Apparent mineralocorticoid excess: A diagnosis beyond classical causes of severe hypertension in a child.

A genetic defect of 11 ß-hydroxysteroid dehydrogenase causes apparent mineralocorticoid excess syndrome. Since 50 days of life, our patient was hospitalized several times for various reasons including hypokalemia. At the age of 3.3 years, she was diagnosed with severe hypertension (160/120 mmHg). She also had left ventricular hypertrophy and hypertensive retinopathy and referred to our center. Her renal function and electrolytes were normal except for hypokalemia. She was on captopril treatment; nifedipine and propranolol were added. Plasma renin and aldosterone concentrations were 1.13 pg/ml (1-8.2 pg/ml) and 12.2 ng/dl (35-300 ng/dl), respectively. Severe hypertension, hypokalemia, low renin and aldosterone levels pointed to the diagnosis of apparent mineralocorticoid excess syndrome. Strict salt-restricted diet and potassium citrate were ordered. Genetic analysis of the HSD11B2 gene showed c.623G>A (p.Arg208His). Spironolactone was initiated. On follow-up, amiloride was added and her blood pressure was controlled. In patients with severe HSD11B2 mutation, combination therapy of spironolactone with amiloride could be effective in controlling blood pressure.

Monogenic Forms of Hypertension.

Essential hypertension is a highly prevalent disease in the general population. Secondary hypertension is characterized by a specific and potentially reversible cause of increased blood pressure levels. Some secondary endocrine forms of hypertension are common (caused by uncontrolled cortisol, aldosterone, or catecholamines production). This article describes rare monogenic forms of hypertension, characterized by electrolyte disorders and suppressed renin-aldosterone axis. They represent simple models for the physiology of renal control of sodium levels and plasma volume, thus reaching a high scientific interest. Furthermore, they could explain some features closer to the essential phenotype of hypertension, suggesting a mechanistically driven personalized treatment.

[Cardiac arrest with syndrome of apparent mineralocorticoid excess].

Ventricular fibrillation is an unknown complication to the syndrome of apparent mineralocorticoid excess (SAME). This case report describes a young woman admitted with hypo-kalaemia and hypertension. Concentrations of both P-renin and P-aldosterone were low and urinary steroid metabolites revealed an abnormal excretion pattern pointing to the diagnosis of SAME. Three years later the woman suffered from ventricular fibrillation due to the hypokalaemia caused by her disease. This case report demonstrates the need for increased attention on the potassium concentration in patients with SAME.

Remission of hypertension and electrolyte abnormalities following renal transplantation in a patient with apparent mineralocorticoid excess well documented throughout childhood.

Apparent mineralocorticoid excess syndrome (AME) is an autosomal recessive genetic disorder caused by a deficiency in the enzyme 11ß-hydroxysteroid dehydrogenase type 2 (11ß-HSD). We report a 36-year-old male who was hypertensive from birth and was diagnosed with AME at 8 years of age. There was continuous documentation of his hypertension and hypokalemic alkalosis throughout childhood, during which spironolactone and supplemental potassium were administered. At 33 years of age, the patient received a renal transplant, and following this the AME appears to have been cured clinically with remission of his low renin hypertension and hypokalemic alkalosis despite termination of treatment with spironolactone and potassium supplements.

Secondary nephrogenic diabetes insipidus as a complication of inherited renal diseases.

BACKGROUND/AIMS: Nephrogenic diabetes insipidus (NDI) is a serious condition with large water losses in the urine and the risk of hypernatremic dehydration. Unrecognized, repeated episodes of hypernatremic dehydration can lead to permanent brain damage. Primary NDI is due to mutations in either AVPR2 or AQP2. NDI can also occur as a secondary complication, most commonly from obstructive uropathy or chronic lithium therapy. We observed NDI in patients with inherited tubulopathies and aimed to define the clinical and molecular phenotype. METHODS: We reviewed the medical notes of 4 patients with clinical NDI and an underlying molecularly confirmed diagnosis of nephropathic cystinosis, Bartter syndrome, nephronophthisis and apparent mineralocorticoid excess, respectively. RESULTS: The patients all failed to concentrate their urine after administration of 1-desamino[8-D-arginine] vasopressin. None had an identifiable mutation in AVPR2 or AQP2, consistent with secondary NDI. Patients experienced repeated episodes of hypernatremic dehydration, and in 2 cases, NDI was initially thought to be the primary diagnosis, delaying recognition of the underlying problem. CONCLUSION: The recognition of this potential complication is important as it has direct implications for clinical management. The occurrence of NDI in association with these conditions provides clues for the etiology of aquaporin deficiency.

[Endocrine hypertension]. / Hypertension artérielle endocrine.

Endocrine hypertension represents more than half of the causes of secondary hypertension. This entity encompasses several diseases including primary aldosteronism, paraganglioma/pheochromocytoma and Cushing's syndrome. The screening of endocrine hypertension should be performed in all the patients presenting with: (1) a resistant hypertension; (2) a severe hypertension; (3) the coexistence of hypertension with an adrenal adenoma, clinical or biological abnormalities. Clinical signs and symptoms, whenever present, lack specificity, especially for primary aldosteronism where hypertension is usually the unique symptom. Screening is performed by the measurement of several hormones and by a tomodensitometry to study the morphology of the adrenals: the presence of a solitary or multiples adenomas, or hyperplasia. Pheochromocytoma and Cushing's syndrome are very uncommon and should be referred to specialized centres. Primary aldosteronism is a frequent cause of secondary hypertension. Once the diagnosis is obtained, it is essential to differentiate whether it is a surgically correctable form or not. The patients with a bilateral adrenal hyperplasia can be managed effectively by mineralocorticoids receptor antagonist. The adrenalectomy will cure or improve hypertension for the majority of the patients with a lateralized secretion of aldosterone. The diagnosis and the treatment of these disorders can be challenging. However, the diagnosis of endocrine hypertension allows diagnosing surgical correctable form of hypertension, which is not possible in essential hypertension.

A young female with quadriparesis.

We report a case of a young female who presented with acute onset quadriparesis secondary to severe hypokalemia. She was normotensive and had no metabolic alkalosis or kaliuresis. Serum potassium was corrected over the next few days and the quadriparesis resolved completely. A detailed history later on revealed that she had been consuming alternative medication for infertility for a prolonged duration and had discontinued it a month prior. One of the ingredients of this medicine was Glycyrrhiza glabra.

Hypertension and adrenal disorders.

Adrenal disorders causing hypertension can be related to the dysfunction of either the adrenal cortex or the adrenal medulla. These disorders, including congenital adrenal hyperplasia (CAH), owing to 11B-hydroxylase deficiency and to 17alpha-hydroxylase deficiency; apparent mineralocorticoid excess; familial hyperaldosteronism type I; primary aldosteronism; Cushing's syndrome; and familial glucocorticoid resistance, primarily affect the adrenal cortex and cause low-renin hypertension. The classic disorder of the adrenal medulla resulting in hypertension is pheochromocytoma, although hypertension in obesity might also be associated with catecholamine secretion. In this review, we discuss these etiologies and the most recent advances in our knowledge of their pathophysiology, diagnosis, and treatment.