Invasive salmonellosis in urban Thai children: a ten-year review.

Background: Invasive, extraintestinal salmonellosis carries a significant burden of childhood morbidity especially among infants and young children in developing countries.

Objectives: To determine the clinical manifestations, outcomes, laboratory findings and antimicrobial susceptibility patterns in patients with invasive salmonellosis.

Methods: A retrospective chart review was conducted among children 0-18 years of age diagnosed with invasive salmonellosis receiving care at Queen Sirikit National Institute of Child Health, Bangkok, Thailand, from 2001 to 2010.

Results: We analyzed the records of 229 patients with culture-proven invasive salmonellosis. Sixty-three percent of cases had no documented underlying disease. Fever, diarrhea and respiratory symptoms were reported in 92%, 40% and 29% of cases, respectively. The spectrum of disease included isolated bacteremia (90%), clinical pneumonia (24.8%), bacteremia with meningitis (7.8%), septic arthritis (1.3%) and empyema thoracis (0.4%). Forty-seven of 57 cases presenting with clinical pneumonia had abnormal infiltrations on chest radiograph (20.5% of all cases). Despite the invasive nature of the illness, 53.1% of patients had a normal white blood cell count. Antimicrobial resistance was found among ampicillin (68.3%), chloramphenical (15.2%), trimethoprim-sulfamethoxazole (33.9%), ceftriaxone (17.4%) and ciprofloxacin (3%). The case fatality rate was 4.8%, 91% of whom had an underlying disease. Multivariate analysis indicated that age, underlying liver disease and presence of pneumonia were significant predictors of fatality.

Conclusions: Fever, diarrhea and respiratory symptoms were among the most common presenting symptoms of invasive nontyphoidal salmonellosis. Older age, hepatobiliary disease and presence of pneumonia were associated with increased risk of fatality. Resistance to third-generation cephalosporins poses a major concern for its use as empiric antimicrobial therapy for this condition.