Objective: Serum C-X-C motif chemokine 10 (CXCL10) levels have been shown to be elevated in autoimmune thyroid diseases (AITD). This study sought to determine whether newly diagnosed AITD patients with neuromuscular findings had higher levels of CXCL10 than those without neuromuscular manifestations.Design: A total of 80 patients were recruited to the study, which included treatment-naive hypothyroid Hashimoto's thyroiditis (n = 19) and hyperthyroid Graves' disease (GD; n = 21), euthyroid thyroid autoantibody-positive (n = 20) and-negative (n = 20) patients.Methods: All patients underwent a thorough sensorimotor and neuromuscular examination. Serum samples were kept in-20°C for further CXCL10 measurements with ELISA.Results: There was a significant difference with regard to serum CXCL10 levels only between GD and euthyroid thyroid autoantibody-negative patient groups [187(12-418) vs. 37.5(2-542) pg/ml, p < 0.05]. However, a comparison of newly diagnosed AITD patients with and without neuromuscular manifestations in terms of serum CXCL10 levels yielded no significant difference. When a correlation of existence of a neuromuscular manifestation and serum CXCL10 levels was evaluated, a significantly positive correlation was noted between carpal tunnel syndrome (CTS) and serum CXCL10 levels [207 (95-748) pg/ml in CTS-positive vs. 117 (2-977) pg/ml in CTS-negative patients, p < 0.05].Conclusions: In this study, from a number of neuromuscular manifestations, only the existence of CTS correlated with significantly higher CXCL10 levels in the whole study group. Further studies with larger numbers of patients with autoimmune-based hyper-and hypothyroidism may better clarify the hypothesis regarding a relationship between serum CXCL10 levels and neuromuscular manifestations of AITD. © 2011 Informa UK, Ltd.