Risk Factors for Nontyphi Salmonella Bacteremia Over 10 Years in Fort-de-France, Martinique, West Indies

Nontyphoidal Salmonella infections can result in bacteremia. This study was undertaken to determine the predictive factors for bacteremia in children aged less than 16 years. Medical data were collected for every child with positive nontyphoidal Salmonella cultures in blood or stools at the University hospital of Martinique, French West Indies, between January 2005 and December 2015. Among 454 patients, 333 were included; 156 cases had confirmed bacteremia, and 177 were included as control group with nontyphoidal Salmonella only isolated in stools. Age at diagnosis, delay before consulting, prematurity, immunosuppression, or hyperthermic seizures were not significantly associated with bacteremia. C-reactive protein was higher in cases of bacteremia (P = 0.01); however, after adjusting to the threshold of 30 mg/L, there was no longer any difference. There were also significant relations for electrolytes such as hyponatremia (odds ratio (OR) = 2.08 [95% CI = 1.31–3.95]; P < 0.01), high urea level (OR = 0.53 [95% CI = 0.32–0.88], P < 0.01). The infecting serotype was the most discriminant risk factor (P < 10−4). Among 28 serotypes isolated between 2005 and 2015, Salmonella panama was the most common serotype: 122 strains (78.2%) were isolated from bacteremic patients versus 60 (33.9%) from nonbacteremic patients (P < 10−4). Salmonella panama was the most important risk factor for bacteremia (OR = 7.37 [95% CI = 3.18–17.1], P < 10−4) even after multivariate analysis (OR = 13.09 [95% CI = 5.42–31.59], P < 10−4). After adjusting for bacteremia, S. panama was associated with a significantly higher body temperature than other Salmonella: 39°C (standard deviation [SD] = 0.92) versus 38.2°C [SD = 1.1], linear regression P < 10−3. Children with Salmonella serotype panama infection were at higher risk of bacteremia than children infected with other Salmonella serotypes.