Re-analysis of gene mutations found in pituitary stalk interruption syndrome and a new hypothesis on the etiology.

Background: Pituitary stalk interruption syndrome (PSIS) is a complex clinical syndrome characterized by varied pituitary hormone deficiencies, leading to severe manifestations across multiple systems. These include lifelong infertility, short stature, mental retardation, and potentially life-threatening pituitary crises if not promptly diagnosed and treated. Despite extensive research, the precise pathogenesis of PSIS remains unclear. Currently, there are two proposed theories regarding the pathogenic mechanisms: the genetic defect theory and the perinatal injury theory. Methods: We systematically searched English databases (PubMed, Web of Science, Embase) and Chinese databases (CNKI, WanFang Med Online, Sinomed) up to February 24, 2023, to summarize studies on gene sequencing in PSIS patients. Enrichment analyses of reported mutated genes were subsequently performed using the Metascape platform. Results: Our study included 37 articles. KEGG enrichment analysis revealed mutated genes were enriched in the Notch signaling pathway, Wnt signaling pathway, and Hedgehog signaling pathway. GO enrichment analysis demonstrated mutated genes were enriched in biological processes such as embryonic development, brain development, axon development and guidance, and development of other organs. Conclusion: Based on our summary and analyses, we propose a new hypothesis: disruptions in normal embryonic development, partially stemming from the genetic background and/or specific gene mutations in individuals, may increase the likelihood of abnormal fetal deliveries, where different degrees of traction during delivery may lead to different levels of pituitary stalk interruption and posterior lobe ectopia. The clinical diversity observed in PSIS patients may result from a combination of genetic background, specific mutations, and variable degrees of traction during delivery.

[Effect of growth hormone supplementation on liver and lung function in patients with hypopituitarism].

To analyze the clinical features of patients with anterior hypopituitarism (HP) complicated with cirrhosis, and to explore the effects of growth hormone supplementation on liver and lung function. A total of 11 patients with HP complicated with cirrhosis admitted to Peking Union Medical College Hospital from January 2016 to December 2022 were included in the study, including 8 males and 3 females, aged [M(Q1, Q3)]31 (20, 37) years. There were 6 patients with pituitary stalk interruption syndrome, 4 patients after craniopharyngioma resection, and 1 patient after germinal cell tumor chemoradiotherapy. Cirrhosis appeared at [M(Q1, Q3)]7 (1, 16) years after the diagnosis of HP. There were 7 cases complicated with hepatopulmonary syndrome (HPS). The liver and lung function of 5 patients were improved significantly after the addition of growth hormone, and the arterial partial pressure of oxygen increased from (47±11) mmHg(1 mmHg=0.133 kPa) to (84±12) mmHg. Timely supplementation of growth hormone can improve the symptoms of fatty liver, cirrhosis and HPS, and postpone or even avoid the transplantation of liver and other organs.

Tocilizumab for the fifth progression of cystic childhood craniopharyngioma-a case report.

We present the case of a 15-year-old girl, with a fifth cystic progression of an adamantinomatous craniopharyngioma after multiple surgeries and previous local radiotherapy. She had severe visual impairment, panhypopituitarism including diabetes insipidus, and several components of hypothalamic damage, including morbid obesity and severe fatigue. To prevent further late effects hampering her quality of survival, she was treated biweekly with intravenous tocilizumab, an anti-interleukin-6 agent, which stabilized the cyst for a prolonged time. Based on the biology of adamantinomatous craniopharyngioma, this immune-modulating treatment seems promising for the treatment of this cystic tumor in order to reduce surgery and delay or omit radiotherapy.

Clinico-radiological correlation of pituitary stalk interruption syndrome in children with growth hormone deficiency.

