BclI polymorphism of the glucocorticoid receptor gene is associated with increased bone resorption in patients on glucocorticoid replacement therapy.

CONTEXT: Patients with primary adrenal insufficiency (PAI) and patients with congenital adrenal hyperplasia (CAH) receive weight-adapted standard glucocorticoid replacement therapy. Clinically, some patients appear more sensitive to therapeutic administration of glucocorticoids than others. Glucocorticoid sensitivity is at least partially genetically determined by polymorphisms of the glucocorticoid receptor (GR) and might influence bone mineral density (BMD). OBJECTIVES: To determine if bone turnover markers and BMD are associated with the GR gene polymorphism BclI in patients with PAI and CAH. DESIGN AND PATIENTS: A prospective, cross-sectional study including 74 PAI and 38 CAH patients. BMD was evaluated by DXA. Serum levels of bone turnover markers, minerals, vitamins and hormones, and urinary crosslinks were measured. RESULTS: Patients carrying the homozygous BclI polymorphism (GG) had significantly higher serum ß-CrossLaps (0.37 ± 0.34 µg/l; P < 0.05) and urinary collagen crosslinks (NTX, 68.1 ± 32.4 nmol/g; P < 0.005) despite receiving the lowest average daily hydrocortisone dose of 9.9 ± 3.7 mg/m(2) (P < 0.05). The GG genotype occurred significantly more frequently in patients with increased NTX (OR=6.7, 95% CI = 1.78-25.38) than in patients with normal NTX. However, BMD was not significantly different between different allelic variants. No significant differences in associations of the genotypes with outcomes (or in clinical characteristics) were found between the sexes. CONCLUSIONS: Although the sample sizes were relatively small and the results should be interpreted with caution, this study suggests that the homozygous (GG) genotype may be associated with higher bone resorption in adult PAI and CAH patients. GG-carriers needed a lower hydrocortisone dose on average supporting the concept that this GR variant is associated with increased cortisol sensitivity.

Arginine vasopressin-dependent and AVP-independent mechanisms of renal fluid absorption during thirsting despite glucocorticoid-mediated vasopressin suppression.

OBJECTIVE: Glucocorticoids seem to modify the release and effects of plasma arginine vasopressin (pAVP). However, underlying processes are not well understood. This study aimed to evaluate the mechanism of the modulating effects of glucocorticoids on pAVP and renal water reabsorption. DESIGN: Fluid deprivation tests were performed without (d0) and after one (d1) and five days (d5) of oral prednisolone (Pred) pretreatment in a dosage relevant to drug therapy (30 mg/day). PATIENTS: Twelve healthy male volunteers participated in this trial. MEASUREMENTS: Plasma and urinary osmolality, pAVP, renin, aldosterone, plasma atrial natriuretic peptide (ANP) as well as urinary secretion of aquaporin-2 (AQP2) and prostaglandin E(2) (PGE2) were analysed. RESULTS: An appropriate rise in pAVP was observable during thirsting (P < 0.001), which was absent after Pred pretreatment. However, the plasma and urinary osmolality after Pred treatment did not differ when compared with the basal thirsting test. Unchanged urinary AQP2 excretion suggests AVP-independent mechanisms of renal fluid reabsorption. Plasma renin concentration as well as ANP was substantially increased after Pred intake at d1 and d5 (both P < 0.05), which may mediate such AVP-independent mechanisms. Urinary PGE2 secretion was not influenced by Pred pretreatment, making a PGE2-mediated effect on renal AQP2 translocation and water permeability unlikely. Increased efficacy of exogenous desmopressin at d1 and d5 indicates also a relative increase in AVP sensitivity of the tubular cells after Pred intake. CONCLUSIONS: The here presented data are compatible with an increased AVP sensitivity and a partially AVP-independent regulation of AQP2 translocation and renal fluid reabsorption during glucocorticoid treatment.

Differences in the Distribution of IGF-I Concentrations Between European and US Populations.

