Transient type 1 pseudo-hypoaldosteronism: report on an eight-patient series and literature review

Eight boys aged 2–12 weeks with urinary tract malformations (UTMs) exhibited features of transient type 1 pseudo-hypoaldosteronism (TPHA1) in the course of urinary tract infection (UTI). Hyponatremia (120.9 ± 5.8 mmol/l), hyperkalemia (6.9 ± 0.9 mmol/l), metabolic acidosis (plasma bicarbonate 11 ± 1.4 mmol/l), and a rise in serum creatinine levels (145 ± 101 μmol/l) were associated with high urinary sodium (Na) and low potassium (K) excretion. Tubular resistance to aldosterone was indicated by high plasma aldosterone concentrations (170.4 ± 100.5 ng/dl), high levels of the plasma aldosterone to potassium ratio (25.2 ± 15.6), and diminished urinary K/Na values (0.31 ± 0.19). With appropriate therapy, serum electrolytes, creatinine, and acid–base balance normalized within 2 weeks. A Medline search revealed another 85 cases of TPHA1 reported to date. All of the 93 patients were less than 7 months of age and 90% were less than 3 months of age, 90.3% suffered from UTM, with associated UTI in 89% of them, 11% had UTM in the absence of UTI, and 9.7% showed isolated UTI. These findings indicate that early infancy is the main contributing factor for TPHA1 to occur and that UTI and UTM are additional factors, with at least one being required for its development.