[Pituitary cryptococcoma: a strange case of secondary granulomatous hypophysitis]. / Cryptococcoma hipofisiario: un extraño caso de hipofisitis granulomatosa secundaria.

Hypophysitis is a pathology with low incidence and prevalence. Likewise, deep fungal infections in immunocompetent patients also represent a rare phenomenon. Even rarer is the case described below, where these two mentioned elements are combined, namely: pituitary cryptococcoma or granulomatous hypophysitis caused by said pathogen in a host without altered immune response. After research in PubMed, there are limited cases in the medical literature of granulomatous hypophysitis caused by Cryptococcus spp., which simulated a pituitary macroadenoma by clinical and imaging manifestations. We did not find reports in which there is no evidence of involvement of the meningeal tissue. The fungal etiology is scarcely described in the reference guidelines for hypophysitis and we believe that Cryptococcus spp. it should be taken into account in the differential diagnosis of secondary granulomatous hypophysitis since it is a ubiquitous pathogen and the treatment is substantially different from other entities. It becomes more relevant given the current trend towards the use of high-dose systemic glucocorticoids for the treatment of hypophysitis, which could have generated greater damage if the correct diagnosis had not been made.

La hipofisitis es una afección con baja incidencia y prevalencia. Asimismo, las infecciones profundas por hongos en pacientes inmunocompetentes también representan un fenómeno infrecuente. Más raro aún es el caso que se describe a continuación, en donde se conjugan estos dos elementos mencionados, a saber: cryptococcoma hipofisario o hipofisitis granulomatosa causado por dicho patógeno en un huésped sin alteración de la respuesta inmune. Luego de una búsqueda realizada en PubMed, existen limitados casos en la literatura médica de hipofisitis granulomatosa por Cryptococcus spp., que simuló por manifestaciones clínicas e imagenológicas un macroadenoma hipofisario. No encontramos informes en los que no haya evidencia de afectación del tejido meníngeo. La etiología micótica está escasamente descrita en las guías de referencia para hipofisitis y creemos que Cryptococcus spp. debe ser tenido en cuenta en el diagnóstico diferencial de las hipofisitis granulomatosas secundarias dado que es un patógeno ubicuo y el tratamiento es sustancialmente diferente a otras entidades. Cobra mayor relevancia ante la tendencia actual al uso de glucocorticoides sistémicos a altas dosis para el tratamiento de la hipofisitis, que podría haber generado mayor daño de no haberse hecho el diagnóstico correcto.

[Primary hypophysitis: diagnosis and treatment multicenter study]. / Hipofisitis primaria: diagnóstico y tratamiento. Estudio multicéntrico.

INTRODUCTION: Primary hypophysitis (PH) is a rare disease that represents a challenge among differential diagnosis and management. Our aim was to describe clinical characteristics, diagnostic criteria and different treatment outcomes in patients with PH. Multicentric, retrospective study. Clinical presentation, endocrine function, magnetic resonance imaging findings, visual field defects at diagnosis and treatment outcomes were recorded. METHODS: Twenty-eight patients (23 women), with PH were included. Median age: 37. RESULTS: The most frequent symptoms: headache: 68%, polyuria-polydipsia: 50% and visual disturbances: 48%. At diagnosis, anterior pituitary deficiency was present in 71%, being hypogonadotrophic hypogonadism the most frequent manifestation. The radiological findings: symmetric lesion: 78.5%, homogeneous enhancement: 78.5% and pituitary stalk thickening: 70%. Association with pregnancy or puerperium was found in 4/23 women (17%). Fourteen patients did not receive any treatment ("wait and see" group), 8 underwent surgery for mass reduction or resection and 6 were treated with immunosuppression therapy. Among 15 patients with histopathological diagnosis, 9 were lymphocytic hypophysitis, 5 IgG4 related hypophysitis and 1 xanthomatous hypophysitis. Thirteen were diagnosed by established clinical criteria. Mass reduction was observed in 43% of "wait and see group" patients, 62.5% of operated patients and 50% with immunosuppression therapy. Compressive symptoms showed improvement in the 3 groups, with modest effect on anterior pituitary function, diabetes insipidus did not resolve in any patients. DISCUSSION: In patients without severe compressive symptoms, we adopted a "wait and see" approach. In patients with uncertain diagnosis of PH or severe compressive symptoms, transsphenoidal surgery was the best option.

