Hypophysitis

Necrotizing infundibulo-hypophysitis: case-report and literature review

PURPOSE

We describe a rare case of histopathologic-proven necrotizing infundibulo-hypophysitis (NIH).

CLINICAL HISTORY

A 40-year-old female presented with coexistence of central diabetes insipidus and hypopituitarism. Imaging disclosed a thickened infundibulum and a diffusely enlarged pituitary mass with gadolinium rim enhancement pattern. Microsurgical endonasal transsphenoidal resection was performed. The presence of extensive liquefactive necrosis, surrounded by lymphoplasmocytic inflammatory infiltrate, allowed for the diagnosis of NIH. Follow-up cranial imaging 10 months after surgery showed no evidence of reappearance of the lesion. There was no progression to panhypopituitarism.

CONCLUSION

Surgery and histopathological confirmation are the key diagnostic feature in NIH. The current case is the fifth report of NIH and the first one with an indolent course and without progression to panhypopituitarism so far.

Hypopituitarism with secondary adrenocortical insufficiency and arginine vasopressin deficiency due to hypophysitis after COVID-19 vaccination: a case report

BACKGROUND

Although vaccination against coronavirus disease (COVID-19) has several side effects, hypopituitarism due to hypophysitis has rarely been reported.

CASE PRESENTATION

An 83-year-old healthy woman, who had received her fourth COVID-19 vaccine dose 2 days before admission, presented to the emergency department with difficulty moving. On examination, impaired consciousness (Glasgow Coma Scale: 14) and fever were observed. Computed tomography and magnetic resonance imaging of the head revealed swelling from the sella turcica to the suprasellar region. Her morning serum cortisol level was low (4.4 μg/dL) and adrenocorticotropic hormone level was normal (21.6 pg/mL). Central hypothyroidism was also suspected (thyroid stimulating hormone, 0.46 μIU/mL; free triiodothyronine, 1.86 pg/mL; free thyroxine, 0.48 ng/dL). Secondary adrenocortical insufficiency, growth hormone deficiency, delayed gonadotropin response, and elevated prolactin levels were also observed. After administration of prednisolone and levothyroxine, her consciousness recovered. On the 7th day of admission, the patient developed polyuria, and arginine vasopressin deficiency was diagnosed using a hypertonic saline test. On the 15th day, the posterior pituitary gland showed a loss of high signal intensity and the polyuria resolved spontaneously. On the 134th day, the corticotropin-releasing hormone loading test showed a normal response; however, the thyrotropin-releasing hormone stimulation test showed a low response. The patient's disease course was stable with continued thyroid and adrenal corticosteroid supplementation.

CONCLUSIONS

Herein, we report a rare case of anterior hypopituitarism and arginine vasopressin deficiency secondary to hypophysitis following COVID-19 vaccination.

[Differential diagnosis and tactics of managing a patient with primary hypophysitis on the example of a clinical case]

In recent years, there has been a significant increase in the prevalence of autoimmune endocrinopathies, which are known to affect various levels of the endocrine system, including the pituitary gland. Hypophysitis is a general term used to describe any form of sellar and suprasellar inflammation that leads to structural changes in the hypothalamic-pituitary region and manifests itself in varying degrees of hormonal deficiency of the anterior and posterior pituitary glands. To date, there is a primary form of hypophysitis, which occurs as a result of an autoimmune lesion directly to the pituitary gland, and a secondary form of hypophysitis, which occurs as a result of the presence of a systemic autoimmune disease. Regardless of the etiology, patients with hypophysitis show various signs and symptoms caused by an inflammatory process in the pituitary gland, which can lead to the development of hypopituitarism, compression of the sellar and parasellar structures. MRI is currently the best non-invasive diagnostic tool for diagnosing hypopituitarism, however, the diagnosis can be made with certainty only by histological examination of the pituitary tissue, which requires an invasive approach, which greatly reduces the feasibility of this procedure. In this article, we present a patient with MRI showing signs of hypophysitis in the absence of clear clinical symptoms.

Neoplasms and tumor-like lesions of the sellar region: imaging findings with correlation to pathology and 2021 WHO classification

The sellar region represents a complex anatomical area, composed of multiple structures of different embryological derivation, including the skull base and the pituitary gland, along with vascular, nervous, and meningeal structures. Masses arising in this region include benign and malignant lesions arising from the pituitary gland itself, but also from vestigial embryological residues or surrounding tissues, that may require different therapeutic approaches. While assessing sellar region masses, the combination of clinical presentation and imaging features is fundamental to define hypotheses about their nature. MR represents the imaging modality of choice, providing information about the site of the lesion, its imaging features, and relation with adjacent structures, while CT is useful to confirm the presence of lesion calcifications or to reveal tumor invasion of bony structures. The aim of this pictorial review is to provide an overview of the common neoplasms and tumor-like conditions of the sellar region, according to the 2021 WHO Classification of Tumors of the Central Nervous System (fifth edition), with an emphasis on the radiologic-pathologic correlation. After a brief introduction on the anatomy of this region and the imaging and pathological techniques currently used, the most relevant MRI characteristics, clinical findings, and pathological data, including histologic and molecular features, will be shown and discussed, with the aim of facilitating an appropriate differential diagnosis among these entities.

