Cases: Decompensated Heart Failure Secondary to Hypopituitarism in an Elderly Patient.

Hypopituitarism is difficult to diagnose because of its non-specific symptoms, especially in the presence of comorbidities. A 77-year-old woman with worsening anorexia and exertional dyspnea was initially diagnosed with decompensated dry cold-type heart failure. Hormonal laboratory tests indicated secondary hypothyroidism as a part of the evaluation of heart failure. Furthermore, pituitary magnetic resonance imaging revealed thickening of the pituitary stalk and a loss of signal intensity in the posterior pituitary, thus suggesting lymphocytic hypophysitis. Oral hydrocortisone and levothyroxine improved the persistent anorexia. In this case, hypopituitarism occasionally presented as dry cold-type heart failure, thus making a prompt diagnosis challenging in the setting of concurrent heart failure.

Unique case of lymphocytic hypophysitis with normal pituitary hormone serology mimicking a non-functioning pituitary adenoma.

BACKGROUND: Lymphocytic hypophysitis is a rare autoimmune condition that usually presents during pregnancy and causes inflammation of the pituitary gland. Although the pathophysiology is not well understood, it often presents with headaches, visual disturbances, and symptoms of hypopituitarism. However, not all cases may present with hypopituitarism which can make this rare disease with an incidence of ~ 1 in 9 million much more difficult to diagnose. CASE PRESENTATION: We present a 35-year-old G4P4 woman with progressive vision loss and intermittent frontal headaches during her first trimester through 2 months postpartum. She presented with no symptoms of hypopituitarism and her hormone panel only showed elevated prolactin, possibly due to her breastfeeding. She was treated with a right pterional craniotomy with decompression of both optic nerves, partial resection of the suprasellar mass, and glucocorticoid therapy for headaches and visual disturbances. CONCLUSION: This case is notable for a presentation of lymphocytic hypophysitis without symptoms of hypopituitarism. This is important for outpatient providers to be aware of, especially those that care for pregnant patients so that unfavorable outcomes can be avoided.

Endoscopic endonasal transsphenoidal surgery for unusual sellar lesions: eight cases and review of the literature.

Background: Preoperative imaging for some unusual lesions in the sellar region can pose challenges in establishing a definitive diagnosis, impacting treatment strategies. Methods: This study is a retrospective analysis of eight cases involving unusual sellar region lesions, all treated with endoscopic endonasal transsphenoidal surgery (EETS). We present the clinical, endocrine, and radiological characteristics, along with the outcomes of these cases. Results: Among the eight cases, the lesions were identified as follows: Solitary fibrous tumor (SFT) in one case, Lymphocytic hypophysitis (LYH) in one case, Cavernous sinus hemangiomas (CSH) in one case, Ossifying fibroma (OF) in two cases; Sphenoid sinus mucocele (SSM) in one case, Pituitary abscess (PA) in two cases. All patients underwent successful EETS, and their diagnoses were confirmed through pathological examination. Postoperatively, all patients had uneventful recoveries without occurrences of diabetes insipidus or visual impairment. Conclusion: Our study retrospectively analyzed eight unusual lesions of the sellar region. Some lesions exhibit specific imaging characteristics and clinical details that can aid in preoperative diagnosis and inform treatment strategies for these unusual sellar diseases.

Successful treatment of medically and surgically refractory lymphocytic hypophysitis with fractionated stereotactic radiotherapy: a single-center experience and systematic literature review.

