Clinical case seminar: lymphocytic hypophysitis: clinicopathological findings

[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.

Complete and Uneventful Recovery in a Case of Lymphocytic Hypophysitis Causing a Third Nerve Palsy

Lymphocytic hypophysitis (LH) is a neuroendocrine disorder characterised by autoimmune inflammation of the pituitary gland with resultant pituitary dysfunction. Rarely, the presenting symptom can be diplopia due to irritation of the third, fourth, or sixth cranial nerves secondary to cavernous sinus involvement of the mass or increased intracranial pressure. We describe the case of a healthy, 20-year-old female with a pupillary sparing third nerve palsy, who was subsequently diagnosed with LH after an endoscopic transsphenoidal biopsy of the mass. She was treated with hormone replacement therapy and corticosteroids, resulting in full resolution of symptoms with no recurrence to date. To our knowledge, this is the first report of a third nerve palsy due to definitive biopsy proven LH. Despite its rarity, the unique presentation and favourable evolution of this case should aid clinicians in its timely recognition, appropriate workup, and treatment.

Central Diabetes Insipidus Due to IgG4-related Hypophysitis That Required over One Year to Reach the Final Diagnosis Due to Symptoms Being Masked by Sialadenitis

Pituitary inflammation due to IgG4-related disease is a rare condition and is sometimes accompanied by central diabetes insipidus. Central diabetes insipidus produces a strong thirst sensation, which may be difficult to distinguish when complicated by salivary insufficiency. A 45-year-old man was admitted to our department for a thorough examination of his thirst and polyuria. He had suddenly developed these symptoms more than one year earlier and visited an oral surgeon. Swelling of the left submandibular gland, right parotid gland, and cervical lymph nodes had been observed. Since his IgG4 level was relatively high at 792 mg/dL and a lip biopsy showed high plasmacytoid infiltration around the gland ducts, he had been diagnosed with IgG4-related disease. He had started taking 0.4 mg/kg/day of prednisolone, and his chief complaint temporarily improved. However, since the symptom recurred, he was referred to our institution. After admission, to examine the cause of his thirst and polyuria, we performed a water restriction test, vasopressin loading test, hypertonic saline loading test and pituitary magnetic resonance imaging. Based on the findings, we diagnosed him with central diabetes insipidus due to IgG4-related hypophysitis. We increased the dose of prednisolone to 0.6 mg/kg/day and started 10 μg/day of intranasal desmopressin. His symptoms were subsequently alleviated, and his serum IgG4 level finally normalized. We should remember that IgG4-related disease can be accompanied by hypophysitis and that central diabetes insipidus is brought about by IgG4-related hypophysitis. This case report should remind physicians of the fact that pituitary inflammation due to IgG4-related disease is very rare and can be masked by symptoms due to salivary gland inflammation, which can lead to pitfalls in the diagnosis in clinical practice.

Preoperative differentiation of hypophysitis and pituitary adenomas using a novel clinicoradiologic scoring system

PURPOSE

Hypophysitis can clinically and radiologically mimic other nonfunctioning masses of the sella turcica, complicating preoperative diagnosis. While sellar masses may be treated surgically, hypophysitis is often treated medically, so differentiating between them facilitates optimal management. The objective of our study was to develop a scoring system for the preoperative diagnosis of hypophysitis.

METHODS

A thorough literature review identified published hypophysitis cases, which were compared to a retrospective group of non-functioning pituitary adenomas (NFA) from our institution. A preoperative hypophysitis scoring system was developed and internally validated.

RESULTS

Fifty-six pathologically confirmed hypophysitis cases were identified in the literature. After excluding individual cases with missing values, 18 hypophysitis cases were compared to an age- and sex-matched control group of 56 NFAs. Diabetes insipidus (DI) (p < 0.001), infundibular thickening (p < 0.001), absence of cavernous sinus invasion (CSI) (p < 0.001), relation to pregnancy (p = 0.002), and absence of visual symptoms (p = 0.007) were significantly associated with hypophysitis. Stepwise logistic regression identified DI and infundibular thickening as positive predictors of hypophysitis. CSI and visual symptoms were negative predictors. A 6-point hypophysitis-risk scoring system was derived: + 2 for DI, + 2 for absence of CSI, + 1 for infundibular thickening, + 1 for absence of visual symptoms. Scores ≥ 3 supported a diagnosis of hypophysitis (AUC 0.96, sensitivity 100%, specificity 75%). The scoring system identified 100% of hypophysitis cases at our institution with an estimated 24.7% false-positive rate.

CONCLUSIONS

The proposed scoring system may aid preoperative diagnosis of hypophysitis, preventing unnecessary surgery in these patients.

Outcomes of Initial Management Strategies in Patients With Autoimmune Lymphocytic Hypophysitis: A Systematic Review and Meta-analysis

CONTEXT

Lymphocytic hypophysitis (LyHy) is characterized by inflammation of the pituitary and or neuroinfundibulum and is uncommon. Treatment options include observation, high-dose glucocorticoids (HD-GCs) or surgery. Optimal first-line management strategy, however, remains unknown.

OBJECTIVE

This work aimed to assess response to first-line treatment options (observation, HD-GCs, or surgery) of clinically relevant outcomes (symptomatic, hormonal, and radiographic improvement) among patients with LyHy.

METHODS

A systematic review was conducted in 6 databases through 2020. Meta-analysis was conducted when feasible using a random-effects model.

RESULTS

We included 33 studies reporting on 591 patients (423 women, 72%) with LyHy. Improvement/resolution of anterior pituitary dysfunction was highest when HD-GCs was first-line treatment. Surgery was associated with the greatest proportion of patients who had regression on imaging. Subgroup analysis comparing HD-GCs to observation showed the odds of anterior pituitary hormone recovery (OR 3.41; 95% CI, 1.68-6.94) or radiographic regression (OR 3.13; 95% CI, 1.54-6.36) were higher with HD-GCs, but so was the need for additional forms of treatment (OR 4.37; 95% CI, 1.70-11.22). No statistically significant difference was seen in recovery of diabetes insipidus (OR 0.9; 95% CI, 0.26-3.10). Certainty in these estimates was very low.