Context: Method-specific reference intervals (RIs) determine utility of IGF-I as a biomarker in GH-related diseases. Differences between populations might affect applicability of RIs. Objective: To compare population-specific RIs derived from IGF-I routine testing in laboratories in the United States and Europe using the same assay. Design and setting: Uncensored routine IGF-I testing results generated over 5 years in 4 accredited laboratories (US, n = 778 173 males/710 752 females; Europe, n = 23 220 males/40 183 females). Main outcome measures: Construction of RIs by indirect statistical methods designed to use routine testing data (modified Hoffmann approach). Comparison to published RIs, between the US and Europe, and between regions in the United States with lower and higher mean body mass indexes (BMIs). Results: Lower limits (LLs) of RIs calculated from all routine data sets do not differ from the published LLs. The same is true for upper limits (ULs) calculated from European routine data. ULs derived from US routine data are significantly higher (children, 10-18 years [mean, %]: boys + 149.3 ng/mL [+34.6%]; girls + 94.9 ng/mL [+19.8%]); adults (19-95 years: males + 45 ng/mL [+20.3%]; and females + 29.7 ng/mL [+13.8%]). Average IGF-I is higher in samples from Colorado (lower mean BMI) compared with Alabama (P < 0.0001), although the difference is smaller than between each of them and Europe. Conclusions: We provide evidence that in large datasets from the same population, direct sampling and the indirect Hoffmann approach provide comparable RIs. Although LLs are comparable between Europe and the United States, the UL is significantly higher in the United States. We suggest use of adapted RIs for the United States.

Salivary Diagnostic for Monitoring Strenuous Exercise-A Pilot Study in a Cohort of Male Ultramarathon Runners.

Intense physical stress, such as that in ultramarathon running, affects the immune system. For monitoring in sports medicine, non-invasive methods, e.g., salivary analysis, are of interest. This pilot cohort study aimed to assess changes in salivary parameters in response to an ultramarathon. The results were compared to blood parameters. Male, healthy finishers (n = 9, mean age: 48 ± 8.8 years, mean height: 1.8 ± 0.1 m, mean weight: 72.5 ± 7.2 kg, mean BMI: 23.5 ± 1.9 kg/cm²) of a 160 km ultramarathon were included. Saliva and blood samples were collected at three time points: T1 (baseline), T2 (shortly after the ultramarathon) and T3 (after recovery). In saliva, cortisol, testosterone, IL-1ß, IL-6, IL-8, IL-10, TNF-α, albumin, IgA, α-amylase, aMMP-8, and neopterin were assessed via ELISA. In blood, cortisol, testosterone, IL-1ß, IL-6, IL-8, IL-10, TNF-α, blood cell counts, procalcitonin, CRP, osmolality, albumin, and α-amylase were analyzed. The statistical evaluation comprised longitudinal testing and cross-sectional testing between saliva and blood using ratios of T2 and T3 to baseline values. Various parameters in saliva and blood changed in response to the ultramarathon. Comparing blood and saliva, the longitudinal changes of testosterone (p = 0.02) and α-amylase (p = 0.03) differed significantly. Despite the limitations of the study, it underlines that saliva is an interesting option for comprehensive monitoring in sports medicine and necessitates further studies.

The ElonginB/C-Cullin5-SOCS-Box-Complex Is a Potential Biomarker for Growth Hormone Disorders.

Insulin-like growth factor 1 (IGF-1) is the standard biochemical marker for the diagnosis and treatment control of acromegaly and growth hormone deficiency (GHD). However, its limitations necessitate the screening for new specific and sensitive biomarkers. The elonginB/C-cullin5-SOCS-box-complex (ECS-complex) (an intracellular five-protein complex) is stimulated by circulating growth hormone (GH) and regulates GH receptor levels through a negative feedback loop. It mediates the cells' sensitivity for GH and therefore, represents a potent new biomarker for those diseases. In this study, individual ECS-complex proteins were measured in whole blood samples of patients with acromegaly (n = 32) or GHD (n = 12) via ELISA and compared to controls. Hierarchical clustering of the results revealed that by combining the three ECS-complex proteins suppressor of cytokine signaling 2 (SOCS2), cullin-5 and ring-box protein 2 (Rbx-2), 93% of patient samples could be separated from controls, despite many patients having a normal IGF-1 or not receiving medical treatment. SOCS2 showed the best individual diagnostic performance with an overall accuracy of 0.93, while the combination of the three proteins correctly identified all patients and controls. This resulted in perfect sensitivity and specificity for all patient groups, which demonstrates potential benefits of the ECS-complex proteins as clinical biomarkers for the diagnostics of GH-related diseases and substantiates their important role in GH metabolism.

