Hypoaldosteronism Research Articles

Hyperkaliämie

There are no typical symptoms in hyperkalemia. Muscle weakness and paraesthesias are found in potassium levels > 7.5 mmol/l. High potassium intake alone does not lead to hyperkalemia, but can cause hyperkalemia if combined with renal dysfunction or certain medication. Acidosis, a common cause, should always be ruled out. If none of these are found, the hyperkalemia is usually caused by a mineralocorticoid deficiency. With regard to therapy, we differentiate between measures for cardioprotection and quick lowering of the potassium level and measures for rising potassium excretion. A diagnostic algorithm is shown.

Regulation of Placental Growth by Aldosterone and Cortisol

During pregnancy, trophoblasts grow to adapt the feto-maternal unit to fetal requirements. Aldosterone and cortisol levels increase, the latter being inactivated by a healthy placenta. By contrast, preeclamptic placental growth is reduced while aldosterone levels are low and placental cortisol tissue levels are high due to improper deactivation. Aldosterone acts as a growth factor in many tissues, whereas cortisol inhibits growth. We hypothesized that in preeclampsia low aldosterone and enhanced cortisol availability might mutually affect placental growth and function. Proliferation of cultured human trophoblasts was time- and dose-dependently increased with aldosterone (P < 0.04 to P < 0.0001) and inhibited by spironolactone and glucocorticoids (P < 0.01). Mineralo- and glucocorticoid receptor expression and activation upon agonist stimulation was verified by visualization of nuclear translocation of the receptors. Functional aldosterone deficiency simulated in pregnant mice by spironolactone treatment (15 μg/g body weight/day) led to a reduced fetal umbilical blood flow (P < 0.05). In rat (P < 0.05; R2 = 0.2055) and human (X2 = 3.85; P = 0.0249) pregnancy, placental size was positively related to plasma aldosterone. Autocrine production of these steroid hormones was excluded functionally and via the absence of specific enzymatic transcripts for CYP11B2 and CYP11B1. In conclusion, activation of mineralocorticoid receptors by maternal aldosterone appears to be required for trophoblast growth and a normal feto-placental function. Thus, low aldosterone levels and enhanced cortisol availability may be one explanation for the reduced placental size in preeclampsia and related disorders.

Regulation of Placental Growth by Aldosterone and Cortisol

During pregnancy, trophoblasts grow to adapt the feto-maternal unit to fetal requirements. Aldosterone and cortisol levels increase, the latter being inactivated by a healthy placenta. By contrast, preeclamptic placental growth is reduced while aldosterone levels are low and placental cortisol tissue levels are high due to improper deactivation. Aldosterone acts as a growth factor in many tissues, whereas cortisol inhibits growth. We hypothesized that in preeclampsia low aldosterone and enhanced cortisol availability might mutually affect placental growth and function. Proliferation of cultured human trophoblasts was time- and dose-dependently increased with aldosterone (P < 0.04 to P < 0.0001) and inhibited by spironolactone and glucocorticoids (P < 0.01). Mineralo- and glucocorticoid receptor expression and activation upon agonist stimulation was verified by visualization of nuclear translocation of the receptors. Functional aldosterone deficiency simulated in pregnant mice by spironolactone treatment (15 μg/g body weight/day) led to a reduced fetal umbilical blood flow (P < 0.05). In rat (P < 0.05; R(2) = 0.2055) and human (X(2) = 3.85; P = 0.0249) pregnancy, placental size was positively related to plasma aldosterone. Autocrine production of these steroid hormones was excluded functionally and via the absence of specific enzymatic transcripts for CYP11B2 and CYP11B1. In conclusion, activation of mineralocorticoid receptors by maternal aldosterone appears to be required for trophoblast growth and a normal feto-placental function. Thus, low aldosterone levels and enhanced cortisol availability may be one explanation for the reduced placental size in preeclampsia and related disorders.

