuria. Kidney biopsy revealed glomerular thrombotic microangiopathy (TMA) and underlying PGNMID with IgG1-k deposits.
Case Description
A 33-year-old woman presented at 21 weeks’ gestation with new-onset hypertension. She had a history of prior preterm preeclampsia and obesity s/p gastric sleeve surgery. Physical exam was normal except for blood pressure 141/111 mmHg. Kidney function was normal. UA showed hematuria and proteinuria, with UPCR of 3.7 g/day. Fetal ultrasound showed severe fetal growth restriction (FGR). ANA, Anti-dsDNA, Anti-PLA2R Ab were negative, and complements were normal. She had persistent proteinuria and microscopic hematuria on multiple UAs from 5 years prior to pregnancy.
Kidney biopsy was done at 23 weeks’ gestation to evaluate for glomerular disease vs. preeclampsia. Light microscopy showed glomerular endotheliosis with a membranoproliferative pattern, consistent with preeclampsia. IF showed mesangial and segmental glomerular capillary wall staining for IgG1 and k with negative λ, consistent with proliferative glomerulonephritis with monotypic IgG-k deposits (PGNMID). SPEP and immunofixation was negative for a monoclonal protein. Testing for HBV, HCV, and HIV was negative.
At 24 weeks, labor was induced for worsening transaminitis. Due to severe FGR, neonatal resuscitation was not attempted. At 3 weeks postpartum, her BP and proteinuria improved (UPCR 1.3g/day). Kidney function remained normal.
Discussion
To our knowledge, this is the first reported case of PGNMID with preeclampsia. There is 1 report of PGNMID in pregnancy, but without preeclampsia. As in our case, IF showed IgG1- k, and there was no monoclonal protein detected.
PGNMID was first described in 2004 as an endocapillary proliferative or membranoproliferative glomerulonephritis related to monoclonal IgG deposition. Most (70%) patients with PGNMID do not have a detectable circulating monoclonal protein in the serum or urine. In such cases, treatment directed at a hypothesized underlying clone may still be considered.
In our patient, preeclampsia complicated the clinical presentation and obscured the pathologic findings of PGNMID. Kidney biopsy assisted in confirming the diagnosis of preeclampsia, allowing appropriate management when preeclampsia progressed.