Abstract 1544Since myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) are more prevalent in the elderly, intensive chemotherapy is difficult. However, recent progress in supportive therapy, especially with anti-fungal agents, and diagnostic procedures for invasive fungal infection (IFI) such as β-D glucan (β-D), galactomannan antigen (GM) and computed tomography (CT), have resulted in dramatically enhanced safety of post-chemotherapy control of elderly patients.To evaluate the efficacy and safety of our diagnosis and treatment strategy for IFI, we examined 112 consecutive episodes in 110 patients who received remission induction therapy from December 15, 2009 to June 18, 2011, including new or recurrent patients with MDS related AML (MDS-AML) and those with AML without a history of invasive aspergillosis (IA). Diagnosis was MDS-AML in 88 episodes (relapse 18) and AML in 24 (M1 5,M2 9,M4 9,M6 1).The median age was 70 (range: 21–88).Remission induction therapy consisted of behenoyl-ara-C for 10 days and idarubicin for 4 days (For further details, please refer to 51st ASH abstract #1052; Taiichi Kyo et al). Patients were always admitted to a clean room until neutrophil recovery, and were routinely administered macrophage-colony stimulating factor (CSF) and granulocyte-CSF. Amphotericin-b syrup and itraconazole capsules were given as antifungal prophylaxis. IFI diagnostic procedures consisted of CT, GM, β-D and surveillance culture (SC). At the time of admission a control CT was taken. CT was repeated within 24 hours when pyrexia of ≥38.0°C occurred. If fever showed no improvement, CT was repeated every 3 days (X-ray was also taken). If any change suggesting infection was noted, treatment against IA was considered. GM, β-D and SC were all conducted twice a week from the time of admission until discharge. ≥0.5 GM was regarded as positive and the treatment against IA was started even if there was only one positive result. At present there is no worldwide consensus concerning β-D, thus we considered a value exceeding the cut-off value of the reagent as positive. Treatment was started when there were both a positive result and increasing fever; and treatment against IA or candidiasis depended on imaging findings. Even if β-D was negative, candida detected by SC or diarrhea combined with increasing fever was also an indication for treatment against candidiasis. IA was treated with voriconazole (VRCZ) and candidiasis with micafungin (MCFG). VRCZ and MCFC were administered at 200–300 mg/twice/day and 100–300 mg/day, respectively. When no sufficient effect was observed with VRCZ alone, MCFG was added.Complete remission (CR) and partial remission (PR) were achieved in 81/112 (72%) and 9/112 (8%) episodes, while in 19/112 (17%) no response was obtained and 3/112 (2.7%) episodes resulted in death during chemotherapy. CR rate was comparable among de novo MDS-AML (49/70, 70%), MDS-AML relapse (9/18, 50%) and AML (23/24, 96%). The cause of death associated with chemotherapy was bacteremia 1, bacteremia or IA 1, and cerebral hemorrhage 1. GM was positive in 48 (43%) episodes. The reason for this large number was probably the advanced age of the patients and the long term neutropenia [absolute neutrophil count <500 (median) 27 days]. In spite of higher IA morbidity, mortality rates seemed very low. Furthermore, although GM >2.5 indicates an unfavorable prognosis and >5.0 no hope of survival, none of our patients with GM >2.5 (10 patients) died of IA (2 died of other causes) and all patients with GM >5.0 (4 patients) survived. Candidemia was found in 2 patients (krusei 1, guilliermondii 1) and were treated succesfully. β-D was positive in 46 /112 (41%) episodes and 28/112 (25%) were also positive for GM. As for GM and β-D, GM positivity preceded that of β-D in 9/28 (32%); regarding GM and CT, GM positivity preceded the observation of CT findings in 13/30 (43%).At the beginning of this study, no control CT was obtained. But in the course of the study we found some patients who presented CT findings indicating IA, such as nodular lesions, but with no infection. Thus, we realized the need for a control CT to detect IA more accurately. Each diagnostic procedure has excellent characteristics but it is not sufficient by itself. The results of this single-center clinical study indicate that an improvement of antifungal therapy combined with a battery of diagnostic procedures may allow safe, intensive chemotherapy for many patients with MDS or AML. Disclosures:No relevant conflicts of interest to declare.