The persistent dilemma of microbial keratitis: Global burden, diagnosis, and antimicrobial resistance

  • Lawson Ung
    Affiliations
    Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
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  • Paulo J.M. Bispo
    Affiliations
    Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA

    Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
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  • Swapna S. Shanbhag
    Affiliations
    Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA

    Tej Kohli Cornea Institute, L. V. Prasad Eye Institute, Hyderabad, India
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  • Michael S. Gilmore
    Affiliations
    Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA

    Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
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  • James Chodosh
    Correspondence
    Corresponding author: Dr. James Chodosh, MD, MPH, Massachusetts Eye and Ear, 243 Charles Street, Boston, Massachusetts 02114, USA.
    Affiliations
    Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA

    Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
    Search for articles by this author

      Abstract

      Microbial keratitis is a potentially blinding condition that must be treated emergently to preserve vision. Although long recognized as a significant cause of corneal blindness, our understanding of its true global scale, associated burden of disease, and etiological patterns remains somewhat limited. Current epidemiological data suggest that microbial keratitis may be epidemic in parts of the world—particularly within South, South-East, and East Asia—and may exceed 2 million cases per year worldwide. Etiological patterns vary between economically developed and developing countries, with bacterial predominance in the former and fungal predominance in the latter. The key to effective management lies in timely diagnosis; however, the current gold standard of stain and culture remains time consuming and often yields no clinically useful results. For this reason, there are attempts to develop highly sensitive and accurate molecular diagnostic tools to provide rapid diagnosis, inform treatment decision making, and minimize the threat of antimicrobial resistance. We provide an overview of these key areas and of avenues for further research toward the goal of more effectively addressing the problem of microbial keratitis on both an individual and public health level.

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      Linked Article

      • Povidone-iodine can be used in the treatment of microbial keratitis
        Survey of OphthalmologyVol. 64Issue 6
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          We have read the article by Ung and coworkers on the problems related with diagnosis and treatment of microbial keratitis, in which authors elegantly presented difficulties with antibiotic use and the increasing importance of antibiotic resistance.5 We would like to supplement their interesting review with a few comments on the use of povidone-iodine (PVI), which is an interesting option in the treatment of ocular surface infections.
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