In-vitro activity of nitrofurantoin in enterococcus urinary tract infection.

OBJECTIVE To compare in-vitro antimicrobial susceptibility of nitrofurantoin against commonly used antimicrobials for the treatment of urinary tract infection caused by enterococci. METHODS A total of 144 enterococci (Enterococcus faecalis, n=130, Enterococcus faecium, n=14) isolated and confirmed by biochemical tests at the department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi, for a period of three years were included in the study. The antimicrobial susceptibility tests of isolated organisms were performed by standard disc diffusion method as recommended by NCCLS. In addition to nitrofurantoin (NIT), doxycycline (DOX), co-trimoxazole (COT), ampicillin (AMP), imipenem (IPM) and vancomycin (VAN) were used for antimicrobial susceptibility testing. RESULTS One hundred and twenty seven (88%) isolates of Enterococci were susceptible to NIT while 72% (n = 103) to AMP, 13% to COT, 11% to DOX, 91% to IPM and 99% to VAN. Among the strains resistant to AMP, COT, DOX, IPM and VAN, 50-88% were susceptible to NIT. CONCLUSION Nitrofurantoin is an effective antimicrobial in vitro and can be used for treatment of Enterococcus urinary tract infections.