Frequency and clinical characteristics of hypophysitis and hypopituitarism in patients undergoing immunotherapy - A systematic review

OBJECTIVE

To describe the frequency of hypophysitis and hypopituitarism in cancer patients who are undergoing antineoplastic treatment with immunotherapy, as well as to describe the clinical, epidemiological, and demographic characteristics of these patients.

METHODS

A systematic search of the literature in PubMed, Embase, Web of Science, ClinicalTrials.gov and Cochrane Controlled Register of Trials took place on May 8 and 9, 2020. Randomized and nonrandomized clinical trials, cohort studies, case-control studies, case series and case reports were included.

RESULTS

A total of 239 articles were obtained, in which 963 cases of hypophysitis and 128 cases of hypopituitarism were found in a treated population of 30,014 individuals (3.20% and 0.42% of the evaluated population, respectively). In the cohort studies, the incidence of hypophysitis and hypopituitarism ranged from 0% to 27.59% and from 0% to 17.86%, respectively. In the non-randomized clinical trials, the incidence of hypophysitis and hypopituitarism ranged from 0% to 25% and from 0% to 14.67%, and in randomized clinical trials from 0% to 16.2% and from 0% to 33.33%. The most common hormonal changes were in the corticotrophic, thyrotrophic and gonadotrophic axes. The main magnetic resonance imaging (MRI) findings were enlargement of the pituitary gland and enhanced contrast uptake. The main symptoms presented by patients with hypophysitis were fatigue and headache.

CONCLUSION

The present review reported a frequency of hypophysitis and hypopituitarism of 3.20% and 0.42%, respectively, in the evaluated population. The clinical-epidemiological characteristics of patients affected by hypophysitis were also described.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier CRD42020175864.

Clinical Presentation of Immune-Related Endocrine Adverse Events during Immune Checkpoint Inhibitor Treatment

The exact clinical course and factors associated with persistent endocrine immune-related adverse events (irAEs) are not well-established. Elucidation of these information will aid irAEs screening and follow-up planning for patients on immunotherapy. We analysed the clinical course of endocrine irAEs including thyroid and pituitary dysfunction and insulin-dependent diabetes mellitus (IDDM), identified factors associated with persistent thyroid dysfunction, and determined the association between endocrine irAEs and survival parameters. This retrospective observational study enrolled patients with metastatic cancer who underwent anti-PD-1, anti-PD-L1, and/or anti-CTLA-4 treatment and developed endocrine irAE at the National University Cancer Institute, Singapore, between June 2015 and December 2020. Sixty-six patients with endocrine irAE were evaluated, with a median follow-up time of 15.7 months. The median time to onset of thyroid dysfunction, pituitary dysfunction, and IDDM was 1.8 months (range: 0.3–15.8 months), 6.8 months (range: 1.5–27.3 months), and 7.8 months (range: 1.4–9.1 months), respectively. Positive thyroperoxidase antibodies (TPOAb) and/ or thyroglobulin antibodies (TgAb) status at the time of thyroid dysfunction was associated with persistent thyroid dysfunction (OR 11.6, 95% CI 1.3–570.8, p = 0.02; OR 8.8, 95% CI 1.3–106.9, p = 0.01, respectively). All patients with pituitary irAE had central hypocortisolism. All patients with IDDM had grade 4 irAE. Patients with endocrine irAE had longer median survival times. Endocrine irAEs were associated with nonprogressive disease. The screening and follow-up approach for endocrine irAEs should be tailored according to each endocrinopathy’s clinical course. Early screening is imperative given its wide median time to onset.

Paraneoplastic autoimmune hypophysitis: An emerging concept

Pituitary autoimmunity is one of the principal causes of hypopituitarism. Additionally, hypophysitis is one of the immune-related adverse events associated with immunotherapy. Recent case-oriented research has revealed a novel type of autoimmune hypophysitis, anti-PIT-1 hypophysitis, related to isolated adrenocorticotropic hormone (ACTH) deficiency and immune checkpoint inhibitor-related hypophysitis, as a form of paraneoplastic syndrome. Under these conditions, the ectopic expression of pituitary antigens present in tumors evokes a breakdown of immune tolerance, resulting in the production of autoantibodies and autoreactive cytotoxic T cells that specifically harm pituitary cells. Consequently, an innovative clinical entity of paraneoplastic autoimmune hypophysitis has been purported. This novel concept and its underlying mechanisms provide clues for understanding the pathogenesis of autoimmune pituitary diseases and can be applied to other autoimmune diseases. This review discusses the etiology of paraneoplastic autoimmune hypophysitis and its future.

Immune checkpoint inhibitor-related hypophysitis

Immune checkpoint inhibitors (ICIs) have been recently proposed as a strategy for treating anti-malignant neoplasms. However, this treatment leads to immune-related adverse events (irAEs) such as autoimmune endocrinopathy. Early diagnosis and appropriate treatment of ICI-related hypophysitis are essential as it can manifest as a life-threatening condition due to an adrenal crisis. In this review, we summarize the pathogenesis, risk factors, diagnostic processes, clinical characteristics, and its current management. In particular, we discuss the different aspects of anti-CTLA-4 antibody-related and anti-PD-1/anti-PD-L1 antibody-related hypophysitis. We also propose key points for early detection and diagnosis by identifying the target group that should be monitored more carefully. Specific methods of hormone replacement therapy have also been described. We hope that this review will lead to a better understanding and management of this rare but serious condition during cancer treatment and further elucidate the pathophysiology of pituitary autoimmunity.

