Test Of Anterior Pituitary Function Research Articles

FRI342 Hypophysitis Mimicking As Pituitary Adenoma

Abstract Disclosure: A. Chao: None. A. Dhaliwal: None. K. Yu, MD: None. S.N. Polis: None. N.J. Vernetti: None. S. Nakhle: None. Background: Hypophysitis is defined as inflammation of the pituitary gland and causes include lymphocytic, granulomatous, xanthomatous, and IgG4 related hypophysitis. Hypophysitis can sometimes mimic a pituitary mass. It is more common in the female and associated with pregnancy. Lymphocytic hypophysitis may present with symptoms related to expansion of the pituitary gland and hormone deficiency. Expansion of the gland often causes headaches. Compression of the optic chiasm results in a decrease in the visual field, color perception, and in rare cases, diplopia due to lateral expansion of the pituitary gland.It also affects hypothalamic-pituitary axis and commonly impairs hormone production from corticotrophs, gonadotrophs and thyrotrophs. Patients treated with glucocorticoids can have hormonal recovery and resolutions of imaging findings. Clinical Case: Patient is a 30-year-old, previously healthy, female who initially presented to the emergency department with a worsening headache over the preceding three months. Brain MRI demonstrated a 1.8 cm enhancing mass and the radiologist interpreted the findings as a pituitary macroadenoma. The patient was seen by neurosurgery and was started on high doses of dexamethasone at 4 mg twice a day for three months duration. After treatment, the patient’s headache improved although she reported an 80-pound weight gain. CT of the head three months later reported a prominent pituitary gland in size compatible with history of pituitary adenoma but decreased in size to 0.9 cm. Repeated brain MRI six months after treatment showed resolution of the mass. The patient also noted a cessation of her menstrual cycle around the onset of headache and laboratory evaluation consistent with hypogonadotropic hypogonadism (FSH 5.5 mIU/mL, LH 2.8 mIU/mL and estradiol 22 pg/mL). Regular menstrual cycles returned seven months after glucocorticoid treatment. Almost two years after the onset of her headaches, the patient was referred to the endocrine clinic for further evaluation of fatigue, low libido, and persistent weight gain. Repeat anterior pituitary function tests were unremarkable and showed FSH 5.6 mIU/mL, LH 3.3 mIU/mL, Estradiol 34 pg/mL, Sodium 139 mmol/L, IGF-1 129 ng/mL (-0.4 standard deviation), Ferritin 20 ng/mL, Prolactin 15.6 ng/mL, TSH 4.38 mIU/L, T4 free 1.1 ng/dL, Cortisol AM 10.9 mcg/dL, and Testosterone 13 ng/dL. Conclusion: We present a case of hypophysitis mistaken for a non-functioning macroadenoma with mild mass effect on the undersurface of the optic chiasm, headache and hypogonadotropic hypogonadism. The patient did not have risk factors such as pregnancy or other autoimmune conditions. After glucocorticoid treatment, recovery of hypogonadotropic hypogonadism and resolution of headache, and radiographic findings. Presentation: Friday, June 16, 2023

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

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.

Late-Onset Hypogonadism in a Male Patient with Long COVID Diagnosed by Exclusion of ME/CFS

After the acute phase of COVID-19, some patients have been reported to have persistent symptoms including general fatigue. We have established a COVID-19 aftercare clinic (CAC) to provide care for an increasing number of these patients. Here, we report the case of a 36-year-old man who developed post-COVID fatigue after acute infection with SARS-CoV-2. In the acute phase of COVID-19, the patient’s fever resolved within four days; however, general fatigue persisted for three months, and he visited our CAC 99 days after the initial infection. Examination revealed a high Aging Male’s Symptoms (AMS) score of 44 and low free testosterone (FT) level of 5.5 pg/mL, which meet the Japanese criteria of late-onset hypogonadism (LOH) syndrome. Imaging studies revealed an atrophic pituitary in addition to fatty liver and low bone mineral density. Anterior pituitary function tests showed a low follicle-stimulating hormonelevel and delayed reaction of luteinizing hormone (LH) after gonadotropin-releasing hormone (GnRH) stimulation, indicating the possibility of hypothalamic hypogonadism in addition to primary hypogonadism seen in patients with post-COVID-19 conditions. After the initiation of Japanese traditional medicine (Kampo medicine: hochuekkito followed by juzentaihoto), the patient’s symptoms as well as his AMS score and serum FT level were noticeably improved. Furthermore, follow-up tests of GnRH stimulation revealed improvements in LH responsiveness. Although many patients have been reported to meet the criteria of ME/CFS such as our case, we emphasize the possibility of other underlying pathologies including LOH syndrome. In conclusion, LOH syndrome should be considered a cause of general fatigue in patients with post-COVID-19 conditions and herbal treatment might be effective for long COVID symptoms due to LOH (264 words).

