Invasive fungal infection in the immunosuppressed host.

Immunosuppression, whether arising as a consequence of disease (haematopoietic and lymphoreticular malignancies) or therapy (against hemograft rejection or malignancy results in a higher than normal incidence of invasive fungal infections such as candidiasis, aspergillosis, mucormycosis and cryptococcosis. Normal host defense mechanisms, both immunologic and non-immunologic, are not fully functional and may contribute to the pathogenesis of these diseases.Candida, normally a superficial colonizer, may invade the gastrointestinal, respiratory or urinary tracts. Aspergillus and mucor species may cause hemorrhagic or necrotising pneumonias and secondarily spread to the brain. Cryptococcus may infect the meninges in the appropriate host. Therapeutics for these diseases is limited. Amphotericin B may alter the course of any of the four diseases. Fluorocystosine has found some use in the treatment of candidiasis and cryptococcosis.