Epidemiological Characteristics of Fatal Candida krusei Fungemia in Immunocompromised Febrile Neutropenic Children In early 1990s, fluconazole was introduced as a prophy- lactic antifungal agent after stem cell transplantation (SCT). At the same time, Candida krusei emerged as a chief fungal pathogen among the patients with SCT [1, 2]. In our SCT center, which has a 15-bed capacity unit dedicated for children with malignant diseases and 5-bed unit for SCT patients, low-dose fluconazole is routinely included in the posttransplant prophylaxis regimen (starting at day 7). In recent years, we observed mortality due to fungal sepsis in patients undergoing allogenic SCT and chemotherapy. Here, we report the characteristics of the patients having mortal C. krusei fungemia and the molecular typing results of the C. krusei strains in order to develop more effective policies for treatment and pre- vention of fungal infections. The febrile neutropenic episodes of the 47 children (median age: 9.13 ± 4.73 years) were prospectively eval- uated from March 2001 to January 2003. For each patient, daily leukocyte counts and body temperatures were measured. Fever was defined as a single oral temperature of ‡ 38.3°C or a temperature of ‡ 38.0°C for ‡ 1 h. Neu- tropenia was defined as a neutrophil count of < 500 cells/ mm 3 , or a count of < 1,000 cells/mm 3 with a predicted decrease to < 500 cells/mm 3 (Guidelines from the Infec- tious Disease Society of America, 1997). Patients who had both fever and neutropenia were recognized as febrile neutropenic. Nine patients developed severe fungal infection during neutropenia. Three of those having bloodstream infection with the C. krusei were analyzed in detail, in this study. Surveillance cultures were taken from blood, throat, stool, urine and catheter exit sites of the patients in the SCT unit when they had febrile episode and/or weekly on a routine basis. Automated blood culture system (Becton Dickinson, pediatric vials, USA) and BACTEC MYCO/F LYTIC (Becton Dickinson) were used for blood cultures. To search exogenous sources of C. krusei sepsis, 51 specimens from the hands of 32 health care workers (9 doctors, 11 nurses, 4 laboratory workers, and 8 cleaning staff) and 19 environmental swabs from commonly used areas around the patients (nurse desk, room and toilet doors, refrigerator doors, telephones, etc) were analyzed. The isolated yeasts were identified by using API 20 C AUX (BioMerieux, France) kits. E test was used for the antifungal susceptibility. Molecular typing of the nine C. krusei strains of the three patients (three blood, two stool, one urine, one throat, one vagina, and one sputum iso- lates) was performed by pulsed field gel electrophoresis (PFGE) following the protocol described previously [3]. A total of 156 febrile episodes were recorded in the 47 patients within the 312 febrile neutropenic days. Bacteria were isolated in 28 (52%) and fungi in 26 (48%) of the 54 clinical specimens. It was noted that the patients with prolonged and deep neutropenia (hematological malig- nancy patients) are under an increased risk for fungal infections [1, 4, 5]. In agreement with these findings, we observed systemic fungal infections with high mortality in recent years. Of the 47 patients with febrile neutropenia, 14 had fungal isolation from various body sites and 9 (19%) died due to fungal infection. Eight of these fatal cases had non-Candida albicans infection (Table 1). Dis- tribution of Candida spp. among the five non-fatal cases was as follows: C. krusei (1), C. kefyr (1), C. albicans (2), C. famata (1). In an Italian tertiary hospital, it was found that 60% of the candidemia episodes were related to non- albicans Candida and high mortality rates were observed particularly for hematological (71%) and transplant patients (50%) [6]. In another tertiary care hospital in Infection 2008; 36: 88–91 DOI 10.1007/s15010-007-6246-1 H. Agirbasli Our-Children Leukemia Foundation, Pediatric Blood Diseases Hospital, Istanbul, Turkey B. Otlu Dept. of Clinical Microbiology, Molecular Microbiology Section, Inonu University, Faculty of Medicine, Malatya, Turkey H. Bilgen Istanbul University Cerrahpas ¸ a Medical Faculty Blood Center, Istanbul, Turkey R. Durmaz (corresponding author) Dept. of Clinical Microbiology, Molecular Microbiology Section, Inonu University, Faculty of Medicine, Malatya, Turkey; Phone: (+90/422) 341-0126, Fax: -0036, e-mail: rdurmaz@inonu.edu.tr G. Gedikoglu Our-Children Leukemia Foundation, Pediatric Blood Diseases Hospital, Istanbul, Turkey Received: September 5, 2006 Æ Revision accepted: August 7, 2007 Published online: December 14, 2007 Infection Correspondence 88 Infection 36 Æ 2008 Æ No. 1 Ó URBAN &VOGEL