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Outcomes of Pythium keratitis: A Meta-Analysis of Individual Patient Data

  • Ocular Surface (A Galor, Section Editor)
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Abstract

Purpose of Review

To review and perform a meta-analysis of individual patient data from observational studies describing medical treatment of Pythium keratitis. The outcomes of interest were therapeutic penetrating keratoplasty (TPK) and globe removal (evisceration, enucleation, or exenteration); the main exposures were linezolid and azithromycin use.

Recent Findings

Of 46 eligible articles, individual patient data were available for 306 eyes (34 studies). Pythium keratitis was associated with high rates of TPK (80%, 95% CI 70–87%) and globe removal (25%, 95% CI 13–43). In multivariable models adjusting for age and country, fewer TPKs were performed in patients treated with azithromycin (RR = 0.80, 95% CI 0.67–0.96; P = 0.04) and linezolid (RR = 0.82, 95% CI 0.67–0.99; P = 0.02).

Summary

Studies of Pythium keratitis reported high rates of TPK and globe removal. The use of azithromycin and linezolid was associated with a lower rate of TPK. While promising, these results should be interpreted with caution given the biases inherent to observational studies.

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Funding

This project was supported by the Fogarty International Center of the National Institutes of Health (NIH) under Award Number D43TW009343 and the University of California Global Health Institute (UCGHI). The work was also supported by the All May See Foundation and Research to Prevent Blindness.

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Author notes

  1. Binh Cao and Vishnu Teja Gonugunta contributed equally.

Authors and Affiliations

  1. Francis I Proctor Foundation, University of California, 490 Illinois Street, Second Floor, Box 0944, San Francisco, CA, 94158, USA

    Binh Cao & Jeremy D. Keenan

  2. Department of Cornea and Refractive Surgery, Aravind Eye Hospital Madurai, Madurai, India

    Vishnu Teja Gonugunta, Naveen Radhakrishnan & N. Venkatesh Prajna

  3. Department of Ocular Microbiology, Aravind Eye Hospital Madurai, Madurai, India

    Prajna Lalitha

  4. Dr. Om Parkash Eye Institute, Amritsar, India

    Bharat Gurnani & Kirandeep Kaur

  5. Aravind Eye Hospital and Post Graduate Institute, Pondicherry, India

    Bharat Gurnani & Kirandeep Kaur

  6. C J Shah Cornea Services, Dr G Sitalakshmi Memorial Clinic for Ocular Surface Disorders, Sankara Nethralaya, Chennai, India

    Geetha Iyer, Shweta Agarwal & Bhaskar Srinivasan

  7. Department of Ophthalmology, University of California, San Francisco, USA

    Jeremy D. Keenan

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Cao, B., Gonugunta, V.T., Radhakrishnan, N. et al. Outcomes of Pythium keratitis: A Meta-Analysis of Individual Patient Data. Curr Ophthalmol Rep 10, 198–208 (2022). https://doi.org/10.1007/s40135-022-00302-7

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