Журнал нефрологии и терапии

Transient Pseudohypoaldosteronism in Childrens Secondary to Urinary Tract Infection: Literature Review and Report of 2 Cases

Abstract

Nasser S, Nasser H, Michael J, Soboh S, Ehsan N, Shhadi S, Boshra N and Nasser W

Pseudohypoaldosteronism (PHA) types I and II share hyperkalemia as a predominant finding. PHA is a heterogeneous syndrome characterized by a lack of response of the organs to the mineralocorticoid, and therefore there is loss of salts. Heredity can be autosomal dominant or recessive. It is very rare for other mutations to occur.

Autosomal dominant PHA-I is characterized by mutations in the mineralocorticoid receptor, while Autosomal recessive PHA-I results from mutations in the epithelial sodium channel (ENaC). Clinical expression of renal PHA-I is variable: patients present with salt loss in the neonatal period, failure to thrive, vomiting, and dehydration. Symptoms of renal PHA-I often improve in early childhood and older children.

PHA-II is the result of mutations in a family of serine-threonine kinases called with- no-lysine kinases (WNK) 1 and WNK4. The predominant role of WNK1 is the regulation of cation-Cl− cotransporters (CCCs) such as the sodium chloride cotransporter (NCC), basolateral Na-K-Cl symporter (NKCC1), and potassium chloride cotransporter (KCC1) located within the kidney. WNK4, its primary role in renal physiology, is as a molecular switch between the angiotensin II–aldosterone mediated volume retention and the aldosterone mediated potassium wasting. It also regulates the (NCC) and regulates the function of renal outer medullary potassium (ROMK) channels and ENaCs. Aldosterone inactivates WNK1 and WNK4 activity.

A typical picture of congenital adrenal hyperplasia (CAH) is hyponatremia with hyperkalemia; However, in the presence of pyelonephritis, the same biochemical manifestation can occur with transient PHA-1 also known as type 4 renal tubular acidosis. We report two cases that present hyponatremia accompanied by urinary tract infection, leading to the diagnosis of transient pseudohypoaldosteronism.

The two cases support the idea that the renal tubular resistance to aldosterone is due to urinary tract infection. The two cases are presenting hyperkalemia with hyponatremia, and in whom a diagnosis of congenital adrenal hyperplasia was excluded. It is essential to know that serum aldosterone, urine sodium, and urine cultures may be obtained immediately.