Purpose: The present study was performed to assess the current susceptibility pattern of blood isolates of
Salmonella
spp from a super specialty hospital in North India against nalidixic acid, ciprofloxacin and azithromycin and compare the
in vitro and
in vivo response against azithromycin.
Materials and Methods: We evaluated the minimum inhibitory concentration′s (MIC′s) of 107 blood isolates of
Salmonella spp against nalidixic acid, azithromycin and ciprofloxacin and correlated
in vitro and
in vivo response of azithromycin from the treatment and discharge summaries from the Hospital Information System (HIS) software.
Results: Among the 107 isolates evaluated, 94 (87.8%) were nalidixic acid-resistant (NAR)
Salmonella and 36 were resistant to azithromycin by MIC testing. The MIC
90 value for azithromycin was 24 μg/mL. Among the 57 treatment histories evaluated using the HIS software, 19 (33%) patients had documented clinical non-response to azithromycin which required change of therapy.
Conclusions: The present study observed a higher MIC
90 values for azithromycin compared to
Salmonella isolates from Western studies. There was also a documented clinical non-response against azithromycin. The
in vitro and
in vivo findings in this study suggest a guarded use of azithromycin for cases of enteric fever in India. The study also augments the reversal of resistance pattern in favour of chloramphenicol, ampicillin and trimethoprim - sulfamethoxazole.
