Abstract: TH-PO701
"Finding the Bright Side": A Case Series of Spontaneous Remission in NELL1 Membranous Nephropathy
Session Information
- Glomerular Diseases: Case Reports
November 02, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Trials
Authors
- Bucaloiu, Ion D., Geisinger Health, Danville, Pennsylvania, United States
- Sankar, Lakshna, Geisinger Health, Danville, Pennsylvania, United States
- Kalra, Kartik, Geisinger Health, Danville, Pennsylvania, United States
Introduction
Neural tissue encoding protein with EGF- like repeats (NELL1) has been identified as a target antigen in membranous nephropathy (MN). It can be primary or associated with malignancies, stem cell transplant, de novo in kidney transplant, drugs, autoimmune diseases and infections.
Case Description
Four patients of Caucasian origin with age ranging from 50 - 71 years presented with nephrotic syndrome (Table 1). At presentation, all had urine protein creatinine ratios above 5 g/g creatinine. Immunological work up was negative. Kidney biopsy was positive for NELL1 associated MN. Infectious work up including hepatitis panel, human immunodeficiency virus (HIV) and rapid plasma regain (RPR) were negative. Screening for underlying malignancy including computed tomography (CT) of chest, abdomen and pelvis, pap smear, mammogram and colonoscopy was unremarkable. Careful review of home medications list showed no indigenous medications except for one patient who was on lipoic acid for a duration of 1 year which was stopped after the diagnosis of NELL1 MN. Supportive care such as renin-angiotensin blockade (RAAS) and diuretics were initiated with periodic monitoring of renal functions and proteinuria (Table 1). All 4 patients went into remission within 3 – 6 months.
Discussion
Spontaneous remission (30% of the patients) is a well-known characteristic of MN. Patients with persistent nephrotic range proteinuria are at risk of progression to end stage kidney disease and may require immunosuppression therapy. Several studies showed that a higher percentage of NELL1 MN cases are associated with malignancies (up to 30%) compared to MN associated with other antigens (PLA2R and THSD7A). Our case series suggests that NELL1 MN without underlying malignancy might experience spontaneous remission without need for immunosuppression. After excluding malignancy, a conservative strategy including maximizing RAAS blockade with serial monitoring of kidney function and proteinuria for 3-6 months may be appropriate in NELL1 MN.
Table 1: Clinical characteristics of NELL1 membranous nephropathy
| Patients | Age, gender and demographics | Creatinine in mg/dL (reference range 0.5 – 1 mg/dL) | Proteinuria (Urine protein creatinine ratio in mg/g) | Albumin in g/dL (reference range 3.8 – 5 g/dL) | Serum PLA2R IFA (Immunofluorescence) | Renal biopsy | Supportive care (RAAS blockade +/- diuretics) | Time to remission Complete / Partial |
| Case 1 | 50-year-old Caucasian female | 0.9 | 5200 | 3.5 | Negative | Membranous glomerulopathy, NELL1 positive; PLA2R, THSD7A, EXT 2 were negative. | Lisinopril 30 mg daily, cessation of lipoic acid | 6 months |
| Case 2 | 68-year-old Caucasian male | 1.2 | 6235 | 3.2 | Negative | Membranous glomerulopathy, NELL1 positive; PLA2R and THSD7A were negative. | Losartan 100 mg daily | 2 months |
| Case 3 | 70-year-old Caucasian male | 1.0 | 9124 | 2.7 | Negative | Membranous glomerulopathy, NELL1 positive; PLA2R and THSD7A were negative. | Losartan 100 mg daily, Lasix 40 twice daily | 3 months |
| Case 4 | 71-year-old Caucasian female | 0.8 | 17,245 | 2.9 | Negative | Membranous glomerulopathy, NELL1 positive; PLA2R, THSD7A, SEMA3B and EXT2 were negative. | Losartan 25 mg daily, Torsemide 20 mg daily | 6 months |