Abstract: PO1527
Features and Outcomes of Patients with C1q Nephropathy in the NEPTUNE and CureGN Cohorts: Comparisons to Minimal Change Disease and Focal Segmental Glomerulosclerosis
Session Information
- Glomerular Diseases: Clinical Features and Outcomes in Nephrotic Syndromes and Complement-Mediated Diseases
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1203 Glomerular Diseases: Clinical, Outcomes, and Trials
Authors
- Wenderfer, Scott E., Baylor College of Medicine, Houston, Texas, United States
- Larkina, Maria, University of Michigan, Ann Arbor, Michigan, United States
- Bekheirnia, Mir Reza, Baylor College of Medicine, Houston, Texas, United States
- Cassol, Clarissa Araujo, Arkana Laboratories, Little Rock, Arkansas, United States
- Avila-Casado, Carmen, University Health Network, Toronto, Ontario, Canada
- Barisoni, Laura, Duke University, Durham, North Carolina, United States
- Smoyer, William E., Nationwide Children's Hospital, Columbus, Ohio, United States
- Mariani, Laura H., University of Michigan, Ann Arbor, Michigan, United States
Background
Predominant immunostaining for C1q distinguishes a subset of patients with primary glomerular disease. C1q nephropathy (C1qN) has been proposed but not universally accepted as a distinct glomerular disease. This study describes clinical characteristics and short-term outcomes of patients meeting the provisional CureGN definition of C1qN, including comparisons to patients with minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS) without C1qN.
Methods
MCD and FSGS patients with C1qN were identified from the Cure Glomerulonephropathy Network (CureGN) and NEPTUNE cohorts. Comparisons were made to MCD and FSGS patients without C1qN, based on age, disease, and time since kidney biopsy, using 5-to-1 matching. We performed cross-sectional analyses of clinical and treatment data at enrollment and a longitudinal analysis of disease course.
Results
A total of 42 patients met the provisional CureGN definition for C1qN (16 adults >18yo, 11 teens 12-18yo, and 15 children <12yo), including 15 with MCD and 27 with FSGS. Those with C1qN were more commonly female (60 vs 49%, p=0.2) and black (34 vs 27%, p=0.4). At enrollment, those with and without C1qN had comparable kidney function (eGFR 90 vs 88 mL/min/1.73m2, p=0.8). Individuals with C1qN were equally likely to have been treated with steroids or other immunosuppressive therapy (76 vs 81%, p=0.4) and to have ever achieved complete remission of proteinuria (defined as uPCR <0.3) (54 vs 65%, p=0.2). Median time to last follow-up was 3.1 yrs (IQR 1.9, 4.4) from enrollment and 4.8 yrs (IQR 3.3, 6.5) from biopsy date. While proportions with kidney failure were higher for FSGS compared to MCD (14 vs 1%, p=0.01), they were similar between patients with and without C1qN (7 vs 10%, p=0.6). There was a trend towards steeper GFR slope in C1qN patients (-4.8 vs -0.2 mL/min/yr, p=0.06).
Conclusion
FSGS and MCD patients with and without C1qN have comparable demographics and short-term outcomes in CureGN and NEPTUNE. Outcomes do not appear to be biased by differences in immunosuppressive therapies. Further interrogation of genetic and molecular profiles between patients with and without C1q immunostaining on biopsy may be more informative.
Funding
- Private Foundation Support