Elevated neutrophil-lymphocyte ratio in patients with euthyroid chronic autoimmune thyreotidis

The neutrophil-lymphocyte ratio (NLR), determined from peripheral blood, is accepted as an available and practical indicator of the systemic inflammation. In this study, we aimed to determine whether the NLR was higher in euthyroid chronic autoimmune thyreotidis (CAT) patients compared to a healthy control group.

A total of 112 patients were enrolled in this study, including 59 patients with euthyroid CAT on any form of therapy and 53 healthy controls. Th e CAT patients were similar in age to the healthy control group (mean 33.9±12.8 years versus 30.2±12.4 years, p=0.10). Measurements were available for the white blood cells (WBC), neutrophils, lymphocytes, platelets, C-reactive protein (CRP), thyroid peroxidase immune antibody (anti-TPO), and anti-thyroglobulin immune antibody (anti-TG). The NLR and platelet-lymphocyte ratio (PLR) were calculated. Differences between the CAT and control groups were tested using the student's t-test and the correlations were determined using Pearson's correlation coefficients.

There were no differences between the CAT and control groups for WBCs (7.9±0.3 and 7.4±0.2, respectively; p=0.1) or neutrophils (5.5±0.3 and 5.4±1.1; p=0.9), but lymphocytes were higher in the CAT group (3.1±0.5 vs. 2.04±0.1; p=0.05) as was the NLR (4.0±0.7 vs. 2.0±0.1; p=0.01). Th e NLR was positively correlated with CRP (r=0.6, p<0.001), anti-TPO (r=0.3, p<0.001), anti-TG (r=0.3, p=0.006), WBCs (r=0.4, p<0.001), and the PLR (r=0.73, p<0.001). The PLR was also higher in the CAT than the control group (p=0.02).

In this study, we found that NLR values were higher in euthyroid CAT patients than in a healthy control group and that NLR correlated with autoantibodies used to diagnose the disease.