The spectrum and significance of primary hypophysitis

Pituitary Complications of Checkpoint Inhibitor Use

Immune checkpoint inhibitors have revolutionized cancer therapy but are associated with a risk of endocrine immune-related adverse events, including pituitary complications. Autoimmune hypophysitis, traditionally a rare diagnosis, has become a more frequently encountered clinical entity with the emergence of antitumor immunotherapy. This mini-review aims to consolidate current knowledge, encompassing the epidemiology, pathophysiology, clinical presentation, diagnosis, and management of pituitary complications of immune checkpoint inhibitor use.

Inflammatory and Infectious Disorders in Endocrine Pathology

A variety of inflammatory conditions may directly involve the endocrine glands, leading to endocrine dysfunction that can cause severe consequences on patients' health, if left untreated. Inflammation of the endocrine system may be caused by either infectious agents or other mechanisms, including autoimmune and other immune-mediated processes. Not infrequently, inflammatory and infectious diseases may appear as tumor-like lesions of endocrine organs and simulate neoplastic processes. These diseases may be clinically under-recognized and not infrequently the diagnosis is suggested on pathological samples. Thus, the pathologist should be aware of the basic principles of their pathogenesis, as well as of their morphological features, clinicopathological correlates, and differential diagnosis. Interestingly, several systemic inflammatory conditions show a peculiar tropism to the endocrine system as a whole. In turn, organ-specific inflammatory disorders are observed in endocrine glands. This review will focus on the morphological aspects and clinicopathological features of infectious diseases, autoimmune disorders, drug-induced inflammatory reactions, IgG4-related disease, and other inflammatory disorders involving the endocrine system. A mixed entity-based and organ-based approach will be used, with the aim to provide the practicing pathologist with a comprehensive and practical guide to the diagnosis of infectious and inflammatory disorders of the endocrine system.

Systematic Review of Treatment Options and Therapeutic Responses for Lesions of the Sella and Orbit: Evidence-Based Recommendations

OBJECTIVE

Inflammatory pathologies of the sella and orbit are rare but require prompt diagnosis to initiate effective treatment. Because uniform recommendations for treatment are currently lacking, we performed an evidence-based review to identify recommendations.

METHODS

We performed a literature search of the PubMed, Embase, and Web of Science databases to identify papers evaluating treatment of inflammatory pathologies of the sella and orbit. We used PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to define recommendations, specifically examining aggregated sample sizes, disease-specific patient follow-up, and clinical trials focused on inflammatory diseases of the sella and orbit.

RESULTS

A total of 169 studies were included and organized by disease pathology. Treatments for various pathologies were recorded. Treatment options included surgery, radiation, steroids, targeted treatments, immunomodulators, intravenous immune globulin, and plasmapheresis. Steroids were the most often employed treatment, second-line management options and timing varied. Pathological diagnosis was highly associated with treatment used. Most evidence were level 3 without available control groups, except for 13 trials in neuromyelitis optica with level 1 or 2 evidence.

CONCLUSIONS

This is the first evidence-based review to provide recommendations on specific treatments for pathologies of the orbit and sella. The reported data may be useful to help guide randomized clinical trials and provide resource for clinical management decisions based on the available evidence.

[Pituitary insufficiency: basics in diagnosis and therapy]

Pituitary insufficiency is a partial or complete failure of secretion of one or more hormones from the pituitary gland. The pituitary gland is located in the hypophysial fossa of the sella turcica of the os sphenoidale and produces ACTH, LH, FSH, GH, TSH, and prolactin. Pituitary insufficiency can be caused by acute damage, such as secondary to traumatic brain injury. It can also be a result of chronic alterations, such as increasing tumor expansion.Pituitary insufficiency often presents with nonspecific symptoms (e.g. fatigue, listlessness, decreased performance, sleep disturbances, weight change) that leads to a challenging and sometimes delayed diagnosis. The symptoms correspond to the failure of the corresponding endorgans. Occasionally, symptoms such as a loss of libido, secondary amenorrhea or nausea in stressful situations are diagnostically indicative.Further clarification includes a clinical examination with endocrinological testing of the pituitary function. Alteration of pituitary hormone secretion can also occur physiologically as in pregnancy, depression or obesity. Substitution therapy of the failed corticotropic, thyrotropic and gonadotropic axis is corresponding to the therapy of a primary endorgan insufficiency. Adequate diagnosis and treatment of pituitary insufficiency is important, as this may prevent life-threatening crises such as an adrenal crisis.

A case of pituitary gland abscess associated with granulomatous hypophysitis

BACKGROUND

Granulomatous hypophysitis is a rare disease that presents with chronic inflammation of the pituitary gland. In this study, we reported a case of granulomatous hypophysitis associated with a pituitary abscess.

CASE PRESENTATION

A 39-year-old woman presented with a 2-year history of infertility. For the past six months, she has suffered from amenorrhea, decreased libido, headaches, and vertigo. She was referred to our hospital with a suspected diagnosis of nonfunctioning pituitary adenoma based on her presentation and brain MRI findings. She underwent trans-sphenoidal surgery (TSS). Direct observation during surgery revealed drainage of malodor pus and pituitary gland abscess. The histopathological evaluation also showed granulomatous hypophysitis and neutrophilic microabscess formation. The patient was initially treated with high doses of ceftriaxone (2 g twice daily) and metronidazole (500 mg (mg) four times per day). Also, the patient received cortisol replacement therapy after the operation. After obtaining the antibiogram and culture results, the treatment regimen was continued for 4 weeks postoperatively, followed by amoxicillin-clavulanate (500/125 mg three times daily) for a total duration of 12 weeks.

CONCLUSION

The patient recovered uneventfully and the postoperative MRI was normal without any remnant lesions.

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.

Xanthomatous Hypophysitis Secondary to a Ruptured Rathke's Cleft Cyst: A Case Report

Hypophysitis (HP) is a rare disease which develops secondary to chronic or acute inflammation of the pituitary gland and may cause symptoms related to pituitary dysfunction and mass compression. Lymphocytic HP is the most common subtype of primary HP, while xanthomatous HP (XHP) is considered the rarest form, with 35 reported cases, to date. A 35-year-old woman was initially admitted to a Gynecology clinic with a 2-year history of amenorrhea and headache. She was started on cabergoline 0.5 mg twice a week for macroprolactinoma. Due to persistent amenorrhea with low gonadotropins, she was referred to our Endocrinology clinic. Her pituitary function profile revealed panhypopituitarism and a 13×11×12 mm sized sellar mass with diffuse enhancement which sustained toward the infundibulum and dura was observed on the gadolinium-enhanced pituitary MRI. The patient underwent an endoscopic endonasal transsphenoidal approach for tumor resection and thick yellowish fluid draining from the lesion was observed. The histopathological diagnosis was reported as a rupture of an Rathke’s cleft cyst and an XHP. The surgery did not improve the symptoms/pituitary functions, however, headache recovered immediately after the first dose of high dose methylprednisolone treatment. The inflammatory process in a xanthomatous lesion may actually be a secondary response to mucous fluid content release from a ruptured cyst, thus recommended to classify XHP as secondary hypophysitis. Since the differentiation of XHP from other pituitary tumors may be challenging preoperatively, surgery is the major diagnostic tool and also, the most recommended therapeutic option.

