Diagnosis Of IgG4-related Hypophysitis Research Articles

Pituitary Abscess as Manifestation of IgG4-Related Hypophysitis: A Case Report

IgG4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory condition with heterogeneous organ-specific manifestations. IgG4-related hypophysitis results from pituitary involvement and represents a rare neuro-ophthalmic complication of IgG4-RD, but the presentation as pituitary abscess is exceptional. We report the case of a 38-year-old otherwise healthy woman with a 3-year history of relapsing pituitary sterile abscess repeatedly treated with neurosurgery and antimicrobials. Histological re-examination of pituitary biopsy specimens revealed a dense inflammatory infiltrate rich in IgG4-positive plasma cells. Serum IgG4 levels were normal and circulating plasmablasts were increased. A diagnosis of IgG4-related hypophysitis was made and the patient treated with high-dose steroid pulse therapy with subsequent reduction of the pituitary lesion and resolution of symptoms. This case highlights how the diagnostic intuition on the basis of histopathology has changed management with prompt dramatic response to steroid therapy.

Sellar germinoma mimicking IgG4-related hypophysitis: a case report

BackgroundThe differential diagnosis of IgG4-related hypophysitis and other inflammatory diseases or tumors involving sellar region is challenging even after sellar biopsy. Sellar germinoma is usually infiltrated by lymphocytes or plasma cells, and may be confused with hypophysitis.Case presentationA 36-year-old man with diabetes insipidus, elevated serum IgG4 level (336 mg/dl), and sellar mass was suspected to have IgG4-related hypophysitis, and no other lesion of IgG4-related disease was detected. After treated by prednisone and mycophenolate mofetil, the serum IgG4 decreased to 214 mg/dl. However, after withdrawal of the drugs, the IgG4 level increased to 308 mg/dl. Endocrine assessments revealed panhypopituitarism, and the sellar mass enlarged. Transsphenoidal sellar exploration and biopsy was conducted. Pathological examination showed that the lesion was germinoma with lymphocytes and plasma cells infiltration, and IgG4-staining was positive (70/HPF, IgG4/IgG ratio = 10%). The patient was then treated by cisplatin and etoposide. After four cycles of chemotherapy, the serum IgG4 was 201 mg/dl, and the sellar mass was invisible.ConclusionSellar germinoma can mimic the clinical characteristics of IgG4-related hypophysitis. Poor response to glucocorticoids can be used as an exclusion criterion in the clinical diagnosis of IgG4-related hypophysitis.

Hypophyseal Involvement in Immunoglobulin G4-Related Disease: A Retrospective Study from a Single Tertiary Center.

This study aims to outline the clinical features and outcomes of IgG4-related hypophysitis (IgG4-RH) patients in a tertiary medical center. We reviewed clinical manifestations and imaging and pituitary function tests at baseline, as well as during follow-up. Ten patients were included. The mean age at diagnosis of IgG4-RH was 48.4 (16.0–64.0) years. An average of 3 (0–9) extrapituitary organs were involved. Five patients had panhypopituitarism, three had only posterior hypopituitarism, one had only anterior hypopituitarism, and one had a normal pituitary function. One patient in our study had pituitary mass biopsy, lacking IgG4-positive cells despite lymphocyte infiltration forming an inflammatory pseudotumor. Five patients with a clinical course of IgG4-RH less than nine months and a whole course of IgG4-RD less than two years were managed with glucocorticoids, while three patients with a longer history were administered glucocorticoids plus immunosuppressive agents. One patient went through surgical excision, and one patient was lost to follow-up. All patients showed a prompt response clinically, but only three patients had normalized serum IgG4 levels. Two patients who took medications for less than six months relapsed. Conclusions. IgG4-RD is a broad disease, and all physicians involved have to be aware of the possibility of pituitary dysfunction. Younger patients should be expected. The histopathological feature of pituitary gland biopsy could be atypical. For patients with a longer history, the combination of GC and immunosuppressive agents is favorable. Early and adequate courses of treatment are crucial for the management of IgG4-RH. With GC and/or immunosuppressant treatment, however, pituitary function or diabetes insipidus did not improve considerably.

Rituximab was used to treat recurrent IgG4-related hypophysitis with ophthalmopathy as the initial presentation

Rationale:Immunoglobulin G4 (IgG4)-related hypophysitis is a type of IgG4-related disease (IgG4-RD), which is characterized by plasma cells infiltration in the pituitary causing functional changes and (or) space-occupying effect in the pituitary. IgG4-related hypophysitis is sensitive to hormone therapy in most patients, but recurrence is very likely.Patient concerns:Here, we report a 57-year-old male patient with bilateral eye redness as the initial presentation. He later presented with pituitary hypofunction that involved multiple organs, including eyes, lacrimal gland, pituitary, lung, gall bladder, and intestine. There was an elevation of C-reactive protein and blood sedimentation, but the IgG and IgG4 levels of the serum and the cerebrospinal fluid did not increase obviously following irregular glucocorticoid therapy. Magnetic resonance imaging revealed enlarged pituitary and obviously thickened pituitary stalk. IgG4-related hypophysitis was confirmed by biopsy of the pituitary.Diagnoses:The patient was diagnosis of IgG4-related hypophysitis with ophthalmopathy by pathological and molecular tests.Interventions:The patient responded to methylprednisolone pulse therapy but relapsed during the maintenance therapy using small-dose hormones combined with azathioprine. Methylprednisolone pulse therapy was given for 3 days followed by rituximab injection for 4 weeks.Outcomes:After use methylprednisolone pulse therapy with rituximab the patient achieved complete remission.Lessons:Rituximab achieved good effect for recurrent IgG4-related hypophysitis after glucocorticoid therapy combined with immunosuppressant in this case. Moreover, comparative analysis was carried out with other reported cases of IgG4-related hypophysitis in terms of clinical features, treatment, and follow-up.

