Risks involved in selective decontamination in immunocompromised patients

Selective oral and systemic decontamination are widely discussed when it comes to the prophylaxis of bacterial and fungal infections in immunocompromised patients. The number of such patients is clearly rising due to the aggressiveness of modern medicine. Host defence is based on a variety of factors including the barrier function of mucosal surfaces as well as the phagocytic system provided by the blood. It seems helpful to distinguish between three different stages of immunodeficiency: "Minor immunodeficiency", "immunodeficiency" (in a stricter sense), "major immunodeficiency". When it comes to the choice of measures to be taken to protect the host, it is not only needed to consider the microbes already present but also the present state of defence mechanisms. When invasive fungal infections in particular have to be prevented, several drugs have to be discussed. As conventional antifungals have not met all expectations there is clear need for new drugs such as itraconazole.