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.

Complete Resolution of the Pituitary Mass Lesion and Improvement of Pituitary Function with Corticosteroid in Autoimmune Hypophysitis: A Case Report

BACKGROUND

Autoimmune hypophysitis is the consequence of an immune-mediated inflammation of the pituitary gland, which is rare, and most frequently occurs in females during postpartum periods. It usually responds well to corticosteroid treatment with reported resolution of the pituitary mass lesion.

CASE REPORT

A 51 years male presented with a one-month history of lethargy, headache, nausea, proximal muscle weakness with intermittent flushing. He was a diabetic with metformin 500mg twice daily. No other remarkable medical history or family history of autoimmune disease. On examination, he had no neurological deficit with a normal visual field. His initial biochemical evaluation showed features of secondary hypothyroidism as evidenced by low free FT4 and suppressed TSH with normal electrolytes. The subsequent evaluation of his hormonal profile revealed panhypopituitarism. Contrast MRI of pituitary showed an enhanced homogenous mass and minimal stalk thickening with a dural tail and preserved posterior bright spot. He was managed with glucocorticoid 20 mg once daily for two weeks along with levothyroxine and testosterone replacement. After two weeks of treatment, he improved clinically. Repeat MRI imaging of the pituitary showed complete resolution of the homogenous mass.

CONCLUSION

Although autoimmune hypophysitis is rare in males, a careful clinical history with necessary hormonal investigations is required for the suspicion about the inflammatory pituitary disorders This current case highlights glucocorticoid as the primary modality of treatment and the need for long-term follow-up with periodic clinical assessment.

Clinical presentation and management of hypophysitis: An observational study of case series

Background:

Hypophysitis is described as a rare chronic inflammatory affection of the pituitary gland. However, to date, its pathogenesis has not been completely cleared up. Clinical features are polymorphic, including symptoms related to inflammatory compression and/or hypopituitarism. Laboratory tests determine hormone deficiencies orientating replacement therapy’s protocol. MRI of the hypothalamic-pituitary region is crucial in exhibiting major radiological signs such as pituitary homogeneous enlargement and gland stalk’s thickening. The etiological diagnosis is still challenging without affecting the management strategy. Corticosteroids have widely been used but a close follow-up without any treatment has also been approved.

Case Description:

In this report, seven patients with hypophysitis have been collected over a period of 6 years. The average age of our patients was 32.1 years ± 11.8 with a female predominance (71.4%). Panhypopituitarism was objective in 42.9% of cases, a combined deficiency of the hypothalamic-pituitary thyroid, adrenal and gonadal axes in 28.6% of cases. A central diabetes insipidus was noted in 42.9% of the patients. Idiopathic hypophysitis was the most common etiology. The use of long course corticosteroids was required in 28.6% when compressive signs were reported.

Conclusion:

Hypophysitis remains a rare disease with nonspecific clinical and radiological patterns. Autoimmune origin seems to be the most frequent etiology. No guidelines have been established for hypophysitis management and the evolution is still unpredictable.

IgG4-related hypophysitis

Hypophysitis is a rare pituitary inflammatory disorder classified in different ways. Immunoglobulin G4-related disease (IgG4-RD), also a rare disease is a systemic fibro-inflammatory condition characterized by infiltration of tissue with IgG4-positive plasma cells; however prevalence of both of them probably is underestimated. In this paper, we present an Iranian patient with biopsy-proven IgG4-related hypophysitis and then review the clinical characteristics, laboratory, imaging, pathologic findings and therapeutic management as well as prognosis of 115 published cases of hypophysitis secondary to IgG4-related disease.

The hypothalamus-pituitary-thyroid (HPT)-axis and its role in physiology and pathophysiology of other hypothalamus-pituitary functions

The hypothalamus-pituitary-thyroid axis is one of several hormone regulatory systems from the hypothalamus to the pituitary and ultimately to the peripheral target organs. The hypothalamus and the pituitary gland are in close anatomical proximity at the base of the brain and extended through the pituitary stalk to the sella turcica. The pituitary stalk allows passage of stimulatory and inhibitory hormones and other signal molecules. The target organs are placed in the periphery and function through stimulation/inhibition by the circulating pituitary hormones. The several hypothalamus-pituitary-target organ axis systems interact in very sophisticated and complicated ways and for many of them the interactive and integrated mechanisms are still not quite clear. The diagnosis of central hypothyroidism is complicated by itself but challenged further by concomitant affection of other hypothalamus-pituitary-hormone axes, the dysfunction of which influences the diagnosis of central hypothyroidism. Treatment of both the central hypothyroidism and the other hypothalamus-pituitary axes also influence the function of the others by complex mechanisms involving both central and peripheral mechanisms. Clinicians managing patients with neuroendocrine disorders should become aware of the strong integrative influence from each hypothalamus-pituitary-hormone axis on the physiology and pathophysiology of central hypothyroidism. As an aid in this direction the present review summarizes and highlights the importance of the hypothalamus-pituitary-thyroid axis, pitfalls in diagnosing central hypothyroidism, diagnosing/testing central hypothyroidism in relation to panhypopituitarism, pointing at interactions of the thyroid function with other pituitary hormones, as well as local hypothalamic neurotransmitters and gut-brain hormones. Furthermore, the treatment effect of each axis on the regulation of the others is described. Finally, these complicating aspects require stringent diagnostic testing, particularly in clinical settings with lower or at least altered à priori likelihood of hypopituitarism than in former obvious clinical patient presentations.