Full recovery from chronic headache and hypopituitarism caused by lymphocytic hypophysitis: A case report

BACKGROUND

Lymphocytic hypophysitis (LYH) is an important condition to consider in the differential diagnosis of patients with a pituitary mass. The main clinical manifestations of LYH include headache, symptoms related to sellar compression, hypopituitarism, diabetes insipidus and hyperprolactinemia. Headache, which is a frequent complaint of patients with LYH, is thought to be related to the occupying effect of the pituitary mass and is rapidly resolved with a good outcome after timely and adequate glucocorticoid treatment or surgery.

CASE SUMMARY

Here, we report a patient with LYH whose initial symptom was headache and whose pituitary function assessment showed the presence of secondary hypoadrenalism, central hypothyroidism and hypogonadotropic hypogonadism. Pituitary magnetic resonance imaging showed symmetrical enlargement of the pituitary gland with suprasellar extension in a dumbbell shape with significant homogeneous enhancement after gadolinium enhancement. The size of the gland was approximately 17.7 mm × 14.3 mm × 13.8 mm. The pituitary stalk was thickened without deviation, and there was an elevation of the optimal crossing. The lesion grew bilaterally toward the cavernous sinuses, and the parasternal dural caudal sign was visible. The patient presented with repeatedly worsening and prolonged headaches three times even though the hypopituitarism had fully resolved after glucocorticoid treatment during this course.

CONCLUSION

This rare headache regression suggests that patients with chronic headaches should also be alerted to the possibility of LYH.

Hypothalamic-Pituitary Autoimmunity in Patients Treated with Anti-PD-1 and Anti-PD-L1 Antibodies

Simple Summary

The aim of this study is to search for APA and AHA and related pituitary dysfunction in patients treated with immunotherapy. APA and AHA could represent markers for early detection of patients at risk of developing pituitary deficiencies related to immune checkpoint inhibitors and undergoing closer follow-up. Furthermore, this study aims to evaluate the correlation between the presence of AHA and APA and the clinical response to checkpoint inhibitor therapy. However, further prospective studies will be needed to confirm our results.

Abstract

Background: Autoimmune hypophysitis is a frequent immune-related adverse event (irAE) in cancer patients treated with immunecheckpoint inhibitors. Studies seeking anti-pituitary (APA) and anti-hypothalamus (AHA) antibodies in patients treated with anti-PD-1 and anti-PD-L1 are scarce. The aim of this study is to search for APA and AHA and related pituitary dysfunction in patients treated with these agents. Methods:Cross-sectional and preliminary longitudinal studies were conducted at the Medical Oncology Unit and Endocrinology and Metabolic Diseases Unit of the University of Campania “Luigi Vanvitelli”. Fifty-four cancer patients on treatments with anti-PD-1 or anti-PD-L1 (Group 1) and 50 healthy controls were enrolled for a cross-sectional study; 13 cancer patients (Group 2) were enrolled for our preliminary longitudinal study. APA/AHA titers and changes in biochemical and hormonal profile were evaluated in Group 1; in Group 2, they were evaluated before and after nine weeks from the start of immunotherapy. Results: Patients of Group 1 showed a higher prevalence of APA and AHA than controls: 21 of them had APA, 16 had AHA, and 11 had both autoantibodies. In total, 7 of 13 patients in Group 2 became APA-positive and 3 became AHA-positive after nine weeks of immunotherapy, showing an increase in prolactin and a decrease in ACTH and IGF-1 levels compared with basal values. Conclusions:Anti-pituitary and anti-hypothalamus antibodies seem to play a pivotal role in hypothalamic–pituitary autoimmunity and secondary endocrine-related alterations evoked by anti-PD-1 and PD-L1 antibodies.

Xanthomatous Hypophysitis: A Case Report and Comprehensive Literature Review

PURPOSE

Xanthomatous hypophysitis (XHP) is an extremely rare form of primary hypophysitis for which there is a lack of clinical experience. A comprehensive understanding of its clinical characteristics, diagnosis and treatment is needed.

METHODS

Here, we report a case study and conduct a systematic review of XHP. Thirty-six cases were included, and their clinical manifestations, endocrine assessment, imaging features, treatment and follow-up data were collected and analyzed.

RESULTS

The mean age at diagnosis was 39.1 years, and females were predominant (75.0%). The most common symptom was headache (68.6%), and 66.7% of female patients presented menstrual disorders. The most common pituitary dysfunction was growth hormone (GH) deficiency. More than half of patients exhibited central diabetes insipidus (CDI). The majority of patients had an imaging presentation of a cystic lesion with peripheral enhancement. Pituitary stalk thickening was observed in half of the patients. Total lesion resection was achieved in 57.1% of cases. The recurrence rate after partial resection and biopsy was significantly higher than that after total lesion resection (57.1% vs. 0.0%, P = 0.0147). The most common pituitary hormone abnormalities to resolve after surgery were hyperprolactinemia (100.0%) and GH deficiency (91.7%). The typical pathological feature was inflammatory infiltration of foamy histiocytes, which showed positivity for CD68.

CONCLUSION

Diagnosis of XHP is difficult when relying on clinical symptoms and imaging features. Therefore, surgical histopathology is necessary. Based on the available evidence, total lesion resection is recommended for treatment. However, the long-term prognosis for this rare disease remains unclear.

Recurring Primary Xanthomatous Hypophysitis Behaving Like Pituitary Adenoma: Additional Case and Literature Review

BACKGROUND

Xanthomatous hypophysitis (XH) is the rarest histologic type of primary hypophysitis. It is nonlymphocytic and characterized by an infiltration of the pituitary gland by lipid-laden histiocytes and macrophages. The clinical and radiologic features overlap heavily with pituitary adenomas and are prone to misdiagnosis. We describe a rare case of XH recurrence at 1 year, treated surgically. Moreover, we provide an updated review of the literature to further elucidate useful management and detection strategies.

CASE DESCRIPTION

A 45-year-old woman presented with a history of menstrual irregularity for 9 months, amenorrhea, galactorrhea, and headache for 2 months duration. Preoperative endocrinologic studies showed increased prolactin levels. Magnetic resonance imaging of the sella showed a cystic lesion with suprasellar extension suggestive of a pituitary adenoma. The patient underwent transsphenoidal resection, showing a thick yellowish colloidal material. Histopathology showed necrotic tissue with no definitive diagnosis and no identified microorganisms. At 2 months after surgery, prolactin levels and menstrual cycle normalized. At 1 year after surgery, her menstrual cycle again became irregular. Repeat magnetic resonance imaging showed a recurrent mass and a second transsphenoidal resection was undertaken. Repeat histopathology was consistent with XH. The patient is 9 years postoperative and is doing well without evidence of recurrence.