Approach to the Patient with Adrenocortical Carcinoma

Adrenocortical cancer (ACC) is a rare and often aggressive malignancy that requires multidisciplinary expertise for optimal management. It can present with symptoms of rapidly appearing excess steroid secretion or an abdominal mass, or it can be discovered incidentally. Thorough imaging and endocrine evaluations can identify the majority of ACCs amongst adrenal tumors; however, some smaller ACCs are better identified using fluorodeoxyglucose-positron emission tomography/computed tomography scan. Complete resection by an expert surgeon is the only potentially curative treatment for ACC, and tumor spillage should be avoided. Histopathology is important for diagnosis, but immunohistochemistry markers and gene profiling of the resected tumor may become superior to current staging systems to stratify prognosis. Despite complete resection in stage I-III tumors, approximately 40% of patients develop metastasis within 2 yr. Some retrospective studies indicate that adjuvant mitotane therapy prolongs disease-free survival, leading several centers to recommend its administration; prospective studies are under way to provide future evidence-based recommendations. For locally invading ACC, extensive en bloc resection is attempted, followed by adjuvant mitotane and, in selected cases, adjuvant radiotherapy. When ACC is not surgically resectable, mitotane therapy is adjusted to reach serum levels of 14-20 μg/ml. Careful replacement of glucocorticoid and mineralocorticoid deficiency after surgery or mitotane therapy is important; steroid excess from remaining tumor burden should also be controlled to avoid its morbidities. For metastatic disease, combination chemotherapy should be administered, if possible, in the context of multicenter collaborative research protocols. New insights in the molecular pathogenesis of ACC should allow the development of improved targeted therapies.

Polyendocrinopathie auto-immune de type 1 ou syndrome APECED

autoimmune polyendocrinopathy with candidiasis and ectodermal dystrophy (APECED) is a rare autosomal recessive disorder caused by mutations in the autoimmune regulator gene (AIRE). We report the case of a young girl with APECED. an 18 year-old girl born to consanguineous parents consulted for diffuse alopecia. Dermatological examination showed nail and dental enamel dystrophy and angular cheilitis. She had a history of mineralocorticoid deficiency (Addison's disease), hypoparathyroidism, hypogonadism and Biermer's disease, and she had also had chronic mucocutaneous candidiasis since childhood. She was presenting APECED with autoimmune endocrine failure, chronic mucocutaneous candidiasis and abnormalities of ectoderm-derived tissue. Analysis of mutation in the AIRE gene showed the c.769C>T homozygous mutation in exon 6. APECED, a rare autosomal recessive disorder, is a potentially life-threatening autoimmune disease. Chronic mucocutaneous candidiasis is a common and early feature in children. Dermatologists are likely to be the first physicians to diagnose this syndrome.

Monitoring of Therapy in Congenital Adrenal Hyperplasia

Congenital adrenal hyperplasia is a group of disorders caused by defects in the adrenal steroidogenic pathways. In its most common form, 21-hydroxylase deficiency, patients develop varying degrees of glucocorticoid and mineralocorticoid deficiency as well as androgen excess. Therapy is guided by monitoring clinical parameters as well as adrenal hormone and metabolite concentrations. We review the evidence for clinical and biochemical parameters used in monitoring therapy for congenital adrenal hyperplasia. We discuss the utility of 24-h urine collections for pregnanetriol and 17-ketosteroids as well as serum measurements of 17-hydroxyprogesterone, androstenedione, and testosterone. In addition, we examine the added value of daily hormonal profiles obtained from salivary or blood-spot samples and discuss the limitations of the various assays. Clinical parameters such as growth velocity and bone age remain the gold standard for monitoring the adequacy of therapy in congenital adrenal hyperplasia. The use of 24-h urine collections for pregnanetriol and 17-ketosteroid may offer an integrated view of adrenal hormone production but target concentrations must be better defined. Random serum hormone measurements are of little value and fluctuate with time of day and timing relative to glucocorticoid administration. Assays of daily hormonal profiles from saliva or blood spots offer a more detailed assessment of therapeutic control, although salivary assays have variable quality.