Introducción: La hipofisitis es una enfermedad infrecuente que plantea un desafío en el diagnóstico y tratamiento. El objetivo de este estudio multicéntrico y retrospectivo fue describir: a) características de pacientes con hipofisitis primaria (HP), b) métodos diagnósticos, y c) tratamientos realizados. Además, evaluar: a) presentación clínica, b) bioquímica, c) radiológica, d) oftalmológica al diagnóstico y evolución según el tratamiento recibido. Métodos: Estudio retrospectivo donde se estudiaron 28 pacientes (23 mujeres/5 varones) con HP, edad promedio de 38±11.1 años. Resultados. Los síntomas fueron: cefalea: 68%, poliuria- polidipsia: 50% y alteraciones visuales: 48%. El examen de laboratorio inicial informó disfunción adenohipofisaria en 71% de los pacientes, siendo el eje gonadal el más afectado. Los hallazgos radiológicos más frecuentes fueron: lesión simétrica:78.5%, aumento homogéneo post contraste: 78.5% y engrosamiento de tallo:70%. En 4/23 mujeres (17%) se relacionó con embarazos o puerperio La conducta inicial fue expectante (CE) en 14 pacientes, cirugía de resección/descompresión en 8 y tratamiento con inmunosupresores en 6. Quince pacientes tuvieron confirmación histológica, 9 resultaron hipofisitis linfocitaria, 5 hipofisitis por IgG4 y una xantomatosa. Trece fueron diagnosticados por criterios clínicos establecidos. El tamaño de la lesión disminuyó en 43% de pacientes con CE, 62.5% con cirugía y 50% con inmunosupresores. Los síntomas compresivos mejoraron en los 3 grupos, con escaso efecto sobre la función adenohipofisaria, sin resolución de la diabetes insípida. Discusión: En pacientes sin síntomas compresivos adoptamos CE. En aquellos pacientes sin certeza diagnóstica o con síntomas compresivos graves, se optó por cirugía transesfenoidal.

Concurrent IgG4-related hypophysitis and clinically nonfunctioning gonadotroph pituitary neuroendocrine tumor.

BACKGROUND: Some patients develop immunoglobulin G4 (IgG4)-related hypophysitis associated with systemic diseases. More than 30 cases of IgG4-related hypophysitis have been reported. However, biopsy has rarely been performed in these patients, and none have had an associated pituitary neuroendocrine tumor (PitNET). We present a case of concurrent IgG4-related hypophysitis and PitNET. CASE PRESENTATION: A 56-year-old Japanese man arrived at the hospital with visual impairment, bitemporal hemianopia, and right abducens nerve palsy. Magnetic resonance imaging revealed pituitary body and stalk swelling as well as a small poorly enhanced right anterior lobe mass. Laboratory and loading test results suggested hypopituitarism. Because IgG4 level was elevated, a systemic examination was performed; multiple nodules were found in both lung fields. The diagnosis was based on an endoscopic transnasal biopsy of the pituitary gland. A histopathological examination revealed a marked infiltration of plasma cells into the pituitary gland, which was strongly positive for IgG4. The histological features of the resected tumor were consistent with those of gonadotroph PitNET, which was immunohistochemically positive for follicle-stimulating hormone-ß and steroidogenic factor-1, and no plasma cell infiltration was observed. Based on the histopathological examination results, steroid therapy was initiated, which reduced pituitary gland size and serum IgG4 levels. DISCUSSION AND CONCLUSIONS: This is the first reported case of IgG4-related hypophysitis with PitNET. Although no pathological findings indicating a relationship between the two conditions were found, we were able to preoperatively differentiate multiple lesions via detailed diagnostic imaging.

IgG4-related hypophysitis: a retrospective cohort study.

