Amphotericin B toxicity reduced by administration in fat emulsion.

OBJECTIVE

To report a patient with intolerance to amphotericin B reversed by preparing the antifungal in fat emulsion 20% and to review the medical literature on innovative formulations of amphotericin B.

CASE SUMMARY

A 51-year-old man diagnosed with acute myelogenous leukemia was treated with standard induction chemotherapy. Empiric antibiotic therapy was initiated 2 days postchemotherapy; however, the patient continued to be febrile until day 7. At this time amphotericin B 35 mg/250 mL D5W over 4 hours was administered. Despite premedication, the patient experienced severe rigors, chills, and fever. As the result of continuing infusion-related adverse events, the patient refused further therapy after the third daily dose. In an attempt to reduce the infusion-related events, a trial of amphotericin B 35 mg/35 mL of fat emulsion 20% was administered over 2 hours after patient consent was obtained. Premedication was administered and the patient tolerated therapy without adverse events. Amphotericin B dosage escalations to 50 and 70 mg were tolerated similarly. During this treatment the patient became afebrile and the serum creatinine concentration decreased to normal.

DISCUSSION

Despite significant toxicities and the development of newer antifungal agents, amphotericin B remains the drug of choice for the empiric coverage of suspected fungal infection in neutropenic patients. Amphotericin B often exacerbates the nephrotoxicity of other agents characteristically prescribed in these patients. Furthermore, infusion-related events, if not intolerable, can dramatically reduce the patient's quality of life. For these reasons, novel means of amphotericin B administration are being explored.

CONCLUSIONS

The delivery of amphotericin B in a lipid diluent may have substantial benefit in reducing the nephrotoxicity and infusion-related events associated with the antifungal. Prospective clinical trial comparing lipid-complexed amphotericin B with liposomal and approved formulations of amphotericin B are essential to define potential differences in toxicity and efficacy.