Background: Escherichia coli O157:H7 is a foodborne pathogen causing haemorrhagic colitis, which is sometimes complicated by haemolytic uraemic syndrome or thrombotic thrombocytopenic purpura.
Aim: To review the available evidence regarding the question of whether antibiotics are effective or harmful for the treatment of patients infected with E. coli O157:H7 infection.
Methods: We searched in the PubMed for relevant laboratory and clinical studies published between 1982 and 2005.
Results: In vitro studies have shown that most E. coli O157:H7 isolates are susceptible to various antibiotics, although certain antibiotics, especially at sublethal concentrations, have been found to increase the release of Shiga-like toxins, which have been associated with the development of haemolytic uraemic syndrome/thrombotic thrombocytopenic purpura in humans. No clinical studies have indicated that antibiotics are effective in reducing the duration of E. coli O157:H7 infection or the duration of diarrhoea or bloody diarrhoea specifically, while a few studies have supported that some antibiotics, especially quinolones and fosfomycin, may prevent the development of haemolytic uraemic syndrome or thrombotic thrombocytopenic purpura. On the other hand, there are some clinical studies that associate antibiotics with a higher risk for haemolytic uraemic syndrome and/or longer duration of diarrhoea, even with high mortality.
Conclusions: More randomized controlled trials are necessary in order to elucidate whether antibiotics are effective in reducing the morbidity and mortality of E. coli O157:H7 infection, rather than having a detrimental effect.