RESUMEN
BACKGROUND: Immunoglobulin G4 (Ig G4)-related disease is rare; however, it is a fibroinflammatory disease that has been studied a lot so far. Although the expression pattern varies depending on the organ affected, it usually manifests as organ hypertrophy and organ dysfunction. CASE PRESENTATION: A 46-year-old man was referred to our otorhinolaryngology department for left submandibular swelling and tenderness that occurred 2 weeks ago. He was treated with antibiotics (augmentin 625mg, per oral) for 2 weeks, but his symptoms did not improve, and his white blood cell (WBC) count was 10,500 /µL (normal 3,800-10,000 /µL). CONCLUSION: A mass-like lesion of the submandibular space has been concluded and the laboratory findings have been satisfactory (IgG4 level); IgG4-related disease, which is rare, but recently often reported, can be included in the differential diagnosis.