CONCLUSIONS

XH presents similarly to nonfunctional adenomas and diagnosis remains difficult without surgical pathology, requiring meticulous immunohistochemistry to prevent misdiagnosis. Thus, XH should be considered as a rare cause in the differential of disease of the sellar region. Management can parallel that of pituitary neoplasm, with a focus on radiosurgery, re-resection, and high-dose steroids.

Two cases of immunoglobulin G4 (IgG4)-related hypophysitis diagnosed without pituitary biopsy

BACKGROUND

Immunoglobulin G4-related hypophysitis (IgG4-RH) is a rare disease, diagnosis of which typically depends on histopathology following an invasive pituitary biopsy, possibly leading to permanent hypopituitarism. Herein, we report two cases of IgG4-RH with favorable responses to glucocorticoids. One of them was multiple organs involved and treated with glucocorticoids and methotrexate.

METHODS

We retrospectively review clinical features, radiological images, and treatment of two cases with IgG4-RH. In addition, literature on IgG4-RH was comprehensively reviewed and a new therapeutic strategy for IgG4-RH was provided.

RESULTS

A 45-year-old man presented with diabetes insipidus for 6 months. Pituitary magnetic resonance imaging (MRI) indicated thickening of pituitary stalk. His serum IgG4 was 13,500 mg/l and hormonal evaluation revealed isolated growth hormone deficiency. Pituitary biopsy was denied by the patient due to fears of permanent pituitary damage. Treatment with prednisone and methotrexate (MTX) for 1 week led to improvement in sellar images and reduction in IgG4 level. His IGF1 (insulin-like growth factor-1) recovered after a 4-month treatment. The second case is a 43-year-old woman presenting with diabetes insipidus and amenorrhea for 20 months. Her pituitary MRI was similar to the patient above. Her serum IgG4 level was 5980 mg/l and hormonal measurement confirmed isolated hypogonadotropic hypogonadism. After 2 weeks of prednisone, the sellar images improved. After 3 months of treatment, her pituitary MRI was normal, IgG4 level had decreased to near normal range, and menstruation resumed. Literature review found additional patients with IgG4-RH, who were treated successfully without invasive pituitary biopsy in a manner similar to our cases. Therefore, we discuss the necessity of invasive pituitary biopsy for IgG4-RH.

CONCLUSION

For suspected IgG4-RH with pituitary hormone deficiency, biopsy-induced hypopituitarism may be avoided by using diagnostic glucocorticoid treatment. Impaired pituitary hormone secretion may be recovered in response to steroid therapy. Improved pituitary MRI after 1-2 weeks of glucocorticoid treatment may provide diagnostic evidence of IgG4-RH.

Infundibuloneurohypophysitis associated with autoimmune thrombocytopenia and chiasmal syndrome: a case report

Lymphocytic hypophysitis is an uncommon autoimmune disease. It may involve the adenohypophysis, neurohypophysis and pituitary stalk. It is most often encountered in pregnant women. Its diagnosis and management pose a significant challenge, as its clinical manifestation and appearance in imaging studies are difficult to distinguish from more common lesion of the sellar region (e.g., pituitary adenomas). We present the case of a 42-year-old man who presented with a chiasmatic syndrome, diabetes insipidus and hypopituitarism. Brain MRI documented a sellar lesion with suprasellar extension and optic chiasm dislocation. He underwent an endoscopic endonasal transsphenoidal resection of the mass. Histopathological examination revealed a lymphocytic hypophysitis. Visual symptoms improved dramatically postoperatively with permanent diabetes insipidus and panhypopituitarism. We discuss the indication for surgical resection in patients with inflammatory lesions extending to the suprasellar region associated with visual impairment.

Primary hypophysitis: Experience of a Single Tertiary Center

PURPOSE

The authors review the clinical outcomes of patients with primary hypophysitis (PH).

METHODS

Patients with PH who were followed up between 2007 and 2018 at our clinic were evaluated. Clinical, endocrinologic, pathologic, radiologic findings and treatment modalities were assessed.

RESULTS

Seventeen patients with PH were assessed. The median follow-up was 24 (range, 6-84) months. Histologic confirmation was available in 8 patients (6 lymphocytic hypophysitis, 1 lymphocytic-granulomatous hypophysitis, 1 xanthomatous hypophysitis). None of the cases were diagnosed after pregnancy. Two patients had an autoimmune disease. The most commonly seen symptom was headache. The most common anterior pituitary deficiencies were hypocortisolemia and hypothyroidism. The radiologic findings of the patients at the time of diagnosis revealed various results including space-occupying lesion (41.2%), loss of posterior hypophysis bright spot (47.1%), pituitary stalk thickening (41.2%), uniform contrast enhancement (17.6%), partially empty sella (11.8%), optic chiasm compression (11.8%). The most frequent initial treatment modality was observation. Ten patients who were followed up conservatively had no endocrinologic deterioration; additional treatment was not needed in 8 of these 10 patients. The second most frequent initial treatment modality was pituitary surgery. Five patients received steroid treatment. We found serious adverse effects during steroid treatment in 3 of 5 (60%) patients; unilateral avascular necrosis of the femoral head (n=2), diabetes mellitus(n=1).

CONCLUSION

Correctly diagnosing PH and giving appropriate treatment is challenging. It is unclear whether active treatment with steroids improves clinical outcomes. The serious adverse effects of steroids are also taken into account. Observation, surgery and/or radiotherapy can be appropriate treatment modalities for selected patients.

Clinical and hormonal characteristics of patients with different types of hypophysitis: a single-center experience

OBJECTIVE

The inflammation of the pituitary gland is known as hypophysitis. It is a rare disease accounting for approximately 0.24%-0.88% of all pituitary diseases. The natural course of hypophysitis is variable. Main forms are histologically classified as lymphocytic, granulomatous, IgG4 related and xanthomatous. We aim to present our patients with hypophysitis and compare clinical, laboratory and radiological features.

SUBJECTS AND METHODS

We retrospectively reviewed our database of 1.293 patients diagnosed with pituitary diseases between 2010 and 2017. Twelve patients with hypophysitis were identified. Demographical data, clinical features, endocrinological dysfunction, imaging findings, treatment courses and follow-up periods were evaluated.

RESULTS

The frequency of hypophysitis was found 0.93% in all cases of the pituitary disease. Twelve patients (nine females and three males), ages between 17-61 years, were evaluated. The characteristic features of our patients tended to be predominantly female and young. Diagnosis of hypophysitis was made after pituitary biopsy in four patients, and in eight patients after pituitary operation due to adenoma. Headache (67%) and visual problems (33%) were the most frequent nonendocrine symptoms. Anterior pituitary hormone deficiencies (63.7%) and/or diabetes insipidus (17%) were seen among patients. According to histopathological forms, four had lymphocytic, seven had granulomatous and one had xanthogranulomatous types. Contrast enhancement heterogeneous and thickened pituitary stalk were the most common radiological alterations.

CONCLUSION

Hypophysitis should be considered in the differential diagnosis of sellar masses. It can mimic pituitary adenomas in radiological and endocrinological aspects. The different patterns of pituitary hormone deficiencies may be seen in the course of the disease.

