IgG4-related hypophysitis

IgG4-related hypophysitis is a rare cause of inflammation of the pituitary gland and an uncommon manifestation of the systemic IgG4-related disease (IgG4-RD).


Although IgG4-RD tends to present in middle-aged and elderly men, the gender ratio is more balanced in patients with IgG4-related hypophysitis and other head and neck manifestastions of IgG4-RD .

Clinical presentation

Clinical features depend on the part of the pituitary gland involved :


IgG4-related hypophysitis is characterized by chronic inflammation of the pituitary gland with histology revealing lymphoplasmacytic infiltrate rich in IgG4-positive plasma cells . This classic histological finding differentiates it from the histological appearances of other etiologies of hypophysitis, those being:

  • lymphocytic hypophysitis: lacks plasma cells and presents in a young female demographic
  • granulomatous hypophysitis: has multinucleated giant cells that form true granulomas, is secondary to diseases such as neurosarcoidosis, and also tends to present in a young female demographic
  • xanthomatous hypophysitis: has foamy histiocytes (xanthoma cells) and macrophages
  • necrotizing hypophysitis: extremely rare and has necrosis with only scattered pituitary tissue remaining

Radiographic features

Although this is a very rare entity, common radiographic findings that have been reported include non-specific enlargement of the pituitary gland with or without infundibulum enlargement that is visible on both CT and MRI . Post-contrast T1-weighted MR images may further reveal enhancement .

Other associated head and neck manifestations of IgG4-RD, such as IgG4-related hypertrophic pachymeningitis, may also be seen .

Treatment and prognosis

Based on case series-level evidence, good response is seen to corticosteroids such as prednisolone or hydrocortisone . Treatment of endocrine hormone deficiencies (e.g. giving desmopressin for diabetes insipidus) is also prudent .

Differential diagnosis

The differential diagnosis is primarily that of other pituitary region masses. Considerations include: