PROPHYLAXIS AGAINST MYCOSES IN GRANULOCYT OPENIC PATIENTS

During the last years, the proportion of cancer patients who develop s ystemic fungal infections has increased steadily. These infections are characterised by high mortality, especially in patients with persiste nt granulocytopenia and in those receiving allogeneic bone marrow tran splants. The most important pathogens in neutropenic patients are Cand ida and Aspergillus spp. Usually, Candida infections arise from overgr owth in the gastrointestinal tract, while Aspergillus infections are a cquired by inhalation of spores. Prophylaxis of systemic fungal infect ions seems mandatory since optimal strategies for diagnosis and treatm ent of these infections are lacking. Treatment with the non-absorbable polyenes nystatin and amphotericin B is useful for prophylaxis of sup erficial fungal infections, provided that compliance of the patients i s optimal. The imidazoles ketoconazole and miconazole can reduce the i ncidence of superficial fungal infections, but there are conflicting d ata regarding their value for prevention of systemic mycoses. There ar e several studies indicating that prophylactic use of fluconazole redu ces the incidence of mucosal and systemic fungal infections, especiall y in patients receiving allogeneic bone marrow transplants. Fluconazol e shows reduced activity against several Non-albicans spp. and is not active against Aspergillus spp. Itraconazole has in vitro and in vivo activity against several Aspergillus spp. but high serum and tissue le vels are necessary. However, bioavailability of itraconazole is reduce d in patients with raised gastric pH and no i.v. formulation is availa ble. Although there is some evidence for its prophylactic activity aga inst Aspergillus infections in neutropenic patients, more studies are necessary to confirm these findings. Intravenous amphotericin B cannot be recommended for routine prophylactic use because of its toxicity. Ongoing studies investigate the value of inhaled amphotericin B for pr ophylaxis of fungal pneumonia. The liposomal amphotericin B preparatio n cannot be used routinely for prophylaxis because of its high cost. A t present, there is no antifungal agent that can be recommended for pr ophylaxis of all fungal infections in neutropenic patients. Possibly, the use of haemato-poetic growth factors like G-CSF With its ability t o accelerate recovery of the neutrophils will be useful for prophylaxi s of fungal infections in neutropenic cancer patients.