Two Cases of Pembrolizumab-Induced Secondary Adrenal Insufficiency

Title: Two cases of pembrolizumab-induced secondary adrenal insufficiency Background: Although few cases regarding pembrolizumab-induced secondary adrenal insufficiency were reported, it has recently been published that significantly higher prevalence of human leucocyte antigen (HLA)-DR15, B52, and Cw12 was revealed in 11 Japanese patients with immune checkpoint inhibitor-induced secondary adrenal insufficiency as compared with healthy controls and DR15 might be a predictive marker. This is based on the evidence that DR15 has associations with IL-17-mediated autoimmune disease such as Hashimoto’s thyroiditis, and that anti-programmed death 1 (PD-1) inhibitors activate the Th1 and Th17 pathways. We here introduce two Japanese patients with pembrolizumab-induced secondary adrenal insufficiency from a viewpoint of their HLA typing test results. Clinical Case: Case 1. A 52-year old male diagnosed with stage IV lung cancer (squamous non-small cell lung cancer) was treated with chemotherapy consisting of carboplatin, nab-paclitaxel, and pembrolizumab. Six days after the fourth cycle of pembrolizumab, he suffered from hypoglycemia and hyponatremia. Endocrinological examination findings showed ACTH and cortisol deficiency throughout the day, after which a diagnosis of secondary adrenal insufficiency was made based on no response shown in insulin tolerance, anterior pituitary function, and rapid ACTH stimulation tests. Pituitary cell antibody-1 was negative, and no evidence of a swollen/atrophied pituitary gland or space occupying lesion was observed in magnetic resonance imaging (MRI) results. Furthermore, Hashimoto’s thyroiditis was suspected based on anti-thyroid peroxidase antibody positivity. HLA typing test results highly corresponded with the reported results (A24, B52, Cw12, DR4, DR15). Case 2. A 70-year old male was treated with pembrolizumab for recurrence of lung squamous cell carcinoma (stage IV). Two weeks after completion of five cycles, severe diarrhea occurred, suspected to be a side effect of pembrolizumab, which was relieved with temporary use of prednisolone. However, diarrhea recured accompanied with a high fever,eosinophilia, and acute hyponatremia. Based on results showing deficiency of ACTH and cortisol, adrenal insufficiency was suspected. Anterior pituitary function and rapid ACTH stimulation test results supported that diagnosis, while pituitary cell antibody-1 was negative and MRI findings were not remarkable. Notably, completely different HLA typing test results were observed. Conclusion: Similar to the previous report, HLA-A24, B52, Cw12, DR4, and DR15 were found in case 1, whereas all subtypes including HLA-DR15 were lacking in case 2. We think that it should not be given low priority for cases lacking DR15 and the possibility of an association with IL-17 in such cases is required in feature study.

The prevalence of structural pituitary abnormalities by MRI scanning in men presenting with isolated hypogonadotrophic hypogonadism.

Hypogonadotrophic hypogonadism (HH) is commonly associated with ageing, obesity and type 2 diabetes. The indications for pituitary imaging are controversial, and current guidelines are based on small case series. Retrospective case series from a secondary/tertiary endocrinology referral centre. All men presenting to the Edinburgh Centre for Endocrinology and Diabetes with hypogonadotrophic hypogonadism (testosterone <10 nmol/l and normal prolactin) from 2006 to 2013, in whom pituitary MRI was performed (n = 281). All HH patients referred in 2011 (n = 86) were reviewed to assess differences between those selected for pituitary MRI and those who were not scanned. Pituitary MRI was normal in 235 men (83·6%), with 24 microadenomas (8·5%), 5 macroadenomas (1·8%) and 1 craniopharyngioma (0·4%) identified. The remaining 16 (5·7%) comprised a range of minor pituitary abnormalities including small cysts and empty sella. All men with abnormal imaging studies had otherwise normal pituitary function. Imaging abnormalities were associated with a significantly lower age at presentation (50 vs 54 years, P = 0·02), but no differences in testosterone or gonadotrophin levels were observed. Current Endocrine Society guidelines would have prompted imaging in only three of six patients with significant pituitary pathology. Structural pituitary disease is more common in isolated HH than in the general population, and current guidelines do not accurately identify 'at-risk' individuals. Full anterior pituitary function testing has a low yield in patients presenting with hypogonadism. The optimal strategy for determining the need for pituitary imaging remains uncertain.

