# New Biomarkers for Patients With Fungal Keratitis From Blood Routine Examination: Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio

## TL;DR

This study shows that blood tests measuring NLR and PLR can help detect and monitor fungal eye infections, especially in areas with limited medical resources.

## Contribution

The study introduces NLR and PLR as novel, accessible biomarkers for diagnosing and predicting outcomes in fungal keratitis.

## Key findings

- NLR and PLR were significantly higher in fungal keratitis patients compared to controls.
- NLR strongly correlated with inflammation severity, more so than PLR.
- Higher NLR and PLR values were linked to worse treatment outcomes in FK patients.

## Abstract

Purpose: To assess the potential of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) as novel diagnostic and prognostic biomarkers in fungal keratitis (FK).

Methods: This study was carried out retrospectively in 77 FK patients and 77 matched cataract controls from Henan Eye Hospital. Peripheral venous blood samples were collected via venipuncture and analyzed using complete blood count for routine clinical evaluation. FK patients were classified into three subgroups: Fusarium, Aspergillus, and Candida groups. Inflammation severity was quantified using standardized clinical scoring. The treatment modalities were used to divide the FK patients into enucleation and nonenucleation groups.

Results: NLR and PLR were significantly elevated in FK versus controls (p < 0.001). NLR correlated strongly with inflammation scores (r = 0.535, p < 0.0001), exceeding PLR's moderate correlation (r = 0.311, p=0.0059). FK patients in the enucleation group had significantly higher NLR (p=0.012) and PLR (p=0.021) values than those in the nonenucleation group. There were no significant biomarker differences across fungal species (p > 0.05).

Conclusion: Elevated NLR and PLR values during routine laboratory testing might serve as supplementary indicators for early suspicion of FK and monitoring inflammatory progression, particularly in resource-limited settings where specialized ophthalmic diagnostics are unavailable.