Adrenal crisis provoked by dental infection: case report and review of the literature

Primary adrenal insufficiency is an endocrine disorder characterized by cortisol and aldosterone deficiency caused by destruction of the adrenal cortex. Adrenal crisis is a medical emergency with acute symptoms: nausea, vomiting, abdominal pain, fever, hypoglycemia, seizures, hypovolemic shock, and cardiovascular failure. It occurs in patients with chronic adrenal insufficiency who are exposed to additional stress, such as infection, trauma, or surgical procedures. Dental infection is a possible cause of adrenal crisis in patients with chronic adrenal insufficiency, so pediatric endocrinologists and pediatric dentists should be aware of this risk. The purpose of this report was to present a 6-year-old patient in whom Addison disease was diagnosed through adrenal crisis provoked by dental infection. The patient was treated with intravenous rehydration, intravenous hydrocortisone and antibiotics, and extraction of the infected primary tooth. Multidisciplinary approach and collaboration between the pediatric endocrinologist and the pediatric dentist are necessary to enable adequate medical and dental treatment in children with primary adrenal insufficiency.

Sjúkratilfelli - lífshættulegar truflanir á blóðsöltum hjá átta vikna dreng

Hyponatremia is the most common electrolyte abnormality in children and underlying causes are many. It is most often caused by excessive salt loss from the gut but is also associated with severe systemic disorders in which there is actual or apparent aldosterone deficiency, such as congenital adrenal hyperplasia (CAH), which is the most common inherited disorder of aldosterone synthesis, and pseudohypoaldosteronism (PHA). Abscent aldosterone activity also leads to hyperkalemia which is characteristic for PHA and can result in life threatening arrythmias. This is a case report about a boy presenting with life threatening electrolyte disturbances in conjunction with PHA resulting from pyelonephritis and vesicoureteral reflux.

Clinical and genetic heterogeneity of congenital adrenal hypoplasia due to NR0B1 gene mutations

X-linked adrenal hypoplasia congenita (AHC) is a rare disorder caused by mutations or complete deletion of the NR0B1 gene that encodes the DAX-1 protein, an orphan member of the nuclear receptor superfamily. AHC is characterized by adrenal insufficiency in infancy and early childhood. Later, hypogonadotropic hypogonadism (HH) manifests as pubertal failure. We evaluated the clinical, endocrine and molecular characteristics of 12 AHC patients from 5 families diagnosed between 1984 and 2007 in Israel. Most of the boys (10/12) presented with signs of adrenal insufficiency such as salt wasting and failure to thrive during the neonatal period. Aldosterone deficiency usually preceded cortisol deficiency requiring early mineralocorticoid therapy. Serum cortisol levels in the first weeks of life varied from very low to high levels (<2.76 to >1776 nmol/l). Five boys showed signs of precocious sexual development during infancy and childhood, including enlargement of the penis and testes. In four patients the initial diagnoses were erroneous. Molecular analysis of the NR0B1 gene identified point mutations in six patients including a novel splice site mutation in one patient and his family (IVS1-1G-->C). Contiguous gene deletion was found in six patients from two families who manifested impaired mental development. In X-linked AHC caused by different molecular defects in NR0B1 gene, the clinical spectrum of the disease is quite variable and precocious sexual development is a prominent feature. Genetic testing is indicated in boys presenting with salt-wasting with or without cortisol deficiency if congenital adrenal hyperplasia has been ruled out.