Cost feasibility study: performing GH stimulation test only not full anterior pituitary function tests for simple short stature

Cost feasibility study: performing GH stimulation test only not full anterior pituitary function tests for simple short stature

Prednisolone markedly reduced serum IgG4 levels along with the improvement of pituitary mass and anterior pituitary function in a patient with IgG4-related infundibulo-hypophysitis

In 2011 a 76 year-old man with a medical history of diabetes, hypertension and autoimmune pancreatitis was admitted to our hospital because of anorexia, general malaise and repeated hypoglycemia. When he was 72 years old, he suffered from pancreatitis, and pancreas head tumor was operated. IgG4-related pancreatitis was diagnosed histopathologically. On admission anterior pituitary function test revealed impaired response of ACTH and cortisol to CRH, and no response of GH, TSH and gonadotropin to GHRH, TRH and LHRH, respectively. Baseline PRL level was elevated. Serum IgG and IgG4 levels were markedly elevated. Pituitary MRI showed significant enlargement of pituitary gland and stalk. Chest CT suggested IgG4-related lung disease. IgG4-related infundibulo-hypophysitis was diagnosed based on the above mentioned past history and results of present examinations. Twenty mg of hydrocortisone, followed by 20 mg of prednisolone (PSL) and 25 μg of levothyroxine markedly reduced serum IgG4 levels and ameliorated the symptom, the size of pituitary and stalk, and anterior pituitary function (TSH, GH and gonadotropin), although diabetes insipidus became apparent due to glucocorticoid administration. This is a typical case of IgG4-related hypophysitis in which PSL causes marked improvement of pituitary mass and pituitary function along with the reduction of serum IgG4 levels.

Central Diabetes Insipidus: A Previously Unreported Side Effect of Temozolomide

Temozolomide (TMZ) is an alkylating agent primarily used to treat tumors of the central nervous system. We describe 2 patients with apparent TMZ-induced central diabetes insipidus. Using our institution's Research Patient Database Registry, we identified 3 additional potential cases of TMZ-induced diabetes insipidus among a group of 1545 patients treated with TMZ. A 53-year-old male with an oligoastrocytoma and a 38-year-old male with an oligodendroglioma each developed symptoms of polydipsia and polyuria approximately 2 months after the initiation of TMZ. Laboratory analyses demonstrated hypernatremia and urinary concentrating defects, consistent with the presence of diabetes insipidus, and the patients were successfully treated with desmopressin acetate. Desmopressin acetate was withdrawn after the discontinuation of TMZ, and diabetes insipidus did not recur. Magnetic resonance imaging of the pituitary and hypothalamus was unremarkable apart from the absence of a posterior pituitary bright spot in both of the cases. Anterior pituitary function tests were normal in both cases. Using the Research Patient Database Registry database, we identified the 2 index cases and 3 additional potential cases of diabetes insipidus for an estimated prevalence of 0.3% (5 cases of diabetes insipidus per 1545 patients prescribed TMZ). Central diabetes insipidus is a rare but reversible side effect of treatment with TMZ.

