P561\u2005Pseudohypoaldosteronism secondary to urinary tract infection in infants

Abstract

Hyponatremia with hyperkalemia in infancy is a rare but life-threatening condition. In the first weeks of life, this scenario is usually associated with aldosterone deficiency due to congenital adrenal hyperplasia (CAH). Pseudohypoaldosteronism (PHA) should be considered in the differential diagnosis of CAH in infants with hyperkalemia, hyponatremia and metabolic acidosis. Urinary tract infections and/or urinary tract anomalies are the most common causes of type 1 secondary (transient) PHA. Adequate replacement with intravenous saline and antibiotic therapy is necessary to correct electrolyte levels and metabolic acidosis within 24–48 hours. Recognition of type 1 secondary PHA enables appropriate management, thus avoiding unnecessary investigations and treatment. Here, we presented five chidren that emphasized the clinical and biochemical properties of type 1 secondary PHA. In this study, four male and one female patients whose ages vary between 20 days and 6 months were observed. The mean values of sodium, potassium and bicarbonate were found as 120 ± 8.9 mmol/l, 7.18 ± 0.98 mmol/l, 13.9 ± 6.19, respectively for five patients. Renin and aldosterone levels were high in all patients. All patients had urinary tract infection with different urinary tract anomalies. These anomalies were unilateral ureterovesical junction (UVJ) obstruction in two patients, bilateral vesicoureteral reflux (VUR) with posterior urethral valve (PUV) in one patient, PUV with bilateral UVJ obstruction in one patient, and unilateral VUR in one patient. The electrolyte imbalance and metabolic acidosis improved after treatment with intravenous saline and appropriate antibiotic agents. Also, renin and aldosterone levels were decreased to normal limits after the aforementioned treatments. In this study, our aim was to increase awareness for type 1 secondary PHA among pediatricians. Type 1 secondary PHA should be considered in the presence of hyponatremia, hyperkalemia and metabolic acidosis in infants with urinary tract infections and/or urinary tract anomalies. Also, electrolyte and blood gas monitoring should be done in infants with urinary tract infections.