Executive summary of the consensus document on hypophysitis of the Neuroendocrinology Area of Knowledge of the Spanish Society of Endocrinology and Nutrition

The term hypophysitis is used to designate a heterogeneous group of pituitary conditions characterized by the presence of inflammatory infiltration of the adenohypophysis, neurohypophysis, or both. Although hypophysitis are rare disorders, the most common in clinical practice is lymphocytic hypophysitis, a primary hypophysitis characterized by lymphocytic infiltration, which predominantly affects women. Other forms of primary hypophysitis are associated with different autoimmune diseases. Hypophysitis can also be secondary to other disorders such as sellar and parasellar diseases, systemic diseases, paraneoplastic syndromes, infections, and drugs, including immune checkpoint inhibitors. The diagnostic evaluation should always include pituitary function tests and other analytical tests based on the suspected diagnosis. Pituitary magnetic resonance imaging is the investigation of choice for the morphological assessment of hypophysitis. Glucocorticoids are the mainstay of treatment for most symptomatic hypophysitis.

Pregnancy-related hypophysitis revisited

OBJECTIVE

The aim of the study is to assess the distinguishing features of pregnancy-related hypophysitis (PR-Hy) compared to non-pregnancy autoimmune hypophysitis and to evaluate the changing therapeutic approaches and outcomes in PR-Hy over time.

DESIGN

Retrospective analysis of all published cases with PR-Hy and 6 own cases.

METHODS

A PubMed search was performed and abstracts screened for publications with information on cases with PR-Hy from which full-text review was performed. Clinical features, diagnostic findings, and outcome in relation to treatment modalities in PR-Hy were assessed.

RESULTS

One hundred and forty-eight cases with PR-Hy were identified. PR-Hy was significantly delimited from non-PR-Hy by the frequent occurrence of the chiasmal syndrome (50% vs 13%, P < .0001), higher rate of intrasellar origin (94% vs 74%, P = .0005), lower rate of pituitary stalk involvement (39% vs 86%, P < .0001), and low rate of diabetes insipidus (12% vs 54%, P < .0001). The role of surgery in PR-Hy decreased over time while noninvasive treatment modalities increased. The recurrence rate after high-dose glucocorticoid therapy (33%) was high and exceeded that of surgery (2%) and conservative management (2%). In contrast to initial reports on PR-Hy, recent literature regarding outcome of mother's and child's health was positive. The frequency of spontaneous preterm delivery was not increased. Recurrent PR-Hy in a subsequent pregnancy was reported in only two females.

CONCLUSION

PR-Hy has distinct features that delineate the disorder from non-PR-Hy. With increasing experience in diagnosis, availability of adequate replacement therapy, and improved treatment modalities, PR-Hy has lost its threat and the outcome is encouraging.

[Primary hypophysitis: diagnosis and treatment multicenter study]

INTRODUCTION

Primary hypophysitis (PH) is a rare disease that represents a challenge among differential diagnosis and management. Our aim was to describe clinical characteristics, diagnostic criteria and different treatment outcomes in patients with PH. Multicentric, retrospective study. Clinical presentation, endocrine function, magnetic resonance imaging findings, visual field defects at diagnosis and treatment outcomes were recorded.

METHODS

Twenty-eight patients (23 women), with PH were included. Median age: 37.

RESULTS

The most frequent symptoms: headache: 68%, polyuria-polydipsia: 50% and visual disturbances: 48%. At diagnosis, anterior pituitary deficiency was present in 71%, being hypogonadotrophic hypogonadism the most frequent manifestation. The radiological findings: symmetric lesion: 78.5%, homogeneous enhancement: 78.5% and pituitary stalk thickening: 70%. Association with pregnancy or puerperium was found in 4/23 women (17%). Fourteen patients did not receive any treatment ("wait and see" group), 8 underwent surgery for mass reduction or resection and 6 were treated with immunosuppression therapy. Among 15 patients with histopathological diagnosis, 9 were lymphocytic hypophysitis, 5 IgG4 related hypophysitis and 1 xanthomatous hypophysitis. Thirteen were diagnosed by established clinical criteria. Mass reduction was observed in 43% of "wait and see group" patients, 62.5% of operated patients and 50% with immunosuppression therapy. Compressive symptoms showed improvement in the 3 groups, with modest effect on anterior pituitary function, diabetes insipidus did not resolve in any patients.

DISCUSSION

In patients without severe compressive symptoms, we adopted a "wait and see" approach. In patients with uncertain diagnosis of PH or severe compressive symptoms, transsphenoidal surgery was the best option.

