Acanthamoeba Keratitis: an update on amebicidal and cysticidal drug screening methodologies and potential treatment with azole drugs

Expert Rev Anti Infect Ther. 2021 Nov;19(11):1427-1441. doi: 10.1080/14787210.2021.1924673. Epub 2021 May 19.


Introduction: Acanthamoeba encompasses several species of free-living ameba encountered commonly throughout the environment. Unfortunately, these species of ameba can cause opportunistic infections that result in Acanthamoeba keratitis, granulomatous amebic encephalitis, and occasionally systemic infection.Areas covered: This review discusses relevant literature found through PubMed and Google scholar published as of January 2021. The review summarizes current common Acanthamoeba keratitis treatments, drug discovery methodologies available for screening potential anti-Acanthamoeba compounds, and the anti-Acanthamoeba activity of various azole antifungal agents.Expert opinion: While several biguanide and diamidine antimicrobial agents are available to clinicians to effectively treat Acanthamoeba keratitis, no singular treatment can effectively treat every Acanthamoeba keratitis case.Efforts to identify new anti-Acanthamoeba agents include trophozoite cell viability assays, which are amenable to high-throughput screening. Cysticidal assays remain largely manual and would benefit from further automation development. Additionally, the existing literature on the effectiveness of various azole antifungal agents for treating Acanthamoeba keratitis is incomplete or contradictory, suggesting the need for a systematic review of all azoles against different pathogenic Acanthamoeba strains.

Keywords: Acanthamoeba; amebicidal; antifungal; assay; azole; cell viability; cysticidal; drug screening; drugs; keratitis treatments.

Publication types

  • Research Support, N.I.H., Extramural
  • Systematic Review

MeSH terms

  • Acanthamoeba Keratitis* / drug therapy
  • Acanthamoeba*
  • Amebicides* / pharmacology
  • Amebicides* / therapeutic use
  • Azoles / pharmacology
  • Azoles / therapeutic use
  • Drug Evaluation, Preclinical
  • Humans


  • Amebicides
  • Azoles