PURPOSE: To explore the potential role of focused radiotherapy in managing the lymphocytic hypophysitis (LH) refractory to medical therapy and surgery. METHOD: A systematic literature review was conducted following PRISMA guidelines to identify the studies on radiation treatment for hypophysitis, along with the experience in our institution. RESULTS: The study included eight patients, three from our institution and five from existing literature. The age at presentation ranged from 37 to 75 years old, with a median age of 58. The presenting symptoms involved headache in seven patients and diplopia in two patients. Pre-radiation visual field defects were noticed in four patients. All patients exhibited variable degrees of hypopituitarism before radiation, with oral corticosteroids being the initial medical treatment. Immunosuppressive therapy was attempted in two patients prior to radiation. Seven patients had a history of transsphenoidal surgery with a histologically confirmed LH. Three patients underwent stereotactic radiosurgery (SRS), while the remaining received FSRT, with a mean irradiation volume of 2.2 cm3. A single-session total dose of 12 -15 Gy was administered in the SRS group. In the FSRT group, doses ranged from 24 to 30 Gy with a median dose of 25 Gy, delivered in 2 Gy fractions. Four patients achieved a resolution of visual field defects, while another two patients demonstrated improvement in their associated focal neurologic deficits. No change in pre-existing endocrine status was shown after radiation, except in one patient. Clinical response was achieved in seven patients after a single course of radiation, while one patient required the second course. Six patients remained stable on low-dose glucocorticoid during at least a 12-month follow-up period, and one discontinued it entirely without experiencing relapse. Three patients demonstrated a complete radiologic response, while the remaining showed a partial radiologic response. CONCLUSIONS: Focused radiation, including FSRT, can play a role in symptomatic relief, effective mass shrinkage, and minimizing radiation exposure to critical surrounding structures in patients with refractory LH. However, further research efforts are necessary to better clarify its effects and optimal dose planning.

Coronavirus as a trigger of lymphocytic hypophysitis in an adolescent girl: An exceptional case report.

INTRODUCTION AND IMPORTANCE: Lymphocytic hypophysitis is an underestimated disease and the pathogenesis is still poorly elucidated. Post-coronavirus lymphocytic hypophysitis is a new emerging entity. CASE PRESENTATION: A 16-year-old previously healthy girl presented with pituitary tumor syndrome. She suffered from frontal headaches, polyuria-polydipsic syndrome, and impaired visual acuity. She was diagnosed with COVID-19 infection three weeks before. Contrast-enhanced magnetic resonance imaging (MRI) revealed pituitary enlargement with intense homogenous enhancement postgadolinium on T1 weighted images. The diagnosis of lymphocytic hypophysitis was made after ruling out other differential diagnosis. She was started on methylprednisolone. Improvement of clinical symptoms was seen on day 5 with a significant decrease in headache intensity. CLINICAL DISCUSSION: The article summarizes data from cases reported in the literature and our case to highlight coronavirus as a new trigger of lymphocytic hypophysitis. Despite the rarity of this complication, patients with a suspicion of hypophysitis after a recent COVID-19 infection should be carefully evaluated. CONCLUSION: COVID-19 infection can cause lymphocytic hypophysitis. However, it seems premature to conclude on the causal link between COVID-19 and endocrine diseases. Further studies on larger samples are needed to comprehend the pathogenesis of autoimmune endocrinopathies after COVID-19 infection.

A Case of Lymphocytic Infundibulo-neurohypophysitis Exhibiting Spontaneous Regression.

Lymphocytic infundibulo-neurohypophysitis (LINH) is a rare autoimmune inflammatory process that selectively affects the neurohypophysis and the pituitary stalk, typically presenting with central diabetes insipidus (CDI). LINH is considered underdiagnosed because the definitive diagnosis requires invasive pituitary surgery with a high risk of complications. We present a case of CDI resulting from LINH, which was treated with conservative management, eschewing both glucocorticoid treatment and pituitary surgery. At presentation, the hormonal assessment indicated the presence of CDI without anterior pituitary dysfunction. Magnetic resonance imaging revealed stalk thickening without a posterior pituitary bright spot, and anti-rabphilin-3A antibodies were positive in serum. Collectively, we made a diagnosis of LINH. Considering that the patient did not exhibit any symptoms of mass effect, we chose conservative treatment with desmopressin acetate. One year later, the stalk thickening regressed spontaneously without surgical or glucocorticoid treatment, although the posterior pituitary bright spot remained absent, and CDI did not improve. The inflammatory process of LINH is mostly self-limited and recovers spontaneously, whereas life-long desmopressin treatment may be required because of pituitary stalk fibrosis and atrophy. Our case highlights the importance of noninvasive diagnosis and careful follow-up in preventing unnecessary interventions for patients with LINH.

Recurrent Lymphocytic Hypophysitis Presenting as Internal Carotid Artery Stenosis and Oculomotor Nerve Palsy.

