Hyponatremia is Common in Children Hospitalized with Urinary Tract Infections and Poses an Increased Risk for More Severe Illness

Background. Urinary tract infection (UTI) is the most common bacterial infection in children and may cause significant early and late complications. Hyponatremia was reported in as many as 67.5% children with pyelonephritis. However, only few reports were published on this subject and the clinical significance of this finding has not been sufficiently studied.

Methods. Medical records of children who were hospitalized in Schneider Children`s Medical Center due to UTI from January 2011 to December 2016 were retrospectively reviewed. Our objective was to assess the prevalence of hyponatremia and its clinical significance in this population.

Results. Two hundred and thirty-three files of healthy children (median age 5.5 months) who were hospitalized due to UTI were included in the study. Hyponatremia (Na<135 mEq/L) at admission was present among 114 children (48.9%). Patients with hyponatremia had more severe disease manifested by longer duration of fever prior to admission, longer duration of hospital stay, higher incidence of abnormal findings in renal parenchyma on ultrasound and a higher C- reactive protein (CRP). Hyponatremia was found to be an independent marker for a more complicated course of the disease.

Conclusions. Our findings show that hyponatremia is very common among previously healthy children hospitalized with UTI and correlates with elevated inflammatory markers and a more complicated disease course