# IgG4-Related Disease: A Case Series Highlighting Diverse Clinical Manifestations and Treatment Outcomes

## TL;DR

This paper presents three cases of IgG4-related disease with varied symptoms and successful treatment using rituximab, highlighting the importance of accurate diagnosis.

## Contribution

The study contributes by showcasing diverse clinical presentations and effective treatment outcomes in IgG4-related disease.

## Key findings

- Three patients with IgG4-RD showed varied symptoms including gland swelling and lymphadenopathy.
- All patients responded well to rituximab treatment, showing clinical and radiological improvement.
- The cases emphasize the need to consider IgG4-RD in multisystem and atypical conditions.

## Abstract

IgG4-related disease (IgG4-RD) is a systemic immune-mediated fibroinflammatory condition characterized by tumor-like swelling of affected organs, lymphoplasmacytic infiltration enriched with IgG4-positive plasma cells, and variable degrees of fibrosis. We present three cases of IgG4-RD with diverse clinical presentations, highlighting the diagnostic challenges and management approaches. Our cases include a 45-year-old female with lacrimal and salivary gland involvement mimicking Sjögren's syndrome, a 77-year-old male with pancreatic mass, mesenteric vasculitis, and intra-abdominal lymphadenopathy initially suspected as pancreatic cancer, and a 75-year-old male with diffuse lymphadenopathy, initially thought to be lymphoma. All patients were successfully treated with rituximab with good clinical and radiological responses, emphasizing the importance of considering IgG4-RD in the differential diagnosis of conditions with multisystem involvement and atypical presentations.