Testing the hypothalamo-pituitary-adrenal axis

Aims There remains considerable debate about the best way to assess adrenal function. In our unit, adrenal function in children with suspected pituitary disease is initially tested using dynamic testing of the HPA axis (insulin tolerance test (ITT) or glucagon stimulation test (GST)), with failures (peak cortisol Methods This study took place in a single paediatric endocrinology unit. Endocrine records from November 1999– March 2010 identified patients having anterior pituitary function testing with ITT or GST, and also subsequent SST. Demographic, clinical and endocrine data were subsequently extracted from clinical and laboratory records. Results Over the 11 year collection period 509 ITTs and 164 GSTs were performed. Subsequent SSTs for failed tests were performed in 11 (2.2%) ITTs and 18 (11.0%) GSTs. Overall 42 children with paired tests were identified; 19 underwent ITT (median age 15.2 years, 12 males) and 23 GST (median age 8.8 years, 12 males), followed by SST within one year. The correlation coefficient between baseline (9 am) cortisols on the 2 consecutive tests was 0.36 (p=0.02); using a cutoff of ≥200 nmol/L there was concordance in 29/42 (69%). For ITTs there was a correlation coefficient of 0.34 (p=0.15) between the peak ITT cortisol compared to the 30 minute SST value. Using cutoffs of a peak ITT/GST cortisol level of ≥500 nmol/l and ≥550 nmol/l for the 30 minute SST cortisol level there was concordance in 14/19 (73.7%) ITTs. For GST the correlation coefficient was 0.56 (p=0.0057), and concordance in 11/23 (47.8%). Conclusion There is considerable variation in baseline cortisol levels, making its use and also that of incremental cortisol levels unhelpful in the diagnosis of adrenal insufficiency. Whilst there is a better correlation between the SST cortisol levels at 30 minutes and peak cortisol levels during the GST compared to the ITT concordance between tests is better in the latter. It would appear that the ITT is a good diagnostic test for the HPA axis; the GST less so. For patients having a subnormal cortisol response during the GST we would recommend SST testing.

Pituitary apoplexy within a macroprolactinoma

A 61-year-old lady was admitted to hospital with sepsis due to a urinary tract infection. Three days after admission, she suddenly started to have severe headache with visual disturbance and right third nerve palsy. Urgent magnetic resonance angiography excluded internal carotid artery aneurysm but showed a large lesion extending superiorly from the clivus towards the right cerebral peduncle, which was confirmed by a CT scan of the brain. The lesion was initially thought to be a primary or a metastatic brain tumor. CT scans of the thorax, abdomen and pelvis showed no evidence of metastatic disease. MRI scan revealed a huge pituitary adenoma containing hemorrhage. Subsequent pituitary function tests indicated a grossly elevated serum prolactin level and hypopituitarism. Magnetic resonance angiography of the head; CT scans of the brain, thorax, abdomen and pelvis; MRI scan of the pituitary gland; and baseline and dynamic anterior pituitary function testing. Pituitary apoplexy within a macroprolactinoma. Steroid replacement, careful control of fluid and electrolyte balance and conservative nonsurgical management with the dopamine agonist cabergoline resulted in resolution of the patient's headache, improvement of the third nerve palsy and subsequent normalization of the prolactin level, with reduction in size of the prolactinoma on MRI scan.

Prevalence of GH and other anterior pituitary hormone deficiencies in adults with nonsecreting pituitary microadenomas and normal serum IGF‐1 levels

GH is usually the first pituitary hormone to be affected following a pathological insult to the pituitary; however, data on the prevalence of GH deficiency in patients with nonsecreting pituitary microadenomas and normal serum IGF-1 levels are scarce. This study aims to evaluate the prevalence of GH and other anterior pituitary hormone deficiencies, and to determine whether microadenomas per se could be associated with reduced GH response rates to GHRH-arginine stimulation. Analytical, retrospective, two-site case-control study. Thirty-eight patients with nonsecreting pituitary microadenomas (mean size 4.2 mm) and normal serum IGF-1 levels were studied. Anterior pituitary function testing, including the GHRH-arginine test to examine GH reserve, was performed in all patients. Serum IGF-1 levels and peak GH levels in the patients that passed the GHRH-arginine test were compared with 22 age- and BMI-matched healthy controls. Nineteen patients (50%) failed the GHRH-arginine test and had higher body mass index (BMI) than those that passed the GHRH-arginine test and healthy controls. Peak GH levels in patients that passed the GHRH-arginine test were lower compared to healthy controls and 19 patients (50%) had at least one other pituitary hormone deficit. A negative correlation (r = -0.42, P < 0.01) between peak GH levels and BMI was identified, but no correlations were found between peak GH and serum IGF-1 levels. Our data demonstrated that a substantial number of patients with nonsecreting pituitary microadenomas failed the GHRH-arginine test despite normal serum IGF-1 levels, and had at least one other pituitary hormone deficiency, suggesting that nonsecreting microadenomas may not be clinically harmless. We therefore recommend long-term follow-up with periodic basal pituitary function testing, and to consider dynamic pituitary testing should clinical symptoms arise in these patients.