PURPOSE: IgG4-related hypophysitis (IgG4-RH) is a rare chronic inflammatory condition of the pituitary gland. This study reports the presentation, management and outcomes for patients with histologically proven IgG4-related hypophysitis. METHODS: A prospectively maintained electronic database was searched over a 14-year period from 1 January 2007 to 31 December 2020 at a single academic centre to identify all patients with a histological diagnosis of IgG4-RH. A retrospective case note review from electronic health records was conducted for each case to extract data on their presentation, management and outcomes. RESULTS: A total of 8 patients (5 male) with a median age of 51 years were identified. The most common presenting symptoms were headache (4/8; 50%), fatigue (3/8; 37.5%) and visual impairment (2/8; 25%). Three patients were initially treated with high-dose steroids aiming for reduction of the pituitary mass. However, ultimately all patients underwent transsphenoidal surgery. Post-operative changes included radiological reduction in pituitary mass in all patients that had imaging (7/7; 100%), improvement in vision (1/2; 50%), residual thick pituitary stalk (5/7; 71.4%), persistent anterior hypopituitarism (4/8; 50%) and panhypopopituitarism including diabetes insipidus (3/8; 37.5%). CONCLUSIONS: IgG4-RH is an increasingly recognised entity presenting with a variety of symptoms and signs. Clinical presentation is similar to other forms of hypophysitis. It is therefore important to consider IgG4-RH as a differential and to have a low threshold for pituitary biopsy, the diagnostic gold standard. The diagnosis of IgG4-RH will guide decisions for additional workup for IgG4-related disease, multi-disciplinary team involvement and follow-up.

An autopsy case study of lymphocytic hypophysitis induced by nivolumab treatment for esophageal malignant melanoma.

Immune checkpoint inhibitors such as anti-cytotoxic T-lymphocyte antigen-4 and anti-programmed death-1 antibodies are effective against malignant tumors. However, they induce unique adverse events known as immune-related adverse events. Hypophysitis is one of the most frequent immune-related adverse events of anti-cytotoxic T-lymphocyte antigen-4 therapies. However, there have been few reports describing the pathological findings of hypophysitis induced by anti-programmed death-1 antibodies. The present case is the first autopsy case of hypophysitis induced by nivolumab monotherapy, an anti-programmed death-1 antibody. Pathologically, lymphocytes infiltrated the anterior lobe of the pituitary gland, and the number of pituitary cells, especially adrenocorticotropic hormone-positive cells, decreased. However, necrosis and remarkable fibrosis were not observed. Immunohistologically, some pituitary cells expressed programmed death-ligand 1. Lymphocytes were predominantly CD8-positive T cells, and CD68-positive macrophages and CD20-positive B-cells were also observed. IgG and C4d were deposited on pituitary cells, but IgG4 (a subclass of nivolumab) was not detected. These findings indicate that type IVc and type II hypersensitivity mechanisms may occur in hypophysitis induced by anti-programmed death-1 antibodies and that the inflammatory mechanisms underlying hypophysitis induced by anti-programmed death-1 and anti-cytotoxic T-lymphocyte antigen-4 antibodies are different.

Recent insights into the pathogenesis of autoimmune hypophysitis.

INTRODUCTION: Hypophysitis is an inflammation of the pituitary gland and a rare case of hypopituitarism. Despite the expanding spectrum of histological variants and causative agents, its pathogenesis is far to be fully understood. The present review is focused on recent evidence concerning the pathogenesis of autoimmune hypophysitis by searching through online databases like MEDLINE and Scopus up to May 2021. AREAS COVERED: Hypophysitis frequently develops in the context of a strong autoimmune background, including a wide spectrum of subtypes ranging from the commonest form of lymphocytic hypophysitis to the newly described and less common IgG4-, anti-PIT-1, and ICI-induced forms. A peculiar combination of genetic predisposition, pituitary damage and immunological setting represents the pathogenetic basis of autoimmune hypophysitis, which is characterized by diffuse infiltration of the gland by lymphocytes and variable degrees of fibrosis followed by pituitary cell destruction. Anti-pituitary antibodies (APA) have been described in sera from patients suffering from autoimmune hypophysitis, though their pathophysiological significance remains largely unknown and their diagnostic value limited. EXPERT OPINION: In recent years hypophysitis has gained interest due to the increased number of new diagnoses and the recognition of novel subtypes. Further studies could lead to improvements in biochemical/immunological diagnosis and targeted treatments.

Th17 Cells Contribute to the Pathology of Autoimmune Hypophysitis.

