Sensibilidad antimicrobiana de los uropatógenos y resultados del tratamiento antibiótico de las infecciones urinarias en atención primaria

BACKGROUND AND OBJECTIVE. An increase in the resistance to antimicrobial agents among bacteria causing urinary tract infections (UTI) has been reported. The aim of this study was to relate uropathogen susceptibility to prescribed antibiotics for UTI to the clinical outcome after therapy in primary health care patients. METHODS. A prospective longitudinal study, including 118 women diagnosed with UTI was carried out in primary health care centers. The results of urine culture, antimicrobial susceptibility testing and the prescribed antibiotic treatment were recorded. The patients' clinical outcome and the results of follow-up urine cultures after therapy were also recorded. RESULTS. The uropathogens isolated were susceptible to the prescribed antibiotic in 86% of patients. Clinical improvement at two weeks was observed in 91% of patients with bacteria sensitive to the prescribed antibiotics and 7% of patients with resistant bacteria (P = 0.06). At 4-6 weeks, there were no clinical symptoms in 88% of patients with sensitive bacteria and 71% of patients with resistant bacteria (p = 0.23). In follow-up urine cultures, bacteria had been eradicated in 74% of patients with sensitive bacteria and 50% with resistant bacteria (p = 0.34). CONCLUSIONS. The majority of women diagnosed with UTI in primary health care had uropathogens sensitive to the prescribed antibiotic and treatment was effective at short term in this study. The results of antimicrobial susceptibility testing were not always related to the clinical outcome; bacterial resistance may overestimate the risk of therapeutic failure in UTI.