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.

Primary and Ipilimumab-induced Hypophysitis: A Single-center Case Series

PURPOSE

To present a case series of primary and immunotherapy-related secondary hypophysitis.

METHODS

A single-center retrospective chart review was performed at the University of British Columbia, Vancouver, Canada. Eleven cases of primary hypophysitis and 2 cases of immunotherapy-related secondary hypophysitis were included. Of the 11 primary cases, 6 were diagnosed clinically without biopsy.

RESULTS

In primary hypophysitis, headache was the most common presenting symptom (6/11; 55%) and stalk enlargement the prevailing radiologic sign (8/11; 73%). Central adrenal insufficiency (4/11; 36%), central hypothyroidism (4/11; 36%), and central diabetes insipidus (CDI) (4/11; 36%) were the most common pituitary deficiencies at presentation. Initial management included surgery (4/11; 36%), supraphysiologic steroids (2/11; 18%), or observation (6/11; 55%). Outcomes assessed included radiologic improvement (8/9; 89%), improvement in mass symptoms (4/7; 57%), anterior pituitary recovery (1/7; 14%), and CDI recovery (0/4; 0%). In immunotherapy-related hypophysitis either under observation or supraphysiologic steroid therapy, the inflammatory mass resolved and pituitary dysfunction persisted.

CONCLUSIONS

In primary hypophysitis, the inflammatory pituitary mass typically resolves and hypopituitarism persists. In the absence of severe or progressive neurologic deficits, a presumptive clinical diagnosis and conservative medical management should be attempted. In the absence of severe features, immunotherapy-related hypophysitis may be managed effectively without the use of supraphysiologic steroids.

Managing Ipilimumab-Induced Hypophysitis: Challenges and Current Therapeutic Strategies

Over the past years, progress has been made in cancer immunotherapy following the development of immune checkpoint inhibitors (ICI) that have been proved effective in the management of many malignancies. Ipilimumab, a monoclonal antibody against cytotoxic T-lymphocyte antigen-4 (CTLA-4), has been approved for the treatment of advanced melanoma but has been associated with the development of several endocrine immune-related adverse events (irAEs). Hypophysitis is the most common endocrine irAE related to ipilimumab with a reported incidence ranging from 1.8% to 17%. The mechanism underlying ipilimumab-induced hypophysitis implicates immune, inflammatory and genetic factors, but there are still some points that are not well understood and remain to be elucidated. The diagnosis is based mainly on clinical, biochemical and imaging data. The majority of patients display multiple hormone deficiencies that may recover or persist for a prolonged period of time with corticotroph deficiency usually being permanent. Immune-related hypopituitarism is treated with replacement of deficient hormones while in severe forms of hypophysitis treatment with high-dose glucocorticoids may be required. Proper evaluation and registration of patients in clinical trials and further investigation are needed to precisely clarify the pathophysiology of the ICI-related hypophysitis, define predictive factors and ameliorate the management and outcome of the disease.

Remission of Pituitary Autoimmunity Induced by Gluten-Free Diet in Patients With Celiac Disease

CONTEXT

An improvement of some autoimmune diseases associated with celiac disease (CD) has been observed after a gluten-free diet (GFD).

OBJECTIVE

The aim of this longitudinal study was to evaluate the effect of a GFD on autoimmune pituitary impairment in patients with CD and potential/subclinical lymphocytic hypophysitis (LYH).

DESIGN

Five-year longitudinal observational study.

SETTING

Tertiary referral center for immunoendocrinology at the University of Campania "Luigi Vanvitelli".

PATIENTS

Ninety-three newly diagnosed LYH patients (high titer of antipituitary antibodies [APA] and normal or subclinically impaired pituitary function) were enrolled from 2000 to 2013 and grouped as follows: group 1, consisting of 43 patients with LYH + CD, and group 2, consisting of 50 patients with isolated LYH only.

INTERVENTION

A GFD was started in patients in group 1 after the diagnosis of CD.

MAIN OUTCOME MEASURES

APA titers and pituitary function were evaluated at the beginning of the study and then yearly for 5 years in both groups. Patients progressing to a clinically overt LYH were excluded from the follow-up.

RESULTS

Complete remission of LYH (disappearance of APA and recovery of pituitary function in patients with previous subclinical hypopituitarism) occurred in 15 patients in group 1 after a GFD (34%) and spontaneously in only 1 patient in group 2 (2%) (P < .001). Two patients in group 1 and 25 in group 2 progressed to a clinically overt hypopituitarism and dropped out from the study to receive an appropriate replacement therapy. The presence of CD was the only independent predictor of pituitary function recovery (hazard ratio [HR] 0.059, 95% confidence interval [CI] 0.01-0.54, P = .012).

CONCLUSION

In patients with LYH and CD, a GFD may be able to induce remission of subclinical LYH, or prevent the progression to clinical stage of this disease.