Autoimmune hypophysitis is classified as primary if its origin is idiopathic and secondary if it develops as a consequence of treatment with immune checkpoint inhibitors. Expanding use of immunotherapy has been paralleled by the increasing hypophysitis prevalence. However, understanding of the immune responses driving the disease remains limited. Using a mouse model of primary hypophysitis, we have identified CD4+ T lymphocytes to be the main pituitary-infiltrating immune cell population. Functional analysis showed that they display a Th17 and Th1/Th17 phenotype. To examine involvement of proinflammatory Th1, Th17, and Th1/17 subsets in hypophysitis, we have isolated RNA from the formalin-fixed paraffin-embedded pituitary specimens from 16 hypophysitis patients (three of whom had hypophysitis secondary to immune checkpoint inhibitors), 10 patients with adenoma, and 23 normal pituitaries obtained at autopsy. Transcript levels of IFN-γ, IL-17A, IL-4, IL-10, TGF-ß, CD4, CD8α, and class II MHC transactivator were analyzed by the reverse transcription-quantitative PCR (RT-qPCR). Pituitary glands of patients with hypophysitis showed significantly higher IL-17A, CD4, and class II MHC transactivator mRNA levels compared with adenoma and normal pituitaries. All three secondary hypophysitis patients showed detectable IL-17A levels, but other cytokines were not detected in their pituitaries. Levels of IFN-γ, IL-4, IL-10, and TGF-ß did not differ between the groups. TGF-ß transcript was found in significantly fewer hypophysitis pituitaries (2 out of 16) compared with adenoma (7 out of 10) and normal pituitaries (11 out of 23). Presence of TGF-ß in two hypophysitis patients was associated with significantly lower IL-17A mRNA levels compared with hypophysitis patients with no detectable TGF-ß (p = 0.03).

IgG4-related hypophysitis in adolescence.

OBJECTIVES: IgG4-related hypophysitis is a novel clinical disease entity, which is typically seen in the sixth decade of life and is typically complicated by hypopituitarism. We describe an adolescent female with IgG4-related hypophysitis with normal pituitary function and summarize the relevant literature. CASE PRESENTATION: A 11.8-year-old girl presented with headache and left VI cranial nerve palsy. MRI brain identified an enlarged pituitary gland. Endocrine investigations revealed normal pituitary function. She underwent a transsphenoidal biopsy of the pituitary gland, and histological examination confirmed the diagnosis of IgG4-related hypophysitis. Serum IgG4 concentrations were normal and no evidence of other organ involvement was found. Although the patient tested strongly positive for TB on an interferon gamma release assay, pituitary biopsy was negative for granuloma formation and acid-fast bacilli (Ziehl-Neelson staining). IgG4-related hypophysitis was treated with oral prednisolone and mycophenolate-mofetil with a good response. CONCLUSIONS: We describe to the best of our knowledge, the youngest patient in the published literature with IgG4-related hypophysitis presenting without pituitary insufficiency. A literature review identified only five cases of IgG4-related hypophysitis in adolescence. Serum IgG4 concentrations were normal in all, except one of the adolescent patients reported so far, and appear unhelpful in diagnosis in this age group.

Histopathological findings in the landscape of IgG4-related pathology in patients with pituitary dysfunction: Review of six cases.

IgG4-related hypophysitis (IgG4-RH) is increasingly being reported as an isolated entity or, less frequently, as a manifestation of a multiorgan IgG4-related disease (IgG4-RD), in which typical histopathology is a cornerstone for the diagnosis. We aimed to describe the histopathological changes in the surgical specimens from patients with clinical signs of pituitary disease that fulfilled the current diagnostic criteria for IgG4-RH. Histopathological features were correlated with clinical and radiological findings. Of 19 patients with pituitary dysfunction and inflammatory changes in the surgical pituitary specimen operated on during 2011-2019, we identified five patients with typical IgG4-related pathology (lymphoplasmacytic infiltration with more than 10 IgG4-positive plasma cells per one high power microscopic field, representing at least 40% of all plasma cells and at least focal storiform fibrosis). One patient with diabetes insipidus and pachymeningitis with IgG4-related changes in a biopsy from the dura was also included. Additional histopathological changes that typically are not part of the IgG4-RH were observed: Rathke's cleft cyst in four and granulomatous changes in two patients. One patient had an elevated serum IgG4 level and systemic manifestations that could be associated with the systemic IgG4-RD. Our findings indicate that pure IgG4-RH is uncommon. All patients with pituitary dysfunction, beyond typical IgG4-related pathology, had other pathological findings that could trigger the secondary IgG4-response. Both primary pathology and secondary IgG4-related features should be reported in patients with pituitary dysfunction because their co-occurrence may cause atypical clinical and imaging features, and unexpected response to surgical and pharmacological treatment. The current criteria for the diagnosis of IgG4-RH can lead to overdiagnosis of IgG4-RH if additional pathological changes are not taken into consideration. The classification criteria of IgG4-RD proposed by the American College of Rheumatology/European League Against Rheumatism could help classify patients more properly as IgG4-RH if applied to the pituitary gland.

