Three Cases of FSGS and Thrombotic Microangiopathy Presenting in Pregnancy: Experience in a Single Center

Introduction: The association between pregnancy and focal segmental glomerulosclerosis (FSGS) is not fully understood. Symptoms of FSGS such as proteinuria, edema, and HTN are also seen clinically with preeclampsia. We present three cases at an academic medical center with FSGS on biopsy after presenting with preeclampsia with severe features. Case Description: The first is a 33F G1P0 presenting at 27w0d with HTN, edema, AKI, and proteinuria of 13,672mg that did not improve post-delivery. Serological GN workup negative. Kidney biopsy (bx) suggested primary FSGS with interstitial fibrosis and tubular atrophy (IFTA). She was treated with 16 weeks of prednisone, SGLT-2i, and ARB. Remission achieved in 6 months. Genetic testing negative. The second is a 25F G1P0 with AKI, hypertension, edema, and proteinuria of 10,472mg without improvement with delivery. She underwent kidney bx which showed FSGS, chronic thrombotic microangiopathy (TMA), minimal IFTA. Proteinuria resolved spontaneously. Our third is a 26F G1P0 with T2DM, HTN, PCOS who presented at 33w3d with HTN and 24h urine protein of 4578mg. Kidney bx showed acute TMA and FSGS. Testing found elevated complement factor I and factor B with negative genetic testing. She is currently being treated with ravulizumab-cwvz. Discussion: These cases illustrate the heterogeneity of patients with FSGS / TMA in pregnancy. The most common finding in kidney biopsies of pregnancy is FSGS. Our center found significant heterogeneity in these patients with different representative outcomes. Pregnancy may be a trigger of glomerular disease and preexisting glomerular disease increases risk of preeclampsia. Further studies are needed to better risk-stratify patients with preeclampsia to guide management of the pregnancy and glomerular disease. Summary Of Cases - Patient A B C History 33F G1P0 presented at 27w0d, no risk factors 25F G1P0 presented 27W06D, no risk factors 26F G1P0, DM, HTN, PCOS, presented at 33W3D BP (Max) 159/97 151/103 172/89 Proteinuria (mg) 13672 10472 4578 Peak Creatinine (Baseline Creatinine) 1.23 (0.53) 1.26 (0.9) 0.89 (0.54) Albumin (min, g/dL) 2.4 2.5 2.6 Renal Pathology FSGS, no active TMA, minimal IFTA FSGS, chronic TMA, minimal IFTA Focal acute and chronic TMA, FSGS, diabetic nephropathy w/ nodular glomerulosclerosis, mild IFTA Placental Pathology Small placental weight, focal infarction Small placental weight, no specific pathological dx. Small placenta, decidual vessels with mild hypertrophic change vasculoapthy, fibrinoid degeneration, and perivascular chronic inflammation, subchorial hematomas, unremarkable fetal membranes Complement C3, C4 WNL Complement HUS panel pending. C3 and C4 WNL C3 and C4 WNL, elevated factor I and factor B levels. Genetics ALG-1 Mutation, none associated w/ FSGS Negative Negative Treatment 16W steorids, MRA, SGLT-2i, ARB Supportive Care Ravulizumab-cwvz, SGLT2i-2i, ARB Outcome Remission achieved in 6 months with therapy Rapidly downtrending PCR. UA 3 month later WNL. Treatment underway