A 75-year-old woman presented with nausea and vomiting. Magnetic resonance imaging (MRI) revealed that she had a pituitary mass. A biopsy revealed lymphocytic hypophysitis (LYH). Symptoms were improved by hormone replacement therapy. Although she was asymptomatic, follow-up MRI revealed an increase in the size of the mass. Intravenous methylprednisolone (IVMP) reduced the size of the mass; however, right ophthalmalgia and oculomotor nerve palsy developed. MRI showed that the pituitary mass had enlarged to the right oculomotor nerve in the cavernous sinus and to the right internal carotid artery (ICA), causing stenosis of the ICA. After IVMP administration, the symptoms dramatically improved, but ICA stenosis persisted.

Lymphocytic Infundibuloneurohypophysitis Diagnosis Owing to Positive Anti-rabphilin-3A Antibody Test Result in an 8-year-old Boy with Early-onset Central Diabetes Insipidus.

Childhood-onset lymphocytic infundibuloneurohypophysitis (LINH) has rarely been reported. Pathological evaluation via pituitary biopsy is necessary for a definitive diagnosis of LINH. However, pituitary biopsy is a highly invasive procedure. Recently, anti-rabphilin-3A antibody (RPH3A-Ab) has been reported as a promising diagnostic marker for LINH in adults; however, there are few such reports in the pediatric population. We report the case of an 8-year-old boy with central diabetes insipidus (CDI) who was clinically diagnosed with LINH based on RPH3A-Ab positivity. He was diagnosed with CDI using a water deprivation test combined with desmopressin administration. Serum and cerebrospinal fluid tumor markers were negative, and T1-weighted magnetic resonance imaging (MRI) revealed the absence of high signal intensity in the posterior pituitary gland and an enlarged pituitary stalk. Anterior pituitary function tests revealed no abnormalities. No pituitary biopsy was performed because of its invasive nature, and desmopressin treatment was initiated. Three months after CDI onset, the patient tested positive for RPH3A-Ab. MRI performed 9 months after CDI onset revealed amelioration of the pituitary stalk enlargement, and the clinical course corroborated our diagnosis of LINH. RPH3A-Ab may be useful as an early diagnostic tool for LINH in the pediatric population.

Clinical presentation and magnetic resonance imaging characteristics of lymphocytic hypophysitis: a systematic review with meta-analysis.

Introduction: This meta-analysis was performed to analyze the clinical presentation, magnetic resonance imaging (MRI) characteristics, and the management of lymphocytic hypophysitis (LYH). Material and methods: Four different databases were searched from January 2010 to December 2020, two researchers independently conducted literature screening, data extraction, and quality evaluation. We used a random effects meta-analysis to calculate summary relative risks with 95% CI. Results: This meta-analysis showed that the percentage of women among LYH patients was 78%. LYH was associated with pregnancy in 15% of female patients, with headache (49%) and symptoms of central diabetes insipidus (CDI) (45%) being the most frequent presentation. In 24% of LYH patients, there was an association with another autoimmune disease. The incidence of secondary hypogonadism, secondary hypoadrenalism, secondary hypothyroidism, and growth hormone deficit was 54%, 49%, 43%, and 22%, respectively. Pituitary contrast enhancement (63%), symmetrical pituitary enlargement (60%), thickening of the pituitary stalk (58%), sella mass or suprasellar extension (58%), and loss of posterior pituitary hyperintensity (50%) were typical MRI findings. Regarding LYH treatment, the percentage of patients who had observation or hormone replacement, steroid therapy, and surgery was 43%, 36%, and 34%, respectively. Conclusions: It is of great significance to fully understand the clinical characteristics of lymphocytic hypophysitis, reduce missed diagnosis and misdiagnosis, avoid unnecessary surgery and maintain normal pituitary function.

Lymphocytic Panhypophysitis Mimicking Glaucoma: Case Report.

