Presence of STa, STb and LT enterotoxin genes in Klebsiella strains isolated in different hospitals from gastrointestinal tracts

Abstract number: 1733_636

Maczyñska B., Kasprzykowska U., Zychowicz A., Przondo-Mordarska A., Bartoszewicz M., Smutnicka D.

Objectives:Klebsiella infections pose a significant problem, especially in paediatric wards where they can cause various nosocomial infections, such as serious diarrhoea in children and infants. Due to the fact that the microbes can also constitute normal flora of the alimentary canal, the key factor in considering them as an aetiological factor in diarrhoea is the determination of the presence of heat-stable and heat-labile enterotoxins. Therefore, the purpose of the paper was to investigate the genetic basis of the expression of enterotoxins (STa, STb and LT) among the selected strains isolated from diarrhoea cases in the hospitalised children. Because enterotoxin genes are encoded on the plasmids, which facilitates their transmission and spreading in nosocomial strains of Enterobacteriaceae, the paper also aimed to determine the frequency of occurrence of these genes in the Klebsiella species isolated in various clinical centres in Poland.

Methods: The research included 61 clinical Klebsiella strains isolated from faeces samples taken from children with diarrhoea symptoms hospitalised in various paediatric wards. Klebsiella strains not originating from diarrhoea cases but isolated from the blood and respiratory tract of hospitalised patients served as a control group. The presence of genes encoding ST and LT enterotoxins was detected using the PCR method with primers designed for sta, stb and lth genes described for E. coli.

Results: Research conducted indicates that in the plasmid DNA of the majority (85%) of Klebsiella strains isolated from diarrhoea cases, enterotoxin-encoding genes (sta, stb, lth) were detected. The 43% of the strains had genes for one enterotoxin, 39% genes for two endotoxins and 3% of strains showed the presence of three genes (sta, stb, lth). In the Klebsiella strains isolated from blood and the respiratory tract (negative controls), no sta, stb or lth genes were found.

Conclusions: The presence of enterotoxin-encoding genes have very important significance in diagnosing of aetiological agent of children diarrhoea. A direct correlation was shown between the frequency of individual gene detection and the clinical centre in which the given strain was isolated. Detection of enterotoxin-encoding genes in Klebsiella using the PCR method was regarded as useful in routine diagnosing of Klebsiella related diarrhoea cases.

Session Details

Date: 31/03/2007
Time: 00:00-00:00
Session name: European Society of Clinical Microbiology and Infectious Diseases
Location: ICC, Munich, Germany
Presentation type:
Back to top