Invasive Fungal Infection in Febrile Patients with Hematologic Malignancies Undergoing Chemotherapy in Iran

Background: Patients with hematological malignancies undergoing cytotoxic chemotherapy are susceptible to develop invasive fungal infections particularly Aspergillus and Candida spp. Early detection of these infections is required to start immediate antifungal therapy and increase the survival of these patients. Method: Our study included consecutive patients of any age with hematologic malignancies who were hospitalized to receive chemotherapy and suffer from persistent fever (rectal temperature >38.5°C) for more than 5 days despite receiving broad-spectrum antibiotics. A whole blood sample was taken and sent for blood culture. PCR was also conducted for Aspergillus and Candida species. Results: One hundred and two patients were investigated according to the inclusion criteria. The most common hematologic malignancy was AML affecting 38 patients (37.2%). Six patients were diagnosed with invasive fungal infections (A. fumigatus n=3, C. albicans n=2, A. flavus n=1) by PCR (5.8%) while blood culture showed fungus only in 1 patient. Three more cases were known as probable IFI since they responded to antifungal therapy but the PCR result was negative for them. AML was the most prevalent malignancy in IFI patients (83.3%) and odds ratio for severing neutropenia was 21.5. Odds for each of the baseline characteristics of patients including gender, age>60, diabetes mellitus, previous IFI, history of using more than 3 antibiotics, antifungal prophylaxis, episodes of chemotherapy> 8 and chemotherapy regimen of daunarubicin+cytarabine were calculated. Conclusion: We found that multiplex real-time PCR assay is more accurate than blood culture in detecting fungal species and the results are prepared sooner. Among all factors, the only type of cancer (AML) and severe neutropenia, were found to be risk factors for the development of fungal infections in all hematologic cancer patients and previous IFI was a risk factor only AML patients.