Lymphocytic hypophysitis (LH) is a primary inflammatory disorder of the pituitary gland and infundibulum that commonly manifests in both mass effect and endocrinologic symptoms. Although the exact pathophysiology remains unclear, it has been increasingly linked to an autoimmune process. Complications arise by two separate mechanisms. Inflammation in the sella can lead to headaches and visual field defects. Pituitary inflammation and, chronically, fibrosis interfere with the gland's hormone-secreting capacity, often resulting in various endocrinopathies such as polyuria, polydipsia, amenorrhea, and others. While final histologic classification requires pathologic evaluation, diagnosis can often be made clinically with appropriate imaging. Treatment often consists of conservative management but can also include glucocorticoids or surgical resection. We present a case of biopsy-proven LH involving the entire pituitary, dubbed lymphocytic panhypophysitis (LPH) that was misdiagnosed for years as glaucoma due to the lack of endocrinopathy as well as delay in magnetic resonance imaging. After imaging revealed the sellar mass, the patient responded symptomatically to surgical resection and glucocorticoid treatment. LPH may present without endocrinologic symptoms and therefore mimic alternate diagnoses such as glaucoma. Clinicians should be suspicious of a diagnosis of glaucoma in the setting of a temporal field defect and lack of response to traditional therapy. A personal or family history of autoimmune disease in such patients should prompt further imaging and investigation. Therefore, endocrinopathy is supportive but not present in every case of LPH.

Bilateral Optic Neuritis and Hypophysitis With Diabetes Insipidus 1 Month After COVID-19 mRNA Vaccine: Case Report and Literature Review.

Either optic neuritis (neuropathy) or hypopituitarism has been known to occur separately after COVID-19 vaccination. In this report, we describe the rare combination of hypophysitis and optic neuritis which occurred after COVID-19 vaccination. A 74-year-old woman began to have thirst, polydipsia, and polyuria, and was diagnosed as central diabetes insipidus 1 month after the fourth COVID-19 mRNA vaccine. Head magnetic resonance imaging (MRI) disclosed the thickened pituitary stalk and enlarged pituitary gland with high contrast enhancement as well as the absence of high-intensity signals in the posterior pituitary lobe on the T1-weighted image, leading to the diagnosis of lymphocytic hypophysitis. She was well with desmopressin nasal spray until further 2 months later, when she developed bilateral optic neuritis, together with gait disturbance, intention tremor of the upper extremities, urinary retention, constipation, abnormal sensation in the distal part of the lower extremities, and moderate hemiplegia on the left side. Autoantibodies, including anti-aquaporin 4 (AQP4) and anti-myelin oligodendrocyte glycoprotein (MOG), were all negative. She showed multifocal spinal cord lesions on MRI and oligoclonal bands in the cerebrospinal fluid obtained by spinal tap, and so underwent steroid pulse therapy with methylprednisolone in the tentative diagnosis of multiple sclerosis, resulting in visual acuity recovery and alleviation of neurological symptoms. In the literature review, the combination of optic neuritis and hypophysitis, mostly with diabetes insipidus, was reported in 15 patients as case reports before the years of COVID-19 pandemic. The COVID-19 vaccination would trigger the onset of hypophysitis and optic neuritis in this patient.

Characteristics of inflammatory and infectious diseases of the pituitary gland in patients undergoing transsphenoidal surgery.

PURPOSE: Inflammatory and infectious diseases of the pituitary gland (IIPD) are rare lesions often misdiagnosed preoperatively. Immediate surgery is indicated especially in cases of neurological impairment. However, (chronic) inflammatory processes can mimic other pituitary tumors, such as adenomas, and data on the preoperative diagnostic criteria for IIPD are sparse. METHODS: We retrospectively reviewed medical records of 1317 patients who underwent transsphenoidal surgery at our institution between March 2003 and January 2023. A total of 26 cases of histologically confirmed IIPD were identified. Patient records, laboratory parameters, and postoperative course were analyzed and compared with an age, sex, and tumor volume-matched control group of nonfunctioning pituitary adenomas. RESULTS: Pathology confirmed septic infection in ten cases, most commonly caused by bacteria (3/10) and fungi (2/10). In the aseptic group, lymphocytic hypophysitis (8/26) and granulomatous inflammation (3/26) were most frequently observed. Patients with IIPD commonly presented with endocrine and/or neurological dysfunction. No surgical mortality occurred. Preoperative radiographic findings (cystic/solid tumor mass, contrast enhancement) did not significantly differ between IIPD and adenomas. At follow-up, 13 patients required permanent hormone substitution. CONCLUSION: In conclusion, correct preoperative diagnosis of IIPD remains challenging, as neither radiographic findings nor preoperative laboratory workup unequivocally identify these lesions. Surgical treatment facilitates decompression of supra- and parasellar structures. Furthermore, this low-morbidity procedure enables the identification of pathogens or inflammatory diseases requiring targeted medical treatment, which is crucial for these patients. Establishing a correct diagnosis through surgery and histopathological confirmation thus remains of utmost importance.