[Transsexualism and transgender medicine - what every internal specialist should know about]. / Transsexualität und Transgender-Medizin ­ Was jeder Internist wissen sollte.

The authors present current findings on transsexualism and its treatment. According to the ICD-10, transsexualism is defined as the "desire to live and be accepted as a member of the opposite sex, usually accompanied by a sense of discomfort with, or inappropriateness of, one's anatomic sex, and a wish to have surgery and hormonal treatment to make one's body as congruent as possible with one's preferred sex." Synonyms of transsexualism are terms such as gender dysphoria reflecting the distress that persons feel due to a mismatch between their gender identity and their sex assigned at birth.The prevalence of transsexualism is estimated to be about 0,6 %. The diagnosis of transsexualism is made by psychiatrists, but at least five more medical specialties (endocrinologist, surgeon, ear, nose and throat specialist, speech therapist and dermatologist) are involved when treating transsexual persons. Hormonal therapy is a very important element of the treatment process; due to the complexity of transsexualism it should be undertaken by endocrinologists with experience and expertise in this field.

Long-term Outcome of Subacute Thyroiditis.

BACKGROUND: Subacute thyroiditis (SAT) is a rare inflammatory disease that presents diagnostic challenges. The underlying pathophysiology and prediction of outcomes are elusive. We investigated the long-term follow-up of SAT for up to 30 years and determined predictors for later hypothyroidism. METHODS: SAT outcome data from 127 patients (age: 47.6 ± 11.0 yrs. , BMI: 24.7±4.8 kg/m²) were analyzed retrospectively. Patients with pre-existing and known causes of hypothyroidism unrelated to SAT were excluded. We also excluded patients without an accelerated erythrocyte sedimentation rate. SAT outcome parameters included anterior neck pain or tenderness of the thyroid, inflammation markers, hypoechoic areas in thyroid ultrasound, hyperthyroidism, fine-needle aspiration, and thyroid scan. Pre-treatment TSH-levels, gender, age, ultrasound findings, anti-thyroid antibodies and markers of inflammation were considered as possible predictors of SAT outcome. RESULTS: More than 26.8% of SAT patients developed permanent hypothyroidism within 3 years of treatment. The patient groups later developing hypothyroidism did not differ in age, BMI, pre-treatment TSH levels or initial dosage of prednisolone treatment. However, high cumulative doses of prednisolone were associated with a higher prevalence of hypothyroidism. Also, women were more likely to develop hypothyroidism (OR: 3.18 (95% CI: 1.14-8.65); p=0.0176). CONCLUSIONS: Our study suggests that one-quarter of patients with SAT develop hypothyroidism in the long-term. Hypothyroidism was predicted by high cumulative doses of prednisolone treatment and female gender. The reported lower prevalence of hypothyroidism in other countries may represent the faster establishment of diagnosis, different treatment protocols, or lower susceptibility to loss of thyroid function. Swift establishment of the diagnosis and rapid tapering of steroids may result in a higher proportion of patients with euthyroidism.

An Update on Addison's Disease.

Addison's disease - the traditional term for primary adrenal insufficiency (PAI) - is defined as the clinical manifestation of chronic glucocorticoid- and/or mineralocorticoid deficiency due to failure of the adrenal cortex which may result in an adrenal crisis with potentially life-threatening consequences. Even though efficient and safe pharmaceutical preparations for the substitution of endogenous gluco- and mineralocorticoids are established in therapy, the mortality in patients with PAI is still increased and the health-related quality of life (HRQoL) is often reduced.PAI is a rare disease but recent data report an increasing prevalence. In addition to the common "classical" causes of PAI like autoimmune, infectious, neoplastic and genetic disorders, other iatrogenic conditions - mostly pharmacological side effects (e. g., adrenal haemorrhage associated with anticoagulants, drugs affecting glucocorticoid synthesis, action or metabolism and some of the novel anti-cancer checkpoint inhibitors) are contributing factors to this phenomenon.Due to the rarity of the disease and often non-specific symptoms at least in the early stages, PAI is frequently not considered resulting in a delayed diagnosis. Successful therapy is mainly based on adequate patient education as a cornerstone in the prevention and management of adrenal crisis. A focus of current research is in the development of pharmacokinetically optimized glucocorticoid preparations as well as regenerative therapies.

