Effect of bismuth hydroxide gel on Verocytotoxin-producing Escherichia coli

ETCHEVERRÍA, ANALÍA I.; ARROYO, GUILLERMO H.; GAGUINE, L; PADOLA, NORA L.

Boston

Simposio; 9 th Internacional Symposium on Shiga Toxin (Verocytotoxin) Producing Escherichia coli Infections (VTEC 2015).; 2015

VTEC 2105

Escherichia coli (VTEC)are a group of pathogens known because of its importance in public health. They can cause diarrhea, hemorrhagic colitis, and uremic hemolytic syndrome mainly in children. Cattle are one of the main reservoirs of VTEC, they carry these pathogens into their gastrointestinal tract (GIT), and shed them with feces, contaminating the environment. At slaughter, carcasses can become contaminatedifoutput ofgastrointestinal contents, thus VTEC would enter the food chain. Some approaches have been made in the control of the reservoir at farm level to reduce the carrying of VTEC by bovine in an attempt to limit potential contamination of meat. As the bismuth hydroxide gel is widely used in humans for the treatment of diarrhea, the aim of this work was to investigate if the use of bismuth hydroxide gel has any some effect on the survival of VTEC in vitro. Methods:VTEC O157, O145, 026 and O103 were cultured in 10mL of LB broth for 18h at 37°C to reach a final concentration of 103ufc/ml. Then, it was added 1 ml of bismuth hydroxide gel (final concentration 4.2 mg/ml). At different times,(0, 1, 2, 4, 6h) an aliquot was plated onto MacConkey agar and incubated for 18h at 37 °C for colony counts. Results and discussion: The effect of bismuth hydroxide gel was evaluated by the number of colonies obtained at different times. In VTEC O26, O103 and O157 it was observed a significant reduction in colony number during the first 6h. The growth of VTEC O145 was not affected at any time. Implications:Theseresults allow us to speculate on theuse of the bismuth hydroxide gel as a tool for controlling VTEC in cattle before slaughter.