The assessment of 18F-FDG PET/CT in IgG4-related disease: Case report and review of the literature

Abstract

Immunoglobulin G4-related disease (IgG4-RD) is easily misdiagnosed. We report a case of IgG4-RD, whose main complaint was swollen eyelids, revealed by 18F-fluorodeoxyglucose (18F-FDG) positron-emission tomography/computed tomography (PET/CT) and confirmed by pathological analysis from the submaxillary nodes. A 49-year-old woman complained about a bilateral swollen eyelid with blurred vision for 2 years. An enlarged submandibular lymph node was found during a physical examination. Head-enhanced magnetic resonance imaging (MRI) showed that the nasopharyngeal soft tissues were thickened, and the bilateral cervical lymph nodes were enlarged. A nasopharyngoscopy and tissue biopsy indicated chronic inflammation. 18F-FDG PET/CT was taken to eliminate malignant tumor metastasis, and the results suggest autoimmune disease. A biopsy of submandibular lymphatic nodes was taken, and the immunohistochemical staining showed IgG4-positive cells. Finally, IgG4-RD was diagnosed with elevated serum IgG4. The diagnosis of IgG4-RD is based on a comprehensive judgment of clinical symptoms, serum IgG4 levels, imaging studies, and pathological evidence. Ophthalmologists should be aware of the general conditions of patients who complain of unexplained ocular swelling, and 18F-FDG PEC/CT is strongly recommended. Compared with histopathologic examination, 18F-FDG PEC/CT can display changes in morphology and metabolism in involved organs and is noninvasive. It can be helpful in detecting, diagnosing, characterizing, and monitoring the response of the IgG4-RD.