Impact of Autoimmune Thyroiditis on Reproductive and Metabolic Parameters in Patients with Polycystic Ovary Syndrome.

BACKGROUND: Autoimmune thyroiditis (AIT) has been found to be associated with polycystic ovary syndrome (PCOS). The aim of this retrospective cohort study using data from a fertility clinic, with patients recruited from 2009 to 2010, was to confirm the higher prevalence of AIT in PCOS and to evaluate the impact of AIT on reproductive and metabolic parameters of PCOS patients. METHODS: Patients comprised 827 PCOS subjects seen for reproductive or metabolic complaints. Patients presenting primarily for thyroid problems were excluded. All patients were tested for the presence of AIT by laboratory testing and thyroid ultrasound. The impact of AIT on PCOS was evaluated by determination of reproductive and metabolic parameters. RESULTS: Patients with PCOS and AIT as compared to those only with PCOS, had a lower prevalence of elevated testosterone (45 vs. 61%; p=0,0001), free androgen index (5,96±5,41 vs. 7,02±7,6; p<0,001) and hyperandrogenemia (66 vs. 78%; p<0,001). Also testosterone levels were lower in PCOS patients with AIT (0,50±0,30 vs. 0,63±0,71; p=0,0006). Consequently, in these patients, hirsutism was less frequent (51 vs. 66%; p=0,0021). There was no difference in the prevalence of acne, alopecia, a-/ or oligomenorrhea or PCO-morphology in the two patient groups. Patients with PCOS and AIT were more obese by 2 kg/m² BMI on average. A higher BMI correlated with a higher TSH value, although all patients were euthyroid. CONCLUSIONS: AIT is more prevalent in PCOS than in controls. PCOS patients with AIT have less severe hyperandrogenemia and hyperandrogenism but are likely to suffer from an elevated metabolic risk.

Cell-type specific regulation of the human 11beta-hydroxysteroid dehydrogenase type 1 promoter.

The intracellular enzyme 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) converts cortisone into the more active metabolite cortisol. Overexpression of 11beta-HSD1 was associated with features of the metabolic syndrome such as obesity or impaired glucose tolerance. Despite this considerable impact of 11beta-HSD1, the human 11beta-HSD1 promoter has not been described in detail yet. We therefore cloned eight different promoter fragments of the 5'-upstream region of the known transcription/translation-start up to -3034 bp into the luciferase-reporter vector pGL3. A low-cost in-house assay was developed and validated to detect firefly and renilla luciferase activity. Promoter fragments were analysed in human HepG2 and undifferentiated and differentiated murine 3T3-L1 cells. A differential regulation of the human 11beta-HSD1 promoter depending upon the cell type was observed. Specifically, a strong repressor of the basal promoter activity was found between -85 and -172 bp in HepG2 cells only, while an additional repressor appeared to be active between -342 and -823 bp in both, the hepatic and the adipose cell line. The presented data suggest a cell-type specific regulation of the 11beta-HSD1 promoter, which is in agreement with existing expression data from animal and human studies. The described promoter constructs will allow subsequent studies about the role of specific hormonal, metabolic and transcription factors to finally characterise the regulation of the human 11beta-HSD1-promoter in more detail.

[Diagnosis of primary hyperaldosteronism]. / Diagnostik des primären Hyperaldosteronismus.

Primary hyperaldosteronism is the most common secondary form of hypertension. Diagnosis of this entity is recommended in hypokalemic hypertension, in therapy-resistant hypertension (at least three 3 drugs and RR > 140/90 mmHg), and in adrenal incidentalomas (= incidentally discovered adrenal tumors). For screening, the ratio between plasma aldosterone (PAC) and plasma renin concentration (PRC) should be measured. In the assessment of PAC/PRC ratio, the discontinuation of some antihypertensive medication and assay-specific cutoff values must be noticed. After a positive screening test, saline infusion test should be done as confirmatory test. In contraindications/impracticability of this test, 24-h urine collection for aldosterone-18-glucuronide under high-sodium diet can be used as alternative confirmatory test. After confirmation of primary hyperaldosteronism, differential diagnosis between aldosterone-producing adenoma and idiopathic hyperaldosteronism has to be done. For this approach, adrenal CT or MRT, posture test and adrenal vein catheterization as gold standard test are available. Whereas therapy of aldosterone-producing adenoma is surgery, idiopathic hyperaldosteronism is to be treated medically by spironolactone.

