A Controversial New Approach to Address Hematological Parameters in Hashimoto's Thyroiditis

Hashimoto's thyroiditis (HT) is a common autoimmune disorder. Genetic, environmental, and immunological factors all play a role in the pathogenesis of HT, but the effects of lymphocytes and platelets on the pathophysiology of HT are still unknown. In this study, we evaluated the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and mean platelet volume (MPV) in HT groups and HT subgroups with low cardiovascular risks.

This study included 92 patients with HT and 38 control subjects. Among the HT patients, three subgroups were formed according to thyroid function: overt (n = 12), subclinical (n = 38), and euthyroid (normally functioning thyroid; n = 42).

Age and gender distributions were similar between the patient and control groups. Body mass index was higher in the patient group than in the control group. The C reactive protein level was higher in patients than controls (p = 0.064). The thyroid stimulating hormone (TSH) level was higher and the mean free thyroxine level lower in the patient group than in the control group (p < 0.05). There were no differences between the groups with regard to leukocytes, neutrophils, platelets, or MPV (p > 0.05). The NLR and PLR were significantly different in one subgroup of HT patients relative to healthy subjects (p < 0.05). However, we did not find any statistical differences in the MPV among the three subgroups (p = 0.547). A positive correlation was found among the NLR, anti-thyroglobulin (TG) antibodies, and anti-thyroid peroxidase (TPO) antibodies (p < 0.01), although there was a negative correlation between the PLR, TSH, anti-TPO, and anti-TG (p < 0.001).

A single marker or panel of biomarkers is not a consistent indicator of HT, but NLR combined with PLR testing may offer a more reliable diagnosis.