Clinical profile of neonates with hypernatremic dehydration in a nephrology clinic

The aim of the study was to assess clinical profile of neonates with hypernatremic dehydration (HD) and identify risk factors associated with acute kidney injury (AKI).

A retrospective study included 18 neonates with HD (serum Na ≥150 mmol/L) hospitalized in the Department of Pediatrics and Nephrology between the years 2009-2019.

The age at presentation was 7.5±4.7 days (range 2-18), weight loss was 15.9±8.3% (range 7.1-32.6) and serum Na range was 151- 192 mmol/L (median 155.5 mmol/L). In 12 (67%) neonates, breast or mixed fed, HD occurred due to inadequate milk intake, in 6 (33%) neonates feeding difficulties were secondary to an acute infection. There was positive correlation between serum Na level and percentage weight loss at presentation (r=0.88; p<0.001). In 6 (33%) patients serious complications of HD were found: AKI in 5 patients, convulsions in one. Percentage weight loss was significantly higher in neonates with HD-associated AKI than in neonates with HD without AKI (p<0.01). Serum Na level was marginally higher in neonates with AKI than in those without AKI (p=0.08). In univariate logistic regression analysis, higher percentage of weight loss and higher serum Na level at presentation were important diagnostic factors of AKI in neonates with HD (both p<0.05). ROC analysis determined good diagnostic profile only for percentage weight loss, with a best cut-off value of 24.8%, for predicting AKI in neonates with HD (AUC 0.862, sensitivity 80%, specificity 100%).

Neonatal HD mostly occurs due to inadequate milk intake in breast or mixed fed babies, and rarely due to feeding difficulties in babies affected by an acute infection. Percentage weight loss at presentation has strong association with neonatal HD and is the most important factor of AKI in neonates with HD.