Abstract: PUB204
The Enigmatic Case of Lupus Nephritis: Negative Antinuclear Antibodies (ANA) in a Sea of Symptoms
Session Information
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Brennan, Meghan, Prisma Health Midlands, Columbia, South Carolina, United States
- Lucas, Bennett Alan, University of South Carolina School of Medicine Columbia, Columbia, South Carolina, United States
- Huber, Michael, Prisma Health Midlands, Columbia, South Carolina, United States
- Giovannini, David, Prisma Health Midlands, Columbia, South Carolina, United States
Introduction
Immune complex glomerulonephritis (IC-GN) is a renal disorder characterized by granular immunoglobulin deposition in the glomeruli, with or without concomitant immune complex deposition. This condition most commonly occurs as a manifestation of SLE, affecting more than 80% of patients at some point during their disease course. Typically, this is in the setting of a positive ANA and positive anti-dsDNA. Biopsy with immunofluorescence is needed to confirm the diagnosis prior to initiating immunosuppressive therapy with pulse steroids for class III or IV disease. This case demonstrates a patient diagnosed with lupus nephritis class III despite initially negative screening ANA and anti-dsDNA.
Case Description
A 36-year-old female presented to the emergency department for fatigue, myalgias, and chest pain. Troponin levels were elevated, and she was admitted for possible myocarditis. Further investigation revealed intermittent fevers, pancytopenias, and muscle weakness with elevated CK prompting a muscle biopsy showing necrotizing myopathy. She also developed acute renal failure with sub-nephrotic range proteinuria. Initial serological tests, including ANA, anti-dsDNA, lupus anticoagulant, and beta-2 glycoproteins were normal. Initial kidney biopsy was also inconclusive. Because her clinical picture fit so closely with SLE with focal lupus nephritis, she underwent repeat serological testing and repeat kidney biopsy, which this time revealed sclerosing glomerulonephritis with “full house” immune complex deposition. She was started on mycophenolate and pulse dose steroids even before serology testing returned positive. The patient was arranged with close outpatient follow up with nephrology and rheumatology, and after discharge, her repeat ANA and anti-dsDNA returned positive with high titers. On one month follow up, Cr and GFR normalized, and muscle strength improved.
Discussion
The 2019 EULAR/ACR criteria for SLE include positive ANA as an entry criterion and then uses a weighted criteria including anti-dsDNA to determine classification. This case demonstrates a unique presentation of biopsy-confirmed IC-GN consistent with focal lupus nephritis class III despite negative ANA and negative anti-dsDNA testing, underscoring the challenges of diagnosing SLE within current guidelines and the necessity to maintain a high clinical suspicion in the face of negative tests.