Effect of exogenous glucocorticoid on osmotically stimulated antidiuretic hormone secretion and on water reabsorption in man.

OBJECTIVE: Glucocorticoids exert tonic suppression of antidiuretic hormone (ADH) secretion. Hypocortisolism in secondary adrenocortical insufficiency can result in a clinical picture similar to the syndrome of inappropriate ADH secretion. On the other hand, in vitro and in vivo results provide evidence for ADH suppression in states of hypercortisolism. To test the hypothesis that ADH suppression is of relevance during glucocorticoid therapy, we investigated the influence of prednisolone on the osmotic stimulation of ADH. DESIGN AND METHODS: Seven healthy men were subjected to water deprivation tests with the measurement of plasma ADH (pADH) and osmolality (posmol) before and after glucocorticoid treatment (5 days 30 mg prednisolone per day). RESULTS: Before glucocorticoid treatment, the volunteers showed a normal test with an adequate increase of pADH (basal 0.54 +/- 0.2 to 1.9 +/- 0.72 pg/ml (mean +/- S.D.)) in relation to posmol(basal 283.3 +/- 8.5 to 293.7 +/- 6 mosmol/kg). After prednisolone intake, pADH was attenuated (<0.4 pg/ml) in spite of an increase of posmol from 289.3 +/- 3.6 to 297.0 +/- 5.5 mosmol/kg. However, urine osmolar concentration increased normally during water deprivation after prednisolone. Urinary cAMP excretion increased during water deprivation without glucocorticoid treatment from 3.56 +/- 0.55 to 6.07 +/- 0.76 micro mol/l, reflecting the increased pADH levels. The rise in cAMP excretion was completely blunted by prednisolone treatment. CONCLUSIONS: We speculate that there may be an ADH-independent stimulation of the formation or function of aquaporin-2 channels by prednisolone and/or a direct osmotic stimulation of water reabsorption independent of ADH and glucocorticoid control.

Reduction in daily hydrocortisone dose improves bone health in primary adrenal insufficiency.

OBJECTIVE: Individuals with primary adrenal insufficiency (PAI) or congenital adrenal hyperplasia (CAH) receive life-long glucocorticoid (GC) replacement therapy. Current daily GC doses are still higher than the reported adrenal cortisol production rate. This GC excess could result in long-term morbidities such as osteoporosis. No prospective trials have investigated the long-term effect of GC dose changes in PAI and CAH patients. METHODS: This is a prospective and longitudinal study including 57 subjects with PAI (42 women) and 33 with CAH (21 women). Bone mineral density (BMD) was measured by dual energy X-ray absorptiometry at baseline and after 2 years. Subjects were divided into three groups (similar baseline characteristics) depending on changes in daily hydrocortisone equivalent dose (group 1: unchanged 25.2±8.2  mg (mean±S.D., n=50); group 2: increased 18.7±10.3 to 25.9±12.0  mg (n=13); group 3: decreased 30.8±8.5 to 21.4±7.2  mg (n=27)). RESULTS: Subjects in group 1 showed normal lumbar and femoral Z-scores which were unchanged over time. Group 2 subjects showed a significant decrease in femoral neck Z-scores over time (-0.15±1.1 to -0.37±1.0 (P<0.05)), whereas group 3 subjects showed a significant increase in lumbar spine and hip Z-scores (L1-L4: -0.93±1.2 to -0.65±1.5 (P<0.05); total hip: -0.40±1.0 to -0.28±1.0 (P<0.05)). No changes in BMI over time were seen within any group. Reduction in GC dose did not increase the risk of adrenal crisis. CONCLUSION: This study demonstrates for the first time that cautious reduction in hydrocortisone equivalent doses leads to increases in BMD, whereas dose increments reduced BMD. These data emphasize the need for the lowest possible GC replacement dose in AI patients to maintain health and avoid long-term adverse effects.