CONCLUSION

Observation and use of HD-GCs both are successful first-line management strategies in LyHy. Although use of HD-GCs was associated with increased recovery of anterior pituitary hormone deficit, it also was associated with greater likelihood of additional treatment after withdrawal. Optimal dosing and duration of HD-GCs remains unknown.

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.

Pituitary Stalk Thickening: Causes and Consequences. The Children's Memorial Health Institute Experience and Literature Review

BACKGROUND

Pituitary stalk thickening (PST) is a rare abnormality in the pediatric population. Its etiology is heterogeneous. The aim of the study was to identify important clinical, radiological and endocrinological manifestations of patients with PST and follow the course of the disease.

MATERIALS AND METHODS

It is a study conducted in 23 patients (13 boys) with PST with/without central diabetes insipidus (CDI) diagnosed between 1990 and 2020 at Children's Memorial Health Institute (CMHI) in Warsaw, Poland. We analyzed demographic data, clinical signs and symptoms, radiological findings, tumor markers, hormonal results, treatment protocols and outcomes.

RESULTS

The median age at the diagnosis of PST was 9.68 years (IQR: 7.21-12.33). The median time from the onset of the symptoms to the diagnosis was 2.17 years (IQR: 1.12-3.54). The most common initially reported manifestations were polydipsia, polyuria and nocturia (82.6%); most of the patients (56.5%) also presented decreased growth velocity. Hormonal evaluation at the onset of PST revealed: CDI (91.3%), growth hormone deficiency (GHD) (56.5%), hyperprolactinemia (39%), central hypothyroidism (34.8%), adrenal insufficiency (9%), precocious puberty (8.7%). The majority of the patients were diagnosed with germinoma (seventeen patients - 73.9%, one of them with teratoma and germinoma). Langerhans cell histiocytosis (LCH) was identified in three patients (multisystem LCH in two patients, and unifocal LCH in one patient). A single case of atypical teratoid rhabdoid tumor, suspected low-grade glioma (LGG) and lymphocytic infundibuloneurohypophysitis (LINH). The overall survival rate during the observational period was 87.0%.

CONCLUSIONS

The pituitary infundibulum presents a diagnostic imaging challenge because of its small size and protean spectrum of disease processes. Germinoma should be suspected in all children with PST, especially with CDI, even when neurological and ophthalmological symptoms are absent.

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

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

Clinical aspects of autoimmune hypothalamitis, a variant of autoimmune hypophysitis: Experience from one center

Objective

Autoimmune hypothalamitis (AHT) is a rare inflammatory disorder that involves the hypothalamus. It remains unclear whether autoimmune hypophysitis (AH) and AHT represent different diseases or different aspects of the same disease. Thus, further investigation of AHT is required.

Methods

A retrospective review of medical and pathological records of AHT patients from the Chinese PLA General Hospital were examined from January 1, 2005 to May 1, 2017. Clinical data, treatments, and outcomes were investigated.

Results

Five female patients were identified (median age, 42.6 years). Symptoms included central diabetes insipidus, hypopituitarism, hyperprolactinemia, headache, and hypothalamic syndrome. The following hormonal deficits were noted: follicle-stimulating hormone, luteinizing hormone, adrenocorticotropic hormone, thyroid stimulating hormone, and growth hormone. One patient underwent high-dose methylprednisolone pulse treatment (HDMPT) and azathioprine plus intensity modulated radiation therapy (IMRT), and two patients underwent HDMPT and two rounds of replacement therapy. During follow-up, one patient died because of non-compliance with therapy and the others were in remission or they recovered.

Conclusions

AHT had similar MRI results, pathology, and treatment compared with AH. Thus, it may be a subtype of AH, and AHT patients may also show hypothalamic syndrome.

Prednisolone-responsive Postpartum IgG4-related Hypophysitis

We herein report the case of a 25-year-old woman who presented with severe headache and visual field defects after childbirth. Magnetic resonance imaging revealed marked swelling of the pituitary gland, and an endocrinological examination revealed panhypopituitarism and diabetes insipidus. An immunohistological analysis of a transsphenoidal biopsy sample of the pituitary gland showed the significant accumulation of an immunogloblin G4 (IgG4)-positive population, leading to the diagnosis of IgG4-related hypophysitis. The patient was treated with prednisolone, which markedly reduced the swelling of the pituitary gland, in association with recovery of the pituitary function. This is a rare case of biopsy-proven IgG4-related hypophysitis with a postpartum onset.

Imaging spectrum of immunomodulating, chemotherapeutic and radiation therapy-related intracranial effects

OBJECTIVE

A wide range of treatment-related side effects result in specific neurologic symptoms and signs and neuroimaging features. Even to the most seasoned neuroradiologist, elucidating therapy-related side effects from other common mimics can be challenging. We provide a pictorial survey of some common and uncommon medication-induced and therapy-related neuroimaging manifestations, discuss pathophysiology and common pitfalls in imaging and diagnosis.

METHODS

A case-based review is utilized to depict scenarios on a routine basis in a general radiology or neuroradiology practice such as medication-induced posterior reversible encephalopathy syndrome to the more challenging cases of pseudoprogression and pseudoregression in temozolmide and bevacizumab therapy in gliobastoma treatment protocols.

CONCLUSION

Knowledge of the treatment-induced imaging abnormalities is essential in the accurate interpretation and diagnosis from the most routine to most challenging of clinical situations. We provide a pictorial review for the radiologist to employ in order to be an invaluable provider to our clinical colleagues and patients.

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.

[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.