Management of immune checkpoint inhibitor-related adverse events: A review of case reports

Immune checkpoint inhibitors represent a major breakthrough in cancer therapy. Immune‐related adverse events (irAEs) may occur during treatment due to their unique mechanism of action. Management of irAEs is based on clinical experience because it is not easy to conduct prospective trials to evaluate the best treatment strategy. Using a combination of search terms in the PubMed and Embase databases, we reviewed all cases in the English language citing toxicities associated with either pembrolizumab, nivolumab, ipilimumab, atezolizumab, tremelimumab, durvalumab, avelumab or any combination of these agents published before 20 May 2019. A total of 128 reports with 239 cases were included in the study. Here, we summarize the spectrum of toxicities, safety in special patients, rechallenging after irAEs and agents used for treatment of irAEs in those reports.

Intracranial Germinoma Masquerading as Secondary Granulomatous Hypophysitis: A Case Report and Review of Literature

Germinomas are highly immunogenic tumors eliciting a strong peri-tumoral immune response that can spillover into the surrounding healthy tissues. This phenomenon can also occur in intracranial germinomas, manifesting as secondary hypophysitis. Herein, we report a case of 12-year-old-girl presenting with polyuria and polydispsia. She had central diabetes insipidus (CDI) and panhypopituitarism. Imaging revealed a sellar-suprasellar mass with infundibular stalk thickening. Transphenoidal biopsy revealed epithelioid granulomas with immunostaining negative for germinomatous cells. Other causes of hypophysitis were ruled out. Accordingly, she was diagnosed as primary granulomatous hypophysitis and treated with high-dose corticosteroids. Three years later she again presented with headache, vomiting and diminution of vision. Imaging showed a heterogeneous, solid-cystic peripheral rim-enhancing lesion at the same location with involvement of hypothalamus, ependyma and pineal gland. Cerebrospinal fluid beta-human chorionic gonadotropin was markedly elevated, confirming the diagnosis of an intracranial germ cell tumor. She was started on chemotherapy; however, she succumbed to febrile neutropenia. We performed a literature search and found 18 anecdotal cases of secondary hypophysitis associated with intracranial germinomas. There was a slight male preponderance (male:female 5:4). Two-thirds of the cases were below 18 years of age. Polyuria was the most common presenting manifestation (83%). CDI and panhypopituitarism were seen in 89 and 78% cases, respectively. Imaging evidence of pituitary stalk thickening was seen in 12 cases (67%), while pituitary enlargement and/or sellar mass were reported in 11 cases (61%). Pineal involvement was extremely rare, being reported in only 1 case, implying the predilection of suprasellar (rather than pineal) germinomas in causing secondary hypophysitis. Histologically, 82% had lymphocytic hypophysitis, while 18% had granulomatous hypophysitis. Initially, the diagnosis of germinoma was missed in 60% of the cases who were wrongly treated with corticosteroids. To conclude, physicians should make it a dictum that all children and adolescents presenting with CDI and pituitary stalk thickening should be rigorously screened for an underlying intracranial germinoma before labeling them as primary hypophysitis.

Autoimmune phenomena involving the pituitary gland in children: New developing data about diagnosis and treatment

The contribution of autoimmune phenomena to dysfunction of hypophysis or hypothalamus is far to be unraveled and also the specific pathways of hypophysitis are poorly understood until now, mostly for the pediatric population. Primary hypophysitis is rare in children and often regarded as an autoimmune disorder, following the evidence of lymphoplasmacytic infiltration in the pituitary gland, detection of anti-pituitary antibodies (APA) and anti-hypotalamus antibodies (AHA) by indirect immunofluorescence on cryostatic sections of human or primate hypophysis and hypothalamus, and coexistence with other autoimmune disorders. The rarity of this condition and the lack of ad hoc studies make hard any assessment of the real incidence of hypophysitis in pediatric patients, and also the role of APA and AHA has been poorly investigated in children with idiopathic hypopituitarism. Potential target autoantigens studied in autoimmune hypophysitis have been various pituitary-specific factors, chaperone proteins, alpha-enolase, secretogranins, chorionic somatomammotropin and intracellular transcription factors. Many clinical features both endocrine and neurologic or systemic can herald the onset of autoimmune hypophysitis. Antidiuretic hormone deficiency with central diabetes insipidus and growth retardation are the most significant presenting symptoms in children with hypophysitis, requiring a careful differential diagnosis with other causes of hypopituitarism, including tumors of the sellar region, differently from adults in whom adrenal insufficiency, hypogonadism, headache or diplopia might be the leading manifestations. Growth hormone deficiency is found in 3/4 of pediatric cases. Five histologic variants of primary hypophysitis have been described: lymphocytic, granulomatous, xanthomatous, IgG4-related and necrotizing: lymphocytic hypophysitis is the most frequent variant in the pediatric sceneries. Children with diagnosis of hypophysitis are also at risk of developing germinomas later in life, and require an extended follow-up in the long-term. Therapeutic options should be differentiated according to the rapidity of disease progression and modality of clinical onset, as acute pictures might require corticosteroids or immunosuppressant agents, while chronic forms may need a conservative management or appropriate hormone replacement therapies. This review updates and summarizes the most recent information related to the autoimmune involvement of hypophysis and hypothalamus in children, discusses the correlations between APA, AHA and disease activity, as well as the recommendations for treatment of primary hypophysitis from the pediatric perspective.