PURPOSE: To analyze the clinical, hormonal, and radiological characteristics of Pituitary stalk interruption syndrome (PSIS) in children with growth hormone deficiency (GHD). METHODS: This is a prospective cross-sectional study, conducted over a period of three years in a short stature clinic of tertiary care referral hospital. 57 severe short stature children with proven GHD were included in the study. RESULTS: Among 57 children with GHD, 14 (24%) were diagnosed as PSIS. The mean age at diagnosis was 11.8 ± 2.6years. The male to female ratio was 2.5:1. Nine (64%) children had multiple pituitary hormone deficiency (MPHD) and 5 (36%) had isolated growth hormone deficiency (IGHD). In spite of absent or ectopic posterior pituitary (EPP)in Magnetic Resonance Imaging (MRI) of PSIS cohorts, only one had Arginine vasopressin (AVP) deficiency. EPP was seen near median eminence in 6 (44%), elsewhere in 4 (28%), and absent in 4 (28%)children. The height gain following growth hormone therapy was better in PSIS cohorts as compared to non-PSIS. CONCLUSION: Male gender, breech presentation, external congenital anomalies like cryptorchidism, midline defects and nystagmus were more common in children with PSIS. MPHD were more frequently seen in PSIS whereas IGHD in non-PSIS cohort. AVP deficiency is very rare in PSIS despite of absent or ectopic posterior pituitary in MRI. High index of clinical suspicion in all severe short stature may lead to early diagnosis and prompt initiation of growth hormone treatment for better outcome.

Association of Homozygous PROP1 Mutation in a Saudi Family with Combined Pituitary Hormone Deficiency.

Background and Objectives: Combined pituitary hormone deficiency (CPHD) is a rare heterogeneous disease. It is characterized by the deficiency of growth hormone (GH) and shortage of at least one or more other hormones of the pituitary gland including thyroid-stimulating hormone (TSH), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and prolactin. Rare pathogenic variants in nearly 30 genes have been identified as an underlying cause of CPHD pathogenicity. Among these genes, paired-like homeobox 1 (PROP1) has been reported to be the most common cause of CPHD. Materials and Methods: In the present study, we investigated a large family of Saudi origin with three adult sisters suffering from short stature in combination of secondary amenorrhea. Results: Whole-exome sequencing followed by Sanger sequencing shows a homozygous missense variant (NM_006261.5; c.211C > T; p.R71C) in the PROP1 gene segregating with the disease phenotype within the family. In silico analysis studies show that this variant is highly conserved among several orthologues and is predicted as likely pathogenic using various bioinformatics tools. Conclusions: Our finding presents the first Saudi familial case of autosomal recessive form of CPHD caused by the PROP1 variant.

Why do patients with hypopituitarism still present an increased mortality?

Hypopituitarism is defined as a lack or decreased secretion of one or several pituitary hormones. It can result from diseases of the pituitary gland or from pathologies of the superior regulatory center, i.e. the hypothalamus, thereby decreasing hypothalamic releasing hormones and consequently the pituitary hormones. It is still a rare disease with an estimated prevalence of 30-45 patients/100,000 and an incidence of 4-5/100,000/year. This review summarizes the currently available data with a focus on etiologies of hypopituitarism, evidence on mortality rates in patients with hypopituitarism, temporal trends in mortality , and associated diseases, pathophysiological mechanisms and risk factors that affect mortality risk in these patients.

Post-Traumatic Hypopituitarism: A Neglected Consequence of Traumatic Brain Injury.

Post-traumatic hypopituitarism (PTHP), described for the first time in 1918, used to be neglected and only considered a rare consequence of traumatic brain injury (TBI). The research conducted in the past 20 years, however, elucidated that it has been significantly underestimated. A PubMed search was conducted in order to find literature on the topic of PTHP. Efforts were made to identify the wide point of view on this problem, from the historical perspective to the most recent data. The pathogenesis of PTHP is heterogenous, and various hypotheses concerning the etiology of this condition have been proposed. Unrecognized and untreated PTHP has negative socioeconomic consequences and influences the quality of life. Although a few attempts to create a screening algorithm have already been performed, there is still no clear answer regarding follow-up. The prevalence of PTHP, a rare consequence of TBI, has been significantly underestimated in the past 20 years. The issue is multifaceted so in order to make reliable guidelines a collaboration of specialists from different fields is required. Due to the increasing prevalence of TBI, and because patients after initial treatment at emergency department usually remain under control of a neurologist, both neurologists and emergency medicine specialists should be aware of clinical picture and mechanisms of PTHP.