Pituitary Microsomal Autoantibodies in Patients with Childhood-Onset Combined Pituitary Hormone Deficiency: an Antigen Identification Attempt

The role of autoimmunization in the pathogenesis of pituitary disorders is poorly understood. The presence of pituitary autoantibodies (APA) has been detected in various pituitary disorders. Their role, however, remains elusive. Childhood-onset combined pituitary hormone deficiency (CPHD) may be caused by environmental or genetic factors. In some of patients, causes of the disease remain unclear and contributions of autoimmune processes have been postulated. The aim of this study was to identify the microsomes-derived pituitary antigens (MPA) as potential immunogenic autoantigens in patients with hypopituitarism, therefore 62 CPHD patients, 100 healthy controls and five autoimmune polyglandular syndrome type II (APS II) patients were included in the study. The clinical evaluation included hormonal tests and magnetic resonance imaging of the pituitary. The sources of MPA were pituitary glands taken from autopsies. Isolated MPA were then separated on SDS-PAGE gel and incubated with sera obtained from patients and controls. Microsomal APA were detected using Western blot and radioimmunological method. In all CPHD and APS II patients and in 9 % individuals from control group marked immunoreactivity was detected against MPA. Antibodies showed high affinity to 67, 60, 50 and 36 kDa MPAs. Since the identified autoantigens were of unknown nature, an in silico exploration of UniProt database was applied and indicated their possible relationship with chaperones, golgins and already known autoantigens like GAD67. Reactivity against MPA indicates that these proteins certainly play a role in the processes undergoing within pituitary of CPHD patients. The identification and further detailed studies on their role in the pathogenesis of CPHD should be continued.

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.

Pituitary macroadenoma with persisting dense lymphocytic infiltration in a young male patient

Context: Lymphocytic anterior hypophysitis in association with a pituitary adenoma was reported previously. In rare instance, inflammatory infiltration was confined to adenoma tissue itself, excluding anterior pituitary. Case: The patient – a 27-year-old male – presented with visual field defect. Further examination revealed a pituitary mass with suprasellar extension. Hormonal evaluation indicated mild hyperprolactinemia (42 ng/ml, normal < 19). After transsphenoidal resection, a pituitary adenoma showing cytoplasmic immunoreactivity to prolactin was identified. Dense and diffuse lymphocytic infiltration was seen within the tumor. At 15th month, a second transsphenoidal operation was necessary because of rapid development of visual compromise and headache. Excised surgical specimen consistent with previously resected adenoma showed diffuse lymphocytic infiltration composed of B and T cells within the adenoma tissue again. Conclusion: Presence of dense, hypophysitis-like lymphocytic infiltration within pituitary adenoma tissue obtained by two consecutive operations may reflect an host-mediated immune reaction to tumor. This rare finding could be challenging in terms of differential diagnosis and follow-up course.

Sheehan's syndrome: new insights into an old disease

Sheehan's syndrome (SS) is a parturition-related pituitary disease resulting from severe postpartum hemorrhage and can present with varying degrees of pituitary insufficiency. Pathological and clinical findings of SS were first described by Harold L. Sheehan in the previous century. Although his definitions are still valid, various studies and reports including new data have subsequently been published. Additionally, the diagnosis of SS has often been overlooked and thus delayed for long years due to its nonspecific signs and symptoms. Therefore, a large number of patients may be remained undiagnosed and untreated. SS is not as rare as assumed in developed countries, probably due to migrant women and unawareness of physicians regarding the syndrome. In this review, we provide a detailed review of the epidemiology, etiopathogenesis, clinical, laboratory and radiological features, new diagnostic criteria, differential diagnosis, and treatment of SS.

Primary central nervous system vasculitis preceded by granulomatous hypophysitis: Case report with a review of the literature

BACKGROUND

Primary central nervous system (CNS) vasculitis is an idiopathic inflammatory process that selectively affects CNS vasculature without a systemic inflammatory response, and causes luminal obstruction with resultant ischemia of recipient tissue. Its varying clinical symptoms and signs depend on the caliber of vessels involved and distribution and location of the affected structures. Granulomatous hypophysitis (GH) is an autoimmune inflammatory process typically affecting women, and usually presents with hypopituitarism, and at times, diabetes insipidus, and/or visual loss. Both entities are rare CNS diseases, which, to our knowledge, have never been previously reported in the same patient.

CASE DESCRIPTION

We present a unique case of chronic progressive primary CNS vasculitis causing limbic encephalopathy in a 30-year-old male with only a history of medication-controlled hypertension. He initially presented 4 months prior with nonspecific neurological complaints and was found to have a homogenously enhancing and enlarged pituitary, which was biopsy proven to be GH.

CONCLUSION

This rather unique presentation highlights the need to maintain a high index of suspicion for underlying PCNS vasculitis in a patient who does not fit the typical demographic for isolated GH.

An unexpected headache: pituitary apoplexy in a pregnant woman on anticoagulation

Pituitary apoplexy is a rare event in which the pituitary gland undergoes infarction or haemorrhage, most commonly in the setting of an underlying tumour. We report on apoplexy of an undiagnosed pituitary adenoma precipitated both by physiological enlargement of the pituitary in pregnancy and prophylactic anticoagulation from a history of deep vein thrombosis. The haemorrhage was managed conservatively without significant complications.

Neuroendocrine causes of amenorrhea--an update

CONTEXT

Secondary amenorrhea--the absence of menses for three consecutive cycles--affects approximately 3-4% of reproductive age women, and infertility--the failure to conceive after 12 months of regular intercourse--affects approximately 6-10%. Neuroendocrine causes of amenorrhea and infertility, including functional hypothalamic amenorrhea and hyperprolactinemia, constitute a majority of these cases.

OBJECTIVE

In this review, we discuss the physiologic, pathologic, and iatrogenic causes of amenorrhea and infertility arising from perturbations in the hypothalamic-pituitary-adrenal axis, including potential genetic causes. We focus extensively on the hormonal mechanisms involved in disrupting the hypothalamic-pituitary-ovarian axis.

CONCLUSIONS

A thorough understanding of the neuroendocrine causes of amenorrhea and infertility is critical for properly assessing patients presenting with these complaints. Prompt evaluation and treatment are essential to prevent loss of bone mass due to hypoestrogenemia and/or to achieve the time-sensitive treatment goal of conception.

