VALUE AND LIMITS OF YEASTS SURVEILLANCE IN INTENSIVE-CARE PATIENTS

Objective. The present study was designed to investigate the frequency and the distribution of yeasts in patients from the Intensive Care Un it (ICU) and to determine their clinical importance. Additionally, sev eral yeast identification technique were compared in order to find out the most appropriate system for the routine laboratory. Patients and methods. Between August 1, 1994 and April 1, 1995 mycological follow-u p were performed in 100 patients from the post surgical and in 26 pati ents from the neurological Intensive Care Unit. Tracheal and bronchial aspirate as well as urine samples obtained twice a week were cultured after dilution on Sabouraud agar at 30 degrees C. Following methods f or differentiation of the isolated yeast species were performed: germ tube test, microscopy on rice tween agar; Albicans ID agar, CHROMagar Candida, Fongiscreen 4H, API 20C Aux and Auxacolor identification pane ls. Results. Yeasts were found in 61.1 % of all patients, more frequen tly in men (68.3 %) than in women (47.7 %). The colonisation rate with Candida species was higher in patients undergoing an abdominal operat ion (72.4 %) than in those after an operation of the thorax (58.7 %). The quantitative analysis of yeasts revealed fluctuating and only mode rate numbers of colonies (< 10(6)/ml). During the study period no case of deep mycosis could be ascertained. The 101 strains recovered were distributed among 11 species, mainly C.albicans (48.5 %), C.(Torulopsi s) glabrata (26.7 %), C. tropicalis (10.9 %) and C. kefyr (2.9 %). C. albicans could be easily identified by germ tube test or by Albicans I D agar. With Fongiscreen 4H rapid diagnosis may be achieved, however o nly for the four main species. C. glabrata was difficult to distinguis h from other species on CHROMagar Candida. Compared with API 20C Aux, Auxacolor appeared as effective but more rapid, permitting the identif ication of a wide spectrum of yeasts mostly within 24 h. Conclusions. Our results suggest that patients from Intensive Care Units without ne utropenia are often colonized with Candida species but present rarely severe fungal infections. For the identification of these yeasts, the use of Albicans ID agar followed by Auxacolor seem to be a satisfying procedure for the routine laboratory.