Primary hypophysitis and other autoimmune disorders of the sellar and suprasellar regions

The pituitary gland and the hypothalamus can be affected by autoimmune-mediated structural and functional disruption. These autoimmune-mediated diseases occur more commonly in females and are often found during pregnancy or in the post-partum period. Autoimmune diseases can either affect parts of the pituitary or hypothalamus, or can involve both sellar and suprasellar structures. Most of these cases comprise primary hypophysitis (PRH). Over the years, there has been a tremendous increase in the number of reported PRH cases and related disorders, including hypophysitis induced by immune checkpoint inhibitors. With this increasing data, more light is being shed on the spectrum of clinical presentations, biochemical and imaging abnormalities of these disorders. Regardless, these disorders are still relatively rare. The clinical presentation can vary vastly, based on the type of pituitary cell or the area of the suprasellar region affected. The severity can range from clinically silent disease to progressive and rapid deterioration and death, likely due to unrecognized central adrenal insufficiency. Although biopsy remains a gold standard for diagnosing these disorders, the current standard of practice is biochemical assessment for hormonal deficiencies and imaging studies. In several instances, these disorders spontaneously resolve, but medical or surgical intervention might be necessary to treat symptomatic disease. Due to the subtlety and a vast spectrum of clinical manifestations which could often be asymptomatic, and the rarity of the occurrence of these diseases in clinical practice, the diagnosis can be easily missed which could potentially lead to substantial morbidity or mortality. Therefore, it is crucial to have a strong clinical suspicion and pursue timely biochemical and imaging studies to initiate prompt treatment. In this article, we review the various autoimmune conditions that affect the sellar and suprasellar structures, their diagnostic approach and management of these disorders.

Idiopathic granulomatous hypophysitis: A report of an uncommon disorder

Hypophysitis of the pituitary gland is a rare inflammatory disorder and broadly classified as primary and secondary hypophysitis. Primary hypophysitis is mainly of lymphocytic, granulomatous, and xanthomatous types. Among the various primary hypophysitis, granulomatous hypophysitis is rare type with an incidence of 1 in 10 million. The various forms of hypophysitis are misdiagnosed as pituitary adenoma in 40% cases. Idiopathic granulomatous hypophysitis is even rarer inflammatory disorder accounting for <1% of cases involving panhypopituitarism with headache and visual disturbances. We report idiopathic granulomatous hypophysitis in a 28-year-old female presenting with blurring of vision and headache.

Cystic Lymphocytic Hypophysitis Mimicking Pituitary Apoplexy: Daunting Challenge

BACKGROUND

Inflammatory lesions of the pituitary gland including hypophysitis are poorly understood, and it is difficult to make a correct diagnosis on the basis of only clinical and radiologic findings.

CASE DESCRIPTION

An otherwise healthy 68-year-old man presented with sudden onset of headache, visual impairment, and pituitary insufficiency. Magnetic resonance imaging revealed a pituitary mass with cystic component showing changing intensity on follow-up images. Also, changing density of the lesion was demonstrated on computed tomography over a short period of time. These findings suggested a hemorrhagic lesion, and a preoperative diagnosis of pituitary apoplexy associated with a preexisting pituitary adenoma was made on the basis of clinical and radiologic findings. In the endoscopic endonasal approach for tumor resection, there was neither hematoma nor adenoma. Histopathologic diagnosis was lymphocytic hypophysitis.

CONCLUSIONS

To the best of our knowledge, this is the first case report of hypophysitis with radiologic signal changes over a short period. Vigilant attention regarding the clinical diagnosis of such rare entity is paramount.

Immunohistochemical Biomarkers in Pituitary Pathology

Pituitary pathology is one area of endocrine pathology that is highly dependent on immunohistochemistry. There is a wide range of disorders that occur in and around the sella turcica, and the distinction of tumor-like lesions from neoplasms requires careful evaluation. The diagnosis, prognosis, and predictive features of neoplasms in the sellar region are all dependent on the application and interpretation of biomarkers of cell differentiation, hormonal activity, subcellular morphology, and proliferation. As in hematopathology, the number of biomarkers has increased dramatically and continues to increase. Fortunately, some of the biomarkers provide information that was initially dependent on electron microscopy; therefore, the need for this additional technology has been reduced to only rare unusual tumors. In this review, we provide a simple approach to understanding the importance of the various biomarkers that are used to ensure the correct diagnosis and provide the treating clinicians with tools to guide appropriate patient management and surveillance.

Hypophysitis following Treatment with Ustekinumab: Radiological and Pathological Findings

CONTEXT

Ustekinumab is a human IgG1 monoclonal antibody that targets interleukin (IL)-12 and IL-23, which may be useful in the treatment of autoimmune conditions such as psoriasis, psoriatic arthritis, and Crohn's disease. Hypophysitis is an immune-derived inflammatory condition of the pituitary gland that may lead to pituitary dysfunction. With the increasing use of immunotherapy, it is possible that this and other new immune-related adverse events (IRAEs) arise, although the mechanisms involved are still incompletely defined.

CASE DESCRIPTION

A 35-year-old male, with a previous history of severe plaque-psoriasis who had started treatment with ustekinumab 4 months before, complained of progressive and persistent headache. Brain magnetic resonance imaging (MRI) was unremarkable. One year later, a new MRI was performed due to headache persistence, which revealed a homogenous and diffuse pituitary enlargement, with suprasellar extension and optic chiasm involvement, blurring of the pituitary stalk, absence of clear differentiation between the anterior and posterior lobes, and no signs of hemorrhage or adenomas. Endocrine evaluation was consistent with panhypopituitarism. Work-up of infiltrative and infectious diseases was negative. Follow-up MRI revealed an increase in the pituitary enlargement and transsphenoidal surgery was performed. Pathological findings revealed an intense fibrosis and a chronic inflammatory infiltrate, but no evidence of adenoma, granuloma, or acid fast bacilli. Immunohistochemical staining showed a combined T-cell (CD3+, CD4+) and B-cell (CD19+, CD20+) phenotype.

CONCLUSION

We suggest a novel IRAE of ustekinumab, with full radiological and immunopathological iconography, which may be mediated by the complex interaction between different immunological processes.

Immunoglobulin G4 (IgG4)-Related Hypophysitis

We report two different cases of IgG4-related hypophysitis. In the first case, a pituitary lesion was accompanied by lymphocytic meningitis possibly mimicking tuberculous meningitis. The second case was unassociated with involvement of other organs. No histologic differences were noted between the two cases indicating that the morphologic features of the hypophysial lesion do not depend on the presence of other lesions. The pathogenesis of IgG4 hypophysitis is not known, and further study is necessary to explore the cause, progression, and influencing factors of this disease.

Granulomatous hypophysitis: rare disease with challenging diagnosis

Granulomatous hypophysitis is rare pathology that mimics pituitary adenoma. Diagnosis is only confirmed by histopathology examination. Trans‐sphenoidal surgery is considered diagnostic when descent tissue specimen is obtained and therapeutic by decompressing optic pathway and the sella. Pathological findings always reveal granulomatous areas, multinucleated giant cells, plasma cells, and lymphocytes.