Differential Diagnosis in Hypophysitis: First Report on a Spindle Cell Rhabdomyosarcoma of the Pituitary Gland.

Pituitary gland metastases are very rare. Most patients with pituitary gland metastases are asymptomatic; therefore, most cases of this disease are diagnosed during autopsies. Moreover, the four most common primary tumors that metastasize to the pituitary gland are breast, lung, thyroid, and renal carcinomas. We present a very rare case of pituitary metastasis of spindle cell rhabdomyosarcoma (RMS). Our patient presented with headache, visual disorder, panhypopituitarism, and diabetes insipidus. Due to tumor expansion, resection was not possible, so diagnosis was confirmed by biopsy, and chemotherapy and irradiation were administered. Our patient showed widespread spindle cell RMS, which harbors a mutation of myogenic differentiation 1 (MYOD1) and is associated with a poor prognosis. Even high-risk patients can show a remission after chemotherapy and irradiation. In the cases with indistinct lesions in the sella region, pituitary metastasis should always be considered.

Copy number variation in pituitary stalk interruption syndrome: A large case series of sporadic non-syndromic patients and literature review.

Abnormal hypothalamic/posterior pituitary development appears to be a major determinant of pituitary stalk interruption syndrome (PSIS). The observation of familial cases and associated congenital abnormalities suggests a genetic basis. Single-gene mutations explain less than 5% of the cases, and whole exome sequencing has shown heterogeneous results. The present study aimed to assess copy number variation (CNV) using array-based comparative genomic hybridization (aCGH) in patients with non-syndromic PSIS and comprehensively review data from the literature on CNV analysis in congenital hypopituitarism (CH) patients. Twenty-one patients with sporadic CH from our outpatient clinics presented with ectopic posterior pituitary (EPP) and no central nervous system abnormalities on magnetic resonance image (MRI) or any other malformations on physical examination at presentation were enrolled in the study. aCGH using a whole-genome customized 400K oligonucleotide platform was performed in our patients. For the literature review, we searched for case reports of patients with CH and CNV detected by either karyotype or aCGH reported in PubMed up to November 2021. Thirty-five distinct rare CNVs were observed in 18 patients (86%) and two of them (6%) were classified as pathogenic: one deletion of 1.8 Mb in chromosome 17 (17q12) and one deletion of 15 Mb in chromosome 18 (18p11.32p11.21), each one in a distinct patient. In the literature review, 67 pathogenic CNVs were published in 83 patients with CH, including the present study. Most of these patients had EPP (78% out of the 45 evaluated by sellar MRI) and were syndromic (70%). The most frequently affected chromosomes were X, 18, 20 and 1. Our study has found that CNV can be a mechanism of genetic abnormality in non-syndromic patients with CH and EPP. In future studies, one or more genes in those CNVs, both pathogenic and variant of uncertain significance, may be considered as good candidate genes.

Intrasellar Chordoma Mimicking Pituitary Macroadenoma with Hyperprolactinemia and Hypopituitarism: Clinical Images with a Surgical Video.

A purely intrasellar chordoma is rare among skull base chordomas and is recognized as originating from ectopic embryological notochord located in the sella turcica. In view of its rarity and nonspecific symptoms, clinicians may misdiagnose intrasellar chordoma as pituitary adenoma based on preoperative radiographic images. In this report, we present an intrasellar chordoma that clinically mimicked pituitary macroadenoma with hyperprolactinemia and hypopituitarism and was successfully resected by endoscopic endonasal transsphenoidal surgery. This case demonstrated radiographic features that chordoma should be suspected in sellar lesions. The enlarged sellar with thinned remodeled bone without clival destruction was firstly reminiscent of pituitary adenoma, whereas the very high signal on T2-weighted images and heterogeneous enhancement characteristically suggested chordoma. This rare diagnosis must be considered in the preoperative evaluation of sellar lesions because it can affect how the neurosurgeon prepares for surgery and the surgical goals.

