Trends in the Antibiotic Resistance Patterns of Enteric Fever Isolates – a Three Year Report from a Tertiary Care Centre

Objectives: The incidence of multidrug resistant enteric fever is increasing alarmingly. This study was planned to determine the rate of isolation of Salmonella spp. and to compare the isolates for their epidemiological parameters and antimicrobial susceptibility patterns at our center. Methods: The study was conducted over a span of three years with a total of 8142, 8134, and 8114 blood culture samples processed for the years 2008, 2009, and 2010 respectively. The minimum inhibitory concentration (MIC) for ciprofloxacin and chloramphenicol was determined using an agar dilution method. The MIC for ciprofloxacin was also confirmed by Epsilon-test (E -test) strips. Results: Of the total 302 Salmonella spp. isolated, 257 were Salmonella enterica serotype Typhi (85.1%) and 45 (14.9%) were S. enterica serotype Paratyphi A. The majority of the isolates recovered were from the pediatric age group (54.6%) and males (60.6%). Complete susceptibility was observed to chloramphenicol, cefotaxime, ceftriaxone, and azithromycin over the last two years (2009 and 2010), with an increase in resistance to nalidixic acid (100%) and ciprofloxacin (13.6%). Conclusions: In our study, we found augmentation of resistance to nalidixic acid and fluoroquinolones and complete sensitivity to ceftriaxone along with reemergence of chloramphenicol sensitivity for Salmonella isolates. This report emphasises the necessity of continuous surveillance of antibiograms of enteric fever isolates in an area.

Salmonella-salmonellosis-rare presentations of a common pathogen

Salmonella are most commonly associated with gastroenteritis and enteric fever in humans. Occasionally, dissemination of bacilli throughout the body results in establishment of localized foci of persistent infection especially in patients with debilitating diseases and immunosuppressive states. Infection at various aberrant sites due to Salmonella has been reported relatively seldom. It has perfected the art of intracellular survival in niches from where they can cause myriad of effects. Six cases with Salmonella infection at unusual sites without any preexisting or underlying disease diagnosed over a period of two years are presented here. Salmonella etiology was not suspected in these patients and the diagnosis was made microbiologically only after culture isolation.