To the Editor: We read with interest the report about fungal infection from Fusarium in children with refractory hematologic malignancies by Mangini and de Camargo (1). However, we wish to comment on the type, dosage and duration of the treatment with amphotericin-B (Ampho-B) used by Mangini and de Camargo. We believe that, if there are any suspicious lesions observed in chest or abdominal CT scans or if there is persistent fever in patients with hematologic malignancies, doses of Ampho-B should be gradually increased (4-8 mg/kg/ day). Owing to dose-limiting renal side effects of conventional Ampho-B (>1 mg/kg/day), liposomal (L-Ampho-B) or lipid complex forms (LC-Ampho-B) of the drug should be substituted when such high doses are requried (2-4).
We had a similar case of invasive Fusarium spp. infection in a child with AML following high doses of cytarabine (total 24 g in 9 days). It has been used as intensification therapy (according to the CCG 2961 AML protocol). The patient developed severe neutropenia (<100 neutrophils/ml) and fever of unknown origin 2 days after the termination of chemotherapy.
Antibacterial (ceftazidime, amikasin, and vancomycin) and antifungal (L-Ampho-B, 1 mg/kg/day) therapies were started concomitant with febrile neutropenia. Chest and abdominal CT scans were taken on day 14 that revealed pulmonary and hepatic hypodense areas indicating fungal involvement of these organs. Thus, the dose of L-Ampho-B was gradually increased, i.e., 1 mg/kg/day every 2 days, until a maximum dose of 4 mg/kg was attained. Eventually the patient became afebrile. On day 16, the microbiology department reported that all blood cultures from peripheral veins and central venous catheters were positive for Fusarium spp. Therefore, the central nervous catheter was removed. Her response and tolerance to high doses of L-Ampho-B were found to be satisfactory. Hypokalemia was the only side effect of the high-dose L-Ampho-B, which was handled easily by intravenous administration of potassium. On completion of 14 days of 4 mg/kg/day L-Ampho-B, the dose was ta-pered to 1 mg/kg/day, which was maintained for another 2 months. Five months later, on her last visit, she was doing well without any complication or relapse of the infection.
Additional clinical experience is required to establish the most effective dosage, and duration of treatment with L-Ampho-B in patients with invasive fungal infections from Fusarium spp.