Prolactin may be increased in newly diagnosed celiac children and adolescents and decreases after 6 months of gluten-free diet

BACKGROUND/AIMS

Prolactin (PRL) is produced by the anterior pituitary gland. It exerts its role on the breast gland but also plays a modulatory role in autoimmune mechanisms. Celiac disease (CD) is a gluten-sensitive autoimmune enteropathy sometimes associated with autoimmune endocrinopathies. No data on PRL levels in CD patients are available at diagnosis, and no conclusive data are reported.

METHODS

We aimed to evaluate PRL secretion in newly diagnosed CD pediatric patients and, in the case of hyperprolactinemia, any changes in its levels while the patients were on a gluten-free diet (GFD). We recruited 67 patients and 39 healthy controls.

RESULTS

PRL was statistically higher in the CD patients (13.5±9.2 ng/ml) than in the controls (8.5±5.0 ng/ml). In the CD group, PRL was inversely correlated with the age at diagnosis (r=-0.326; p=0.007). In patients with hyperprolactinemia at diagnosis, PRL decreased after 6 months of GFD.

CONCLUSION

This paper confirms that PRL may be increased at diagnosis of CD and shows, for the first time, that it decreases after a short course of GFD. Changes in the levels of inflammatory cytokines in CD may account for changes in PRL levels. Younger patients seem more prone to develop hyperprolactinemia than older ones.

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.

Ipilimumab and its toxicities: a multidisciplinary approach

The treatment for metastatic melanoma has evolved significantly in the past few years. Ipilimumab, an immunotherapy, is now in mainstream oncology practice given that it has shown improved overall survival in randomized clinical trials. Other immune modulating agents, such as programmed death receptor-1 and programmed death receptor ligand-1 antibodies, are showing promise in early clinical trials. This manuscript will review ipilimumab and its most common side effects. Immune-related adverse events (irAEs) are important to recognize early, and their presentation, timing of onset, and general recommendations for workup and management will be reviewed. Assembling a multidisciplinary team, as well as thorough education of the patient, is recommended to optimize patient care.

[Hypophysitis: increasingly complex clinicopathological spectrum!]

Hypophysitis is a chronic inflammation of the pituitary gland that comprises an increasingly complex clinicopathological spectrum. Lymphocytic and granulomatous hypophysitis are the most common forms, but new variants have recently been reported such as IgG4-related hypophysitis that is identified by well-defined criteria. For the first time, hypophysitis in ANCA-associated vasculitides has been reported. Monoclonal antibodies directed against the cytotoxic T-lymphocyte antigen-4 (CTLA-4), investigated in metastatic melanoma, can induce hypophysitis. Hypophysitis's pathogenesis remains obscure but several candidate pituitary autoantigens have been described in the last decade, although none has proven useful as a diagnostic tool.

Hypophysitis induced by monoclonal antibodies to cytotoxic T lymphocyte antigen 4: challenges from a new cause of a rare disease

Specific human monoclonal antibodies antagonize cytotoxic T-lymphocyte antigen 4 (anti-CTLA-4 mAbs), a negative regulator of the immune system, inducing unrestrained T-cell activation. In patients with advanced or metastatic melanoma, one of these agents, ipilimumab, produced considerable disease control rates and, for the first time, a clear improvement in overall survival outcomes. However, accumulating clinical experience with anti-CTLA-4 mAbs identified a novel syndrome of autoimmune and autoinflammatory side effects, designated as "immune-related adverse events," including mainly rash, colitis, and hepatitis. Autoimmune hypophysitis has emerged as a distinctive side effect induced by anti-CTLA-4 mAbs. This condition may be life threatening because of adrenal insufficiency if not promptly recognized, but it may easily be diagnosed and treated if clinically suspected. Hypopituitarism caused by these agents is rarely reversible and prolonged or life-long substitutive hormonal treatment is often required. The precise mechanism of injury to the pituitary triggered by anti-CTLA-4 mAbs is yet to be fully elucidated.

Identification of TPIT and other novel autoantigens in lymphocytic hypophysitis: immunoscreening of a pituitary cDNA library and development of immunoprecipitation assays

BACKGROUND

Lymphocytic hypophysitis is an organ-specific autoimmune disease of the pituitary gland. A specific and sensitive serological test currently does not exist to aid in the diagnosis.

OBJECTIVE

To identify target autoantigens in lymphocytic hypophysitis and develop a diagnostic assay for these proteins.

DESIGN/METHODS

A pituitary cDNA expression library was immunoscreened using sera from four patients with lymphocytic hypophysitis. Relevant cDNA clones from screening, along with previously identified autoantigens pituitary gland-specific factor 1a and 2 (PGSF1a and PGSF2) and neuron-specific enolase (NSE) were tested in an in vitro transcription and translation immunoprecipitation assay. The corticotroph-specific transcription factor, TPIT, was investigated separately as a candidate autoantigen.

RESULTS

Significantly positive autoantibody reactivity against TPIT was found in 9/86 hypophysitis patients vs 1/90 controls (P = 0.018). The reactivity against TPIT was not specific for lymphocytic hypophysitis with autoantibodies detectable in the sera from patients with other autoimmune endocrine diseases. Autoantibodies were also detected against chromodomain-helicase-DNA binding protein 8, presynaptic cytomatrix protein (piccolo), Ca(2+)-dependent secretion activator, PGSF2 and NSE in serum samples from patients with lymphocytic hypophysitis, but at a frequency that did not differ from healthy controls. Importantly, 8/86 patients with lymphocytic hypophysitis had autoantibodies against any two autoantigens in comparison with 0/90 controls (P = 0.0093).

CONCLUSIONS

TPIT, a corticotroph-specific transcription factor, was identified as a target autoantigen in 10.5% of patients with lymphocytic hypophysitis. Further autoantigens related to vesicle processing were also identified as potential autoantigens with different immunoreactivity patterns in patients and controls.

