Hyponatremia in infants with community-acquired infections on hospital admission

Abstract

Acute moderate to severe gastroenteritis is traditionally associated with hypernatremia but recent observations suggest that hypernatremia is currently less common than hyponatremia. The latter has sometimes been documented also in children with acute community-acquired diseases, such as bronchiolitis and pyelonephritis. We investigated the prevalence of dysnatremia in children with acute moderate severe gastroenteritis, bronchiolitis and pyelonephritis. This prospective observational study included 400 consecutive previously healthy infants ≥4 weeks to ≤24 months of age (232 males and 168 females): 160 with gastroenteritis and relevant dehydration, 160 with moderate-severe bronchiolitis and 80 with pyelonephritis admitted to our emergency department between 2009 and 2017. Circulating sodium was determined by means of direct potentiometry. For analysis, the Kruskal-Wallis test and the Fisher’s exact test were used. Hyponatremia was found in 214 of the 400 patients. It was common in gastroenteritis (43%) and significantly more frequent in bronchiolitis (57%) and pyelonephritis (68%). Patients with hyponatremia were significantly younger than those without hyponatremia (3.9 [1.6–13] versus 7.5 [3.4–14] months). The gender ratio was similar in children with and without hyponatremia. Hyponatremia was associated with further metabolic abnormalities (hypokalemia, hyperkalemia, metabolic acidosis or metabolic alkalosis) in gastroenteritis (71%) and pyelonephritis (54%), and always isolated in bronchiolitis. In conclusion, hyponatremia is common at presentation among previously healthy infants with gastroenteritis, bronchiolitis or pyelonephritis. These data have relevant consequences for the nutrition and rehydration management in these conditions.

Are Further Interventions Needed to Prevent and Manage Hospital-Acquired Hyponatraemia? A Nationwide Cross-Sectional Survey of IV Fluid Prescribing Practices

“…Although isotonic maintenance fluids reduce the risk of hospital-acquired hyponatraemia, it will not eliminate the problem completely as hospital-acquired hyponatraemia is common in children receiving isotonic fluids as well [ 36 ]. In addition, sodium is often low in both children and adults on admission [ 37 , 38 ]. Hyponatraemia should therefore always be considered a cause of neurological symptoms in hospitalised patients regardless of the IV treatment.…”

Maintenance Fluid Therapy with Saline, Dextrose-Supplemented Saline or Lactated Ringer in Childhood: Short-Term Metabolic Effects

“…Ionized sodium level was low, i.e., ≤134 mmol/L in the majority of gastroenteritis cases included in this report. Until the eighties, hyponatremia was unusual in gastroenteritis [7]. In the following decades, the frequency of hyponatremia increased [7].…”

“…Until the eighties, hyponatremia was unusual in gastroenteritis [7]. In the following decades, the frequency of hyponatremia increased [7]. The renaissance of breastfeeding, low-salt formulas and the currently recommended early and fast reintroduction of mostly hypotonic fluids in gastroenteritis likely explain this shift [7].…”

“…Ionized sodium, chloride, potassium, pH and carbon dioxide pressure (direct potentiometry), glucose and L-lactate (amperometry) were determined in whole blood in a GEM Premier TM 4000 analyzer [7]. Furthermore, plasma bicarbonate was estimated from pH and carbon dioxide pressure and blood anion gap was calculated by subtracting the concentrations of chloride and bicarbonate from that of sodium [7]. Blood was again sampled if potassium was ≥5.5 mmol/L or lactate ≥2.5 mmol/L and the lowest value was employed [7].…”

“…Furthermore, plasma bicarbonate was estimated from pH and carbon dioxide pressure and blood anion gap was calculated by subtracting the concentrations of chloride and bicarbonate from that of sodium [7]. Blood was again sampled if potassium was ≥5.5 mmol/L or lactate ≥2.5 mmol/L and the lowest value was employed [7].…”