A 69-year-old with well-controlled HIV was evaluated for persistent cough, in the context of years of fatigue and influenza A infection 6 months prior. Chest CT and PET scans were notable for adenopathy concerning for a lymphoproliferative disorder. Radiologic studies also showed diffuse FDG uptake in the prostate, consistent with prostatitis. Axillary lymph node biopsy showed follicular and paracortical hyperplasia, and few germinal centers showed perifollicular non-necrotizing granulomas. Immunohistochemical staining demonstrated a predominance of IgG4 positive plasma cells. Serum protein electrophoresis (SPEP) and immunosubtraction showed a board-domed peak pattern suggestive of possible monoclonality. Serum IgG4 levels were elevated, and the patient was diagnosed with IgG4-related disease (IgG4-RD). This case highlights morphologic and SPEP patterns that can aid in supporting a diagnosis of IgG4-RD.
Keywords: Granulomas; IgG4 related disease; Lymphadenopathy; SPEP.
© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.