Delineating septo-optic dysplasia.

BACKGROUND: Septo-optic dysplasia (SOD), once a variable triad of septum pellucidum defects (SPDs), optic nerve hypoplasia (ONH), and hypopituitarism, has had multiple findings added, with uncertain causes, definitions, and limits. METHOD: Literature review. RESULTS: SOD is a complex vascular sequence with confounders. CONCLUSIONS: Proximal anterior cerebral artery trunk disruptions cause overlapping primary effects, giving ONH alone most often, and isolated SPD less. ONH disruptions can spread to pituitary, SPD disruptions to the cerebral cortex, causing schizencephaly and related anomalies. Pituitary defects are rare without ONH, and cortical findings are rare without SPD. Extensions are unidirectional, so isolated pituitary or cortical defects are separate from SOD. Micro- an- ophthalmia, a suggested ONH variant, is not part of SOD. Disruption by-products can affect development, causing cognitive and endocrine issues, and structural anomalies such as corpus callosum thinning, ventriculomegaly, and hippocampal and olfactory findings. Limbic extensions may also contribute to the same structural defects as by-products. Midline CNS developmental anomalies can act as disruptive foci, most likely through vascular variants, but have separate pathogenesis. Relative frequencies of specific pituitary hormone defects change as SOD rates increase. Increasing relative rates of midline CNS developmental defects and cortical anomalies are consistent with rising levels of exogenous exposures sensitizing to midline predispositions.

Normal or elevated prolactin is a good indicator to show pituitary stalk interruption syndrome in patients with multiple pituitary hormone deficiency.

OBJECTIVES: To determine the importance of serum prolactin (PRL) in the detection of pituitary stalk interruption syndrome (PSIS) in children with multiple pituitary hormone deficiency (MPHD). We hypothesized that PRL elevation might be a diagnostic indicator of pituitary stalk pathologies. METHODS: Clinical, radiological, and laboratory features of the 50 cases of MPHD were studied. RESULTS: The median age at presentation of the 50 cases (52%, n=26 were female) was 6.61 (0.02-18.9) years. PSIS was detected in 60% (n=30), pituitary hypoplasia in 32% (n=16), partial empty sella in 6% (n=3), and only 2% (n=1) was reported as normal. Out of 50 patients, 21.3% (n=10) were hypoprolactinemic, 44.7% (n=19) were normoprolactinemic, and 34% (n=16) were hyperprolactinemic. The median PRL value was 27.85 (4.21-130) ng/mL in patients with PSIS and 5.57 (0-41.8) ng/mL in patients without PSIS. Additional hormone deficiencies, especially ACTH and LH were detected in follow-up. CONCLUSIONS: Patients with normal or high prolactin levels deserve special attention regarding the possibility of PSIS. Furthermore, we emphasize the importance of regular follow-up and monitoring for multiple pituitary hormone deficiencies in all patients with a single pituitary hormone deficiency.

Role of radiosurgery in the treatment of Cushing's disease.