Autoimmune Hypophysitis With Systemic Lupus Erythematosus: A Case Report and Literature Review.

Background: Autoimmune hypophysitis (AH) is a primary autoimmune inflammatory disorder of the pituitary gland, which usually presents as a mass in the sella turcica. Systemic lupus erythematosus (SLE) is another inflammatory disorder in which the immune system attacks healthy cells and tissues throughout the body. Although both diseases are autoimmune disorders, they rarely coexist, and the relationship between them is unclear. Case Report: A 66-year-old man was evaluated at the endocrinology clinic because of worsening fatigue, anorexia, drowsiness, and leg oedema. Examination revealed alertness impairment and lower limb oedema. Laboratory tests showed anterior pituitary hypofunction. The treatment approach, with glucocorticoids and immunosuppressive agents, resulted in long-term remission of symptoms of hypopituitarism and hyponatraemia. Conclusions: Our case demonstrates a potential association between AH and SLE. AH may need to be considered in the evaluation of SLE patients with headache, hyperprolactinemia, a pituitary mass, and hypopituitarism.

Role of 18F-fluorodeoxyglucose (FDG) and 18F-2-fluorodeoxy sorbitol (FDS) in autoimmune hypophysitis: a case report.

BACKGROUND: Autoimmune hypophysitis is a rare disease characterized by the infiltration of lymphocytic cells into the pituitary gland. 18F-fluorodeoxyglucose (FDG) and 18F-2-fluorodeoxy sorbitol (FDS) positron emission tomography (PET) are well-established and emerging techniques, respectively, which may aid in the diagnosis and classification of autoimmune hypophysitis. CASE PRESENTATION: Here, we report a 40-year-old female diagnosed with central diabetes insipidus and multiple pituitary hormone deficiencies, and MRI revealed homogeneous signals in the pituitary gland as well as thickened in the pituitary stalk. FDG PET localized the pituitary and pituitary stalk lesions and displayed an SUVmax of 5.5. FDS, a sensitive radiotracer for bacterial infections but remains unproven under aseptic inflammation, also demonstrated elevated radioactivity, with an SUVmax of 1.1 at 30 min and 0.73 at 120 min. Transnasal biopsy suggested a diagnosis of autoimmune hypophysitis, and the patient displayed radiological and clinical improvement after treatment with glucocorticoids and hormone replacement. CONCLUSIONS: Autoimmune hypophysitis can display elevated FDG uptake, which aids in the localization of the lesions. In addition to revealing bacterial infection specifically, FDS can also accumulate under autoimmune conditions, suggesting that it could serve as a potential radiotracer for both bacterial and aseptic inflammation. TRIAL REGISTRATION: The patient was enrolled in study NCT02450942 (clinicaltrials.gov, Registered May 21, 2015).

IgG4 hypophysitis - a rare and underdiagnosed cause of pituitary gland and stalk mass-like thickening.

Our aim is to present a typical case of IgG4-related hypophysitis, which will offer insight into the aetiology and pathogenesis of this relatively newly described disease. IgG4 Related Disease is a protean systemic condition that mimics inflammatory, infectious, and malignant processes. Biopsy of affected organs will show a typical histopathological pattern.

Isolated Langerhans cell histiocytosis in the hypothalamic-pituitary region: a case report.