Diagnosis and treatment of autoimmune hypophysitis: a short review

Medical therapy of autoimmune hypophysitis with immunosuppressive drugs can be effective to induce remission of the disease by treating both pituitary dysfunction and compression symptoms. We describe the case of a 41-yr-old man with autoimmune hypophysitis in whom prednisone therapy induced remission of the disease but was followed by a sudden relapse after withdrawal. A second trial of corticosteroid was started and succeeded in inducing remission of the disease. Eight months after the second withdrawal pituitary function was restored, pituitary mass had disappeared, only partial diabetes insipidus remained unchanged. Review of the literature identified 30 articles, among case reports and case series, reporting a total of 44 cases of autoimmune hypophysitis treated with glucocorticoids and/or azathioprine. Combining all the cases, medical therapy resulted to be effective in reducing the pituitary mass in 84%, in improving anterior pituitary function in 45%, and in restoring posterior pituitary function in 41%. Clinical aspects of autoimmune hypophysitis are discussed and a possible algorithm for the diagnosis and treatment of the disease is proposed.

Pituitary stem cell update and potential implications for treating hypopituitarism

Stem cells have been identified in organs with both low and high cell turnover rates. They are characterized by the expression of key marker genes for undifferentiated cells, the ability to self-renew, and the ability to regenerate tissue after cell loss. Several recent reports present evidence for the presence of pituitary stem cells. Here we offer a critical review of the field and suggest additional studies that could resolve points of debate. Recent reports have relied on different markers, including SOX2, nestin, GFRa2, and SCA1, to identify pituitary stem cells and progenitors. Future studies will be needed to resolve the relationships between cells expressing these markers. Members of the Sox family of transcription factors are likely involved in the earliest steps of pituitary stem cell proliferation and the earliest transitions to differentiation. The transcription factor PROP1 and the NOTCH signaling pathway may regulate the transition to differentiation. Identification of the stem cell niche is an important step in understanding organ development. The niche may be the marginal zone around the lumen of Rathke's pouch, between the anterior and intermediate lobes of mouse pituitary, because cells in this region apparently give birth to all six pituitary hormone cell lineages. Stem cells have been shown to play a role in recurrent malignancies in some tissues, and their role in pituitary hyperplasia, pituitary adenomas, and tumors is an important area for future investigation. From a therapeutic viewpoint, the ability to cultivate and grow stem cells in a pituitary predifferentiation state might also be helpful for the long-term treatment of pituitary deficiencies.

Adenohypophysitis in rat pituitary allografts

The histological, immunohistochemical and ultrastructural alterations in 81 pituitary allografts from Lewis rats transplanted beneath the renal capsule of Wistar rats were investigated. Intrasellar pituitaries of rats bearing allografts were also examined. Recipient rats were sacrificed at various time points after transplantation. Two days after transplantation, the central portion of the allografts demonstrated ischaemic necrosis. A week later, massive mononuclear cell infiltrates consisting primarily of lymphocytes and to a lesser extent, macrophages, plasma cells and granulocytes became prominent. At about three to four weeks after transplantation, the mononuclear cell infiltrate diminished; the surviving adenohypophysial cells, mainly prolactin (PRL) cells, increased in number and necrosis was replaced by connective tissue. No histological changes were noted in the intrasellar pituitaries of rats bearing allografts. Immunohistochemistry demonstrated that the surviving adenohypophysial cells were mainly PRL-producing cells. Electron microscopy revealed adenohypophysial cell destruction, a spectrum of inflammatory cells and, in late phase, accumulation of fibroblasts and collagen fibres. PRL cells were the prominent cell types; they increased in number. It appears that pituitary allografts are 'foreign' and evoke an immune response, suggesting that they may be used as an experimental animal model for morphological investigation of the development and progression of adenohypophysitis, a rare disease occurring mainly in young women often associated with pregnancy.

Alopecia universalis, hypothyroidism and pituitary hyperplasia: polyglandular autoimmune syndrome III in a patient in remission from treated Hodgkin lymphoma

We herein report a case of a 33-year-old man in remission from Hodgkin lymphoma, who presented with reduced potency and hair loss. Initial endocrine tests revealed autoimmune hypothyroidism. An MRI of his pituitary gland at onset revealed hyperplasia. He tolerated replacement endocrine therapy with good response, but with no improvement in his alopecia universalis. A repeat MRI, 6 months after his initial endocrine manipulation, showed resolution of his pituitary hyperplasia.

The long-term clinical follow-up and natural history of men with adult-onset idiopathic hypogonadotropic hypogonadism

CONTEXT AND OBJECTIVE

Adult-onset idiopathic hypogonadotropic hypogonadism (AHH) is a rare disorder characterized by an isolated failure of gonadotropin secretion occurring after an otherwise normal sexual maturation in men. This study aims to examine the etiology and long-term natural history of this disorder.

DESIGN AND SETTING

Long-term follow up, including detailed clinical, biochemical, and genetic examinations, were performed and compared with those at diagnosis.

PATIENTS

Patients included 10 men with AHH [serum testosterone (T) <125 ng/dl].

INTERVENTIONS

Overnight neuroendocrine studies, semen fluid analyses, and genetic screening were performed (KAL1, FGFR1, PROK2, PROKR2, NELF, TAC3, TACR3, and GNRH1) over a decade of longitudinal follow up.

RESULTS

Follow-up evaluations were conducted 10.6 +/- 5.9 yr after initial studies and revealed that the clinical characteristics and seminal fluid analyses of AHH men (body mass index, 28.8 +/- 4.1 vs. 27.0 +/- 4.3 kg/m(2); testicular volume, 18 +/- 6 vs. 19 +/- 6 ml) do not change over a decade with no spontaneous reversals. Several men exhibited some variability in their endogenous GnRH-induced LH secretory patterns, including emergence of endogenous pulsatility in three individuals. However, all remained hypogonadal (T < or =130 ng/dl). A single heterozygous DNA sequence change in PROKR2 (V317L) was identified, although this rare sequence variant did not prove to be functionally abnormal in vitro. Seven days of pulsatile GnRH therapy in this subject nearly normalized his serum T, supporting that the site of the defect is hypothalamic and not pituitary.