Clinical validation for the aldosterone-to-renin ratio and aldosterone suppression testing using simultaneous fully automated chemiluminescence immunoassays.

BACKGROUND: As larger numbers of hypertensive patients are screened for primary aldosteronism with the aldosterone-to-renin ratio (ARR), automated analyzers present a practical solution for many laboratories. We report the method-specific ARR cutoff determined with direct, automated chemiluminescence immunoassays allowing the simultaneous measurement of plasma aldosterone concentrations (PACs) and plasma renin concentrations (PRCs). METHODS: Method comparisons to commonly employed assays and tandem mass spectrometry were undertaken. Patients were previously diagnosed based on the local ARR cutoff of 1.2 (ng/dl)/(µIU/ml) in samples collected in upright seated position. Lack of aldosterone suppression in response to salt load to less than 5 ng/dl confirmed primary aldosteronism. For the new assays, the optimal ARR cutoff was established in 152 patients with essential hypertension, 93 with primary aldosteronism and 147 normotensive patients. Aldosterone suppression was assessed in 73 essential hypertensive and 46 primary aldosteronism patients. RESULTS: PAC and PRC were significantly correlated to values determined with currently available methods (P < 0.001). In patients with primary aldosteronism, patients with essential hypertension and controls, mean (95% confidence interval) PAC was 28.4 (25.4-31.8), 6.4 (5.9-6.9) and 6.2 (5.6-6.9) ng/dl, respectively. In the same groups, PRC was 6.6 (5.6-7.7), 12.9 (11.2-14.8) and 26.5 (22.2-31.5) µIU/ml. An ARR cutoff of 1.12 provided 98.9% sensitivity and 78.9% specificity. Employing the new assay aldosterone suppression confirmed the diagnosis of primary aldosteronism and essential hypertension using the cutoff of 5 ng/dl. CONCLUSION: Our data demonstrate that the new assays present a convenient alternative for the measurement of PAC and PRC on a single automated analyzer. Availability of these simultaneous assays should facilitate screening and diagnosis of primary aldosteronism.

11beta-hydroxysteroid dehydrogenase types 1 and 2: an important pharmacokinetic determinant for the activity of synthetic mineralo- and glucocorticoids.

The 11beta-hydroxysteroid dehydrogenase (11beta-HSD) system plays a pivotal role in glucocorticoid (GC) and mineralocorticoid (MC) action. Although 11beta-HSD activities are important determinants for the efficacy of synthetic MCs and GCs, corresponding pharmacokinetic data are scanty. Therefore, we characterized 11beta-HSD profiles for a wide range of steroids often used in clinical practice. 11beta-HSD1 and 11beta-HSD2 were selectively examined in 1) human liver and kidney cortex microsomes, and 2) Chinese hamster ovarian cells stably transfected with 11beta-HSD1 or 11beta-HSD2 expression vectors. Both systems produced concordant evidence for the following conclusions. Oxidation of steroids by 11beta-HSD2 is diminished if they are fluorinated in position 6alpha or 9alpha (e.g. in dexamethasone) or methylated at 2alpha or 6alpha (in methylprednisolone) or 16alpha or 16beta, by a methylene group at 16 (in prednylidene), methyloxazoline at 16, 17 (in deflazacort), or a 2-chlor configuration. Whereas the methyl groups also decrease reductase activity (steric effects), fluorination increases reductase activity (negative inductive effect), leading to a shift to reductase activity. This may explain the strong MC activity of 9alpha-fluorocortisol and should be considered in GC therapy directed to 11beta-HSD2-expressing tissues (kidney, colon, and placentofetal unit). 11beta-HSD2 oxidation of prednisolone is more effective than that of cortisol, explaining the reduced MC activity of prednisolone compared with cortisol. Reduction by 11beta-HSD1 is diminished by 16alpha-methyl, 16beta-methyl, 2alpha-methyl, and 2-chlor substitution, whereas it is increased by the Delta(1)-dehydro configuration in prednisone, resulting in higher hepatic first pass activation of prednisone compared with cortisone. To characterize a GC or a MC as substrate for the different 11betaHSDs may be essential for an optimized steroid therapy.

