[Antibiotic resistance in nontyphoidal salmonellae serovars in the Czech Republic]. / Antibiotická rezistence u netyfových sérovaru Salmonella spp. v Ceské republice.

STUDY AIM: To determine antibiotic resistance and incidence of multidrug resistance among Nontyphoidal salmonellae serovars isolated from humans. MATERIAL AND METHODS: Consecutive Salmonella isolates from patients, recovered in 48 microbiology laboratories in May 2012, were analyzed in the respective reference laboratories at the National Institute of Public Health. Strains were re-identified and differentiated into serovars. Their minimum inhibitory concentrations (MICs) to 11 antibiotics were determined by the microdilution method. RESULTS: Of 25 serovars identified among 637 strains of Salmonella enterica, the most frequent were Enteritidis (87.0 %), Typhimurium (4.9 %), and monophasic Typhimurium 4,[5],12:i:- (2.0 %) and Mbandaka (0.6 %); other serovars were rare. Altogether 558 strains (87.6 %) were susceptible to all antibiotics tested and the remaining 79 strains were resistant to one or more antibiotics. The prevalence rates of resistance to individual antibiotics among 637 study strains were as follows: ampicillin 8.5%, tetracycline 5.7%, sulfamethoxazole 5.2%, cipro-floxacin 3.8%, and chloramphenicol 2.5%. Resistance to gentamicin, trimethoprim, and third and fourth generation cephalosporins was rare ( 0.5%) and none of the study strains showed resistance to meropenem. Three producers of extended spectrum beta-lactamase were multidrug resistant and two of them recovered from twins exhibited a different pattern of resistance. Resistant strains were most often assigned to the following serovars: Enteritidis (49.4%), Typhimurium (26.6%), and monophasic Typhimurium (15.2%). While only 7% (39 of 554 strains) of Enteritidis strains were resistant, the serovars Typhimurium and its monophasic variant 4,[5],12:i:- showed high rates of resistance, i.e. 66.7 and 92.3%, respectively. Furthermore, resistance was revealed in all strains of the serovars Virchow (n = 3), Kentucky (n = 1), and Newport (n = 1), in two of three strains of the serovar Infantis, and in one of two strains of the serovar Stanley. All five blood isolates were assigned to the serovar Enteritidis and one of them showed resistance to ciprofloxacin. Of 79 resistant strains, 26.6% showed resistance to ampicillin only and 24.1% to ciprofloxacin only, with multidrug resistance, i.e. resistance to three or more antibiotics, confirmed in 43.0% of strains. CONCLUSION: Despite a relatively low prevalence of resistance to the antibiotics tested among 637 study strains, the following alarming findings were made: Detection of Salmonella enterica strains resistant to ciprofloxacin as the drug of choice or to higher generation cephalosporins and multidrug resistance revealed in two thirds of the strains of the serovar Typhimurium and in all but one strains of its monophasic variant 4,[5],12:i:-.

Enteric fever imported to the Czech Republic: epidemiology, clinical characteristics and antimicrobial susceptibility.

The aim of this study was to describe epidemiological and clinical characteristics of imported enteric fever in Czech travellers and to determine the antimicrobial susceptibility of isolated strains. Retrospective descriptive study included adult patients treated with enteric fever at Hospital Na Bulovce during January 2004-December 2012. A case of typhoid or paratyphoid fever was defined as isolation of Salmonella Typhi or Paratyphi from blood or stool. During the study period, there have been diagnosed 19 cases of enteric fever (12 males and 7 females) with age median of 30 years; 14 cases were caused by Salmonella Typhi and 5 cases by S. Paratyphi A. The infection has been acquired in South Asia (16 patients; 84.2 %), in Africa (Egypt, Angola) in two cases (10.5 %), and in Mexico (1; 5.3 %). Symptoms included fever (all patients), diarrhoea (16 cases; 84.2 %), headache (9; 47.4 %), and abdominal pain (7; 36.8 %). Seventeen patients (89.5 %) were treated with fluoroquinolones; however, the treatment failure was observed in seven of them (41.2 %). Decreased ciprofloxacin susceptibility was detected in eight strains (66.7 %), and one strain (8.3 %) was multidrug resistant. Sequence analysis of quinolone resistance-determining regions (QRDR) of the gyrA gene revealed the presence of amino acid substitutions in all tested isolates with decreased ciprofloxacin susceptibility. Typhoid and paratyphoid fevers represent epidemiologically important diseases that may lead to potentially life-threatening complications. Major issue in the management of enteric fever represents the non-susceptibility of Salmonella strains to fluoroquinolones and other antimicrobials.