Abstract 1587
Poster Session II, Sunday, 5/2 (poster 126)
Malassezia pachydermatis (M..P.) is a nonobligatory lipophilic yeast which has emerged as a nosocomial pathogen in a number of outbreaks in neonatal intensive care units. Understanding epidemiology of colonization may help limiting nosocomial outbreaks. The present study was designed to assess risk factors for colonization in infants <1.8kg and for fungemia in colonized infants. During an epidemic of M.P. (Jan-Sept 1998), a point-prevalence survey was done on March 14, 1998 by obtaining cultures from inguinal sites in all infants. Between end of March and the end of epidemics, cultures from <1.8kg infants were obtained from 4 sites (oropharynx, inguinal, rectum and endotracheal tube) at admission, weekly up to 4 weeks. Cultures were obtained by using premoistened sterile swabs and plating onto Sabourad dextrose agar without olive oil. M.P. was identified based on morphological and growth characteristics. On March 14, 1998, 11/35 (31%) patients were colonized with M.P.; these patients had longer duration of NICU stay, of IV fluid administration including parenteral nutrition and intralipid, central line and antibiotic therapy than non-colonized infants (p<0.05, Student t test). During the epidemics, we observed 15 cases of blood borne M.P. in patients <1.8kg. Colonization was documented at a mean age of 10±7 days (mean±SD) and fungemia at 31±12 days, i.e., 21±5 days after colonization. Sensitivity of various sites to detect M.P. were inguinal (87%), oropharynx(55%), rectum (35%) and endotracheal tube (8%). All colonized infants would have been detected by culturing the inguinal area and the oropharynx. Colonization at the inguinal area persisted longer. Among total of 34 infants <1.8kg, 31(92%) remained colonized during 4-week period. Of those who were colonized, 10/31(32%) developed fungemia and 21/31(68%) remained asymptomatic. All 10 fungemic infants were colonized (mostly at the inguinal site). The risk factors for fungemia included duration of umbilical artery catherer days, of percutaneous central line days and of intralipid days (p<0.05, multiple logistic regression analysis). The epidemic was eradicated after reinforcing handwashing, administering antifungal cream, cohorting and limiting invasive procedures.