Association of a dog leukocyte antigen class II haplotype with hypoadrenocorticism in Nova Scotia Duck Tolling Retrievers

Canine hypoadrenocorticism (Addison's disease) is due to a deficiency of corticosteroids and mineralocorticoids produced by the adrenals. Although this is a relatively uncommon disease in the general dog population, some breeds, including the Nova Scotia Duck Tolling Retriever (NSDTR), are at increased risk for developing hypoadrenocorticism. A prior study has shown that the increased risk is due to a heritable component. This potentially lethal disorder is hypothesized to have an autoimmune etiology, thus the aim of this study was to determine whether genetic susceptibility to hypoadrenocorticism in NSDTRs is associated with genes of the canine major histocompatibility complex [MHC; dog leukocyte antigen system (DLA)]. Samples were collected from NSDTRs diagnosed with hypoadrenocorticism and healthy siblings or country-matched controls. The DLA class II alleles and haplotypes were determined and compared between cases and controls. We found seven different haplotypes of which the haplotype DLA-DRB1*01502/DQA*00601/DQB1*02301 was significantly more prevalent in the diseased dogs (P = 0.044). In addition, these affected dogs also were more likely to be homozygous across the DLA class II region than the control dogs (OR = 6.7, CI = 1.5-29.3, P = 0.011). We also found that homozygous dogs, regardless of their haplotype, tended to have earlier disease onset compared with heterozygous dogs. These data indicate a limited MHC diversity in North American NSDTRs and suggest that the MHC may play a role in the development of hypoadrenocorticism in the NSDTR, supporting the autoimmune origin of the disease.

Mineralocorticoid Deficiency and Treatment in Congenital Adrenal Hyperplasia

Approximately 75%–80% of patients with Congenital Adrenal Hyperplasia (CAH) fail to synthesize sufficient mineralocorticoids to maintain salt and water balance. In most instances genotype can predict mineralocorticoid deficiency in CAH. Early recognition and replacement with 9α-fludrocortisone and salt supplements will prevent development of potentially lethal salt losing crises. In infancy a relative state of aldosterone resistance exists and replacement dose of 9α-fludrocortisone based on body surface area is higher during infancy compared to childhood and adults. Salt supplementation is generally not required after weaning is started. Regular monitoring of blood pressure and measurements of plasma electrolytes and renin are required to prevent complications of under or over dosage.

Mineralocorticoid Deficiency and Treatment in Congenital Adrenal Hyperplasia

Mineralocorticoid Deficiency and Treatment in Congenital Adrenal Hyperplasia

Transient Salt Wasting in POMC-deficiency due to Infection Induced Stress

Obesity is a multifactorial disorder influenced by genetic, behavioral, environmental and cultural factors. A twelve month old male patient was admitted to the hospital because of malaise, irritability, disquietness and obesity. His BMI was 19.8 kg/m (2) and BMI SDS was 1.38. Mental development was normal, and motor skills were mildly delayed most probably due to his obesity. His physical examination was totally normal except obesity and red hair. A history of hypoglycemia on the fourth day of life, which resolved after oral glucose administration, was reported. The child had been hyperphagic from the first weeks of life and had aggressive behavior when food was denied. The body weight of the patient increased dramatically during the first year of life. Based on the clinical features and laboratory findings (the overgrowth syndrome, red hair, hypoglycemia and hypocortisolism) the patient was diagnosed as POMC deficiency and the diagnosis was confirmed by genetic studies. Hypoglycemia and apnea episodes ceased as he was put on hydrocortisone but he developed relative mineralocorticoid deficiency during a urinary tract infection. In POMC deficiency, relative mineralocorticoid deficiency should be in mind in episodes of severe stress and therapy should be initiated.

Hyporeninemic hypoaldosteronism in a child with chronic kidney disease—is this condition renoprotective?

Hyporeninemic hypoaldosteronism in a child with chronic kidney disease—is this condition renoprotective?