BACKGROUND: Langerhans cell histiocytosis (LCH) is a rare disease that mainly affects children, but this disease is significantly rarer in patients who are older than 15 years. In this disease, any organ can be involved. The skeleton, skin and lung are commonly affected, and isolated hypothalamic-pituitary (HP) involvement is relatively rare. Here we report a 17-year-old adolescent with isolated HP-LCH of enlarged pituitary stalk presented with central diabetes insipidus (CDI). CASE PRESENTATION: A 17-year-old male adolescent with polydipsia and polyuria accompanied with elevated serum sodium level and low urine osmolality for 3 weeks was referred to our hospital. After admission, hormonal evaluation showed that his growth hormone (GH) was slightly elevated, and serum osmolality and glucose were normal. The fluid deprivation-vasopressin test demonstrated CDI. Imaging examination showed an obvious thickening of the pituitary stalk. Lymphocytic hypophysitis, sarcoidosis and granulation tissue lesions were suspected. After oral 1-deamino-8-Darginine vasopressin (DDAVP) and prednisone were administered for 2 months, symptoms were relieved, and he discontinued taking the drugs by himself. On reexamination, imaging revealed changes in the size and shape of the pituitary stalk, with thickened nodules. Then, a diagnostic biopsy of the pituitary stalk lesion was performed. Immunohistochemistry confirmed the definitive diagnosis of LCH. The clinical symptoms subsided with oral hormone replacements. CONCLUSION: CDI is a rare symptom in children and adolescents. Most of the causes are idiopathic, while others are caused by central nervous system (CNS) disorders. Meanwhile, lymphocytic hypophysitis, germinoma, LCH and other CNS disorders can all present as thickening of the pituitary stalk, diffuse enlargement of the pituitary gland, and weakening of high signal intensity in the neurohypophysis on magnetic resonance imaging (MRI). The differential diagnosis among these diseases depends on immunohistochemistry evidence.

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.

Hipofisitis autoinmune: a propósito de un caso / Autoinmune hipophysitis. About a case

Se presentó un paciente negro, masculino, de 15 años de edad, con obesidad desde los 5 años, acantosis nigricans severa en cuello, axilas, manos, muslos, estrías anacaradas en brazos y abdomen. Ligera ptosis palpebral bilateral, dificultad visual ligera. Poliuria y polidipsia. Desproporción de la brazada en relación con la talla. Hipogenitalismo, para el diagnóstico de esta afección se aplicó el método clínico, las técnicas de imágenes evidenciaron una gran masa selar que comprometía el hipotálamo y la hipófisis. Se realizaron los estudios hormonales demostrándose un hipopituitarismo total, el diagnóstico definitivo se realizó mediante la biopsia estereotaxica donde se diagnóstica hipofisitis linfocitaria(AU)

A black male patient, 15 years of age, with obesity from the age of 5 year, severe acanthosis nigricans in neck,armpits, hands, thigs, stretch marks inarms and abdomen. Slight bilateral palpebral ptosis, slight visual difficulty. Polyuria and polydipsia. Disproportion of the stroke in relation to the size. Hypogenitalism, for the diagnosis of this condition. The clinical method was applied, the imaging techniques showed a large sellar mass that compromisedthe hypothalamus and pituitary gland. The hormonal studies were performed demostrating a total hypopituitarism, the definitive diagnosis was carried out by stereotactic biopsy where lymphocyte hypophysitis was diagnosed(EU)

Disease heterogeneity in IgG4-related hypophysitis: report of two histopathologically proven cases and review of the literature.

IgG4-related hypophysitis (IgG4-RH) is a rare disease, which can occur singularly or as manifestation of a systemic IgG4-related disease (IgG4-RD). Less than one hundred cases have been reported in the literature, very few of which were histopathologically documented. We analyzed the clinical, radiological, and histopathological features of two cases of IgG4-RH, the former observed in a 66-year-old man in the context of an IgG4-RD, and the latter affecting a 21-year-old woman, as an isolated lesion. In addition, we performed a comprehensive review of the previously published histopathologically documented cases of IgG4-RH. Pituitary samples from both patients showed dense lymphoplasmacytic infiltration, interstitial and storiform fibrosis, and high numbers of IgG4-positive plasma cells, consistent with IgG4-RH. From the literature review, we retrieved 18 papers reporting a total of 22 cases of histopathologically documented IgG4-RH. The revision of these cases, also including the two reported herein, showed an equal distribution of IgG4-RH in the two sexes, albeit significant clinico-pathological variation was found between cases arisen in female and male patients, respectively. In detail, IgG4-RH females were affected in their second-third decade of life, with a solitary pituitary lesion, low IgG4 serum level, and frequent association with autoimmune disorders. By contrast, IgG4-RH in men was a disease of the elderly, often in the context of a systemic IgG4-RD, with high IgG4 serum levels. Our study shows that IgG4-RH, as currently defined, is a clinically heterogenous disease, with different features in the two sexes. Indeed, cases diagnosed in young women, as our case 2, mostly do not present other evidence of IgG4-RD and might be better classified as lymphocytic hypophysitis with abundant IgG4+ plasma cells. For this reason, the histopathological examination of the pituitary lesion, particularly in female patients, may still be useful for a correct differential diagnosis with other variants of primary hypophysitis.

