Immunoglobulin G4 (IgG4)–related disease is known to mimic multiple malignancies and always poses a diagnostic challenge. We report a case of a 20-year-old young man, who presented with unexplained recurrent episodes of fever and pain abdomen. 18F-FDG PET/CT revealed intense focal FDG avidity in the prostate. On further workup, he had an elevated serum IgG4 level, and a clinical diagnosis of immunoglobulin G4–related disease was kept. A follow-up FDG PET/CT after glucocorticoid therapy revealed resolution of FDG avidity in the prostate with fall in serum IgG4 levels, hence confirming a diagnosis of atypical immunoglobulin G4–related disease involving isolated prostate gland.
From the Departments of *Nuclear Medicine and PET/CT
†Gastroenterology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Received for publication January 14, 2019; revision accepted May 18, 2019.
Conflicts of interest and sources of funding: none declared.
Correspondence to: Bhagwant Rai Mittal, MD, DNB, Department of Nuclear Medicine and PET, A Block, Postgraduate Institute of Medical Education and Research, Sector 12, Chandigarh 160012, India. E-mail: firstname.lastname@example.org.
Online date: July 8, 2019