Reliability of the Low Dose Synacthen Test in Children Undergoing Pituitary Function Testing

There are few data in the paediatric literature on the normal cortisol response to stimulation during the low dose synacthen test (LDST) (1 microg). To examine the cortisol responses in children, subsequently presumed to be normal, who had an LDST during anterior pituitary function tests (APFTs). A retrospective review of results in children with short stature and normal growth hormone levels. Of 33 children tested, seven had suboptimal cortisol responses based on accepted criteria (peak <500 nmol/l)--a false positive rate of 21%. Only three of these children had a repeat LDST, which was normal in all cases. The peak cortisol response (median 633, range, 417-1052 nmol/l) was inversely correlated with age (r = -0.44, p < 0.05). One in five tests did not meet normal criteria. This false positive rate (21%) should be borne in mind when interpreting synacthen tests to prevent overdiagnosis of adrenal insufficiency.

Apoplexy accompanying pituitary adenoma as a complication of preoperative anterior pituitary function tests

Pituitary apoplexy occurs as a very rare complication of the pituitary function test. We have experienced two cases of pituitary apoplexy following anterior pituitary function tests for preoperative assessment: a triple bolus test and a TRH test. To elucidate such a rare complication, we outline our two cases and review 28 cases from the literature. The clinical characteristics, etiology, pathophysiology, and diagnostic and therapeutic implications are also discussed. The combined data suggest that pituitary function tests have the potential to precipitate pituitary apoplexy, and its manifestations range from a clinically benign event to a catastrophic presentation with permanent neurological deficits or even death, although most patients may fortunately have a good outcome. We suggest that the pituitary function test should not be done as a routine test, and when such a test is planned, the patient should be observed with caution for any symptomatic changes for at least 2 hours following the test for appropriate treatment. Further, MRI, especially enhanced studies, may provide an earlier diagnosis of the pituitary apoplexy since CT scan images often fail to demonstrate either density changes or obvious enlargement of the pituitary adenoma at the acute stage.

Anterior and Posterior Pituitary Function Testing with Simultaneous Insulin Tolerance Test and a Novel Copeptin Assay

Posterior pituitary function in patients with suspected diabetes insipidus is usually assessed by a water deprivation test. Alternatively, a nonosmotic stimulus such as hypoglycemia may be used to stimulate vasopressin [arginine vasopressin (AVP)] secretion. Plasma AVP measurement may aid in the diagnosis and, especially, differential diagnosis of diabetes insipidus and polydipsia. However, AVP measurement is cumbersome. Copeptin, the stable C-terminal glycopeptide of the AVP prohormone, is stoichiometrically secreted from the posterior pituitary. The aim was to study the value of copeptin levels in the diagnosis of diabetes insipidus during insulin-induced hypoglycemia. A total of 38 patients were studied during insulin-induced hypoglycemia as part of a combined pituitary function test for possible anterior pituitary disease. There were 29 patients who had normal posterior pituitary function, and nine had central diabetes insipidus. Blood sampling was done before and 30, 45, and 90 min after iv insulin injection. Copeptin was measured with a new sandwich immunoassay. Patients with intact posterior pituitary function had basal copeptin levels of 3.7 +/- 1.5 pm, with a maximal increase to 11.1 +/- 4.6 pm 45 min after insulin injection. Copeptin levels in patients with diabetes insipidus were 2.4 +/- 0.5 pm before insulin injection, with a maximum increase to 3.7 +/- 0.7 pm. Both basal and stimulated copeptin levels were lower in patients with diabetes insipidus as compared with patients with intact posterior pituitary function. A stimulated copeptin level 45 min after insulin injection of less than 4.75 pm had an optimal diagnostic accuracy to detect diabetes insipidus. Copeptin measurement may be used to assess posterior together with anterior pituitary function during insulin-induced hypoglycemia.

Idiopathic hypogonadotrophic hypogonadism associated with arachnoid cyst of the middle fossa and forebrain anomalies: Presentation of an unusual case

We report a 22-yr-old male patient with hypogonadotrophic hypogonadism (HH) associated with a giant middle fossa arachnoid cyst (AC) diagnosed by magnetic resonance imaging (MRI). He presented with pubertal and growth delay. He also had learning disabilities and anosmia. Laboratory investigation revealed pre-pubertal levels of testosterone and normal results of the combined test of anterior pituitary function, except for in GnRH acute and prolonged test. Cranial MRI showed an AC in left middle fossa with expansion to suprasellar cisterna and several abnormalities like left temporal lobe hypoplasia, left optic tract and bilateral olfactory bulb hypoplasia and left hypothalamic hypoplasia.