Clinical Features, Magnetic Resonance Imaging, and Treatment Experience of 20 Patients with Lymphocytic Hypophysitis in a Single Center.

OBJECTIVE: Lymphocytic hypophysitis (LYH) is a rare autoimmune inflammatory disease of the pituitary gland. In this study, we aim to characterize LYH at presentation and focus on the management and prognosis of LYH. METHODS: A retrospective study of patients with LYH was conducted between 2011 and 2018 at a single institute. The patients were included by pathologic conformation and strict exclusion criteria. Clinical profile, imaging, and management data were collected. RESULTS: Twenty patients with LYH (16 women and 4 men) were included. Ten patients were diagnosed histologically and the remaining 10 patients were confirmed clinically of exclusion criteria. The median age at diagnosis was 37 years (range, 16-58 years). Presenting symptoms were followed by polyuria/polydipsia (11, 55%), vision changes (10, 50%), headache (8, 40%), menstrual irregularities and amenorrhea (4, 20%), diplopia (1, 5%), or sexual dysfunction (1, 5%). Eight patients had partial anterior pituitary hormone dysfunction. The thyroid-stimulating hormone axis was most involved. Ten patients received transsphenoidal surgery, 5 patients experienced steroid pulse therapy, and observation was performed on 5 patients. Only 5 patients (25%) showed improvement of anterior pituitary dysfunction after initial management. Recovery of diabetes insipidus occurred in 2 patients (18%). The overall recurrence rate was 22.2%. CONCLUSIONS: Nonoperative treatment is a better option for most patients with LYH because it is effective and noninvasive. Surgery is recommended for definitive diagnosis, severe or rapid progression of neurologic impairment, and glucocorticoid insensitivity. Periodic follow-up is mandatory in a patient's long-term management.

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.

A case series of atypical features of patients with biopsy-proven isolated IgG4-related hypophysitis and normal serum IgG4 levels.

BACKGROUND: IgG4-related hypophysitis is a rare clinical entity that forms part of an emerging group of multi-organ IgG4-related fibrosclerotic systemic diseases. The rare prevalence of the disease, presenting features that overlap with other sellar pathologies, and variable imaging features can make preoperative identification challenging. PURPOSE AND METHODS: We report three cases of isolated IgG4-related hypophysitis with atypical clinical and imaging features that mimicked those of pituitary apoplexy and other sellar lesions. Additionally, we review the literature of IgG4-related hypophysitis to provide context for individual patient data described herein. RESULTS: All patients presented with symptoms that mimicked those of pituitary apoplexy and visual disturbance, and MRI findings suggestive of pituitary macroadenoma, Rathke's cleft cyst and craniopharyngioma. The clinical presentation warranted surgical decompression, resulting in rapid symptomatic improvement. Preoperative high-dose followed by postoperative low-dose glucocorticoid replacement therapy was administered in all cases. Histopathology showed dense infiltrate of IgG4 cells. Post-operative follow-up monitoring for 12-26 months revealed normal serum IgG4 levels with no other organ involvement, while endocrinological testing revealed persistent pituitary hormone deficiencies. CONCLUSIONS: Our cases highlight the importance of considering IgG4-related hypophysitis in the differential diagnosis of solid and cystic sellar lesions presenting acutely with pituitary apoplexy symptoms. Existing diagnostic criteria may not be sufficiently precise to permit rapid and reliable identification, or avoidance of surgery in the acute setting. In contrast to other reports of the natural history of this condition, despite the severity of presenting features, the disease in our cases was pituitary-restricted with normal serum IgG4 levels.