Inhibition of IRAK1 Is an Effective Therapy for Autoimmune Hypophysitis in Mice

Autoimmune hypophysitis (AH) is an autoimmune disease of the pituitary for which the pathogenesis is incompletely known. AH is often treated with corticosteroids; however, steroids may lead to considerable side effects. Using a mouse model of AH (experimental autoimmune hypophysitis, EAH), we show that interleukin-1 receptor-associated kinase 1 (IRAK1) is upregulated in the pituitaries of mice that developed EAH. We identified rosoxacin as a specific inhibitor for IRAK1 and found it could treat EAH. Rosoxacin treatment at an early stage (day 0-13) slightly reduced disease severity, whereas treatment at a later stage (day 14-27) significantly suppressed EAH. Further investigation indicated rosoxacin reduced production of autoantigen-specific antibodies. Rosoxacin downregulated production of cytokines and chemokines that may dampen T cell differentiation or recruitment to the pituitary. Finally, rosoxacin downregulated class II major histocompatibility complex expression on antigen-presenting cells that may lead to impaired activation of autoantigen-specific T cells. These data suggest that IRAK1 may play a pathogenic role in AH and that rosoxacin may be an effective drug for AH and other inflammatory diseases involving IRAK1 dysregulation.

Diagnosis and treatment of autoimmune and IgG4-related hypophysitis: clinical guidelines of the Japan Endocrine Society

Hypophysitis, which is often accompanied by pituitary dysfunction, is classified into several subtypes based on the cause, histology, and the location of inflammation in the pituitary gland. A definitive diagnosis requires pituitary biopsy, which is invasive, and the process is limited to specialized clinical settings. In this opinion paper, we review the literature associated with hypophysitis, and provide the guidelines of the Japan Endocrine Society for the diagnosis and treatment of autoimmune and IgG4-related hypophysitis.

Hypophysitis: An update on the novel forms, diagnosis and management of disorders of pituitary inflammation

Hypophysitis is a heterogeneous condition that leads to inflammation of the sella and/or suprasellar region, potentially resulting in hormonal deficiencies and/or mass effects. A preponderance of hypophysitis subtypes have an underlying autoimmune aetiology. The overall incidence and prevalence of hypophysitis has dramatically increased over the past decade, mainly due to increased awareness of the condition in the medical community, improvements in imaging techniques, and a rise in the occurrence of certain forms of hypophysitis such as IgG4 hypophysitis (IgG4Hy) and immune checkpoint inhibitor induced hypophysitis (ICIHy). The clinical presentation varies from an asymptomatic condition to a fatal disease often as a result of electrolyte abnormalities due to glucocorticoid deficiency in the context of adrenal crisis from central adrenal insufficiency. Milder forms of hypophysitis are treated with replacement of deficient hormones while more acute presentations with mass effects require glucocorticoid therapy, immunosuppressive therapy or surgery. Timely diagnosis and interventions are keys to prevention of the lethal complications of this disease. In this review, we provide an update on the recent advances in the field of pituitary autoimmunity, with an emphasis on autoimmune hypophysitis and novel forms of hypophysitis such as anti-PIT1 hypophysitis, IgG4Hy and ICIHy.

New causes of hypophysitis

Hypophysitis is a rare entity characterized by inflammation of the pituitary gland and its stalk that can cause hypopituitarism and/or mass effect. Etiology can be categorized as primary or secondary to systemic disease, but may also be classified according to anatomical and hispathological criteria. Newly recognized causes of hypophysits have been described, mainly secondary to immunomodulatory medications and IgG4-related disease. Diagnosis is based on clinical, laboratory and imaging data, whereas pituitary biopsy, though rarely indicated, may provide a definitive histological diagnosis. For the clinician, obtaining a broad clinical and drug history, and performing a thorough physical examination is essential. Management of hypophysitis includes hormone replacement therapy if hypopituitarism is present and control of the consequences of the inflammatory pituitary mass (e.g. compression of the optic chiasm) using high-dose glucocorticoids, whereas pituitary surgery is reserved for those unresponsive to medical therapy and/or have progressive disease. However, there remains an unmet need for controlled studies to inform clinical practice.

The management of hypophysitis

Hypophysitis is generally accepted as an autoimmune disease which is characterized by inflammation and cellular infiltration of the pituitary gland. It can be either primary or secondary. In this review, treatment of primary hypophysitis of various histological subtypes are discussed. Management of primary hypophysitis is usually symptomatic aiming to reduce the size of the pituitary mass and/or replace deficient pituitary hormones. Observation with replacement for deficient pituitary hormones can be applied in some group of patients. Keeping the complications of surgery in mind, surgical intervention should be limited to cases with severe and/or deteriorating compressive signs or cases with inconclusive findings of hypophysitis in whom treatment would be based on histopathological examination. The most commonly used drugs in the treatment of hypophysitis are glucocorticoids. They are able to reduce the size of the mass lesion with their anti-inflammatory effects and sometimes pituitary functions may also recover. However, there is no consensus about the optimal duration and dose of glucocorticoid use. When glucocorticoids and/or surgery fail, azathioprine, methotrexate, cyclosporin A and novel immunotherapies can be tried as third or forth line treatment. Radiotherapy and radiosurgery have been seldom used for treatment of hypophysitis in order to reduce the mass effect.

