Oral nystatin prophylaxis of Candida spp. colonization in ventilated critically ill patients

Colonization of multiple body sites is a leading risk factor for Candida spp. infection in intensive care unit (ICU) patients. We evaluated whether oral nystatin prophylaxis reduces Candida spp. colonization in ventilated ICU patients.

Prospective, randomized, open-label study with blinded assessment of the objective primary evaluation criterion in the medical-surgical ICU of a teaching hospital.

The study included 98 consecutive patients mechanically ventilated for at least 48 h (mean age 58+/-19 years; mean SAPS II 40+/-11), assigned to either treatment group (n=51) or control group (n=47). Study groups were comparable for age, SAPS II, reason for admission, and immune status.

Patients were randomized to receive oral nystatin (treatment group; 3x10(6) U per day) or no nystatin (control group). Multiple body sites (trachea, stomach, rectum, urine, groin, and blood) were tested for Candida spp. on admission and then every 3 days by mycologists blinded to group assignment, and the colonization index was determined.

Colonization by Candida spp. developed in 25% of controls but in none of the treated patients. In multivariate analysis, the absence of nystatin prophylaxis and ICU length of stay were independently associated with Candida spp. colonization. No invasive candidiasis was diagnosed in either study group.

Oral nystatin prophylaxis efficiently prevented Candida spp. colonization in ICU patients at low risk of developing invasive candidiasis. Further studies are needed to determine whether this strategy remains efficient in reducing Candida spp. infections in higher risk ICU patients.