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The following is a summary of “Exploring leukocyte differential count ratio profiles as inflammatory biomarkers in diabetic retinopathy: a systematic review and meta-analysis,” published in the May 2025 issue of BMC Ophthalmology by Harley et al. 

Diabetic retinopathy (DR) has become more prevalent, causing blindness, especially in developing countries, with delayed diagnoses due to limited access to ophthalmologists, underscoring the need for accessible screening methods.  

Researchers conducted a retrospective study to examine the association between leukocyte differential count ratios— Neutrophil-to-Lymphocyte Ratio (NLR), Platelet-to-Lymphocyte Ratio (PLR), Monocyte-to-Lymphocyte Ratio (MLR), and Systemic Immune-Inflammation Index (SII)—and the stages of diabetic retinopathy.  

They performed a comprehensive literature search across multiple databases up to September 2024 to identify studies that explored the relationship between leukocyte differential count ratio profiles and DR. Meta-analyses were conducted using a Review Manager. The Newcastle Ottawa Scale (NOS) was employed to assess the quality of the studies that were included.  

The results showed that 38 studies were included in the systematic review, with 27 studies in the meta-analysis. Significant differences in NLR and PLR values were observed among the groups, with higher values in the Proliferative Diabetic Retinopathy (PDR) group (0.68 [95% CI 0.42–0.95], P< 0.05 and 19.57 [95% CI 10.68–28.46], P< 0.05, respectively). Additionally, a significant difference was found in the SII value, 202.53 [95% CI 196.19–208.86], P< 0.05 and no significant difference was observed in the MLR values among the groups (P> 0.05).  

Investigators concluded that NLR, PLR, and SII were associated with both the presence and progression of DR, with higher levels of NLR and PLR indicating a greater risk and severity of the disease, though further validation with other clinical parameters was needed to confirm the diagnosis. 

Source: bmcophthalmol.biomedcentral.com/articles/10.1186/s12886-025-04075-y