Abstract: PO0237
Tubulointerstitial Lupus Nephritis with Coexisting Renal Limited IgG4 Disease
Session Information
- AKI Mechanisms - 3
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Report
- 103 AKI: Mechanisms
Authors
- Saleem, Bushra Z., Rutgers The State University of New Jersey, New Brunswick, New Jersey, United States
- Saro-Nunez, Lilian, Rutgers The State University of New Jersey, New Brunswick, New Jersey, United States
- Ahmed, Ayesha, Rutgers The State University of New Jersey, New Brunswick, New Jersey, United States
- Siddiqui, Hammad, Rutgers The State University of New Jersey, New Brunswick, New Jersey, United States
Introduction
The classic pattern of Lupus Nephritis (LN) is an autoimmune complex mediated glomerulonephritis. Rare cases have been described with predominant tubuluinterstitial nephritis (TIN) with tubulointerstitial immune deposits in the absence of significant glomerular lesions. We describe a patient with such pattern of disease along with co- existing renal limited IgG4 related disease (IgG4 RD).
Case Description
27-year- old man with no past medical history presented with fever, malaise and cough for 3 days. It was associated with occasional epistaxis and weight loss for 3 months. He denied any rash, joint pains, oral ulcers or photosensitivity. On admission he was noted to have creatinine of 7.2 mg/ dl with eGFR of 9ml/min/1.73m2. His UA showed 3 + blood, protein to creatinine ratio of 1.61 microgram/ mg and microalbumin to creatinine ratio of 334 microgram/ mg. His pertinent positive blood work includes ANA titer of 1:1280, complements levels C3 < 26.3 and C4 < 7.9. He underwent a renal biopsy that showed immune complex mediated chronic active interstitial nephritis and increased IgG4 positive plasma cells, minimal glomerular alterations with rare mesangial deposits. Full house pattern was observed in tubules on immunoflorence. Lymph node FNA performed did not demonstrate increased IgG4 levels, however his serum IgG4 levels returned high at 205 mg/dl. He was diagnosed with Tubuluinterstitial Lupus Nephritis with renal limited IgG4 disease. He was started on high pulse dose steroid followed by taper and mycophenolate mofetil (MMF). He demonstrated good response with improvement in proteinuria, complement levels and ANA titers. His serum creatinine improved to 2.6 mg/ dl at 6 months.
Discussion
A very few cases of lupus TIN without glomerular involvement are described in the literature and management options remain unclear. The most frequent renal manifestations of IgG4-RD are TIN, membranous glomerulonephropathy and obstructive nephropathy due to retroperitoneal fibrosis. The presence of an overlap of LN with IgG4 RD has been reported in very limited number that our patient had. Our patient responded well to the treatment with MMF and Steroids. However, there is need to describe and study more such cases to delineate management protocols. We continue to follow him in clinic and monitor him for involvement of other organ system.