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

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.

Keywords: antimicrobial resistance; bacterial keratitis; epidemiology; etiology; fungal keratitis; microbial keratitis.

Fig. 1 -

World incidence and etiological predominance of MK at a glance, grouped into region showing wide disparity in incidence between European and Northern American studies and those from South and South-East Asia, as well as relative paucity in available worldwide epidemiological data. Circles have been placed showing the location of incidence studies. Location of studies that reported bacterial keratitis (squares) and fungal keratitis (triangles) predominance has also been marked. *Per 100,000 person-years. ** NS, not stated.