Three days after the end of a bout of diarrhoea of 3 days' duration, a 19-year-old patient developed severe nocturnal thoracic pain unresponsive to isosorbitol dinitrate. There were no abnormal findings on physical examination, except a sweaty skin. SGOT (38 U/l), creatinine kinase (291 U/l, CK-MB 29 U/l) and lactate dehydrogenase (246 U/l) were all elevated. The ECG showed ST segment elevations in leads I, II, III, aVF and V1-V6 as well as negative terminal T waves in I, II, aVL, AVF and V3-V6, changes suggesting peri- and myocarditis. The Widal test gave a raised antibody titre (1:800) against Yersinia enterocolitica serotype O:3. Seven days later the immunoblot test demonstrated antibodies against the same organism, which was finally isolated from stool after 11 days. Treatment consisted of ciprofloxacin (500 mg twice daily for 14 days). All symptoms, as well as the biochemical and ECG abnormalities, quickly improved. The patient was discharged free of symptoms after 34 days.
