Abstract: PO1956
ANCA-Negative Small-Vessel Vasculitis with IgG4-Positive Plasma Cell Infiltration: A Case Report and Literature Review
Session Information
- Glomerular Diseases: Clinical, Outcomes, and Trials - 3
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Report
- 1203 Glomerular Diseases: Clinical, Outcomes, and Trials
Authors
- Ge, Huipeng, Xiangya Hospital Central South University, Changsha, Hunan, China
- Li, Cuifang, Xiangya Hospital Central South University, Changsha, Hunan, China
- Yuan, Qiongjing, Xiangya Hospital Central South University, Changsha, Hunan, China
Introduction
Although the histopathology was critically important for differential diagnosis between AAV and IgG4-RD, overlapping morphologies and clinical manifestations put the clinicians in a dilemma of diagnosis sometimes. Here, we described a case of ANCA negative PICG with IgG4-positive plasma cell infiltration.
Case Description
A 60-year-old male patient presented with cough for 3 months and progressive renal impairment for 8 days. He had elevated serum IgG4 level with absence of anti-neutrophil cytoplasmic antibodies (ANCA). Lung CT as shown in Figure 1. Renal biopsy showed severe tubulointerstitial nephritis (TIN) with extensive infiltration of IgG4-positive plasma cells, suggesting a diagnosis of IgG4-related kidney disease(Figure 2). However, the identification of necrotizing glomeruloneohritis and crescents forming and the absence of storiform fibrosis and obliterative phlebitis led to a diagnosis of ANCA negative renal small-vessel vasculitis. The condition was improved by using corticosteroids and cyclophosphamide at beginning.
Discussion
ANCA negative cannot exclude the diagnosis of AAV. The elevated serum IgG4 and/or abundant IgG4-positive cell infiltration can act as one of the manifestations in AAV. ANCA-negative pauci-immune crescentic glomerulonephritis (PICG) might represent an independent disease entity from ANCA positive PICG. Besides, IgG4-related disease (IgG4-RD) is an exclusive diagnosis and needs to be differentiated from vasculitis and other diseases.It is suggested that ANCA-negative PICG with elevated serum IgG4 and/or abundant IgG4-positive cell need to be further studied.
Figure 1. Lung CT in different periods.
Figure 2. Histological findings of the kidney.