IgG4-related disease as multiple head and neck swellings: supported by histopathology and immunohistochemistry

A 66-year-old North-East Indian male presented with bilateral eyelid swelling, ptosis, and bilateral submandibular gland enlargement. Dry skin on both arms was another peculiar complaint. Contrast enhanced CT scans revealed homogenously enhancing, diffusely enlarged lacrimal glands and blood investigations showed raised serum IgG4 levels. Histopathology from lacrimal gland biopsy showed lymphoplasmacytic infiltrates in storiform pattern. Immunohistochemistry showed 35% plasma cells positive for IgG4. A diagnosis of IgG4-related disease was made, due to supportive histopathology, immunohistochemistry, and serum IgG4 levels. The patient showed excellent response to systemic immunomodulators. Abbreviations: IgG4-RD = IgG4-related disease, CECT = Contrast-enhanced computed tomography, ACE = Angiotensin converting enzyme, IHC = Immunohistochemistry, HPF = high power field, IgG4-ROD = IgG4-related ophthalmic disease, ACR/ EULAR = American College of Rheumatology/ European League Against Rheumatism.