The Changing Clinical Spectrum of Hypophysitis

Hypophysitis is a rare and potentially life-threatening disease, characterized by an elevated risk of complications, such as occurrence of acute central hypoadrenalism, persistent hypopituitarism, or extension of the inflammatory process to the neighboring neurological structures. In recent years, a large number of patients have been described as being affected by hypophysitis, due to the increased administration of immuno-chemotherapies. At the present time, the heterogeneous nature of hypophysitis diagnostic criteria and of the treatment protocols makes the management of affected patients difficult. We review the current data and evidence on primary and secondary hypophysitis, in order to suggest a diagnostic and therapeutic protocol that should be focused on a multidisciplinary approach, for reaching a prompt diagnosis and an appropriate and safe treatment.

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.

Nivolumab-induced hypothyroidism followed by isolated ACTH deficiency

Cancer immunotherapy has been used in several malignancies with clinical benefit. Despite the clinical success, immune-related adverse events are frequent and endocrinopathies can be particularly severe. We report a 55-year-old male patient with stage IV pulmonary carcinoma treated with nivolumab who presented with thyroid dysfunction after the sixth administration of the drug. One year after thyroid dysfunction, the patient complained of severe fatigue, asthenia and weight loss. Laboratory testing showed low morning cortisol with undetected adrenocorticotropic hormone; other pituitary hormones were normal and MRI showed homogeneous enhancement of the pituitary gland and no space-occupying lesions. The diagnosis of nivolumab-induced hypophysitis was made and replacement treatment with hydrocortisone was started with clinical improvement. This case demonstrates that patients under immunotherapy are at risk for a large spectrum of endocrine dysfunctions that may worsen their prognosis. Close monitoring of these patients is warranted.

Hypophysitis in the era of immune checkpoint inhibitors and immunoglobulin G4-related disease

INTRODUCTION

Hypophysitis is a rare disorder, defined as inflammation of the pituitary gland that may result in pituitary enlargement and varying anterior and posterior pituitary hormonal deficits. It involves different histopathological subtypes and variable etiologies, with considerable overlap between classification systems. Histopathology is the gold standard diagnostic approach.

AREAS COVERED

In this article, we will review the major histopathological subtypes of hypophysitis with a special focus on immunoglobulin G4 (IgG4)-related hypophysitis and immune checkpoint inhibitor-induced hypophysitis, given their recent appearance and increasing incidence. We will summarize the similarities and differences between the different subtypes as it relates to epidemiology, pathogenesis, presentation, diagnosis, and management.

EXPERT OPINION

Hypophysitis is a heterogeneous and wide term used to describe different, possibly distinct diseases often with poorly understood pathogenesis. It involves a wide range of subtypes with certain differences in incidence rates, pathogenesis, and management. Management usually focuses on relieving the mass effect symptoms and replacing the deficient pituitary hormones. Spontaneous recovery is possible but recurrence is not uncommon.

Endocrine Toxicity of Cancer Immunotherapy Targeting Immune Checkpoints

Immune checkpoints are small molecules expressed by immune cells that play critical roles in maintaining immune homeostasis. Targeting the immune checkpoints cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed death 1 (PD-1) with inhibitory antibodies has demonstrated effective and durable antitumor activity in subgroups of patients with cancer. The US Food and Drug Administration has approved several immune checkpoint inhibitors (ICPis) for the treatment of a broad spectrum of malignancies. Endocrinopathies have emerged as one of the most common immune-related adverse events (irAEs) of ICPi therapy. Hypophysitis, thyroid dysfunction, insulin-deficient diabetes mellitus, and primary adrenal insufficiency have been reported as irAEs due to ICPi therapy. Hypophysitis is particularly associated with anti-CTLA-4 therapy, whereas thyroid dysfunction is particularly associated with anti-PD-1 therapy. Diabetes mellitus and primary adrenal insufficiency are rare endocrine toxicities associated with ICPi therapy but can be life-threatening if not promptly recognized and treated. Notably, combination anti-CTLA-4 and anti-PD-1 therapy is associated with the highest incidence of ICPi-related endocrinopathies. The precise mechanisms underlying these endocrine irAEs remain to be elucidated. Most ICPi-related endocrinopathies occur within 12 weeks after the initiation of ICPi therapy, but several have been reported to develop several months to years after ICPi initiation. Some ICPi-related endocrinopathies may resolve spontaneously, but others, such as central adrenal insufficiency and primary hypothyroidism, appear to be persistent in most cases. The mainstay of management of ICPi-related endocrinopathies is hormone replacement and symptom control. Further studies are needed to determine (i) whether high-dose corticosteroids in the treatment of ICPi-related endocrinopathies preserves endocrine function (especially in hypophysitis), and (ii) whether the development of ICPi-related endocrinopathies correlates with tumor response to ICPi therapy.

Less known aspects of central hypothyroidism: Part 1 - Acquired etiologies

Central hypothyroidism (CH) is a rare cause of hypothyroidism. CH is frequently overlooked, as its clinical picture is subtle and includes non-specific symptoms; furthermore, if measurement of TSH alone is used to screen for thyroid function, TSH concentrations can be normal or even above the upper normal reference limit. Indeed, certain patients are at risk of developing CH, such as those with a pituitary adenoma or hypophysitis, those who have been treated for a childhood malignancy, have suffered a head trauma, sub-arachnoid hemorrhage or meningitis, and those who are on drugs capable to reduce TSH secretion.

