Imaging findings of immunoglobin G4-related hypophysitis: A case report

Abstract

BACKGROUND Immunoglobin G4 (IgG4)-related hypophysitis (IgG4-RH) is a rare form of IgG4-related disease (IgG4-RD), which often manifests as a single organ disease and is easily misdiagnosed as a pituitary tumor clinically and by imaging. There are few reports of imaging findings of IgG4-RH. Therefore, we describe a case of IgG4-RH, which mimicked a pituitary macroadenoma, that was detected by computed tomography (CT) and magnetic resonance imaging (MRI), and review the previous literature in order to further the understanding of IgG4-RH. CASE SUMMARY A 47-year-old man presented with a history of blurred vision for more than 2 mo, without other symptoms. A preoperative unenhanced CT scan revealed a slightly hyperdense mass in the sellar region measuring 2.5 cm × 2.3 cm × 1.8 cm, with a CT value of 45 HU. T1-weighted imaging (T1WI) and T2-weighted imaging showed iso-hypointensity, and gadolinium contrast-enhanced T1WI showed obvious homogeneous enhancement. The MRI revealed involvement of the pituitary gland and stalk. Preoperative laboratory tests revealed abnormal pituitary hormone levels, including an increased prolactin level, and decreased levels of insulin-like growth factor, dehydroepiandrosterone, and testosterone. The lesion was surgically resected. Postoperative histopathological examination of a tissue sample and an elevated serum IgG4 level confirmed the diagnosis of IgG4-RH. The patient was treated with cortisone acetate postoperatively and made a good recovery without developing any neurological deficit. CONCLUSION An elevated serum IgG4 concentration is the main clue for diagnosis of IgG4-RD. Imaging combined with laboratory testing is useful for preoperative diagnosis of IgG4-RH.

Hypophysitis: Defining Histopathologic Variants and a Review of Emerging Clinical Causative Entities

“…Computed tomography scan can sometimes feature adjacent bony changes. In IgG4-related disease, isohypointensity on T1- and T2-weighted imaging can be present and correspond to the degree of fibrosis and increased cellular infiltration [ 43 ]. However, a gadolinium-enhanced MRI is necessary for sellar and parasellar visualization [ 8 ].…”

Glucocorticoid impact therapy for recurrent IgG4-related disease with diabetes insipidus as the main manifestation: A case report and literature review

“…We used "hypophysitis," "IgG4-related hypophysitis," "diabetes insipidus" as keywords and searched on PubMed database. The review literature has been available for 115 cases of IgG4-RH before 2021, [1] so the search period was from January 1, 2021 to December 1, 2022, and 15 case reports were detected, [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] including 12 with complete clinical information and a total of 24 patients [2][3][4][5][6][7][9][10][11][12][13][14] (Table 1).…”