CONCLUSIONS

1) AHH in men appears to be a long-lasting condition. 2) Although minor changes in the abnormal pattern of endogenous GnRH-induced LH secretion occurred in some AHH patients, all remained frankly hypogonadal.

Parasellar T2 dark sign on MR imaging in patients with lymphocytic hypophysitis

BACKGROUND AND PURPOSE

MR imaging findings of LYH and pituitary adenomas are similar, but the therapeutic strategies are completely different. The purpose of this study was to evaluate sellar and parasellar MR imaging findings in patients with both diseases, as well as characteristic clinical findings.

MATERIALS AND METHODS

Clinical findings, including endocrinologic study and MR images of 20 patients with LYH and 22 patients with pituitary adenoma, were retrospectively reviewed. We evaluated the MR images in relation to the following: 1) the PPHI on T1-weighted images, 2) thickened stalk (>3.5 mm), 3) pituitary symmetry, 4) pituitary enhancement pattern, 5) a dural tail, and 6) parasellar signal intensity on T2- and T1-weighted images.

RESULTS

Between patients with LYH and those with pituitary adenoma, a significant difference was identified for the number of patients with loss of PPHI, thickened stalk, pituitary symmetry, homogeneous enhancement, and parasellar dark signal intensity on T2-weighted images by statistical analysis (Fisher exact probability test, P < .05). Among them, only parasellar dark signal intensity on T2-weighted images had no false-positive cases.

CONCLUSIONS

The parasellar T2 dark sign can be a specific finding used to distinguish pituitary adenoma from LYH.

A case of apoplectic lymphocytic hypophysitis complicated by polymyalgia rheumatica

A case of apoplectic lymphocytic hypophysitis complicated by polymyalgia rheumatica (PMA) is described. A 72-year-old man was admitted to our hospital due to severe headache. Two months prior to admission, the patients had exhibited recent-onset stiffness and myalgia of shoulder and pelvic girdle that was compatible with PMR. Magnetic resonance imaging revealed a mass lesion in the pituitary fossa with focal hemorrhage. Endocrinologic studies demonstrated hypopituitarism. The headache and myalgia were improving with corticosteroid treatment; however, a trans-sphenoidal surgery was performed due to visual field loss. A white-colored mass was resected, and histologic examination showed diffuse infiltration of lymphocytes and plasma cells consistent with lymphocytic hypophysitis. Post-operatively, the headache and visual field loss resolved completely. This is the first documented case of apoplectic lymphocytic hypophysitis complicating PMR, and a possible mechanism for this rare association was discussed.

Collision sellar lesions: experience with eight cases and review of the literature

The concomitant presence of a pituitary adenoma with a second sellar lesion in patients operated upon for pituitary adenoma is an uncommon entity. Although rare, quite a great variety of lesions have been indentified coexisting with pituitary adenomas. In fact, most combinations have been described before, but an overview with information on the frequency of combined pathologies in a large series has not been published. We present a series of eight collision sellar lesions indentified among 548 transsphenoidally resected pituitary adenomas in two Neurosurgical Departments. The histological studies confirmed a case of sarcoidosis within a non-functioning pituitary adenoma, a case of intrasellar schwannoma coexisting with growth hormone (GH) secreting adenoma, two Rathke's cleft cysts combined with pituitary adenomas, three gangliocytomas associated with GH-secreting adenomas, and a case of a double pituitary adenoma. The pertinent literature is discussed with emphasis on pathogenetic theories of dual sellar lesions. Although there is no direct evidence to confirm the pathogenetic relationship of collision sellar lesions, the number of cases presented in literature makes the theory of an incidental occurrence rather doubtful. Suggested hypotheses about a common embryonic origin or a potential interaction between pituitary adenomas and the immune system are presented.

[A 36-year old female patient presenting with hypoglycemic coma]

A 36-year-old female was admitted to the emergency department with a hypoglycemic shock of unknown origin. Initial diagnostic procedures could exclude diabetes mellitus, postprandial hypoglycemia, insulinoma, tumor, drug side effects, and exogenous insulin application. Detailed evaluation of the patient's history revealed that the patient had not been able to lactate after an uncomplicated pregnancy and delivery 3 years ago. Endocrinological evaluation showed a complete adrenocorticotropic insufficiency caused by a Sheehan syndrome. Concomitantly, an empty sella syndrome was visible in MRI. Even after an uncomplicated delivery and even with normal laboratory values, Sheehan-Syndrome can become manifest in a hypoglycemic shock due to hypopituitarism with insufficiency of the adrenocorticotropic axis.

Lymphocytic hypophysitis with associated thyroiditis in a man with aseptic meningitis

OBJECTIVE

Lymphocytic hypophysitis (LH) is a rare chronic inflammatory disorder characterized by lymphocytic infiltration of the pituitary gland commonly affecting women during pregnancy or post-partum period. The pathogenesis remains uncertain, however an autoimmune process is frequently implicated. There is limited data on the occurrence of LH outside the setting of autoimmunity.

CASE

We describe a 37-year-old man presenting with diarrhoea, nausea, weight loss, low-grade fever, headache and cerebrospinal fluid analysis consistent with aseptic meningitis. Magnetic resonance imaging (MRI) demonstrated a homogenously enlarged pituitary gland with biochemical testing revealing partial hypopituitarism with adenocorticotrophic hormone and gonadotrophin deficiency. Notably, his free thyroid hormone levels were elevated with a suppressed thyroid-stimulating hormone and a suppressed thyroid technetium scan consistent with thyroiditis. Tissue antibodies including thyroid antibodies were negative. Following introduction of hydrocortisone, he developed transient diabetes insipidus which spontaneously resolved after 4 months. Thyrotoxicosis resolved after 5 weeks and thyroxine was commenced as he developed secondary hypothyroidism. Repeat MRI 3 months later showed a reduction in the size of the pituitary gland which by 6 months had returned to normal size. He remains well on hydrocortisone, thyroxine and testosterone replacement.