Anti-pituitary antibodies against corticotrophs in IgG4-related hypophysitis.

IgG4-related disease is a systemic inflammatory disease characterized by infiltration of IgG4-positive plasma cells into multiple organs, including the pituitary gland. Autoimmunity is thought to be involved in the pathogenesis of IgG4-related disease. The diagnosis of IgG4-related hypophysitis (IgG4-RH) is difficult because its clinical features, such as pituitary swelling and hypopituitarism, are similar to those of other pituitary diseases, including lymphocytic hypophysitis and sellar/suprasellar tumors. The presence and significance of anti-pituitary antibodies (APA) in IgG4-RH is unclear. In this case-control study, we used single indirect immunofluorescence on human pituitary substrates to assess the prevalence of serum APA in 17 patients with IgG4-RH, 8 control patients with other pituitary diseases (lymphocytic infundibulo-neurohypophysitis, 3; craniopharyngioma, 2; germinoma, 3), and 9 healthy subjects. We further analyzed the endocrine cells targeted by the antibodies using double indirect immunofluorescence. APA were found in 5 of 17 patients with IgG4-RH (29%), and in none of the pituitary controls or healthy subjects. The endocrine cells targeted by the antibodies in the 5 IgG4-RH cases were exclusively corticotrophs. Antibodies were of the IgG1 subclass, rather than IgG4, in all 5 cases, suggesting that IgG4 is not directly involved in the pathogenesis. Finally, antibodies recognized pro-opiomelanocortin in 2 of the cases. Our study suggests that autoimmunity is involved in the pathogenesis of IgG4-RH and that corticotrophs are the main antigenic target, highlighting a possible new diagnostic marker for this condition.

Unusual IgG4-related hypophysitis: one case report and analysis of clinicopathological characteristics

Background Immunoglobulin G4 (IgG4)-related disease is a recently characterized autoimmune disease entity marked by elevated serum IgG4 levels and tissue infiltration by IgG4-positive plasma cells in multiple involved organs. Hypophysitis is a rare inflammatory disorder and IgG4-related sclerosing disease involving the ituitary alone is especially rare. Imaging studies may reveal a mass lesion in the sellar area or a thickening of pituitary stalk, mimicking a pituitary tumor. Due to its rarity and non-specific appearance in radiological examination, it is a diagnostic challenge for clinicians and histopathologists to differentiate solitary IgG4-related hypophysitis from other pituitary lesions. The aim of this study is to summarize the clinicopathological features of unusual IgG4-related hypophysitis and discuss the differential diagnosis of histologically similar inflammatory lesions in pituitary. Methods The clinical manifestation of a patient with solitary IgG4-related hypophysitis was presented retrospectively. Resected mass was routinely paraffin-embedded and stained with Hematoxylin and Eosin. Dako EnVision immunohistochemical staining system was used to detect the tumor antigen expressions, including vimentin (Vim), S-100 protein (S-100), pan cytokeratin (PCK), epithelial membrane antigen (EMA), CD3, CD20, CD68, CD1a, κ-light chain, λ-light chain and progestrone receptor (PR). Results A 47-year-old male patient presented with 1-year history of mild limb weakness and hyposexuality. Laboratory examination revealed hypopituitarism with low levels of serum testosterone, cortisol, luteinizing hormone (LH) and follicle stimulating hormone (FSH), although his serum IgG4 level was high. MRI of the pituitary gland revealed a mass lesion in the sellar area with T 1 WI mild hyperintense and homogeneous enhancement after gadolinium administration. The patient underwent a transsphenoidal mass resection of the pituitary gland. Histological examination showed bland appearing spindle cell proliferation in the sclerotic background with marked infiltration of lymphocytes, plasma cells, as well as multiple foci of meningothelial-like nodules at the periphery of tissues. Immunohistochemical staining showed that the lymphocytes were positive for CD3 and CD20. Plasma cells were distinct and the number of κ and λ-light chains was the same. There were more than 30 IgG4-positive plasma cells per high power field (HPF), which accounted for greater than 40% of the IgG-positive plasma cells. The meningothelial-like nodules were positive for Vim, EMA and PR, but negative for CD68, S-100 and CD1a. A final histological diagnosis of IgG4-related hypophysitis with meningothelial reaction was made. The patient took prednisolone orally at 35 mg/d for 2 weeks, and the symptoms of limb weakness and hyposexuality showed improvement. The mass lesion of pituitary gland demonstrated a reduction in size. The prednisolone therapy was continued at a dose of 30 mg/d to prevent recurrence of IgG4-related disease. Conclusions IgG4-related hypophysitis is a rare disease of central nervous system with good response to corticosteroid treatment. Due to the relative paucity of reported cases and similarities in histological findings, it may be difficult to differentiate IgG4-related disease from other pituitary lesions with prominent inflammatory cell infiltration and stromal fibrosis. Thorough inspection under the microscopy and more importantly elevated serum IgG4 level are necessary for correct diagnosis. doi: 10.3969/j.issn.1672-6731.2014.10.012