Radiotherapy is a useful adjuvant treatment for patients with Cushing's disease that is not cured by surgery. In particular, Gamma Knife radiosurgery (GKRS) has been increasingly used worldwide as the preferred radiation technique in patients with persistent or recurrent Cushing's disease. The most widely accepted criterion for hormonal remission after GKRS is normalization of urinary free cortisol (UFC) levels. When a clear biological target is not identified, irradiation of the whole pituitary gland can be considered. The 5-year probability of remission is 65%-75%. Normalization of hypercortisolism usually occurs within 3 years from GKRS treatment and control of tumor growth is optimal, approaching more than 90%. No clear predictor of a favorable outcome has emerged up to now, except for the experience of the treating team. In the largest series, development of partial or complete hypopituitarism occurred between 15% and 36%. Severe side effects of GKRS, such as optic neuropathy and oculomotor palsy, are uncommon but have been documented in patients previously exposed to radiation. Recurrence of disease has been reported in as high as 16%-18% of the patients who achieved normalization of UFC levels in the two largest series, whereas smaller series did not describe late failure of GKRS. The reason for this discrepancy is unclear, as is the relationship between hormonal and tumoral recurrence. Another unresolved issue is whether treatment with adrenal blocking drugs can jeopardize the results of GKRS. GKRS is an effective second-line treatment in patients with Cushing's disease not cured by surgery. Hypopituitarism is the most frequent side effect of GKRS, whereas severe neurologic complications are uncommon in radiation-naïve patients.

A Novel Splice-Site Deletion in the POU1F1 Gene Causes Combined Pituitary Hormone Deficiency in Multiple Sudanese Pedigrees.

Pathogenic variants within the gene encoding the pituitary-specific transcription factor, POU class 1 homeobox 1 (POU1F1), are associated with combined pituitary hormone deficiency (CPHD), including growth hormone, prolactin, and thyrotropin stimulating hormone deficiencies. The aim of the study was to identify genetic aetiology in 10 subjects with CPHD from four consanguineous Sudanese families. Medical history, as well as hormonal and radiological information, was obtained from participants' medical records. Targeted genetic analysis of the POU1F1 gene was performed in two pedigrees with a typical combination of pituitary deficiencies, using Sanger sequencing, and whole-exome sequencing was performed in the other two pedigrees, where hypocortisolism and additional neurologic phenotypes were also initially diagnosed. In POU1F1 gene (NM_001122757.2) a novel homozygous splice-site deletion-namely, c.744-5_749del-was identified in all 10 tested affected family members as a cause of CPHD. Apart from typical pituitary hormonal deficiencies, most patients had delayed but spontaneous puberty; however, one female had precocious puberty. Severe post-meningitis neurologic impairment was observed in three patients, of whom two siblings had Dyke-Davidoff-Masson syndrome, and an additional distantly related patient suffered from cerebral infarction. Our report adds to the previously reported POU1F1 gene variants causing CPHD and emphasises the importance of genetic testing in countries with high rates of consanguineous marriage such as Sudan. Genetic diagnostics elucidated that the aetiologies of hypopituitarism and brain abnormalities, identified in a subset of affected members, were separate. Additionally, as central hypocortisolism is not characteristic of POU1F1 deficiency, hydrocortisone replacement therapy could be discontinued. Elucidation of a genetic cause, therefore, contributed to the more rational clinical management of hypopituitarism in affected family members.

High-throughput splicing assays identify missense and silent splice-disruptive POU1F1 variants underlying pituitary hormone deficiency.

Pituitary hormone deficiency occurs in ∼1:4,000 live births. Approximately 3% of the cases are due to mutations in the alpha isoform of POU1F1, a pituitary-specific transcriptional activator. We found four separate heterozygous missense variants in unrelated individuals with hypopituitarism that were predicted to affect a minor isoform, POU1F1 beta, which can act as a transcriptional repressor. These variants retain repressor activity, but they shift splicing to favor the expression of the beta isoform, resulting in dominant-negative loss of function. Using a high-throughput splicing reporter assay, we tested 1,070 single-nucleotide variants in POU1F1. We identified 96 splice-disruptive variants, including 14 synonymous variants. In separate cohorts, we found two additional synonymous variants nominated by this screen that co-segregate with hypopituitarism. This study underlines the importance of evaluating the impact of variants on splicing and provides a catalog for interpretation of variants of unknown significance in POU1F1.

Clinical and Biochemical Features of Hypopituitarism Among Brazilian Children With Zika Virus-Induced Microcephaly.