Two children with lymphocytic hypophysitis presenting with positive anti-rabphilin-3A antibody.

Lymphocytic hypophysitis (LYH) is a rare chronic inflammatory disease characterized by lymphocytic infiltration of the anterior or posterior pituitary gland and hypothalamus. LYH is subdivided into lymphocytic adenohypophysitis (LAH), lymphocytic infundibulo-neurohypophysitis (LINH), and lymphocytic panhypophysitis (LPH) depending on the primary site. Most cases occur in adults, with few cases reported in children, and it is especially important to distinguish LYH from suprasellar malignancies, such as germ cell tumors and other neoplastic diseases. Although a biopsy is necessary for definitive diagnosis, it is desirable to be able to diagnose the disease without biopsy if possible, especially in children, because of the surgical invasiveness of the procedure. Recently, serum anti-rabphilin-3A antibodies have attracted attention as diagnostic markers for LYH, especially in LINH, but there are only a few reports on pediatric patients. In the present study, we experienced two children with LPH and LAH, respectively, who tested positive for anti-rabphilin-3A antibodies. This is the first report of children with LYH other than LINH positive for anti-rabphilin-3A antibodies, and anti-rabphilin-3A antibodies may be a useful non-invasive diagnostic marker not only for LINH but also for LYH in general. We also discuss the sensitivity and specificity of anti-rabphilin-3A antibody testing in cases where histological diagnosis has been made.

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.

Pregnancy-related hypophysitis revisited.

OBJECTIVE: The aim of the study is to assess the distinguishing features of pregnancy-related hypophysitis (PR-Hy) compared to non-pregnancy autoimmune hypophysitis and to evaluate the changing therapeutic approaches and outcomes in PR-Hy over time. DESIGN: Retrospective analysis of all published cases with PR-Hy and 6 own cases. METHODS: A PubMed search was performed and abstracts screened for publications with information on cases with PR-Hy from which full-text review was performed. Clinical features, diagnostic findings, and outcome in relation to treatment modalities in PR-Hy were assessed. RESULTS: One hundred and forty-eight cases with PR-Hy were identified. PR-Hy was significantly delimited from non-PR-Hy by the frequent occurrence of the chiasmal syndrome (50% vs 13%, P < .0001), higher rate of intrasellar origin (94% vs 74%, P = .0005), lower rate of pituitary stalk involvement (39% vs 86%, P < .0001), and low rate of diabetes insipidus (12% vs 54%, P < .0001). The role of surgery in PR-Hy decreased over time while noninvasive treatment modalities increased. The recurrence rate after high-dose glucocorticoid therapy (33%) was high and exceeded that of surgery (2%) and conservative management (2%). In contrast to initial reports on PR-Hy, recent literature regarding outcome of mother's and child's health was positive. The frequency of spontaneous preterm delivery was not increased. Recurrent PR-Hy in a subsequent pregnancy was reported in only two females. CONCLUSION: PR-Hy has distinct features that delineate the disorder from non-PR-Hy. With increasing experience in diagnosis, availability of adequate replacement therapy, and improved treatment modalities, PR-Hy has lost its threat and the outcome is encouraging.

Arterial spin labeling clinical applications for brain tumors and tumor treatment complications: A comprehensive case-based review.

Arterial spin labeling (ASL) is a noninvasive neuroimaging technique that allows for quantifying cerebral blood flow without intravenous contrast. Various neurovascular disorders and tumors have cerebral blood flow alterations. Identifying these perfusion changes through ASL can aid in the diagnosis, especially in entities with normal structural imaging. In addition, complications of tumor treatment and tumor progression can also be monitored using ASL. In this case-based review, we demonstrate the clinical applications of ASL in diagnosing and monitoring brain tumors and treatment complications.

