Clinical Report: Misdiagnosis of IgG4-Related Autoimmune Pancreatitis

Overview

This case study highlights the misdiagnosis of IgG4-related autoimmune pancreatitis (IgG4-AIP) as acute pancreatitis in a patient with type 2 diabetes mellitus. The diagnosis was established based on elevated serum IgG4 levels.

Background

IgG4-AIP is a rare autoimmune disorder that can mimic acute pancreatitis, leading to diagnostic challenges. Its presentation may be complicated by coexisting conditions such as type 2 diabetes mellitus, which can obscure the underlying pancreatic disease.

Data Highlights

No numerical data or trial data presented in the article.

Key Findings

• The patient was initially diagnosed with acute pancreatitis but did not respond to conventional treatment.
• Serum IgG4 levels were markedly elevated at 13.8 g/L.
• Imaging findings were unremarkable, complicating the diagnosis.
• The patient showed improvement after glucocorticoid therapy, with a decrease in serum IgG4 levels.
• Measurement of serum IgG4 and integration of imaging and histopathology are important for diagnosis.

Clinical Implications

Healthcare professionals should consider IgG4-AIP in patients with type 2 diabetes presenting with recurrent abdominal pain and elevated pancreatic enzymes unresponsive to typical treatments.

Conclusion

This case highlights the need to consider IgG4-AIP in differential diagnoses for abdominal pain in diabetic patients.

Related Resources & Content

1. Frontiers in Medicine, 2026 -- IgG4-related autoimmune pancreatitis mimicking pancreatic carcinoma: a case report
2. The Journal of Clinical Endocrinology & Metabolism, 2026 -- Management of Patients with Diabetes Resulting from Exocrine Pancreatic Disorders
3. Frontiers in Medicine, 2026 -- Case report and literature review of IgG4-related autoimmune pancreatitis secondary to pancreatic involvement of IgG4-related sclerosing disease
4. The New Gastroenterologist, 2025 -- Understanding the Underlying Causes of Autoimmune Pancreatitis Symptoms
5. International consensus diagnostic criteria for autoimmune pancreatitis: guidelines of the International Association of Pancreatology - PubMed
6. Update on Autoimmune Pancreatitis and IgG4‐Related Disease
7. International consensus diagnostic criteria for autoimmune pancreatitis: guidelines of the International Association of Pancreatology - PubMed
8. Update on Autoimmune Pancreatitis and IgG4‐Related Disease