Attenuation of peripheral salt taste responses and local immune function contralateral to gustatory nerve injury: effects of aldosterone

Dietary sodium restriction coupled with axotomy of the rat chorda tympani nerve (CTX) results in selectively attenuated taste responses to sodium salts in the contralateral, intact chorda tympani nerve. Converging evidence indicates that sodium deficiency also diminishes the activated macrophage response to injury on both the sectioned and contralateral, intact sides of the tongue. Because a sodium-restricted diet causes a robust increase in circulating aldosterone, we tested the hypothesis that changes in neurophysiological and immune responses contralateral to the CTX could be mimicked by aldosterone administration instead of the low-sodium diet. Taste responses in rats with CTX and supplemental aldosterone for 4-6 days were similar to rats with CTX and dietary sodium restriction. Responses to sodium salts were as much as 50% lower compared with sham-operated and vehicle-supplemented rats. The group-related functional differences were eliminated with lingual application of amiloride, suggesting that a major transduction pathway affected was through epithelial sodium channels. Consistent with the functional results, few macrophages were observed on either side of the tongue in rats with CTX and aldosterone. In contrast, macrophages were elevated on both sides of the tongue in rats with CTX and the vehicle. These results show that sodium deficiency or administration of aldosterone suppresses the immune response to neural injury, resulting in attenuation of peripheral gustatory function. They also show a potential key link among downstream consequences of sodium imbalance, taste function, and immune activity.

Homozygous nonsense and frameshift mutations of the ACTH receptor in children with familial glucocorticoid deficiency (FGD) are not associated with long‐term mineralocorticoid deficiency

ObjectiveFamilial glucocorticoid deficiency (FGD) is a rare autosomal recessive disease characterized by isolated glucocorticoid deficiency with preserved mineralocorticoid secretion. Mutations in the ACTH receptor (MC2R) account for approximately 25% of all FGD cases, but since these are usually missense mutations, a degree of receptor function is frequently retained. A recent report, however, suggested that disturbances in the renin–aldosterone axis were seen in some patients with potentially more severe MC2R mutations. Furthermore, MC2R knock out mice have overt aldosterone deficiency and hyperkalaemia despite preservation of a normal zona glomerulosa. We wished to determine whether a group of patients with severe nonsense mutations of the MC2R exhibited evidence of mineralocorticoid deficiency, thereby challenging the conventional diagnostic feature of FGD which might result in diagnostic misclassification.DesignClinical review of patients with nonsense MC2R mutations.PatientsBetween 1993 and 2008, 164 patients with FGD were screened for mutations in the MC2R. Totally 42 patients (34 families) were found to have mutations in the MC2R. Of these, 6 patients (4 families) were found to have homozygous nonsense or frameshift mutations.ResultsMild disturbances in the renin–angiotensin–aldosterone axis were noted in four out of six patients, ranging from slightly elevated plasma renin levels to low aldosterone levels, although frank mineralocorticoid deficiency or electrolyte disturbance were not found. No patient required fludrocortisone replacement.ConclusionSevere nonsense and frameshift MC2R mutations are not associated with clinically significant mineralocorticoid deficiency and are thus unlikely to require long-term mineralocorticoid replacement.

Cardiovascular Disease Risk in Adult Women with Congenital Adrenal Hyperplasia Due to 21-Hydroxylase Deficiency

Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is a common autosomal recessive disorder characterized by impaired cortisol biosynthesis, with or without aldosterone deficiency, and androgen excess. Patients with the classic (severe) form also have epinephrine deficiency. Patients with CAH have an increased prevalence of risk factors for cardiovascular disease including obesity, hypertension, and insulin resistance. Androgen excess in women appears to be an additional risk factor for cardiovascular disease. Carotid intima-media thickness, a measure of subclinical atherosclerosis, also has been found to be increased in adults with CAH. The multiple hormonal imbalances present in the adult woman with CAH, in combination with chronic glucocorticoid therapy, contribute to cardiovascular disease risk. Further investigation of the predisposition to cardiovascular disease in women with CAH is warranted. Longitudinal studies are needed, and interventions targeting obesity, insulin resistance, hypertension, and hyperandrogenism may offer improved outcome.

