Epidemiology of blood circulation infections caused by nontifoidal salmonellas, serovars and their antimicrobial sensitivities

In this study, between December 2005 and September 2019, in Akdeniz University Hospital Central Laboratory Microbiology Unit; 58 NTS strains which isolated from blood cultures of adult and pediatric patients were evaluated retrospectively. Patients clinical information was accessed using Mia-Med and Medi-Patient information systems. Sensitivities of ampicillin, ceftriaxone, ciprofloxacin, trimethoprim-sulfamethoxazole and azithromycin were determined by E-test method. Minimum inhibitory concentration (MIC) values were interpreted according to EUCAST clinical breakpoints. Existing isolates were serotyped at the National Enteric Pathogens Reference Laboratory. A total of 10 different serotypes were detected. These are S. Enteritidis, S. Infantis, S. Typhimurium, S. Daytona, S. enterica subsp. diarizonae, S. Hadar, S. Kastrup, S. Ndolo, S.enterica subsp. arizonae, S. enterica subsp. designated as salamae. The most common serotype was S. Enteritidis with 82.8% (n=48), while S. Infantis was the second most common with 3.5% (n=2). 54 of the patients (93.1%) had at least 1 comorbid condition. Of the 49 patients whose data were available, 33 (67.3%) were receiving immunosuppressive therapy. The most commonly used immunosuppressive therapy was found to be steroids. Forty (69%) of the 58 isolated strains were susceptible to all antibiotics. In total, 17 (29.3%) of the strains were found resistant to ampicillin, 1 (1.8%) to trimethoprim-sulfamethoxazole, 8 (13.8%) to ciprofloxacin. Ceftriaxone resistance was not detected in any of them. There are 6 strains (10.3%) resistant to two groups of antibiotics. There is 1 strain (1.7%) with 3 drug resistance (MDR). There was no ESBL producing strain in our study. In the comparison of ciprofiloxacin resistance and the causative species, it was found that NTS isolates other than S. Enteritidis caused a higher rate of ciprofiloxacin resistance (p:0.024). No significant difference was found for ampicillin (p: 0.458). In conclusion, iNTS infections are a disease characterized by serious complications and life-threatening infections, especially affecting the immunosuppressive patient group. Antibiotic-resistant NTS infections are a serious problem which threatens public health. In order to prevent the spread of these resistant strains, strict measures to be taken on livestock and food hygiene, limiting the use of antibiotics as much as possible and spreading the rational use of antibiotics are needed.