Importance: The Zika virus infects progenitor neuron cells, disrupts cerebral development, and, in mice, drives hypothalamic defects. Patients with microcephaly caused by congenital Zika infection present with midline cerebral defects, which may result in hypopituitarism. Objective: To analyze postnatal growth and the presence of clinical and biochemical features associated with hypopituitarism in children with congenital Zika infections. Design, Setting, and Participants: In this prospective cohort study at 2 public referral hospitals in Bahia, Brazil, specializing in the treatment of congenital Zika infection, clinical data and growth parameters of 65 patients with the infection were evaluated. Data were analyzed from April 2017 through July 2018. Exposure: Congenital Zika infection. Main Outcomes and Measures: Length, weight, and head circumference were measured at birth and during follow up (ie, at 27 months of life) for each patient. Basal levels of free thyroxine, thyrotropin, cortisol, corticotropin, prolactin, insulin-like growth factor 1, insulin-like growth factor binding protein 3, urine and plasma osmolality, electrolytes, glucose, and insulin were evaluated at the age of 26 months to 28 months. All patients underwent central nervous system computed tomography scans and ophthalmic and otoacoustic evaluations at the time of this investigation or had done so previously. Results: Among 65 patients (38 [58.4%] male; median [interquartile range] age at enrollment, 27 [26-28] months), 61 patients presented with severe brain defects (93.8%), including corpus callosum agenesis or hypoplasia (ie, midline brain defects; 25 patients [38.5%]) and optic nerve atrophy (38 patients [58.5%]). Most patients presented with severe neurodevelopmental delay (62 of 64 patients [96.9%]). Past or present clinical signs of hypopituitarism were rare, occurring in 3 patients (4.6%). Severe microcephaly, compared with mild or moderate microcephaly, was associated with a shorter length by median (interquartile range) z score at birth (-1.9 [-2.5 to -1.0] vs -0.3 [-1.0 to 0]; P < .001), but this difference did not persist at 27 months (-1.6 [-2.3 to -0.3] vs -2.9 [-4.0 to -1.2]; P = .06). Growth hormone deficiency or hypothyroidism were not observed in any patients, and glucose and insulin levels were within reference ranges for all patients. Low cortisol levels (ie, below 3.9 µg/dL) were observed in 4 patients (6.2%). These 4 patients presented with low (ie, below 7.2 pg/mL) or inappropriately low (ie, below 30 pg/mL) corticotropin levels. Low corticotropin levels (ie, below 7.2 pg/mL) were observed in 6 patients (9.2%). Diabetes insipidus was evaluated in 21 patients; it was confirmed in 1 patient (4.8%) and suggested in 3 patients (14.3%). Conclusions and Relevance: This study found that congenital Zika infection with microcephaly was associated with midline brain defects and optic nerve atrophy. Children with congenital Zika infections presented with prenatal growth impairments with a lack of postnatal catch-up, as shown by persistent short length from birth until 27 months; these impairments were not associated with growth hormone deficiency. Patients also presented with severe developmental delay that was not associated with hypothyroidism, while central adrenal insufficiency and diabetes insipidus occurred in some patients.

Mutations in HID1 Cause Syndromic Infantile Encephalopathy and Hypopituitarism.

OBJECTIVE: Precursors of peptide hormones undergo posttranslational modifications within the trans-Golgi network (TGN). Dysfunction of proteins involved at different steps of this process cause several complex syndromes affecting the central nervous system (CNS). We aimed to clarify the genetic cause in a group of patients characterized by hypopituitarism in combination with brain atrophy, thin corpus callosum, severe developmental delay, visual impairment, and epilepsy. METHODS: Whole exome sequencing was performed in seven individuals of six unrelated families with these features. Postmortem histopathological and HID1 expression analysis of brain tissue and pituitary gland were conducted in one patient. Functional consequences of the homozygous HID1 variant p.R433W were investigated by Seahorse XF Assay in fibroblasts of two patients. RESULTS: Bi-allelic variants in the gene HID1 domain-containing protein 1 (HID1) were identified in all patients. Postmortem examination confirmed cerebral atrophy with enlarged lateral ventricles. Markedly reduced expression of pituitary hormones was found in pituitary gland tissue. Colocalization of HID1 protein with the TGN was not altered in fibroblasts of patients compared to controls, while the extracellular acidification rate upon stimulation with potassium chloride was significantly reduced in patient fibroblasts compared to controls. INTERPRETATION: Our findings indicate that mutations in HID1 cause an early infantile encephalopathy with hypopituitarism as the leading presentation, and expand the list of syndromic CNS diseases caused by interference of TGN function. ANN NEUROL 2021;90:149-164.