A unique case of combined pituitary hormone deficiency caused by a PROP1 gene mutation (R120C) associated with normal height and absent puberty

We report a 28-year-old-female who presented with primary amenorrhoea, absence of puberty, obesity and normal stature. The subject was clearly short as a child, with a height more than 2 SD below normal until the age of 15 years. The pubertal growth spurt failed to develop. She continued growing at a prepubertal rate until growth ceased at the age of 20 years, reaching her final adult height of 157 cm (SDS -0.86) without hormonal treatment. A combined pituitary hormone stimulation test of anterior pituitary function showed deficiencies of GH, LH and FSH, and low normal serum levels of TSH and PRL. Magnetic resonance imaging revealed a hypoplastic pituitary with markedly reduced pituitary height. In addition, a whole body dual energy X-ray absorptiometry scan showed high levels of body fat (54%). Combined pituitary hormone deficiencies with a hypoplastic pituitary suggested the diagnosis of a Prophet of Pit-1 (PROP1) gene mutation. Normal stature in this case, however, confounded this diagnosis. Sequencing of PROP1 revealed homozygosity for a single base-pair substitution (C to T), resulting in the replacement of an Arg by a Cys at codon 120 (R120C) in the third helix of the homeodomain of the Prop-1 protein. To our knowledge, this is the first report of a patient with a mutation in the PROP1 gene that attained normal height without hormonal treatment, indicating a new variability in the PROP1 phenotype, with important implications for the diagnosis of these patients. We suggest that this can be explained by (i) the presence of low levels of GH in the circulation during childhood and adolescence; (ii) the lack of circulating oestrogen delaying epiphyseal fusion, resulting in growth beyond the period of normal growth; and (iii) fusion of the epiphyseal plates, possibly as a result of circulating oestrogens originating from peripheral conversion of androgens by adipose tissue.

The pituitary gland and hereditary haemochromatosis

A 38-year-old man presented with a 6-month history of decreased libido and erectile failure. Clinical examination revealed slate-grey skin pigmentation and facial telangiectasia. Low plasma testosterone and no gonadotropin response to gonadotropin-releasing hormone were indicative of hypogonadotropic hypogonadism. Anterior pituitary and liver function tests were otherwise normal, as was fasting blood glucose. Serum ferritin was raised: 2559 μg/L (normal 25–400 μ g/L). Genotyping confirmed homozygosity for the Cys282Tyr mutation in the HFE gene on chromosome 6, confirming the clinical and biochemical diagnosis of hereditary haemochromatosis.

Hypopituitarism following traumatic brain injury and aneurysmal subarachnoid hemorrhage: a preliminary report.

Recognition of pituitary hormonal insufficiencies after head injury and aneurysmal subarachnoid hemorrhage (SAH) may be important, especially given that hypopituitarism-related neurobehavioral problems are typically alleviated by hormone replacement. In this prospective study the authors sought to determine the rate and risk factors of pituitary dysfunction after head injury and SAH in patients at least 3 months after insult. Patients underwent dynamic anterior and posterior pituitary function testing. Results of the tests were compared with those of 18 age-, sex-, and body mass index-matched healthy volunteers. The 22 head-injured patients included 18 men and four women (mean age 28+/-10 years at the time of injury) with initial Glasgow Coma Scale (GCS) scores of 3 to 15. Eight patients (36.4%) had a subnormal response in at least one hormonal axis. Four were growth hormone (GH) deficient. Five patients (four men, all with normal testosterone levels, and one woman with a low estradiol level) exhibited an inadequate gonadotroph response. One patient had both GH and thyrotroph deficiency and another had both GH deficiency and borderline cortisol deficiency. At the time of injury, all eight patients with pituitary dysfunction had an initial GCS score of 10 or less and, compared with the 14 patients without dysfunction, were more likely to have had diffuse swelling, seen on initial computerized tomography scans (p < 0.05), and to have sustained a hypotensive or hypoxic insult (p = 0.07). Of two patients with SAH who were studied (Hunt and Hess Grade IV) both had GH deficiency. From this preliminary study, some degree of hypopituitarism appears to occur in approximately 40% of patients with moderate or severe head injury, with GH and gonadotroph deficiencies being most common. A high degree of injury severity and secondary cerebral insults are likely risk factors for hypopituitarism. Pituitary dysfunction also occurs in patients with poor-grade aneurysms. Postacute pituitary function testing may be warranted in most patients with moderate or severe head injury, particularly those with diffuse brain swelling and those sustaining hypotensive or hypoxic insults. The neurobehavioral effects of GH replacement in patients suffering from head injury or SAH warrant further study.

