Nystatin prophylaxis of fungal colonization and infection in granulocytopenic patients: correlation of colonization and clinical outcome.

Nystatin, one million units every four hours, was prospectively studied as a prophylactic antifungal agent in 164 neutropenic patients who were not initially colonized by fungi: 104 received nystatin and 60 served as controls. Fungal colonization occurred in 68/104 (65%) nystatin recipients and in 43/60 (71%) controls. However, nystatin significantly reduced multiple body site colonization and persistent oropharyngeal colonization. Despite these alterations in colonization profile, 16/104 (15%) nystatin recipients developed disseminated fungal infections, as compared to 5/60 (8%) control patients (0.5 greater than p greater than 0.1, N.S). Differences in the clinical course of colonized and non-colonized patients were observed. Eighteen of 111 (16%) colonized patients had afebrile clinical courses as compared to 16/53 (30%) non-colonized patients (p less than 0.05). Twenty-nine of 93 (31%) febrile episodes in colonized patients failed to respond to empiric antibiotic therapy as compared to 3/37 (8%) episodes in non-colonized patients (p less than 0.01). Disseminated fungal infections were diagnosed in 19/111 (17%) of colonized patients, as compared to 1/53 (2%) non-colonized patients (p less than 0.02). We conclude that colonized patients are more likely to develop febrile clinical courses, to fail to respond to empiric antibiotic therapy, and to develop disseminated fungal infection. Nystatin altered colonization patterns but did not prevent disseminated fungal infection.