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

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

Lower Oxytocin Levels Are Associated with Lower Bone Mineral Density and Less Favorable Hip Geometry in Hypopituitary Men.

INTRODUCTION: Hypopituitary patients are at risk for bone loss. Hypothalamic-posterior pituitary hormones oxytocin and vasopressin are anabolic and catabolic, respectively, to the skeleton. Patients with hypopituitarism may be at risk for oxytocin deficiency. Whether oxytocin and/or vasopressin contribute to impaired bone homeostasis in hypopituitarism is unknown. OBJECTIVES: To determine the relationship between plasma oxytocin and vasopressin levels and bone characteristics (bone mineral density [BMD] and hip structural analysis [HSA]) in patients who have anterior pituitary deficiencies only (APD group) or with central diabetes insipidus (CDI group). METHODS: This is a cross-sectional study. Subjects included 37 men (17 CDI and 20 APD), aged 20-60 years. Main outcome measures were fasting plasma oxytocin and vasopressin levels, and BMD and HSA using dual X-ray absorptiometry. RESULTS: Mean BMD and HSA variables did not differ between the CDI and APD groups. Mean BMD Z-scores at most sites were lower in those participants who had fasting oxytocin levels below, rather than above, the median. There were positive associations between fasting oxytocin levels and (1) BMD Z-scores at the spine, femoral neck, total hip, and subtotal body and (2) favorable hip geometry and strength variables at the intertrochanteric region in CDI, but not APD, participants. No associations between vasopressin levels and bone variables were observed in the CDI or ADP groups. CONCLUSIONS: This study provides evidence for a relationship between oxytocin levels and BMD and estimated hip geometry and strength in hypopituitarism with CDI. Future studies will be important to determine whether oxytocin could be used therapeutically to optimize bone health in patients with hypopituitarism.

Clinical Characteristics of Primary Hypophysitis - A Single-Centre Series of 60 Cases.

OBJECTIVE: Clinical data on primary hypophysitis are still scarce. Especially non-surgical cases are underreported. We sought to analyse clinical characteristics of primary hypophysitis, particularly in clinically diagnosed patients. DESIGN: Retrospective single centre study in 60 patients with primary hypophysitis. METHODS: Symptoms, MRI, histopathological findings, treatment and outcomes were analysed in 12 histopathologically and 48 clinically diagnosed patients. Diagnostic criteria for clinical diagnosis were: a) MRI findings compatible with primary hypophysitis; b) course of disease excluding other differential diagnoses. Mean duration of follow-up was 69 months. RESULTS: Female sex was predominant (73%). Fatigue (52%), headache (38%) and diabetes insipidus (38%) were the most frequent symptoms. 42% had a concomitant autoimmune disease. The corticotropic, thyrotropic, gonadotropic, somatotropic axis was impaired in 67%, 57%, 52%, 20%, respectively. Men had a higher number of impaired hormone axes (p=0.022) with the gonadotropic axis being affected more frequently in men (p=0.001). Infundibular thickening (56%) and space occupying lesions (46%) were typical MRI findings. Pituitary size was frequently enlarged at presentation (37%) but diminished during observation (p=0.029). Histopathologically and clinically diagnosed cases did not differ. CONCLUSIONS: The cohort of clinically diagnosed patients did not differ from our histopathologically diagnosed patients or from published cohorts with predominantly surgical patients. Thus, diagnosis of primary hypophysitis using clinical criteria seems feasible.