Abstract: FR-PO130
Inflammation and Infection: An AKI Diagnostic Dilemma
Session Information
- AKI: Diagnosis and Outcomes
October 25, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Acute Kidney Injury
- 102 AKI: Clinical, Outcomes, and Trials
Authors
- Hildebrand, Hailey Victoria, University of Manitoba Max Rady College of Medicine, Winnipeg, Manitoba, Canada
- Jeon, Emily G., University of Manitoba Max Rady College of Medicine, Winnipeg, Manitoba, Canada
- Miller, Lisa M., University of Manitoba Max Rady College of Medicine, Winnipeg, Manitoba, Canada
Introduction
Glomerular full-house immune complex deposition is a characteristic finding of lupus nephritis; however, in rare cases it can occur with other glomerulopathies. We present a case of non-lupus glomerulonephritis leading to full-house immunostaining on renal biopsy.
Case Description
A 50-year-old gentleman presents with a one-month history of rash and a 20-kilogram weight loss over the past year. He denied infectious symptoms, arthralgias, or other constitutional symptoms. His examination was remarkable for palpable purpura on his legs. Initial investigations revealed an elevated creatinine 114 mmol/L, proteinuria (72mg/mmol) and hematuria. Further work-up showed low serum complements, but normal antinuclear antibodies and anti-double stranded DNA. CT imaging of the abdomen showed splenic infarcts and normal kidneys. He was started on empiric prednisone due to suspicion for an autoimmune process, but on further assessment, he was found to have poor dentition concerning for infectious endocarditis. Prednisone was stopped, and blood cultures returned positive for streptococcus mutans. He was hospitalized and started on ceftriaxone. A transesophageal echocardiogram showed vegetations on the mitral and aortic valves. A kidney biopsy was performed which showed moderate endocapillary hypercellularity with no significant tubular atrophy or interstitial fibrosis. Immunofluorescence was positive for IgG, IgA, IgM, C3, and C1q consistent with full-house immunostaining, suggesting a diagnosis of diffuse proliferative lupus nephritis. However, based on the lack of clinical manifestations and the negative lupus serology, it was suspected that this was a rare biopsy finding associated with infection-related glomerulonephritis (IRGN). He underwent CABG with atrial and mitral valve repair. Following completion of antibiotics his creatinine had normalized consistent with a resolved IRGN.
Discussion
Glomerular full-house immunostaining typically occurs in lupus nephritis; however, it can occur in other diseases including IgA nephropathy, membranoproliferative glomerulonephritis, and IRGN. It is speculated that this deposition may occur in more severe forms of IRGN due to superantigen formation. This case emphasizes the importance of clinical presentation when interpreting renal biopsy findings as rarely patients with full-house immunostaining may have a diagnosis other than lupus nephritis.