We report a case of acute myocarditis associated with pericarditis in a patient hospitalized for urinary tract infection due to Escherichia coli. To the best of our knowledge, there are no prior descriptions of acute myocarditis associated with pericarditis during Escherichia coli infections in the absence of sepsis. In our patient, myocardial damage has been accurately documented by electrocardiography, echocardiography and magnetic resonance imaging. Inclusion of magnetic resonance imaging allows detection of myocardial inflammatory lesions that otherwise would have remained undiagnosed. The basic mechanisms of myocardial damage during Escherichia coli infection are unclear. Endotoxins might cause inflammatory reactions in the myocardium leading to myocyte damage. After initiation of antibiotic therapy, there was a rapid improvement of contractile function, with concomitant normalization of clinical and biochemical abnormalities. We discussed our findings in the context of the limited information available from the literature.