A 48 year old man was admitted to the intensive care unit with septicaemic shock associated with febrile jaundice and anuric renal failure. Within hours, he developed cardiogenic shock with multi-organ failure due to an acute myocarditis refractory to catecholamines and requiring intra-aortic balloon pumping. The diagnosis was an ictero-haemorrhagic leptospirosis, the outcome of which was finally favourable. Myocarditis is an underestimated complication of leptospirosis because it is often symptomless. The main signs are arrhythmias, conduction defects and ST-T wave abnormalities which have little clinical expression. The disease may progress and is sometimes fatal. Leptospirosis myocarditis should therefore be carefully considered because of its potential severity and its reversibility with appropriate antibiotic therapy and also the necessity of initial management in a specific infrastructure.