Decreased neutrophil-to-lymphocyte ratio and increased lymphocyte-to-monocyte ratio values might suggest impaired blood aqueous barrier function in Fuchs uveitis syndrome, according to a study published in the Canadian Journal of Ophthalmology.
The cross-sectional, comparative study evaluated the inflammatory indices of complete blood count and ocular examination findings in 140 people, 70 diagnosed with Fuchs uveitis syndrome and a control group of 70 healthy individuals who did not have it. Investigators used the Pearson correlation test to analyze the correlation in the severity of anterior chamber reaction, duration of Fuchs uveitis syndrome, and complete blood count indices.
They found that in the Fuchs uveitis syndrome patients, the mean lymphocyte count and lymphocyte-to-monocyte ratio (LMR) were significantly higher than in the control group (P =.001 and P <.001, respectively). In addition, in the Fuchs uveitis syndrome group, the mean monocyte count and neutrophil-to-lymphocyte ratio were significantly lower than in the control group (P =.010 and P =.003, respectively). For receiver operating characteristic curve analysis, area under the curve for lymphocyte-to-monocyte ratio was 0.834, with sensitivity of 82.6% and specificity of 80.0% and for neutrophil-to-lymphocyte ratio, the same measurement was 0.789, with sensitivity of 71.2% and specificity of 70.0%.
They also found a positive correlation with duration of Fuchs uveitis syndrome and lymphocyte-to-monocyte ratio (P =.001, r=0.574).
The study did have limitations, which included that, because of its retrospective nature, investigators couldn’t look at aqueous humor samples. “Had we been able to study the aqueous humor immunology, we could have made correlation measurements between inflammation indices of [complete blood count] and the aqueous humor,” the study says. Additionally, the amount of patients involved was limited, and a cohort study would offer information this study couldn’t. Finally, they only used polymerase chain reaction (PCR) testing to exclude etiologies with similar aspects in suspicious cases.
“Our results support the assertion that [Fuchs uveitis syndrome] exhibits changes in the inflammatory markers of peripheral blood. Especially, an increase in the [lymphocyte-to-monocyte ratio] and a decrease in the [neutrophil-to-lymphocyte ratio] may be caused by the chronic and low-grade course of the disease,” investigators report.
Simsek S, Ozdal PC. Inflammatory markers of complete blood count in Fuchs uveitis syndrome. Can J Ophthalmol. Published online November 21, 2020. doi:10.1016/j.jcjo.2020.10.016