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Background & objectives: Bacillus cereus is one of the pathogens responsible for human diarrhoea, mainly due to consumption of contaminated food. The present study was undertaken to determine the occurrence of B. cereus among diarrhoeal patients and its phenotypic and genetic characteristics that determine the virulence and clonal features. Methods: Stool specimens were collected for two years from acute diarrhoeal patients attending the two referral hospitals in Kolkata. Presence of virulence genes in B. cereus was determined by PCR. Clonality was assessed by pulsed-field gel analysis (PFGE) by restriction digestion with SmaI and NotI enzymes. Enterotoxins were detected by haemolysin assay and using BCET-RPLA kit. Invasion assay was done on Hep-2 cell line. Antimicrobial susceptibility was tested by disc diffusion method. Results: B. cereus was identified in 54 (3.5%) of the 1536 diarrhoeal cases studied. Majority of the isolates were susceptible to many antibiotics but showed resistant to amoxyclav and cephalosporins. Six genes covering the two different enterotoxic complexes determining the pathogenicity of B. cereus have been characterized by PCR. The nhe genes were detected in a higher proportion than hbl. Except in two, clonal diversity was noticed among 21 B. cereus isolates. Haemolytic enterotoxin was detected in 76 per cent of the isolates. Majority of the isolates (67%) produced in vitro enterotoxin (BCET) confirming its involvement in the infection. Interpretation & conclusions: Though the presence of B. cereus was not high in patients with diarrhoea, several virulence factors confirm their association with diarrhoea. Distinct clonality was identified in majority of the isolates indicating their origin from different sources. [ABSTRACT FROM AUTHOR]

Introduction: Infections caused by multidrug resistant bacteria act as a risk factor for mortality in burns patients. So keeping in view the crucial importance of reliable therapeutic decisions of multidrug resistance bacteria and role of hospital environment in bacteria colonization, our study is based on the evaluation of distribution of Pseudomonas sp. and Bacillus sp. in burn patients and burn ward environment., Methods: The present prospective analysis was conducted on the patients undergoing treatment in the Burn ward of Pt. B.D. Sharma University of Health Sciences, Rohtak, Haryana, during the period of January 2012 to March 2013. The multidrug resistant bacteria were characterized by following the CLSI guidelines. Molecular identification isolates were done by amplifying and sequencing 16S rDNA., Results: In our study out of 510 samples of 280 burn patients, 263 samples were observed sterile and bacterial isolates were obtained from 247 samples. In burn patients out of 247 samples 43 MDR strains, and in burn ward out of 60 samples 4 MDR strain were observed. After 16S rDNA amplification of MDR isolates the prevalent bacterium was belonged to the genus Bacillus (8 species; 26 isolates) followed by genus Pseudomonas (5 species; 17 isolates). The burn ward environment isolates were Pseudomonas aeruginosa, Pseudomonas stutzeri, Bacillus cereus and Acinetobacter baumanii., Conclusion: The major finding of our study is the predominance of B. cereus followed by P. aeruginosa in burn patients of Pt. B.D. Sharma University of Health Sciences, Rohtak, Haryana. While considering the role of hospital environment, no direct role of environmental isolates was observed in transfer of bacterial infection., (Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.)