Mineralocorticoid status and endocrine dysfunction in severe hemochromatosis.

Selective iron deposition in the zona glomerulosa of the adrenal cortex is observed in hemochromatosis. Hypoaldosteronism should be excluded before starting venesection, to avoid long-term volume depletion. We evaluated the aldosterone status in patients with hemochromatosis. As other endocrine organs can be affected by the disease as well, we simultaneously evaluated anterior pituitary, gonadal, thyroid and pancreatic beta-cell activity. Nine patients with hereditary or acquired hemochromatosis and highly increased plasma ferritin levels were investigated. In patients, liver cirrhosis had been confirmed histologically. Five patients complained of sexual dysfunction, and one had impaired glucose tolerance. Plasma aldosterone (PA) and renin activity (PRA) were measured after a period of normal (100 mmol/day) and low (10 mmol/day) sodium intake. A combined anterior pituitary function test and a glucagon stimulation test were undertaken to evaluate other endocrine functions. Both PA and PRA levels were decreased in one patient with liver cirrhosis, who also presented attenuated cortisol, prolactin and gonadotrophin secretion. No patients had signs of primary hypoaldosteronism with hyperreninemia. Hypogonadotropic hypogonadism was observed in 3 males and 1 female. Pituitary ACTH reserve was impaired in 2, GH and prolactin response in 1, and thyroid function in none of the patients. Glucagon-stimulated plasma C-peptide was impaired in one patient. In conclusion, primary aldosterone deficiency was not observed in patients with severe iron overload. Hyporeninemic hypoaldosteronism was found in one patient who also presented other endocrinopathies. Hypogonadotropic hypogonadism is the most frequent endocrine abnormality in hemochromatosis.

Residual pituitary function after transsphenoidal hypophysectomy in dogs with pituitary-dependent hyperadrenocorticism.

Pituitary function was assessed before and after transsphenoidal hypophysectomy in 39 dogs with pituitary-dependent hyperadrenocorticism (PDH). Anterior pituitary function was investigated using combined administration of four hypophysiotropic releasing hormones (corticotropin-releasing hormone (CRH), GHRH, GnRH, and TRH) with measurements of ACTH, cortisol, GH, LH, prolactin (PRL), and TSH Pars intermedia function was assessed by measurements of basal plasma alpha-MSH concentrations and adrenocortical function by baseline urinary corticoid/creatinine ratios. At eight weeks after hypophysectomy basal plasma ACTH, cortisol, GH, LH, PRL, and TSH concentrations were significantly lower than before surgery. In seven dogs with elevated alpha-MSH concentrations, the values returned to the normal level after surgery. In the combined anterior pituitary function test there were no plasma GH, LH, PRL, and TSH responses to stimulation, whereas plasma ACTH and cortisol responses were small but significant. Remission of hyperadrenocorticism was obtained in 35 dogs and recurrences occurred in 3 of these within 16 months postoperatively. At 8 weeks after hypophysectomy, these 3 dogs were not discernible, with respect to residual pituitary and adrenocortical function, from the 32 dogs with persisting remission. Urinary corticoid/creatinine ratios in the latter group of dogs did not increase during 22 months after hypophysectomy. In contrast to the presurgical findings, at 8 weeks after hypophysectomy there were significant positive correlations between baseline urinary corticoid/creatinine ratios and basal levels and responses for ACTH, indicating return to normal function of the pituitary-adrenocortical axis. It is concluded that among the adenohypophyseal cells present in the sella turcica after hypophysectomy, the corticotropes have a distinct behavior. Much more so than the other cell types, the unaffected corticotropes tend to remain functional, or a repressed reserve fraction of corticotropes may become functional. This may be due to the removal of the hypothalamic influence of a postulated corticotropin-release inhibiting factor or a diminished inhibitory influence of a postulated paracrine factor. The corticotropes may maintain normocorticism, but may also lead to mild recurrence after relatively long periods of remission.