Cyclosporin A is widely used in organ transplantation, preventing the rejection of multiple types of organ allografts. It is also being increasingly used as an immunosuppressive agent to treat various autoimmune diseases in patients refractory to more commonly used immunosuppressive therapy. Several trials are currently evaluating the utility of this drug associated with corticosteroids in the treatment of systemic lupus erythematosus. This case, describing a lethal septicaemia caused by Listeria monocytogenes in a patient receiving this treatment, seems to indicate that the use of these "cocktails" of immunosuppressive drugs should be particularly cautious to prevent fatal infectious complications.