DIAGNOSIS OF ENDOCRINE DISEASE: Expanding the cause of hypopituitarism

Hypopituitarism is defined as one or more pituitary hormone deficits due to a lesion in the hypothalamic-pituitary region. By far, the most common cause of hypopituitarism associated with a sellar mass is a pituitary adenoma. A high index of suspicion is required for diagnosing hypopituitarism in several other conditions such as other massess in the sellar and parasellar region, brain damage caused by radiation and by traumatic brain injury, vascular lesions, infiltrative/immunological/inflammatory diseases (lymphocytic hypophysitis, sarcoidosis and hemochromatosis), infectious diseases and genetic disorders. Hypopituitarism may be permanent and progressive with sequential pattern of hormone deficiencies (radiation-induced hypopituitarism) or transient after traumatic brain injury with possible recovery occurring years from the initial event. In recent years, there is increased reporting of less common and less reported causes of hypopituitarism with its delayed diagnosis. The aim of this review is to summarize the published data and to allow earlier identification of populations at risk of hypopituitarism as optimal hormonal replacement may significantly improve their quality of life and life expectancy.

Novel aspects in histopathology of the pituitary gland

The sellar and parasellar region is a complex anatomical area in which several diseases may develop. The pituitary gland may be affected by a wide range of conditions having similar clinical characteristics. Diagnosis of these lesions requires a multidisciplinary approach including, in addition to clinical, laboratory, imaging, and surgical findings, histological diagnosis of pituitary adenomas to guide therapeutic management. As the result of development in recent years of new immunohistochemical techniques, histopathological classification has become more complex and wide, and not only continues to be the gold standard in diagnosis, but also has prognostic implications. The aim of this review is to provide a clear and simple update of the main concepts of histological diagnosis of the most common pituitary conditions, especially for professionals in direct contact with such diseases.

Review of xanthomatous lesions of the sella

Xanthomatous lesions of the sellar region have traditionally been divided into two separate categories, xanthomatous hypophysitis (XH) and xanthogranuloma (XG) of the sellar region. The seminal article on XH, a condition typified by foamy histiocytes and lymphoplasmacytic infiltrates in the pituitary gland/sellar region, but usually little or no hemosiderin pigment, detailed three patients. However, most reports since that time have been single cases, making understanding of the entity difficult. In contrast, the seminal report on XG, characterized by sellar region cholesterol clefts, lymphoplasmacytic infiltrates, marked hemosiderin deposits, fibrosis, multinucleated giant cells around cholesterol clefts, eosinophilic granular necrotic debris, and accumulation of macrophages, included 37 patients, allowing more insights into etiology. Few examples could be linked to adamantinomatous craniopharyngioma, and although ciliated epithelium similar to that of Rathke cleft cyst (RCC) was identified up to 35% of the 37 cases, it could not be proven that XG was related to hemorrhage into RCC. Case reports since that time, however, occasionally linked XG to RCC when an etiology could be identified at all, and a few recognized that a spectrum exists in xanthomatous lesions of the sella. They review literature, adding 23 cases from our own experience, to confirm that overlap occurs between XH and XG, and that the majority-but not all-can be linked to RCC leakage/rupture/hemorrhage. It was suggested that progressive accumulation of hemosiderin pigment in the lesion, possibly caused by the multiple episodes of bleeding, could account for the transition of at least some cases of XH to XG.

Lymphocytic hypophysitis: modern day management with limited role for surgery

PURPOSE

We set out to describe the modern day management of Lymphocytic hypophysitis (LH) with respect to its diagnosis, treatment and long-term endocrine and visual outcomes. We deliberately included patients with a clinical diagnosis of LH and compared them with those with a histological diagnosis following surgery.

METHODS

A multi-centre observational study was performed. Twenty-two patients were included and studied over a mean follow-up period of 8.6 years (range 4-26 years).

RESULTS

Patients presented with headache (N = 15; 68 %), visual field disturbances (N = 7; 32 %) or a combination of these symptoms (N = 5; 23 %). The time lag between onset of symptoms and diagnosis was <1 month, 1-6 months or >6 months in approximately a third of the patients each, respectively. In two-thirds of the patients (N = 14) LH was diagnosed based on their clinical, biochemical and radiological findings. The surgical cohort (N = 8) was statistically more likely to have presented with larger lesions, with suprasellar extension and greater visual field defects. During follow-up there was improvement in headaches and visual symptoms, but the rate of hypopituitarism as reflected by the need for on-going pituitary hormone replacement persisted. At the 1, 5 and 10 year follow-up there was no significant difference between the medically and surgically managed cohorts in terms of ongoing symptomatology or need for pituitary hormone replacement.

CONCLUSIONS

In the modern era, most patients with LH are diagnosed by non-surgical means and managed medically. There remains a significant time lag between the onset of symptoms and the eventual diagnosis of LH. Despite the considerable morbidity attached to LH, overall prognosis is good.

In Situ Activation of Pituitary-Infiltrating T Lymphocytes in Autoimmune Hypophysitis

Autoimmune hypophysitis (AH) is a chronic inflammatory disease characterized by infiltration of T and B lymphocytes in the pituitary gland. The mechanisms through which infiltrating lymphocytes cause disease remain unknown. Using a mouse model of AH we assessed whether T lymphocytes undergo activation in the pituitary gland. Infiltrating T cells co-localized with dendritic cells in the pituitary and produced increased levels of interferon-γ and interleukin-17 upon stimulation in vitro. Assessing proliferation of CD3- and B220-postive lymphocytes by double immunohistochemistry (PCNA-staining) and flow cytometry (BrdU incorporation) revealed that a discrete proportion of infiltrating T cells and B cells underwent proliferation within the pituitary parenchyma. This proliferation persisted into the late disease stage (day 56 post-immunization), indicating the presence of a continuous generation of autoreactive T and B cells within the pituitary gland. T cell proliferation in the pituitary was confirmed in patients affected by autoimmune hypophysitis. In conclusion, we show that pituitary-infiltrating lymphocytes proliferate in situ during AH, providing a previously unknown pathogenic mechanism and new avenues for treatment.

Xanthomatous Hypophysitis Is Associated with Ruptured Rathke's Cleft Cyst

Xanthomatous hypophysitis is a rare inflammatory disease of the pituitary gland that can mimic a neoplastic lesion clinically and radiologically. Its pathogenesis remains largely unknown, although recent evidence suggests that pituitary inflammation may occur as a secondary reaction to mucous content released from a ruptured cyst. In a series of 1221 pituitary specimens, we identified seven cases of xanthomatous hypophysitis. Six patients had complete radiological and biochemical workup preoperatively: a cystic-appearing pituitary mass was identified in all six patients (100%) with a mean size of 2.0 cm (range 1.4-2.5 cm) on imaging, and pituitary endocrine dysfunction was noted in five patients (83.3%). In all cases, the pituitary mass was resected through an endoscopic transsphenoidal approach. Pathological examination revealed the presence of foamy macrophages admixed with variable amounts of giant cells and chronic inflammatory cells, confirming the diagnosis of xanthomatous hypophysitis. Additionally, all cases presented with concurrent findings of ruptured Rathke's cleft cyst, with the exception of one patient who had previous surgery for a Rathke's cleft cyst, followed by recurrence and diagnosis of xanthomatous hypophysitis. While accurate distinction of hypophysitis from a pituitary neoplasm can be problematic in the preoperative setting, the identification of a cystic lesion in the sella turcica should raise the possibility of such an entity in the clinical and radiological differential diagnosis. The current series provides further evidence that xanthomatous hypophysitis predominantly occurs as a secondary reaction to a ruptured Rathke's cleft cyst; thus, it is best classified as a secondary (reactive) hypophysitis.