A corticotroph pituitary adenoma as the initial presentation of familial glucocorticoid deficiency

CONTEXT; Familial glucocorticoid deficiency (FGD) is a rare autosomal recessive ACTH-resistance syndrome characterized by glucocorticoid deficiency in the absence of mineralocorticoid deficiency. Here, we report the case of a young woman with a corticotroph pituitary adenoma as the initial presentation of FGD. A 15-year-old girl was referred to our institution for a 16 mm pituitary adenoma associated with glucocorticoid deficiency. Clinical and biological features were evocative of FGD. DNA sequencing did not identify mutations in either the melanocortin 2 receptor (MC2R) or the MC2R accessory protein genes, indicating type 3 FGD. Despite adequate glucocorticoid replacement, plasma ACTH levels remained increased and pituitary magnetic resonance imaging (MRI) showed a progression of the tumour size resulting in optic chiasm compression with intra-tumoural haemorrhaging. When the patient was 26 years old, it was decided that she would undergo transsphenoidal surgery. The histomorphological analysis identified a well-individualized pituitary adenoma immunoreactive for ACTH. The proband's sister also exhibited type 3 FGD associated with pituitary hyperplasia upon MRI. This case highlights the relationship between FGD and hyperplasia of ACTH-producing cells, potentially leading to histologically proven pituitary corticotroph adenomas. This observation raises the question of the pituitary MRI's significance in the follow-up of FGD.

Management of the child with congenital adrenal hyperplasia

Classical congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency leads to glucocorticoid and mineralocorticoid deficiency. Management should be viewed as a process of care which requires input from an interdisciplinary team. Glucocorticoid therapy should take the form of hydrocortisone in a starting dose of 15 mg/m(2)/day (divided into three doses), and the dose should be titrated to blood or urine profiles of cortisol and 17-hydroxyprogesterone. Mineralocorticoid replacement (9 alpha-fludrocortisone) requires higher doses in infancy and childhood than in adolescence. The starting dose should be 150 microg/m(2)/day, and the dose thereafter titrated to plasma renin activity and blood pressure. Despite adequate glucocorticoid substitution and concordance with medical therapy, control can be difficult during puberty due to alterations in the clearance of hydrocortisone, and dosing schedules may need to be adjusted to account for this. Follow-up should address the many facets of CAH, which should be assessed at an annual review, and a suggested protocol is presented.

Addison's disease in a monochorionic diamniotic twin pregnancy – Addison disease

Addisons disease is combined with a deficiency of cortisol and aldosterone. In women, the autoimmune form is more common and associated in up to 40% with other autoimmune conditions. Prior to the advant of steroid therapy it was associated with a high maternal mortality. Adrenal antibodies cross the placenta but neonatal adrenal insufficiency is rarely encountered. We here report on a mother who had a spontaneous monochorionic diamniotic (MCDA) twin pregnancy and Addison's disease. Morbus Addison had been diagnosed at the age of 19 years due clinical symptoms of hypotonia, nausea, fatigue and hyperpigmentation. The patient received 25mg hydrocortison and 0,2mg 9-alpha-fluorhydrocortison per day and got pregnant of MCDA twins. Hydrocortison was increased to 50mg/day considering the increased plasam volume in multiple pregnancy and clinical symptoms of nausea. The pregnancy was uneventful until 31 weeks when she was admitted with PPROM. The patient received oxytocin-antagonists during 48 hours and betamethasone. Due to progression of labor she received peridural anaesthesia and parental application of 100mg hydrocortison/6hours. With fully dilatation and both twins in vertex position the first twin developed variable decelerations and a Cesarean section was performed. Both boys had a normal outcome and did not need steroid supplementation (normal cortisol levels) nor ventilation. The mother presented with hypotension and diuresis postnatally but recovered rapidly. When interpreting results of cortisol in pregnancy one should consider that total serum and free cortisol levels are increased and an abnormally low cortisol level may fall within the normal non-pregnant range.