Hyponatremia and risk factors for death in human visceral leishmaniasis: New insights from a cross-sectional study in Brazil

Abstract

Background: Visceral leishmaniasis (VL) is an important and potentially fatal neglected tropical disease. The aim of this study was to investigate hyponatremia and risk factors for death among VL patients. Methods: This is a cross-sectional study with VL patients admitted to a tertiary hospital in Northeast Brazil, from 2002 to 2009. Patients were divided into two groups: non-survivors and survivors. Hyponatremia was defined as serum sodium<135mEq/L. A logistic regression model was done to investigate risk factors for death. Results: A total of 285 VL patients were included, with mean age 37±15years, and 74% were males. Thirty-four patients died (11.9%). Non-survivors had a significantly higher prevalence of dyspnea (38.2 vs. 16.7%, p=0.003), pulmonary crackles (11.8 vs. 4.0%, p=0.049), dehydration (23.5 vs. 10.8%, p=0.033), oliguria (8.8 vs. 0.8%, p=0.001) and jaundice (47.1 vs. 14.3%, p<0.001). They also presented higher prevalence of hyponatremia (41.9 vs. 24.1%, p=0.035), thrombocytopenia (91.2 vs. 65.3%, p=0.002) and severe hypoalbuminemia (78.3 vs. 35.3%, p<0.001). In multivariate analysis, moderate/severe hyponatremia (OR=2.278, 95% CI=1.046-4.962), thrombocytopenia (OR=5.482, 95% CI=1.629-18.443), jaundice (OR=5.133, 95% CI=1.793-14.696) and severe hypoalbuminemia (OR=6.479, 95% CI=2.124-19.766) were predictors of death. Conclusion: Higher prevalence of dehydration, oliguria, pulmonary symptoms and liver involvement was found in non-survivors VL patients. Hypoalbuminemia and hyponatremia were frequent and significantly associated with mortality.