From pancreatic neoplasm to increase of glands: A case report of IgG4-related disease and its spectrum

Background: IgG4-Related Diseases (IgG4-RD) represent a fibroinflammatory immune-mediated condition that might affect several organs. Due to its variable clinical presentation and differential diagnosis, early and accurate diagnosis is a real challenge. This case report aims to improve the general knowledge about IgG4-RD, enabling early and correct diagnosis, avoiding unnecessary interventions, and ensuring the best quality of life for the patient. Case Report: A 44-year-old man with diabetes mellitus and dyslipidemia presented with submandibular glands hypertrophy and a positive rheumatoid factor. He had a recent medical history of undiagnosed urinary symptoms and findings of renal nodules on an abdominal Computed Tomography. Besides that, he had undergone laparotomy with enteroanastomosis after pancreatic cancer was suspected, one year before the glands’ hypertrophy appeared. After he has been reassessed by a rheumatologist, the IgG4-RD was considered due to increase in serum IgG4, affection of a pair of salivary glands, presence of low-density areas in the renal cortex, bilaterally, affection of the pancreas and biliary ducts with dense inflammatory infiltrate and storiform fibrosis in the pancreas biopsy. The treatment with prednisone was started and the patient evolved with clinical, laboratory, and radiologic resolution after that. Conclusions: The IgG4-RD is worth reporting due to the many different clinical presentations. In this case, the diagnosis was done after years of the initial symptoms, and the patient evolved with significant improvement after the right treatment was prescribed. Corroborating to the importance of correct and early diagnosis.