Surveillance of Antibiotic Susceptibility Patterns among Shigella sonnei Strains Isolated in Belgium during the 18-Year Period 1990 to 2007

Abstract

This study was conducted to determine the frequency and pattern of antimicrobial susceptibility of Shigella sonnei, the predominant species causing shigellosis in Belgium. Between 1990 and 2007, a total of 7,307 strains, mainly (98.2%) isolated from stools, were diagnosed by peripheral laboratories before being confirmed as Shigella strains by serotyping by the National Reference Center of Salmonella and Shigella. A significant increase in resistances to tetracycline, streptomycin, trimethoprim, sulfonamides, and cotrimoxazole (i.e., trimethoprim in combination with sulfonamides) was observed during this period. Since 1998, resistance to nalidixic acid also increased to reach a peak (12.8%) of resistant isolates in 2004. Concomitantly, multidrug resistance (MDR) in this species emerged in 2007, with 82% of total isolates being MDR. However, during this 18-year period, all isolates remained fully susceptible to ciprofloxacin and gentamicin. The work includes the molecular characterization of mechanisms of resistance to ampicillin, tetracycline, chloramphenicol, and cotrimoxazole and class 1 and class 2 integrons. S. sonnei acquired antimicrobial resistance to traditional antibiotics (ampicillin and tetracycline) by horizontal gene transfer, while the genetic stability of transposons was responsible for a high (89%) proportion of resistance to a commonly prescribed antibiotic (cotrimoxazole). Therefore, cotrimoxazole should no longer be considered appropriate as empirical therapy for treatment of shigellosis in Belgium when antibiotics are indicated. Rates of resistance to nalidixic acid should also be attentively monitored to detect any shift in fluoroquinolone resistance, because it represents the first line among antibiotics used in the treatment of shigellosis.

Genetic characteristics and changing antimicrobial resistance among Shigella spp. isolated from hospitalized diarrhoeal patients in Kolkata, India

“…Shigellosis caused by S. sonnei is an emerging trend in India and has been increasingly detected during the past two decades. A similar increase in the incidence of this serotype with greater epidemiological impact has been reported from many Asian countries (Kuo et al, 2008;Vrints et al, 2009). …”

“…During 1999-2003, .60 % of Bangladeshi S. sonnei isolates were resistant to nalidixic acid, but none to ciprofloxacin (Talukder et al, 2006a). In developed countries, although nalidixic acid resistance was common among S. sonnei isolates, the trend of fluoroquinolone resistance is slowly increasing (Kim et al, 2008;Vrints et al, 2009). It is worthwhile mentioning that all S. sonnei isolates in this study were susceptible to ampicillin, which is not used in the treatment of shigellosis in Kolkata.…”

Patrones de susceptibilidad antimicrobiana de cepas de Shigella sonnei aisladas durante tres períodos diferentes en la Región Metropolitana, Chile

“…Sin embargo, su utilización nuevamente se vio restringida debido al surgimiento de cepas resistentes. La rápida emergencia de cepas multi-resistentes se debe en gran parte a su habilidad de adquirir y diseminar genes exógenos asociados con elementos genéticos móviles tales como plásmidos, transposones, integrones e islas genómicas 16 . Actualmente, existe un problema creciente universal respecto al aumento de resistencia antibacteriana de Shigella spp.…”

Characterization of Shigella Strains by Plasmid Profile Analysis and Antibiotic Susceptibility Patterns in a Pediatric Hospital in Ahvaz

“…Ampicillin and sulfamethoxazole-trimethoprim are commonly used as the first-line drugs for the therapy of shigellosis while second-line drugs including the third generation of cephlosporines and fluoroquinolones are used for the treatment of children and adults respectively (11,16). Unluckily, it has been recently reported that the prevalence of resistance to some commonly used antibiotics is increasing in Shigella spp in Iran (17,18 (5,11,19). In our study, the prevalence of ESBL producing Shigella isolates accounted for 11.4 % of all Shigella isolates which is larger than the reports from Iran and other countries (11,20,21).…”