Novel aspects in histopathology of the pituitary gland

The sellar and parasellar region is a complex anatomical area in which several diseases may develop. The pituitary gland may be affected by a wide range of conditions having similar clinical characteristics. Diagnosis of these lesions requires a multidisciplinary approach including, in addition to clinical, laboratory, imaging, and surgical findings, histological diagnosis of pituitary adenomas to guide therapeutic management. As the result of development in recent years of new immunohistochemical techniques, histopathological classification has become more complex and wide, and not only continues to be the gold standard in diagnosis, but also has prognostic implications. The aim of this review is to provide a clear and simple update of the main concepts of histological diagnosis of the most common pituitary conditions, especially for professionals in direct contact with such diseases.

Histological features of pituitary adenomas and sellar region masses

PURPOSE OF REVIEW

Most pituitary region masses are pituitary adenomas; however, when other sellar region masses are encountered by clinicians or pathologists, the differential diagnosis can be broad. This review will focus on updates for pituitary adenomas, as well as briefly discuss some of these other entities: Rathke cleft cyst, hypophysitis, craniopharyngioma, pituicytoma, and spindle cell oncocytoma.

RECENT FINDINGS

The use of new immunohistochemical (IHC) tools for assessing transcription factors, pituitary transcription factor-1, steroidogenic factor-1, and the not-yet-widely available Tpit IHC have provided insights into origin particularly of clinically silent and even hormone-negative pituitary adenomas. IHC for keratins coupled with use of E-cadherin IHC can serve to easily identify sparsely granulated growth hormone adenomas that behave more aggressively and may not respond well to some therapies. Thyroid transcription factor-1 IHC has shown common embryological lineage of pituicytoma, spindle cell oncocytoma, and granular cell tumor of neurohypophysis.

SUMMARY

IHC supplements classification of pituitary adenoma subtypes for clinicians and can confirm diagnosis of nonpituitary adenoma sellar region masses.

Revisitation of autoimmune hypophysitis: knowledge and uncertainties on pathophysiological and clinical aspects

PURPOSE

This publication reviews the accepted knowledges and the findings still discussed on several features of autoimmune hypophysitis, including the most recently described forms, such as IgG4 and cancer immunotherapy- related hypophysitis.

METHODS

The most characteristic findings and the pending controversies were derived from a literature review and previous personal experiences. A single paragraph focused on some atypical examples of the disease presenting under confounding pretences.

RESULTS

Headache, visual field alterations and impaired pituitary secretion are the most frequent clinical findings of the disease. Pituitary biopsy, still considered the gold diagnostic standard, does not always receive consent from the patients. The role of magnetic resonance imaging is limited, as this disease may generate images similar to those of other diseases. The role of antipituitary and antihypothalamus antibodies is still discussed owing to methodological difficulties and also because the findings on the true pituitary antigen(s) are still debated. However, the low sensitivity and specificity of immunofluorescence, one of the more widely employed methods to detect these antibodies, may be improved, considering a predetermined cut-off titre and a particular kind of immunostaining.

CONCLUSION

Autoimmune hypophysitis is a multifaceted disease, which may certainly be diagnosed by pituitary biopsy. However, the possible different clinical, laboratory and imaging features must be considered by the physician to avoid a misdiagnosis when examining a possibly affected patient. Therapeutic choice has to be made taking into account the clinical conditions and the degree of hypothalamic-pituitary involvement, but also considering that spontaneous remissions can occur.

Granulomatous hypophysitis: a case of severe headache

Idiopathic granulomatous hypophysitis (GH) is an uncommon inflammatory disease of the pituitary with impairment of pituitary gland function due to infiltration by lymphocytes, plasma cells and macrophages. We report the case of a 39-year-old woman who presented with worsening of headaches for 1 month and blurring of vision over 5 days. An MRI revealed a homogeneous supra-sellar mass evoking a pituitary tumour with bulky pituitary stalk extending into the left and right cavernous sinuses. Hormonal investigations showed anterior pituitary hormone deficiencies; meanwhile histopathological examination revealed an aspect of hypophysitis. Clinical and radiological remission occurred immediately postglucocorticoid therapy with the addition of a steroid-sparing agent later in view of recurrence of symptoms on glucocorticoid dose reduction. GH has important diagnostic and therapeutic implications, as clinical and radiological features ameliorate via medical treatment. With further understanding and recognition of the disease, we hope to highlight a case of GH, in which signs and symptoms improved after initiation of corticosteroids.

Postpartum Granulomatous Hypophysitis: A Case Study, Review of the Literature, and Discussion of Pathogenesis

Hypophysitis is a rare inflammatory condition of the pituitary gland that has three main histologic subtypes: lymphocytic hypophysitis (LH), granulomatous hypophysitis (GH), and xanthomatous hypophysitis (XH). Among these, LH is the most common and is strongly associated with the postpartum state, while XH is the least common. Many hypophysitis cases have been reported in the literature but only a few cases of postpartum GH have been discussed. Here, we describe a case of GH in a 24-year-old female presenting eleven days postpartum. We also review the current literature on postpartum GH and discuss the possible alterations in the immune environment during and after pregnancy that could explain this phenomenon. With more cases of GH being reported, the commonalities of female predominance, postpartum time of presentation, and occasional spontaneous resolution between LH and GH lend support to the theory that these two diseases likely represent spectrums of a single immunologic disorder.

Xanthomatous hypophysitis associated with autoimmune disease in an elderly patient: A rare case report

Background:

Xanthomatous hypophysitis (XH) is an extremely rare form of primary hypophysitis characterized by infiltration of the pituitary gland by mixed types of inflammatory cells, including foamy cells, plasma cells, and small mature lymphocytes. XH manifests as varying degrees of hypopituitarism. Although several previous reports have denied a possible contribution of autoimmune mechanism, the exact pathogenesis of XH remains unclear.

Case Description:

We describe the case of a 72-year-old woman with a history of rheumatoid arthritis and Sjögren's syndrome who presented with panhypopituitarism and diabetes insipidus. At the time of her visit, she also experienced relapsed rheumatoid arthritis and Sjögren's syndrome, manifesting as arthralgia. Magnetic resonance imaging (MRI) showed a multicystic mass in the sellar and suprasellar regions. In the course of steroid replacement therapy for hypocortisolism, the patient's arthralgia diminished, and MRI revealed shrinkage of the mass. XH was diagnosed histologically following a transsphenoidal endoscopic biopsy, and it was the oldest case of XH.