CONCLUSIONS

Based on clinical and radiological grounds, the diagnosis was consistent with lymphocytic hypophysitis associated with subacute thyroiditis. This is only the second report of this combination in the absence of autoimmunity and the first report of LH and thyroiditis with associated aseptic meningitis in the absence of tissue autoantibodies. We propose a possible viral illness as the unifying aetiological cause.

Lymphocytic hypophysitis in the pediatric population

BACKGROUND

Lymphocytic hypophysitis (LYH) is a rare inflammatory disease of the pituitary gland that usually affects women in their ante- or immediate postpartum period; males are affected less frequently than females. An autoimmune pathogenesis is suggested. Symptoms comprise anterior and/or posterior pituitary insufficiency of varying degrees. So far, specific characteristics of this rare disease in childhood are not well described.

CASE HISTORY

We report the case of a 12-year-and-11-month-old boy with histologically confirmed LYH clinically presenting with diabetes insipidus. A high-dose steroid therapy was administered, in which the therapeutic effect was uncertain. His 6-year follow-up is presented.

DISCUSSION

The literature is reviewed for children presenting with LYH; their characteristics, pituitary involvement, and clinical follow-up are listed and discussed.

CONCLUSION

Even though magnetic resonance imaging can be highly suspicious for LYH, only surgical exploration can confirm the diagnosis. The efficacy of medical treatment is still controversial; a close follow-up is necessary to control and correct the endocrinological function, if required.

Hypophysitis superimposed on a non-functioning pituitary adenoma: diagnostic clinical, endocrine, and radiologic features

Pituitary adenomas are common neoplasms requiring medical and/or surgical treatment when associated with hormonal hypersecretion. Treatment of non-functioning pituitary adenomas is necessary when symptoms of mass effect or hormonal deficits occur. However, therapeutic options, including surgical resection and/or radiotherapy, can be associated with significant complications. Hence, it is important to consider disorders that could present in a similar manner to pituitary adenomas, for which surgery is not the indicated therapeutic approach. We describe herein a 38-yr-old woman who presented with a pituitary lesion that was considered to be a non-functioning pituitary adenoma. Due to lack of hormonal deficits and/or compression of adjacent structures, we opted for conservative management and followup with consecutive magnetic resonance imaging. Fifteen months after initial diagnosis, considerable enlargement of the lesion was noted, extending mainly superiorly and indenting the optic chiasm. Repeated endocrine investigation revealed partial anterior pituitary insufficiency. The patient underwent trans-sphenoidal resection of the pituitary lesion; histology revealed a null cell pituitary adenoma and lymphocytic hypophysitis (LYH) of the non-neoplastic adenohypophysial gland. Post-operatively, complete anterior and partial posterior pituitary insufficiency developed. This case illustrates the effects of new-onset LYH in a patient with a pre-existing non-functioning pituitary adenoma. Being aware of this rare possibility is important, as enlargement of the pituitary lesion may not be caused by expansion of the preexisting tumor, but by the onset of LYH of the nonneoplastic pituitary tissue.

Lymphocytic panhypophysitis in a young man with involvement of the cavernous sinus and clivus

Lymphocytic hypophysitis is an unusual inflammatory lesion that is caused by autoimmune destruction of the pituitary gland. We report a case of 42-year-old man who presented with a 6-month history of severe headache, blurred vision in the right eye, hearing loss, polyuria, polydipsia, and impotence. Medical history showed that he and his mother had osteopetrosis. The results of the physical examination and laboratory tests showed that secondary hypothyroidism, hypogonadism, and hypocortisolism had developed. Central diabetes insipidus was diagnosed by water deprivation test. MRI of the sella showed pituitary enlargement with symmetrical suprasellar expansion, compression of the chiasma, thickened infundibulum, and involvement of both bilateral cavernous sinuses and clivus. Hormonal substitution with hydrocortisone, levothyroxine, and DDAVP resulted in rapid improvement of all symptoms and signs. Transsphenoidal biopsy was diagnostic of lymphocytic hypophysitis. In spite of extensive literature reviewing, we have not been aware of any case of lymphocytic hypophysitis with clivus involvement. The present case represents a variant of lymphocytic hypophysitis which has progressed to involve bilateral cavernous sinuses and the clivus.

Aetiology, diagnosis, and management of hypopituitarism in adult life

Hypopituitarism is a complex medical condition associated with increased morbidity and mortality, requires complicated treatment regimens, and necessitates lifelong follow up by the endocrinologist. The causes, clinical features, and the management of hypopituitarism including endocrine replacement therapy are considered in this review article.

Cytotoxic T-lymphocyte-associated antigen-4 blockage can induce autoimmune hypophysitis in patients with metastatic melanoma and renal cancer

Cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) is an immunoregulatory molecule expressed by activated T cells and resting CD4CD25 T cells. In patients with advanced melanoma, our group reported that administration of anti-CTLA-4 antibody mediated objective cancer regression in 13% of patients. This study also established that the blockade of CTLA-4 was associated with grade III/IV autoimmune manifestations that included dermatitis, enterocolitis, hepatitis, uveitis, and a single case of hypophysitis. Since this initial report, 7 additional patients with anti-CTLA-4 antibody-induced autoimmune hypophysitis have been accumulated. The characteristics, clinical course, laboratory values, radiographic findings, and treatment of these 8 patients are the focus of this report.

