Objectives: The purposes of this study were to investigate the epidemiologic, clinical, and microbiologic features of patients with nontyphoid salmonellosis and to elucidate the impact of resistance on the outcome of nontyphoid salmonellosis in Taiwan. The authors also sought to develop a severity score to derive an objective guideline for antibiotic use in nontyphoid salmonellosis in the era of increasing antibiotic resistance.
Methods: The authors prospectively monitored 311 children with nontyphoid salmonellosis in Kaohsiung, Taiwan. The demographic, clinical, and microbiologic features, underlying diseases, treatment regimen, complications, and outcome were analyzed. In vitro susceptibility testing of the isolates was performed.
Results: The median age of affected patients was 15 months. Salmonella enteritidis B caused 68.5% of episodes, followed by S. enteritidis C1 (11.9%), D (7.7%), C2 (7.1%), E (2.6%), S. choleraesuis (1.6%), and S. paratyphi (0.6%). Sixty percent of isolates were resistant to ampicillin. Patients with bacteremia could not be differentiated from patients without bacteremia on clinical grounds. Patients receiving antibiotics that were inactive in vitro (discordant therapy) had more days of fever and longer hospital stay compared with patients receiving antibiotics that were active in vitro (concordant therapy). Patients receiving no antibiotic treatment had the fewest days of fever and shortest hospital stays, especially among patients with mild illness (severity score, 0–1).
Conclusion: Blood culture should be obtained in patients with nontyphoid salmonellosis to detect bacteremia. In treating antibiotic-resistant nontyphoid salmonellosis, antibiotics are still not mandatory for patients who present with primarily gastrointestinal symptoms and limited signs of systemic inflammation reflected by a low severity score (low C-reactive protein, fewer band cells in peripheral blood, and fewer days of fever before admission). Susceptibility data should be promptly obtained because use of discordant antibiotics appears to prolong illness.