Lymphocytic infundibulo-neurohypophysitis: a clinical overview

Lymphocytic infundibulo-neurohypophysitis is an uncommon inflammatory disorder postulated to be autoimmune in origin. Because of the location of inflammation, it selectively affects the posterior lobe of the pituitary (neurohypophysis) and pituitary stalk (infundibulum). The most common presentation is central diabetes insipidus. Although the definitive diagnosis is established histologically by a pituitary biopsy, radiological imaging can be valuable in diagnosing this condition. In this paper, we provide an overview of the pathophysiology, investigations, management, and outcomes of lymphocytic infundibulo-neurohypophysitis.

Hypophysitis: a single-center case series

PURPOSE

The authors review their treatment experience and summarize clinical outcomes for patients with hypophysitis over the past 15 years.

METHODS

A retrospective analysis was conducted on patients with lymphocytic, granulomatous or IgG4-related hypophysitis treated from 1997 to 2014 at a single academic center. Patients' medical records were reviewed and binary logistic regression analysis was used to assess whether various clinical parameters were associated with improved outcomes including endocrine function, radiographic appearance and disease recurrence.

RESULTS

Twenty-one patients (13 women and 8 men) were identified with a median diagnosis age of 37.4 years. All but two patients (90%) were diagnosed histopathologically and the remaining two were diagnosed clinically with lymphocytic hypophysitis. 16 patients (76%) had lymphocytic hypophysitis, 3 (14%) had granulomatous hypophysitis, 1 (5%) had IgG4-related hypophysitis and 1 (5%) had mixed lymphocytic-granulomatous. Patients presented with various symptoms of expanding sellar mass with most common signs including headache (57%), polyuria/polydipsia (52%), vision changes (52%) and amenorrhea or decreased libido (48%). Pre-treatment endocrine evaluation revealed that 12 (57%) patients had complete anterior hypopituitarism, 11 patients (52%) had diabetes insipidus, ten patients (48%) had mild hyperprolactinemia and three patients (14%) had isolated endocrine axis deficiencies with partial gland function. We observed a broad diversity in pre-treatment imaging with common findings including uniform contrast enhancement (62%), thickened infundibulum (57%) and loss of hypophysis bright spot on T1 imaging (43%). Patients were treated with steroids and hormone supplementation as needed. 16 patients (76%) had recorded post-treatment MRI scans which revealed that half had radiographic improvement and half had stable or worsened post-treatment imaging. Only female gender was found to significantly predict improved odds of post-steroid radiographic improvement. For post-treatment endocrine evaluation, six patients (29%) did not have an evaluation on record, four patients (19%) had some improvement in at least one axis, seven patients (33%) had stable but non-worsened endocrine function and four patients (19%) had worsened endocrine function post-steroids.

CONCLUSIONS

Hypophysitis is an increasingly recognized diagnosis that can present with a broad array of radiographic and clinical features. Surgical biopsy can be helpful to make definitive diagnosis and may guide treatment decision-making.

Treatment of Primary Hypophysitis in Germany

CONTEXT

The best treatment of primary hypophysitis (PrHy) is a matter of debate.

OBJECTIVE

Our main objective was to analyze the treatment practice for PrHy in Germany and to compare the outcome of the main treatment options.

DESIGN

The Pituitary Working Group of the German Society of Endocrinology conducted a nationwide retrospective cross-sectional cohort study.

PATIENTS

Seventy-six patients with PrHy were eligible for the study.

MAIN OUTCOME MEASURES

Clinical and endocrinological outcomes, side effects and complications of therapy, initial response, and recurrence rates were assessed. Outcome depending on the treatment modality was evaluated.

RESULTS

For mere observation, regression of space-occupying lesions was observed in 46%, unchanged size in 27%, and progression reported in 27%. Pituitary function improved in 27% of patients during observation. Deterioration of pituitary function was only found in patients with progressive lesions. The initial response to glucocorticoid pulse therapy was most favorable, with early failure in only 3%. However, the overall failure and recurrence rate was 41%. Recurrence rate was not related to duration of steroid administration. Side effects of steroids occurred in 63%. The surgical approach was transsphenoidal in 94%. The histological subtype was lymphocytic hypophysitis in 70% and granulomatous hypophysitis in 30%. Progression or recurrence was observed in 25% after surgical treatment.

CONCLUSION

Glucocorticoid pulse therapy is associated with a high recurrence rate. Evidence suggests that surgery is not able to prevent recurrence. Considering the favorable results of observation, conservative management is recommended in PrHy unless symptoms are severe or progressive.