Abstract: TH-PO951
Double Trouble: Pulmonary-Renal Syndrome due to IgG4-RD and Myeloperoxidase-ANCA Vasculitis
Session Information
- Glomerular Trainee Case Reports
November 07, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Report
- 1202 Glomerular Diseases: Immunology and Inflammation
Authors
- Yalamarti, Tanuja, Pennsylvania hospital of UPENN, Philadelphia, Alabama, United States
- Alborzi, Pooneh, Pennsylvania Nephrology Associates, P.C., Philadelphia, Pennsylvania, United States
- Chetrit, David Alexandre, Pennsylvania Hospital, Philadelphia, Pennsylvania, United States
- Rumbaugh, Michelle Lauren, Pennsylvania Hospital, Philadelphia, Pennsylvania, United States
Introduction
IgG4-related disease (IgG4-RD) is a fibro-inflammatory condition that could be similar or overlap with ANCA-associated vasculitis (AAV).
Case Description
38- year old female with a history of inflammatory arthritis and high ANA titer, but no definite diagnosis of lupus, on hydroxychloroquine presented with chest pain, dyspnea and hemoptysis for one month. She also reported recurrent sinusitis, arthralgia, and Raynaud’s symptoms. Urinalysis revealed hemoproteinuria and cellular casts. Urine protein/creatinine was 2.8 grams. Serum creatinine rose from 0.7 to 1.08 mg/dl. CT Chest showed right upper lobe consolidation with cavitation. Anti MPO antibody was positive for >100 U/ml (0.0-9.0 U/mL). Serum complements were normal and anti-double strand DNA was negative. Initially, the patient was diagnosed with microscopic polyangiitis (MPA). However, lung biopsy noted a fibro-inflammatory lesion with elevated IgG4 positive plasma cells (20-30 per HPF) typical of IgG4-RD. Serum IgG4 level was elevated. Kidney biopsy showed membranous glomerulonephritis with cellular crescents and numerous subepithelial and intramembranous deposits that were negative for PLA2R immunofluorescence. Acute tubulointerstitial fibrosis was noted. Lack of C1q deposition and absence of tubuloreticular inclusions argued against lupus membranous disease. Patient was ultimately treated with pulse dose steroid and Rituximab, which induced remission of both IgG4-RD and MPA manifestations.
Discussion
In the literature, two entities have been described: IgG4-RD with ANCA positivity and AAV associated with increased IgG4-positive plasma cells. Our patient presetned with crescentic membranous GN and a very high anti MPO antibody. The histological features of lung biopsy however showed characteristics of IgG4-RD. Although membranous GN is reported both with AAV and IgG4- RD, it is not a typical renal biopsy finding of either of those diseases. Corticosteroids are the first line therapy in IgG4-RD without any adjuant immunosuppressive therapy. However, because of ANCA positivity and the presence of crescentic GN, our patient was treated with rituximab as well in addition to the steroids. We need to consider the possibility of IgG4-RD in patients with AAV and vice versa for appropriate treatment plan and prognosis assessment.