The incidence of transient infantile pseudohypoaldosteronism in Ireland: A prospective study

Aim To review the clinical course, outcome and incidence of infantile salt-wasting associated with urinary tract infection (UTI) and/or urinary tract malformation (UTM) over a two-year surveillance period on the island of Ireland. Methods A two-year (2013-14) prospective surveillance undertaken via the Irish and Ulster Paediatric Surveillance Units. Monthly-prepaid postcards were circulated to consultant paediatricians (n = 260) at all paediatric units on the island of Ireland. Infants under one year of age presenting for the first time with hyponatraemia (Na 5.0mmol/L) associated with urosepsis/UTM were reported. Results All 7 reported patients (6 male) had culture-proven UTI and 5 (71%) also had an underlying UTM (one diagnosed antenatally). Four (57%) patients had a documented elevated serum aldosterone supporting secondary pseudohypoaldosteronism (PHA) as the underlying diagnosis. Data on aldosterone was not reported in the other 3 patients but clinical features were suggestive of secondary PHA. The estimated incidence for the Irish population of transient PHA is 1 per 13,200 total live births per year. Conclusions Salt-wasting is a rare complication of UTI, especially if associated with underlying UTM. Boys appear to be at particular risk.