Hypophysitis Outcome and Factors Predicting Responsiveness to Glucocorticoid Therapy: A Prospective and Double-Arm Study

CONTEXT

Primary autoimmune hypophysitis (PAH) evolves in most untreated cases in irreversible hypopituitarism. PAH outcome, instead, after immunosuppressive treatment has not been completely clarified.

OBJECTIVE

To evaluate hypophysitis and pituitary function outcomes.

DESIGN

A prospective, double-arm study with a 2-year follow-up.

SETTING

Referral center for pituitary disease.

PATIENTS

Twenty PAH cases.

INTERVENTIONS

Oral prednisone 50 mg/d or conservative strategy by observation.

MAIN OUTCOME MEASURES

Primary endpoint was the improvement/stabilization/worsening of PAH from baseline to a 2-year visit. Secondary endpoint was the improvement/stabilization/worsening of pituitary function from baseline to a 2-year visit.

RESULTS

Twelve patients (57.1%) were treated with a glucocorticoid-immunosuppressive therapy, and eight patients (42.9%) were observed. At the 2-year visit, PAH improvement/recovery occurred in eight immunosuppressive-treated (66.7%) patients and in two untreated patients (25%). PAH worsened in three untreated patients (37.5%) and was considered stable in four immunosuppressive-treated (33.3%) and three untreated patients (37.5%). Improvement/recovery of pituitary function occurred more frequently in immunosuppressive-treated patients (58.3%) compared with untreated ones (25%; P = 0.04). Responsiveness to immunosuppressive treatment is correlated with antipituitary antibody presence (P = 0.01), occurrence of diabetes insipidus at PAH diagnosis (P = 0.01), absence of the physiological neuropituitary "bright spot" on T1-weighed images (P = 0.01), and pituitary stalk at optical chiasm larger than 3.9 mm (area under the curve: 0.97, sensibility: 100%, specificity: 100%; P = 0.04). On the other hand, we failed to identify factors predicting the outcome, among untreated patients.

CONCLUSIONS

Glucocorticoid treatment of hypophysitis improves pituitary secretion and should be encouraged in accordance with the evaluation of endocrine-, immunological-, and morphological-predictive markers.

MECHANISMS IN ENDOCRINOLOGY: Hypophysitis: diagnosis and treatment

Hypophysitis is a rare condition characterised by inflammation of the pituitary gland, usually resulting in hypopituitarism and pituitary enlargement. Pituitary inflammation can occur as a primary hypophysitis (most commonly lymphocytic, granulomatous or xanthomatous disease) or as secondary hypophysitis (as a result of systemic diseases, immunotherapy or alternative sella-based pathologies). Hypophysitis can be classified using anatomical, histopathological and aetiological criteria. Non-invasive diagnosis of hypophysitis remains elusive, and the use of currently available serum anti-pituitary antibodies are limited by low sensitivity and specificity. Newer serum markers such as anti-rabphilin 3A are yet to show consistent diagnostic value and are not yet commercially available. Traditionally considered a very rare condition, the recent recognition of IgG4-related disease and hypophysitis as a consequence of use of immune modulatory therapy has resulted in increased understanding of the pathophysiology of hypophysitis. Modern imaging techniques, histological classification and immune profiling are improving the accuracy of the diagnosis of the patient with hypophysitis. The objective of this review is to bring readers up-to-date with current understanding of conditions presenting as hypophysitis, focussing on recent advances and areas for future development. We describe the presenting features, investigation and diagnostic approach of the patient with likely hypophysitis, including existing conventional techniques and those in the research/development arena. Hypophysitis usually results in acute and persistent pituitary hormone deficiency requiring long-term replacement. Management of hypophysitis includes control of the inflammatory pituitary mass using a variety of treatment strategies including surgery and medical therapy. Glucocorticoids remain the mainstay of medical treatment but other immunosuppressive agents (e.g. azathioprine, rituximab) show benefit in some cases, but there is a need for controlled studies to inform practice.

Intrachiasmatic abscess caused by IgG4-related hypophysitis

INTRODUCTION

Autoimmune hypophysitis is a rare disease of the pituitary, which may affect vision by inflammation and compression of the optic chiasm. However, intrachiasmatic abscess formation has not been previously reported.

METHODS

In this study, we report a case of a 29-year-old female with bitemporal hemianopia due to a cystic intrasellar tumor. The patient underwent surgical decompression of the lesion, which was found to be an intrachiasmatic abscess.

RESULTS

The histologic findings were consistent with IgG4 hypophysitis.

CONCLUSION

This rare clinical presentation suggests that in case of a disproportionate degree of visual impairment in relation to the size of the lesion, suspicion should lead to an intrachiasmatic lesion.

Primary hypothyroidism and isolated ACTH deficiency induced by nivolumab therapy: Case report and review

RATIONALE

Nivolumab is a monoclonal IgG antibody blocking programmed death receptor-1 (PD1), leading to restoration of the natural T-cell-mediated immune response against the cancer cells. However, it also causes plenty of autoimmune-related adverse events, which often involves endocrine system.

PATIENT CONCERNS

A 54-year-old male with renal clear cell carcinoma was treated with nivolumab intravenously. Routine monitoring showed elevated thyroid-stimulating hormone and low free thyroxine after the 6th administration of nivolumab. After the 12th administration, he developed general fatigue, recurrent hypoglycemia, and relative hypotension. Laboratory tests showed low sodium, low morning cortisol without correspondence increase of corticotrophin (ACTH). Other pituitary hormones were normal. MRI showed no space-occupying lesions, but heterogeneous enhancement of the pituitary gland.

