Current antibiogram and clonal relatedness among drug-resistant Salmonella enterica serovar Typhi in Northern India

In view of the changing sensitivity pattern of Salmonella, this study was carried out to investigate the current antibiogram and clonal relatedness among the drug-resistant Salmonella enterica serovar Typhi in Northern India.

Re-emergence in the sensitivity to chloramphenicol and cotrimoxazole with increase in the resistance to various quinolones has been observed. The efficacy of nalidixic acid resistance to be used as a marker for decrease in sensitivity to ciprofloxacin may vary. Clonal differences on the basis of amplification of repetitive elements (rep-PCR) were found in the two different areas within the same region.

The present study creates a paramount baseline for rationalizing the judicious use of quinolones and re-examine the use of chloramphenicol and cotrimoxazole. Molecular analysis of clinical Salmonella isolates depicts the clonal expansion of the isolates that may serve as a reference to which newer outbreak strains can be compared. rep-PCR techniques may be useful in molecular discrimination of isolates for better understanding of the Salmonella epidemiology and as a basis for development of rational control strategies.