ABSTRACT
Background: Helicobacter pylori-associated gastroduodenal diseases depends on host characteristics, environmental conditions and bacterial virulence factors, such as cagA, vacA y babA2 gene products. Moreover, peptic ulcer disease has been related with cagA+, vacAs1m1 strains, while metaplasia and gastric cancer has been associated to cagA+, vacAs1 and babA2+ H pylori strains. Gene babA2 has not yet been described in clinical isolates from Chilean patients. Aim: To investigate the presence of cagA, vacA (s and m) and babA2 genes in clinical isolates of H pylori from Chilean patients. Material and Methods: Sixty six isolates from 41 patients were genotyped by PCR, using primers for s1a, s1b, s2, m1, m2, cagA and babA2 genes as previously described. Results: cagA gene was detected in 16 isolates (24.2 percent) while vacAs1a, vacAs1b, vacAs2, vacAm1 and vacAm2 were detected in 28 (42.4 percent), 14 (21.2 percent), 17 (25.8 percent), 21 (31.8 percent) and 29 isolates (43.9 percent), respectively. One isolate (1.5 percent) was babA2 positive, being the first isolate with this genotype described in Chile. Besides the babA2+ genotype this clinical isolate also presented cagA+ and vacAs1a which has been related with metaplasia or gastric cancer. Five isolates showed an ulcerogenic profile cagA+, vacAs1m1. Conclusions: The results presented indicate the prevalence of vacAs1m1 genotype among the clinical isolates analyzed, and a low frequency of babA2 genotype.
Subject(s)
Humans , Adhesins, Bacterial/genetics , Antigens, Bacterial/genetics , Bacterial Proteins/genetics , Gastrointestinal Diseases/microbiology , Helicobacter Infections/microbiology , Helicobacter pylori/genetics , Adhesins, Bacterial/isolation & purification , Antigens, Bacterial/analysis , Bacterial Proteins/analysis , Biopsy , Chile , Genetic Markers , Genotype , Helicobacter pylori/pathogenicity , Peptic Ulcer/microbiology , Polymerase Chain Reaction , Virulence/geneticsABSTRACT
BACKGROUND: Klebsiella pneumoniae is a pathogenic bacterium frequently isolated from nosocomial samples, specially the subspecie pneunonlae, with extensive antibiolic resistance profiles, including third generation cepbhalosporiis, aminoglycosides and quinolones. This is specially true for those strains producing extended spectrum beta lactamases (ESBL). AIM: To investigate the susceptibility to gentamicin, amikacin and ciprofloxacin and the presence of some aminogloycoside modifying enzyme (AMEs) among nosocomial strains of K pneumoniae subspecie pneumoniae producing ESBL. MATERIAL AND METHODS: The antibiotic resistant patterns and the level of resistance (minimal inhibitory concentration, MIC) of 100 strains, isoklted from sel ,eal bospitals of dcifferent Chilean cities, were deterl,in,ed. Tbe presence of some aminoglycosides modifying enzyme (AMEs) was investigated by PCR. RESULTS: Sixty five percent of strains were resistant to gentamicin, 47% were resistant to amikacin, and 29% were resistant to ciprofloxacin. The most frequent AMEs genes detected were the aac(6')-Ib gene (6'N-Acetyltransferase type Ib enzyme) in 69% of strains, conferring resistance to amikacin, kanamycin, tobramycin, and nieoniycin, and the gene aac(3)-IIa (3-Acetyltransferase type 3-IIa enzyme), in 36% of strains, conferring resistance to gentamlicin. CONCLUSIONS: Among nosocomial strains of K pneumoniae subspecie pneumoniae isolaterd from Chilean hospitals, there is an association between the production of ESBL and the resistance to others antimicrobial agents, especially aminoglycosides. Nevertheless, 71% of isolates are susceptible to ciprofloxacin.