Severe hyponatremia due to hypopituitarism with adrenal insufficiency: report on 28 cases.

OBJECTIVE: Severe hyponatremia due to hypopituitarism and adrenal insufficiency can be life-threatening, and treatment with glucocorticoids is very effective once the diagnosis of the underlying disorder has been made. In our experience, the diagnosis of hypopituitarism in hyponatremic patients is often overlooked. METHODS: In a retrospective study we screened the files of 185 patients with severe hyponatremia (<130 mmol/l) that had been seen in one endocrinological unit of a university hospital between 1981 and 2001 in order to describe the clinical spectrum of patients with hyponatremia and hypopituitarism including secondary adrenal insufficiency. RESULTS: In 139 cases it was possible to clearly ascribe the patients to the pathophysiological groups of (i) primary sodium deficiency, (ii) edematous disorders, and (iii) normovolemic disorders including the "syndrome of inappropriate secretion of antidiuretic hormone" (SIADH). Twenty-eight patients with severe "normovolemic hyponatremia" (serum sodium: 116+/-7 mmol/l, mean+/-s.d.) had hypopituitarism and secondary adrenal insufficiency as shown by basal cortisol measurements and dynamic tests of adrenal function. In 25 cases of this group hypopituitarism (mostly due to empty sella, Sheehan's syndrome and pituitary tumors) had not been recognized previously, and in 12 cases recurrent hyponatremia during previous hospital admissions (up to four times) could be documented. The mean age of these patients (21 women, seven men) was 68 Years. The most frequently occurring clinical signs were missing or scanty pubic and axillary hair, pale and doughy skin, and small testicles in the men. Frequent symptoms like nausea and vomiting, confusion, disorientation, somnolence or coma were similar to those in 91 patients with SIADH. Basal serum cortisol levels in the acutely ill state ranged from 20 to 439 nmol/l (mean+/-s.d.: 157+/-123), while in 30 other severely hyponatremic patients it ranged from 274 to 1732 nmol/l (732+/-351 nmol/l). In most patients with hyponatremic hypopituitarism, plasma antidiuretic hormone levels were inappropriately high, probably due to a failure of endogenous cortisol to suppress the hormone in a stressful situation. All patients recovered after low-dose hydrocortisone substitution. Most patients had other pituitary hormone deficiencies and were appropriately substituted subsequently. CONCLUSIONS: Hypopituitarism including secondary adrenal insufficiency seems to be a frequently overlooked cause of severe hyponatremia. A high level of suspicion is the best way to recognize the underlying disorder. Treatment with hydrocortisone is very effective.

Transactivation via the human glucocorticoid and mineralocorticoid receptor by therapeutically used steroids in CV-1 cells: a comparison of their glucocorticoid and mineralocorticoid properties.

BACKGROUND: Glucocorticoids (GCs) are commonly used for long-term medication in immunosuppressive and anti-inflammatory therapy. However, the data describing gluco- and mineralo-corticoid (MC) properties of widely applied synthetic GCs are often based on diverse clinical observations and on a variety of in vitro tests under various conditions, which makes a quantitative comparison questionable. METHOD: We compared MC and GC properties of different steroids, often used in clinical practice, in the same in vitro test system (luciferase transactivation assay in CV-1 cells transfected with either hMR or hGRalpha expression vectors) complemented by a system to test the steroid binding affinities at the hMR (protein expression in T7-coupled rabbit reticulocyte lysate). RESULTS AND CONCLUSIONS: While the potency of a GC is increased by an 11-hydroxy group, both its potency and its selectivity are increased by the Delta1-dehydro-configuration and a hydrophobic residue in position 16 (16-methylene, 16alpha-methyl or 16beta-methyl group). Almost ideal GCs in terms of missing MC effects, as defined by our in vitro assay, are therefore prednylidene, budesonide, beclomethasone and betamethasone.The MC potency of a steroid is increased by a 9alpha- or a 6alpha-fluoro substituent. A hydrophilic substituent in position 16 (like 16-hydroxylation in triamcinolone) decreases both MC and GC properties. As no substituent that leads to an isolated reduction of GC activity could be characterized in our experiments, 9alpha-fluorocortisol, the most frequently used steroid for MC substitution, seems to be the best choice of available steroids for this purpose.