Antimicrobial resistance of Shigella isolates causing traveler's diarrhea

Abstract

Shigella isolates were identified as a cause of traveler's diarrhea in 67 (10%) of 675 patients and were tested for resistance to seven antimicrobial agents in a comparative study with those causing nontraveler's diarrhea in Spain. Ampicillin and chloramphenicol resistance was more frequent in Shigella flexneri (60 and 46%, respectively) than in Shigella sonnei (32 and 18%, respectively) and in travel-related isolates (P < 0.05 and 0.04, respectively). Of S. sonnei isolates from patients with traveler's diarrhea, 73 and 54% showed tetracycline and trimethoprim-sulfamethoxazole resistance, respectively, compared with only 8% of isolates from patients without a history of travel to developing countries (P < 0.007 and P < 0.0002). Low-level resistance to cephalosporins was found, whereas quinolone-resistant strains were not detected among travel-related Shigella isolates. Thus, quinolones may be an eflective alternative therapy for travel-related shigellosis.Shigella species remain an important cause of gastrointestinal illness manifested by watery diarrhea that may progress to mucoid bloody diarrhea or dysentery (7). The severity of the disease is determined in part by the infecting species; infections due to Shigella dysenteriae usually progress to dysentery, which may also occur with infections caused by Shigella flexneri, whereas Shigella boydii and Shigella sonnei generally cause a self-limited, watery diarrhea. Shigella species cause gastroenteritis in industrialized as well as in less-developed countries and are also a cause of traveler's diarrhea. It has been shown that the treatment of shigellosis with an appropriate antibiotic to which the Shigella species is susceptible can successfully reduce the diarrhea and systemic symptoms as well as induce shedding of the organism in stool (19,20).Each year 12 million persons travel from an industrialized country to a developing country in the tropics or subtropics (3). These travelers experience a high rate of diarrhea caused by a wide variety of enteric pathogens acquired by ingestion of contaminated food or water (9). Around 50% of Spanish travelers to developing countries develop diarrhea (8). The purpose of this study was to determine the prevalence of antimicrobial resistance among Shigella strains associated with traveler's diarrhea in comparison with the strains isolated from nontravelers from Spain.A total of 675 patients who attended the outpatient travelers' clinic suffering from traveler's diarrhea after a trip to developing countries were included in this study, in addition to 850 patients without such travel history. Of the patients with traveler's diarrhea, six had previously taken cotrimoxazole and three had taken ampicillin. Germany), and the resulting colonies which exhibited characteristics of Shigella spp. were identified by conventional biochemical methods. Subsequently the species were identified with specific antisera against S. flexneri, S. sonnei, and S. dysenteriae (Diagnostics Pasteur, Marnes-la-Coquette, France) and S. boydii (Difco ...

Sensibilidad antimicrobiana entre los serogrupos de <em>Shigellae</em> aislados en la ciudad de Quito-Ecuador

“…Estudios competentes relacionados a la resistencia a antimicrobianos en el patotipo Shigellae en países de Latinoamérica como Brasil, Chile, Cuba, Argentina, y Uruguay reportan una alta resistencia a los antibióticos tri- metoprim/sulfametoxazol, cloranfenicol y ampicilina [19,21,22,25,26]. Mientras que para países como Canadá, Senegal e India se reporta una resistencia a ampicilina y tetraciclina [27].…”

High prevalence of trimethoprim-resistance cassettes in class 1 and 2 integrons in Senegalese Shigella spp isolates

“…Shigella flexneri is the most prevalent serotype in Africa [2][3][4]. Shigellae are noteworthy for their multiple drug resistance, having gradually acquired resistance to most widely used and inexpensive antimicrobial drugs [5][6][7][8].…”

Shigellosis in Subjects with Traveler's Diarrhea Versus Domestically Acquired Diarrhea: Implications for Antimicrobial Therapy and Human Immunodeficiency Virus Surveillance

“…Although a decline over time was not observed, its rate was lower than that detected in subjects with TD in last century. 28 This data may be related to changes to the therapy chosen for diarrhea. Because the proportion of isolates resistant to AMP and SXT increased substantially among Shigella isolates worldwide in the last decade, these drugs are no longer recommended as empirical therapy for shigellosis by the World Health Organization.…”