Community acquired urinary tract infection: etiology and bacterial susceptibility

Purpose: Urinary tract infections (UTI) are one of the,most common infectious diseases diagnosed. UTI account for a large proportion of antibacterial drug consumption and have large socio-economic impacts. Since the majority of the treatments begins or is done completely empirically, the knowledge of the organisms, their epidemiological characteristics and their antibacterial susceptibility that may vary with time is mandatory. Objetive: The aim of this study was to report the prevalence of uropathogens and their antibiotic susceptibility of the community acquired UTI diagnosed in our institution and to provide a national data. Methods: We analyzed retrospectively the results of urine cultures of 402 patients that had community acquired urinary tract infection in the year of 2003. Results: The mean age of the patients in this study was 45.34 t 23.56 (SD) years. There were 242 (60.2 percent) females and 160 (39.8 percent) males. The most conunonly isolated organism was Escherichia coli (58 percent). Klebsiella sp. (8.4 percent).and Enterococcus sp.(7.9 percent) were reported as the next most common organisms. Of all bacteria isolated from community acquired UTI, only 37 percent were sensitive to ampicillin, 51 percent to cefalothin and 52 percent to trimethoprim/sulfamethoxazole. The highest levels of susceptibility were to imipenem (96 percent), ceftriaxone (90 percent), amikacin (90 percent), gentamicin (88 percent), levofloxacin (86 percent), ciprofloxacin (73 percent), nitrofurantoin (77 percent) and norfloxacin (75 percent). Conclusions: Gram-negative agents are the most common cause of UTI. Fluoroquinolones remains the choice among the orally administered antibiotics, followed by nitrofurantoin, second and third generation cephalosporins. For severe disease that require parenteral antibiotics the choice should be aminoglycosides, third generation cephalosporins, fluoroquinolones or imipenem, which were the most effective.

Prevalence and bacterial susceptibility of hospital acquired urinary tract infection

Purpose: Urinary tract infection is the most common nosocomially acquired infection. It is important to know the etiology and antibiotic susceptibility infectious agents to guide the initial empirical treatment. Objective: To determine the prevalence of bacterial strains and their antibiotic susceptibility in nosocomially ácquired urinary tract infection in a university hospital between January and June 2003. Methods: We analyzed the data of 188 patients with positive urine culture (= 105 colony-forming unitslmL) following a period of 48 hours after admission. Results: Half of patients were male. Mean age was 50.26 ± 22.7 (SD), range 3 months to 88 years. Gram-negative bacteria were the agent in approximately 80 percent of cases. The most common pathogens were E. coli (26 percent), Klebsiella sp. (15 percent), P. aeruginosa (15 percent) and Enterococcus sp. (11 percent). The overall bacteria susceptibility showed that the pathogens were more sensible to imipenem (83 percent), second or third generation cephalosporin and aminoglycosides; and were highly resistant to ampicillin (27 percent) and cefalothin (30 percetn). It is important to note the low susceptibility to ciprofloxacin (42 percent) and norfloxacin (43 percent). Conclusion: This study suggests that if one can not wait the results of urine culture, the best choices to begin empiric treatment are imipenem, second or third generation cephalosporin and aminoglycosides. Cefalothin and ampicillin are quite ineffective to treat these infections.