Conclusion:

To the best of our knowledge, this patient is the oldest of reported patients diagnosed with XH. Steroid therapy may be effective to XH temporarily. XH should be considered when diagnosing pituitary cystic lesions in elderly patients with autoimmune disease.

Diagnosis and management of tumor-like hypophysitis: A retrospective case series

Tumor-like hypophysitis is an uncommon sellar condition that presents as inflammatory lesions on the structures of the pituitary gland. The diagnosis and management of hypophysitis poses a significant challenge, as its clinical manifestation and appearance in imaging studies are difficult to distinguish from that of pituitary tumors. The present retrospective study summarizes two rare cases of primary granulomatous hypophysitis, two cases of lymphocytic hypophysitis, and three cases in which a pathological diagnosis was not determined due to the use of hormone replacement therapy only. The mean age of the patients studied was 45.71±22.16 years, and the patients comprised two males and five females. The clinical signs of hypophysitis included headache, fever, gradual decrease in visual acuity, nausea and vomiting. Enhanced magnetic resonance imaging revealed sellar and pituitary stalk lesions, with iso- or hypodense signals on T1-weighted images. Transsphenoidal surgery was performed in three cases. It was challenging to diagnose hypophysitis due to the lack of any significant specific clinical signs. A transsphenoidal biopsy with fast-frozen pathology is able to diagnose hypophysitis. Glucocorticoid therapy may be a potential treatment for hypophysitis, as complete removal of pituitary masses may disable pituitary function.

Xanthomatous hypophysitis

We present a 69-year-old woman who presented with chronic headaches and was found to have a pituitary mass on MRI, which was biopsied and said to be lymphocytic hypophysitis. The woman was placed on prednisone and followed with routine eye examinations. Two years later, the lesion gradually increased in size and the woman developed a decrease in peripheral vision in the right eye. An MRI showed abutment of the right optic nerve by the mass. A repeat endoscopic transsphenoidal biopsy/resection of the pituitary lesion was performed. Histopathological analysis of the specimen was consistent with diagnosis of xanthomatous hypophysitis (XH). XH is an inflammatory disorder of the pituitary gland characterized by an infiltration of lipid-laden histiocytes, also known as xanthoma cells. The mass was biopsied and a diagnosis of lymphocytic hypophysitis was made. The woman reported improved visual acuity and peripheral vision postoperatively. One year after the second resection, her visual symptoms worsened. Repeat MRI revealed expansion of the residual pituitary tissue. She was referred to the radiation oncology department for external beam radiation therapy and was placed on a maintenance dose of steroids. Since undergoing radiation therapy, her vision has improved slightly and her 3month MRI revealed stable lesion size. This woman illustrates a rare pituitary pathology presented with a literature review of published patients describing xanthomatous hypophysitis. A discussion of the clinical presentation, epidemiology, etiology, diagnosis, histology and treatment is provided.

A rare case of autoimmune hypophysitis presenting as temperature dysregulation

Autoimmune hypophysitis is a rare cause of pan-hypopituitarism. Hypothalamic involvement in autoimmune hypophysitis is rare and usually manifests as central diabetes insipidus due to antibodies against arginine vasopressin. Temperature dysregulation is occasionally seen with suprasellar tumours but has never been reported with hypophysitis. We report a case of a middle aged man who presented to us with the complaints of documented body temperature fluctuations since two months followed gradually by hoarseness of voice, sexual dysfunction and syncope. Examination was remarkable for postural hypotension, dry coarse skin and delayed ankle reflexes. Patient's hormone profile revealed pan-hypopituitarism and elevated titre of anti-TPO antibodies. Patient's work up for secondary causes of hypopituitarism was negative. MRI brain revealed typical findings of hypophysitis. Patient was suspected as a case of autoimmune hypophysitis and was immediately treated with prednisolone along with hormone replacement. Rapid response within 30 days was observed in the form of subsidence of temperature fluctuations, improvement in general well being, sexual function and repeat MRI done after one month which revealed a partial empty sella. Autoimmune hypophysitis as a potentially treatable cause of temperature dysregulation has been highlighted in this case.

Clinical characteristics, management, and outcome of 22 cases of primary hypophysitis

BACKGROUND

Primary hypophysitis causes varying degrees of endocrine dysfunction and mass effect. The natural course and best treatment have not been well established.

METHODS

Medical records of 22 patients who had been diagnosed with primary hypophysitis between January 2001 and March 2013 were retrospectively reviewed. Based on the anatomical location, we classified the cases as adenohypophysitis (AH), infundibuloneurohypophysitis (INH), and panhypophysitis (PH). Clinical presentation, endocrine function, pathologic findings, magnetic resonance imaging findings, and treatment courses were reviewed.

RESULTS

Among 22 patients with primary hypophysitis, 81.8% (18/22) had involvement of the posterior pituitary lobe. Two patients of the AH (2/3, 66.6%) and three patients of the PH (3/10, 30%) groups initially underwent surgical mass reduction. Five patients, including three of the PH (3/10, 33.3%) group and one from each of the AH (1/3, 33.3%) and INH (1/9, 11.1%) groups, initially received high-dose glucocorticoid treatment. Nearly all of the patients treated with surgery or high-dose steroid treatment (9/11, 82%) required continuous hormone replacement during the follow-up period. Twelve patients received no treatment for mass reduction due to the absence of acute symptoms and signs related to a compressive mass effect. Most of them (11/12, 92%) did not show disease progression, and three patients recovered partially from hormone deficiency.

CONCLUSION

Deficits of the posterior pituitary were the most common features in our cases of primary hypophysitis. Pituitary endocrine defects responded less favorably to glucocorticoid treatment and surgery. In the absence of symptoms related to mass effect and with the mild defect of endocrine function, it may not require treatment to reduce mass except hormone replacement.

Use of serum pituitary antibodies to improve the diagnosis of hypophysitis

Lymphocytic hypophysitis is characterized by an extensive infiltration of lymphocytic cells. Pituitary biopsy is the gold diagnostic standard for lymphocytic hypophysitis but the disease occurs with moderate or without pituitary enlargement. The role of antipituitary antibodies (APA) in autoimmune hypophysitis is still discussed due to various methodological difficulties. Indirect immunofluorescence, a widely employed method to detect APA at this time produces highly variable results due to the use of human or animal pituitary substrates. For many years the authors have conducted a re-evaluation of APA by immunofluorescence in patients with other autoimmune diseases and in patients with apparently idiopathic hypopituitarism, using pituitary from young baboons as substrate but considering a predetermined cut-off of the titer and immunofluorescence pattern. This procedure allowed us to find out those with autoimmune pituitary impairment and to foresee the kind of future hypopituitarism in those with pituitary function still normal. Moreover, in APA positive patients, the use of a second step of a double immunofluorescence method allowed identification of the pituitary cells targeted by APA, verifying the correspondence with the kind of hypopituitarism, also when present in subclinical stage. However, to carry out an international workshop comparing the detection of APA by immunofluorescence using different substrates could contribute to verify the best choice to improve the sensitivity and specificity of this method.