Lymphocytic hypophysitis: disease spectrum and approach to diagnosis and therapy

Lymphocytic hypophysitis (LYH) is a neuroendocrine disorder characterized by autoimmune inflammation of the pituitary gland with various degrees of pituitary dysfunction. The histopathology consists of an initial monoclonal lymphocytic infiltrate, which can heal with minimal sequela or progress to fibrosis and result in permanent hypopituitarism. Coexistence of other autoimmune conditions is reported in 25-50% of cases and pituitary autoantibodies have been detected in up to 70% of biopsy-proven cases. The clinical presentation varies depending on the pituitary segment that is more severely affected. In lymphocytic adenohypophysitis (LAH) an early destruction of the ACTH-producing cells is characteristic. Other anterior pituitary hormones can also be affected but posterior pituitary involvement is absent or minimum. Lymphocytic Infundibuloneurohypophysitis (LINH) typically presents as acute onset diabetes insipidus (DI) with intracranial mass-effect symptoms. A combination of extensive anterior pituitary involvement and DI characterizes lymphocytic Infudibulopanhypophysitis (LIPH). The diagnosis can be challenging in many cases, because distinction from pituitary adenomas and other sellar masses is not obvious. Significant efforts have been made to identify specific serum markers, but it would seem unlikely that this approach will ever have the specificity to replace histopathological examination of a surgical specimen. Diagnostic criteria have been proposed to help in the decision-making process and to avoid, whenever possible, unnecessary invasive procedures. The therapeutic approach is controversial and, although transsphenoidal surgery is often performed, a conservative medical management is justified in many cases, given the self-limited nature of the inflammatory process. This paper reviews the etiology, epidemiology, clinical and radiological findings, diagnosis and management of LYH.

Prolactin and autoimmunity

The interrelationship between prolactin (PRL) and the immune system have been elucitaded in the last decade, opening new important horizons in the field of the immunoendocrinology. PRL is secreted not only by anterior pituitary gland but also by many extrapituitary sites including the immune cells. The endocrine/paracrine PRL has been shown to stimulate the immune cells by binding to PRL receptors. Increased PRL levels, frequently described in autoimmune diseases, could depend on the enhancement of coordinated bi-directional communications between PRL and the immune system observed in these diseases. Hyperprolactinemia has been described in the active phase of some non organ-specific autoimmune diseases, as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) and organ-specific autoimmune diseases, as celiac disease, type 1 diabetes mellitus, Addison's disease, autoimmune thyroid diseases. In these diseases PRL increases the syntesis of IFNgamma and IL-2 by Th1 lymphocytes. Moreover, PRL activates Th2 lymphocytes with autoantibody production. Of particular interest is the association between hyperprolactinemia and levels of anti DNA antibodies, islet cell antibodies (ICA), thyreoglobulin antibodies (TgAb), thyroperoxidase antibodies (TPOAb), adrenocortical antibodies (ACA), transglutaminase antibodies (tTGAb) in SLE, in type 1 diabetes mellitus, in Hashimoto's thyroiditis, in Addison's disease and in celiac disease, respectively. High levels of PRL have been also frequently detected in patients with lymphocytic hypophysitis (LYH). Several mechanisms have been invoked to explain the hyperprolactinemia in LYH. The PRL increase could be secondary to the inflammatory process of the pituitary gland but, on the other hand, this increase could have a role in enhancing the activity of the immune process in LYH. Moreover, the detection of antipituitary antibodies targeting PRL-secreting cells in some patients with idiopathic hyperprolactinemia suggests the occurrence of a possible silent LYH in these patients. Finally, the role of anti-prolactinemic drugs to inactivate the immune process in LYH is still discussed.

Lymphocytic hypophysitis with diabetes insipidus: improvement by methylprednisolone pulse therapy

Lymphocytic hypophysitis is a rare inflammatory disorder in the pituitary gland. The lesion is usually confined to the adenohypophysis. Although the involvement of the posterior pituitary gland or the stalk is rare, such patients with diabetes insipidus have been reported. Surgery has been used to make the definitive diagnosis. Recent studies suggest, however, that the pathologic diagnosis may not be necessary always. We reported a case of Lymphocytic hypophysitis managed by methylprednisolone pulse therapy. A 50-year-old premenopausal woman with Lymphocytic hypophysitis and diabetes insipidus was treated with methylprednisolone pulse therapy. Her adenopituitary lesion disappeared and the diabetes insipidus resolved. The optimal management for patients with lymphocytic hypophysitis may be the high index of the suspicion prior to the extensive surgical resection. In addition, methylprednisolone pulse therapy may improve the clinical and MRI findings.

A relapsing remitting lymphocytic hypophysitis

Lymphocytic Hypophysitis is a rare autoimmune disease of the pituitary presenting mainly with features of a mass lesion and loss of pituitary function. Its course is quite unpredictable and its treatment is still controversial as experience in the field remains scarce. We describe a 45 year-old woman with a history of recurrent fever and meningeal symptoms who was referred 3 years later to our department for pituitary insufficiency. Hormonal studies revealed an anterior pituitary deficiency and autoimmune thyroiditis. Pituitary hypertrophy as evidenced by magnetic resonance imaging showed complete regression upon hydrocortisone substitution therapy. Two years later, fever and meningeal symptoms recurred as well as pituitary hypertrophy. Cerebrospinal fluid analysis revealed an aseptic lymphocytic meningitis. Pituitary biopsy confirmed the diagnosis of LH. The patient was started on prednisone 70 mg per day. She improved clinically and radiologically and remained free of symptoms thereafter. At a recent follow up the MRI showed an empty sella turcica. Hereby we illustrate a yet unreported pattern of LH presenting as a recurrent aseptic meningitis. We also describe one of the long-term course of the disease which is still unpredictable.

Lymphocytic hypophysitis: report of an unusual case of a rare disorder

A 36-year-old non-pregnant woman presented with a four-month history of progressive visual deterioration and amenorrhea. The latest gestation was 6 years earlier. Hormonal study revealed central diabetes insipidus, hypopituitarism, and slightly increased prolactin level. Ophthalmologic examination showed bilateral hemianopsia. In the magnetic resonance imaging an intrasellar mass with supra and retrosellar extension was found. The mass showed a polylobular aspect with heterogeneous signal within the tissue. The normal neurohypophysis could not be identified. Pterional craniotomy was performed. The pathological examinations revealed fibrous tissue with heavy inflammatory infiltrate composed of lymphocytes and plasma cells, islands of eosinophilic epithelial cells stained positively for chromogranin, GH, ACTH, and PRL and negatively for antibodies directed against HLA-II antigens. This case of lymphocytic hypophysitis was not related to pregnancy and involved the neurohypophysis. We discuss the features that can help to make a preoperative differential diagnosis.