RESUMO
BACKGROUND: The epidemiology of Clostridium difficile infections (CDI) is changing rapidly worldwide; knowledge on the genotypes of C. difficile circulating in specialized geriatric hospitals and their resistance to antibiotics is scarce or non-existent. METHODS: Prospective study of the molecular epidemiology of CDI, conducted in a national geriatric hospital in Costa Rica for a period of 11 months. RESULTS: The study patients exhibited a diverse range of comorbidities, but none were associated with CDI. Polyclonality, including three new ribotypes, and a high level of resistance to antibiotics were determined by analysing the 32 isolates obtained in these cases. Despite the diversity in strains observed, the most frequent types were NAP6/RT002 and NAP2/RT001. NAP9/RT017 was associated with community acquisition. Nineteen types of antimicrobials were used before the onset of diarrhoea in the patients; no particular genotype was associated with the onset of infection or severity. CONCLUSION: Based on the abundance of strain types observed and their resistance to antibiotics in this geriatric hospital, these results contribute to a better overall understanding of the epidemiology of CDI worldwide, and to surveillance programmes targeting geriatric populations.
Assuntos
Clostridioides difficile/classificação , Clostridioides difficile/genética , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Variação Genética , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Clostridioides difficile/isolamento & purificação , Costa Rica/epidemiologia , Diarreia/epidemiologia , Diarreia/microbiologia , Farmacorresistência Bacteriana , Feminino , Hospitais , Humanos , Masculino , Epidemiologia Molecular , Estudos Prospectivos , RibotipagemRESUMO
OBJECTIVE: To assess the susceptibility of 100 isolates of Bacteroides spp. recovered in a major Costa Rican hospital between 2000 and 2008 to several ß-lactams, chloramphenicol, clindamycin and metronidazole. METHODS: Susceptibility to amoxicillin, amoxicillin with clavulanic acid, piperacillin, piperacillin with tazobactam, ticarcillin, ticarcillin with clavulanic acid, cefoxitin, cefotetan, imipenem, chloramphenicol, clindamycin, and metronidazole was determined with the ATB ANA® system. In addition, minimum inhibitory concentrations (MIC) of clindamycin and metronidazole were determined with the broth microdilution method because these drugs are the treatment of choice for anaerobic infections in Costa Rica. Reference strains ATCC® 25285 and ATCC® 29741 were employed as indicated. RESULTS: According to the ATB ANA® system, 93 isolates were resistant to at least one antibiotic. Resistance to ß-lactams was common. By contrast, resistance to ß-lactams supplemented with ß-lactamase inhibitors was rare. All of the strains were inhibited by imipenem and chloramphenicol. By a broth microdilución test, resistance to clindamycin was 20%, with MIC ranging from 64 mg/L to 256 mg/L; all of the strains were susceptible to metronidazole. CONCLUSIONS: The high MIC for clindamycin obtained for the majority of the resistant strains is highly suggestive of the presence of mechanisms of acquired resistance among the isolates, therefore surveillance studies are required to determine its efficacy. The low resistance to metronidazole observed underlines its value as a first-line drug. On the other hand, imipenem could be used to treat infections that do not respond well to metronidazole or clindamycin.
Assuntos
Antibacterianos/farmacologia , Infecções por Bacteroides/microbiologia , Bacteroides/efeitos dos fármacos , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana Múltipla , Bacteroides/isolamento & purificação , Infecções por Bacteroides/epidemiologia , Cloranfenicol/farmacologia , Clindamicina/farmacologia , Costa Rica/epidemiologia , Infecção Hospitalar/epidemiologia , Humanos , Metronidazol/farmacologia , Testes de Sensibilidade Microbiana , Estudos Retrospectivos , Resistência beta-Lactâmica , beta-Lactamas/farmacologiaRESUMO
Because of limitations in infrastructure, the aetiology of infections caused by anaerobic bacteria is seldom determined in clinical laboratories of developing countries. This study reports on the identification of 1010 anaerobic bacterial isolates collected between 1999 and 2008 in a major Costa Rican hospital with the use of two commercial phenotypic systems (RapID 32A and API 20A). Approximately 60% of the isolates were Gram-positive and, among the 35 species of Gram-positive bacteria found, the genera Clostridium, Propionibacterium and Eggerthella, and anaerobic cocci predominated. Twenty eight species were found among 395 isolates of Gram-negative bacteria. Species of Bacteroides were very frequent, followed by species of Prevotella, Veillonella, Fusobacterium and Porphyromonas.