Idiopathic granulomatous hypophysitis: a systematic review of 82 cases in the literature

Idiopathic granulomatous hypophysitis (IGH) is a rare inflammatory disease of the pituitary. There is debate in the scientific literature as to whether IGH represents a continuum of disease with lymphocytic hypophysitis or has a distinct pathogenesis. Due to the rare nature of the disease, previous descriptions have been limited to single case reports or small series. In the present study, a systematic review of the literature was performed for cases of IGH. 82 cases met inclusion criteria. Data was gathered on IGH clinical aspects, in order to elucidate any associations useful in determining pathogenesis, appropriate clinical treatment, or prognosis. Univariate and multivariate analysis was performed on available data. Female sex was significantly associated with IGH (p < 0.0001). Fever (p = 0.002), nausea or vomiting at presentation (p = 0.031), and histological evidence of necrosis (p = 0.022) correlated with reduced time to presentation. Panhypopituitarism at presentation predicted need for long term hormone replacement (p = 0.014). Hyperprolactinaemia (p = 0.032), normal gonadal (p = 0.037) and thyroid axes (p = 0.001) were associated with reduced likelihood of long-term hormone replacement. Anorexia (p = 0.017), cold intolerance (p = 0.046), and fatigue (p = 0.0033) were associated with death from IGH. Patients who had excisional surgery alone trended towards increased rates of symptom resolution, compared with patients who received corticosteroids as an adjunct to excisional surgery (p = 0.11). This article details the first systematic review of IGH, and presents evidence for a female predilection of the disease. Implications for pathogenesis, and a suggested clinical approach are discussed. An online disease registry has been established to facilitate further IGH research.

Diagnosis and classification of autoimmune hypophysitis

Autoimmmune hypophysitis (AH) is the consequence of an immune-mediated inflammation of the pituitary gland. The initial pituitary enlargement, secondary to infiltration and oedema, can evolve to remission, for spontaneous or pharmacological resolution of the inflammation, or evolve to progressive diffuse destruction with gland atrophy for fibrotic replacement, thus leading to various degrees of pituitary dysfunction. The autoimmune process against the pituitary gland is made evident by the appearance of circulating autoantibodies (APA), mainly detected by indirect immunofluorescence on cryostatic sections of human or primate pituitary. Among the target autoantigens recognized by APA are alpha-enolase, gamma-enolase, the pituitary gland specific factors (PGSF) 1 and 2 and corticotroph-specific transcription factor (TPIT). However, the low diagnostic sensitivity and specificity of APA for AH strongly limit the clinical use of this marker. AH should be considered in the differential diagnosis of non-secreting space-occupying lesions of sella turcica, to avoid misdiagnosis that may lead to an aggressive surgery approach, since endocrine dysfunction and the compressive effect may be transient.

Autoimmune hypophysitis presenting with intracranial multi-organ involvement: three case reports and review of the literature

Background

Autoimmune hypophysitis very rarely spreads to nearby organs outside the pituitary tissue, for unknown reasons, with only 5 reported cases of hypophysitis spreading over the cavernous sinus.

Case presentation

Three patients presented with cases of non-infectious hypophysitis spreading outside the pituitary tissue over the cavernous sinus. All three cases were diagnosed with histological confirmation by transsphenoidal surgery, and the patients showed remarkable improvement with postoperative pulse dose steroid therapy, including disappearance of abnormal signal intensities in the bilateral hypothalami on magnetic resonance imaging, resolution of severe stenosis of the internal carotid artery, and normalization of swollen pituitary tissues. Two of 3 cases fulfilled the histological criteria of immunoglobulin G4-related disease, although none of the patients had high serum immunoglobulin G4 level.

Conclusion

The true implications of such unusual spreading of hypophysitis to nearby organs are not fully understood, but the mechanism of occurrence might vary according to the timing of inflammation in this unusual mode of spreading. Pulse dose steroid therapy achieved remarkably good outcomes even in the patient with progressive severe stenosis of the internal carotid artery and rapid visual deterioration.

Update on hypophysitis and TTF-1 expressing sellar region masses

This article reviews recent literature on sellar region masses that most closely mimic nonsecretory pituitary adenomas: hypophysitis, pituicytoma, spindle cell oncocytoma, and granular cell tumor of neurohypophysis. Even today, these four entities often cannot be confidently distinguished from each other clinically or by preoperative neuroimaging features. Thus, they often come to biopsy/surgical resection and require tissue confirmation of diagnosis. Causes of secondary and primary hypophysitis will be discussed, including two newly described types, IgG4 plasma cell hypophysitis and hypophysitis caused by anti-cytotoxic T-lymphocyte antigen 4 antibody therapy for cancer. For the neoplastic conditions, emphasis will be placed on literature that has emerged since these entities were first codified in the 2007 World Health Organization fascicle. The finding that immunohistochemical staining for thyroid transcription factor-1 is shared by pituicytoma, spindle cell oncocytoma, and granular cell tumor of neurohypophysis suggests common lineage and explains why histological overlap can be encountered. We incorporate our own experiences over the last 30 years from two referral institutions with specialty practices in pituitary region masses.

Steroid responsive xanthomatous hypophysitis associated with autoimmune thyroiditis: a case report

We report the case of a 36-year-old woman who presented with headache, fever, and amenorrhea. Laboratory analysis revealed hypopituitarism and autoimmune thyroiditis, while a cerebrospinal fluid study suggested concurrent aseptic meningitis. A magnetic resonance image (MRI) scan revealed a 1.0×0.9 cm cystic mass enlarging the sella turcica. Surgical resection via an endoscopic transsphenoidal route was performed. The histological finding of the excised tissue revealed foamy histiocytes with vacuolated cytoplasm, supporting the diagnosis of xanthomatous hypophysitis. Although a residual soft lesion was observed on the MRI image postoperatively, the patient's headache and fever improved. Ten months after surgery, the patient complained of visual impairment and headache, and the residual mass had enlarged into the suprasellar area. High dose (500 mg intravenous) methylprednisolone was administered for 3 days. During the methylprednisolone pulse therapy, the patient's visual acuity and headache improved. A follow-up MRI taken after methylprednisolone therapy showed a marked mass reduction. Our case supports an autoimmune pathophysiology for xanthomatous hypophysitis and suggests that high dose glucocorticoid therapy as a treatment option.

A case of idiopathic granulomatous hypophysitis

Granulomatous hypophysitis is a rare pituitary condition that commonly presents with enlargement of the pituitary gland. A 31-year-old woman was admitted to the hospital with a severe headache and bitemporal hemianopsia. Magnetic resonance imaging (MRI) showed an 18 × 10-mm sellar mass with suprasellar extension and compression of the optic chiasm. Interestingly, brain MRI had shown no abnormal finding 4 months previously. On hormonal examination, hypopituitarism with mild hyperprolactinemia was noted. The biopsy revealed granulomatous changes with multinucleated giant cells. We herein report this rare case and discuss the relevant literature.