Synergistic action of amphotericin B and rifampin against Rhizopus species

J. C. Christenson, I. Shalit, D. F. Welch, A. Guruswamy, M. I. Marks

Research output: Contribution to journalArticlepeer-review

59 Scopus citations


A 16-year-old diabetic patient developed Rhizopus pneumonia and was initially treated with amphotericin B for 7 days. Because of clinical deterioration of the patient, rifampin was added empirically. The patient improved clinically, and lung tissue removed surgically 8 weeks later showed no fungal elements by histopathological studies or by culture. An in vitro study of amphotericin B alone and in combination with rifampin against the isolate from the patient and 11 additional isolates of Rhizopus spp. was designed. The activity of amphotericin B in the presence of rifampin (10 or 5 μg/ml) increased fourfold against 9 of 10 clinical and 1 of 2 environmental isolates. Amphotericin B activity in the presence of 2 μg of rifampin per ml increased fourfold against 6 of 10 clinical isolates and increased twofold against an additional 3 clinical isolates. Amphotericin B in the presence of 1 μg of rifampin per ml inhibited 9 of 10 isolates at a concentration of one-half the MIC of amphotericin B alone. These findings were confirmed by dose-reponse curves calculated from fungal dry weight determinations of Rhizopus spp. incubated in serial dilutions of amphotericin B combined with rifampin. These observations demonstrate in vitro, and possibly in vivo, synergy between amphotericin B and rifampin against Rhizopus spp.

Original languageEnglish (US)
Pages (from-to)1775-1778
Number of pages4
JournalAntimicrobial Agents and Chemotherapy
Issue number11
StatePublished - 1987

ASJC Scopus subject areas

  • Pharmacology
  • Pharmacology (medical)
  • Infectious Diseases

Fingerprint Dive into the research topics of 'Synergistic action of amphotericin B and rifampin against Rhizopus species'. Together they form a unique fingerprint.

Cite this