DIAGNOSES

Primary hypothyroidism and isolated ACTH deficiency. The etiologies were assumed to be nivolumab induced autoimmune lymphocytic thyroiditis and hypophysitis, respectively.

INTERVENTIONS

Hormone replacements with levothyroxine and acetate cortisone were given orally. Nivolumab was adjusted to lower dose and longer interval.

OUTCOMES

The patient felt good after adequate replacement. Nivolumab was returned to routine dose and interval six months later. And the metastasis was not obviously progressed during this time.

LESSONS

The present report provides the first detailed presentation of combined hypothyroidism and isolated ACTH deficiency induced by nivolumab. Adrenal deficiency often develops insidiously. We suggest routine monitoring of fasting blood-glucose, blood pressure and serum sodium as well as thyroid function during nivolumab and other cancer immunotherapies. When unexpected fatigue, hypoglycemia, hypotension or hyponatremia appeared, adrenal deficiency should be taken into consideration.

Central hypothyroidism - a neglected thyroid disorder

Central hypothyroidism is a rare and heterogeneous disorder that is characterized by a defect in thyroid hormone secretion in an otherwise normal thyroid gland due to insufficient stimulation by TSH. The disease results from the abnormal function of the pituitary gland, the hypothalamus, or both. Moreover, central hypothyroidism can be isolated or combined with other pituitary hormone deficiencies, which are mostly acquired and are rarely congenital. The clinical manifestations of central hypothyroidism are usually milder than those observed in primary hypothyroidism. Obtaining a positive diagnosis for central hypothyroidism can be difficult from both a clinical and a biochemical perspective. The diagnosis of central hypothyroidism is based on low circulating levels of free T₄ in the presence of low to normal TSH concentrations. The correct diagnosis of both acquired (also termed sporadic) and congenital (also termed genetic) central hypothyroidism can be hindered by methodological interference in free T₄ or TSH measurements; routine utilization of total T₄ or T₃ measurements; concurrent systemic illness that is characterized by low levels of free T₄ and normal TSH concentrations; the use of the sole TSH-reflex strategy, which is the measurement of the sole level of TSH, without free T₄, if levels of TSH are in the normal range; and the diagnosis of congenital hypothyroidism based on TSH analysis without the concomitant measurement of serum levels of T₄. In this Review, we discuss current knowledge of the causes of central hypothyroidism, emphasizing possible pitfalls in the diagnosis and treatment of this disorder.

[Primary and secondary hypophysitis: A clinicomorphological study]

The paper describes 6 cases of the rare disease - primary and secondary hypophysitis detected by a morphological examination of the material of endoscopic transsphenoidal resection of pituitary neoplasms. It also provides clinical and morphological comparisons and analyzes the data available in the literature.

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.

Autoimmune polyendocrinopathy and hypophysitis after Puumala hantavirus infection

Puumala hantavirus (PUUV) infection causes nephropathia epidemica (NE), a relatively mild form of haemorrhagic fever with renal syndrome (HFRS). Hypophyseal haemorrhage and hypopituitarism have been described in case reports on patients with acute NE. Chronic hypopituitarism diagnosed months or years after the acute illness has also been reported, without any signs of a haemorrhagic aetiology. The mechanisms leading to the late-onset hormonal defects remain unknown. Here, we present a case of NE-associated autoimmune polyendocrinopathy and hypopituitarism presumably due to autoimmune hypophysitis. Thyroid peroxidase antibody seroconversion occurred between 6 and 12 months, and ovarian as well as glutamate decarboxylase antibodies were found 18 months after acute NE. Brain MRI revealed an atrophic adenohypophysis with a heterogeneous, low signal intensity compatible with a sequela of hypophysitis. The patient developed central (or mixed central and peripheral) hypothyroidism, hypogonadism and diabetes insipidus, all requiring hormonal replacement therapy. This case report suggests that late-onset hormonal defects after PUUV infection may develop by an autoimmune mechanism. This hypothesis needs to be confirmed by prospective studies with sufficient numbers of patients.

Immunotherapy and hypophysitis: clinical presentation, treatment, and biologic insights

INTRODUCTION

Advances in immunotherapy have transformed the management of metastatic melanoma and generated encouraging results in the treatment of other malignancies. Autoimmune side effects from these agents, termed immune-related adverse events (IRAEs), are diverse and can include multiple endocrinopathies. Ipilimumab-induced hypophysitis (IH) is a recently recognized endocrine IRAE.

METHODS

This review summarizes published data and experience from our center on the incidence, presentation and management, and proposed mechanisms for immunotherapy-related hypophysitis, with a focus on patients treated with ipilimumab (Ipi).

CONCLUSION

Hypophysitis occurs in a significant minority of patients treated with Ipi, in contrast to the relative rarity of idiopathic autoimmune hypophysitis or hypophysitis after treatment with other immunotherapies. Recently published cohorts have described the clinical presentation and management of IH and longitudinal outcomes in these patients. Additional studies with Ipi and other emerging agents have helped identify potential risk factors for the development of immunotherapy-related hypophysitis and possible underlying mechanisms for IH. Clarification of the mechanism(s) for IH may enhance our understanding of idiopathic autoimmune hypophysitis and could have potential therapeutic applications.

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.