Molecular Detection of Invasive Aspergillosis in Hematologic Malignancies P. Badiee, P. Kordbacheh, A. Alborzi, M. Ramzi, E. Shakiba Abstract Background: Aspergillus species are the most frequent causes of invasive mold infections in immunocompromised patients, particularly those who underwent chemotherapy for hematologic malignancies. The aim of this study was to determine the incidence and efficiency of the PCR-enzyme linked immunosorbent assay method (PCR-ELISA) for early detection of Aspergillus species in patients with hematologic malignancies. Patients and Methods: From 2004 to 2006, 194 patients with hematologic malignancies (who received chemother- apy) were evaluated for invasive aspergillosis (IA) in Shiraz, southern Iran. Ethylenediaminetetraacetic acid anticoagu- lant whole blood samples were collected prospectively once a week and stored at –20 °C until examination. All collected blood samples were assayed for the presence of the bands on ethidium bromide stained gel and for hybridization. Results: The female-to-male ratio was 61:133, the mean age of patients was 33.7 years, and mean of hospitaliza- tion period was 21.2 days. PCR-ELISA was positive in 14 (7.2%) patients who exhibited clinical and radiologic signs of IA. The etiologic agents were Aspergillus flavus (11 cases) and Aspergillus fumigatus (three cases). The mean time of positivity of PCR-ELISA in the blood before the appearance of clinical signs was 12.6 days. PCR was found to be the earliest indicator of IA preceding nonspecific clinical and radiologic findings. The sensitivity, specificity, positive, and negative predictive values of PCR-ELISA to detect DNA-specific for Aspergillus species in patients with proven and probable IA were 66%, 96%, 62.5%, and 97%, respectively. In case patients were treated with antifungal drugs, and the treatment was successful, fungal PCR assay became negative after 14 days and if the treatment failed, assay was positive until death. Conclusions: We demonstrated, in the present study, the incidence of IA in leukemic patients and the usefulness of molecular assay for early diagnosis and monitoring of the treatment of IA. Infection 2008; 36: 580–584 DOI 10.1007/s15010-008-7385-8 Introduction Invasive aspergillosis (IA) is a leading cause of infection among patients undergoing hematopoitic stem cell trans- plantation and treatment for hematologic malignancies [1]. Although many species are found within the genus, three species, namely, Aspergillus flavus, Aspergillus fumigatus and Aspergillus terreus are the most causative agents of IA. Certain species are associated with higher mortality and increased virulence and vary in their resis- tance to antifungal therapy; therefore the ability to diag- nose early and distinguish between the various clinically relevant Aspergillus species can have diagnostic value. The high mortality rate of IA is caused in part by difficulties in diagnosis at early stages of the disease and most IA is proved only at autopsy. Definitive diagnosis requires histopathologic evidence of deep tissue invasion or positive culture from sterile sites. The morphologic similarities of many filamentous fungi in tissues make the specific identification difficult [2, 3]. The detection of galactomannan antigen in serum by enzyme immunoassay has been an important adjunct in the diagnosis of IA. Although this test is promising as a screening tool, the effect on specificity of a newly intro- duced lower positive cutoff value is still under investiga- tion. Initial enthusiasm for the Aspergillus galactomannan test as a diagnostic tool must be tempered, as the sensi- tivity of the assay is lower than expected [4]. Sensitivity could be improved by lowering the proposed assay cutoff value in adults not receiving the immunosuppressant [4]. P. Badiee (corresponding author), A. Alborzi, E. Shakiba Prof. Alborzi Clinical Microbiology Research Center, Shiraz University of Medical Sciences, Nemazi Hospital, Zand Ave, Shiraz, Iran; Phone: (+98/711) 629-2021, Fax: -628-7071, e-mail: Badieep@yahoo.com P. Badiee, P. Kordbacheh Dept. of Medical Parasitology and Mycology, School of Public Health and Institute of Public Health Research, Tehran University of Medical Sciences, Tehran, Iran M. Ramzi Dept. of Hematology and Bone Marrow Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran Received: October 1, 2007 Æ Revision accepted: March 3, 2008 Published online: October 14, 2008 Infection Brief Report 580 Infection 36 Æ 2008 Æ No. 6 Ó URBAN &VOGEL