Infective endocarditis secondary to intravenous Subutex abuse

Subutex (buprenophine) was approved by the Health Science Authority of Singapore for heroin detoxification in 2002. The number of heroin addicts has decreased in Singapore since the introduction of Subutex. However, Subutex abuse and its associated complications became arising medical problems. We report the management of a series of infective endocarditis cases secondary to Subutex abuse.

We identified 12 cases of infective endocarditis in former heroin addicts treated with Subutex from August 2005 to April 2006. All patients were interviewed by the research coordinator and prospectively followed-up for two years.

The treatment period of Subutex endocarditis was often prolonged with a mean hospitalisation stay of 48 days, with 3.8 days in the intensive care unit. Multiple medical complications were noted. Staphylococcus aureus septicaemia accounted for 92 percent of cases. Mortality rate was 42 percent. Failure rate of medical therapy alone was common. 25 percent underwent open heart valve surgery. All patients were subsidised. Mean hospitalisation expenses was S$31,218.

Subutex endocarditis causes significant morbidity and mortality. It imposes a heavy medical and financial burden to the patient and society. Multidisciplinary treatment involving cardiologists, infectious disease physicians, psychiatrists, surgeons, medical counsellors and social workers is required to manage these patients.