Central diabetes insipidus with anti-rabphilin-3A antibody positivity causing hypovolemic shock after resection of tumorous lesions in the pelvic cavity.

A 36-year-old female was pointed out to have liver enzyme elevation by routine health checkup. Subsequent contrast-enhanced CT scan identified gigantic uterine fibroids and retroperitoneal tumor. She was referred to the gynecologist at JA Toride Medical Center and planned to undergo a uterus enucleation and biopsy of the retroperitoneal tumor. The surgery was conducted without any troubles. After the surgery, the patient presented polyuria with urine volume 10-20 L a day and developed hypovolemic shock. Laboratory test revealed hypotonic urine and hypernatremia. Arginine vasopressin (AVP) loading test suggested shortage of endogenous vasopressin. Since the subcutaneous administration of AVP was not sufficient to control the urine volume, continuous intravenous infusion of AVP was initiated. After achieving hemodynamic stability, the treatment was switched to oral desmopressin. MRI finding indicated attenuation of high signal in posterior pituitary in T1 weighted image while neither enlargement of pituitary nor thickening of pituitary stalk was indicated by enhanced MRI. Hypertonic salt solution test indicated no responsive elevation of AVP, confirming the diagnosis of central diabetes insipidus (CDI). Her anterior pituitary function was preserved. Only anti-rabphilin-3A antibody was found positive in the serum of the patient, while other secondary causes for CDI were denied serologically and radiologically. Hence, lymphocytic infundibuloneurohypophysitis　(LINH) was suspected as the final diagnosis. Hormonal replacement therapy by nasal desmopressin was continued and the patient managed to control her urine volume. In cases of CDI considered idiopathic with conventional examinations, anti-rabphilin-3A antibody may be a clue for determining the cause as LINH.

Lymphocytic Hypophysitis in a Patient With Suspected Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH).

Lymphocytic hypophysitis (LH) is a rare, autoimmune condition that presents with a range of symptoms that must garner the attention of medical practitioners. Clinically, it is characterized by symptoms of a compressive sellar mass with varying degrees of hypopituitarism due to chronic inflammatory infiltrate of the pituitary gland. It is often seen in women in their third trimester or postpartum and is associated with other autoimmune phenomena. Our case report describes a 73-year-old female with a past medical history of hypothyroidism and hypertension, who presented with continued intermittent dizziness, fatigue, and mild subjective hearing loss for the past several months. She was referred to the emergency department due to a sodium level of 119 and was initially diagnosed with syndrome of inappropriate antidiuretic hormone secretion (SIADH). The patient was treated accordingly; however, she failed to show signs of improvement. Due to her clinical presentation, imaging studies, and laboratory results, the patient was suspected to have LH, which was confirmed with the improvement of her symptoms after treatment with steroids. Because of the rare occurrence and possible atypical presentation of LH, this case illustrates the importance of maintaining a high index of clinical suspicion when diagnosing a patient with an unknown cause of hyponatremia, especially in patients with coexisting autoimmune disorders.

Secondary autoimmune hypothalamitis with severe memory impairment 7 years after the onset of diabetes insipidus due to lymphocytic hypophysitis: a case report.

BACKGROUND: Autoimmune hypothalamitis is a very rare neuroendocrine disorder that causes central diabetes insipidus, headache, visual impairment, and sometimes cognitive impairment. Autoimmune hypothalamitis may occur in association with autoimmune hypophysitis, including lymphocytic hypophysitis, or in isolation. It is not known whether autoimmune hypothalamitis and autoimmune hypophysitis are consecutive diseases. CASE PRESENTATION: A 52-year-old woman developed autoimmune hypothalamitis 7 years after developing central diabetes insipidus due to lymphocytic hypophysitis, resulting in severe memory impairment. High-dose intravenous methylprednisolone therapy improved her cognitive function and decreased the size of the lesion. CONCLUSION: This case presented a unique clinical course, with a long period of time between the onset of autoimmune hypopituitaritis and the development of autoimmune hypothalamitis.

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.