Objective To analyze the correlation of inflammatory indicators of neutrophil-to-lymphocyte ratio(NLR),platelet-to-lymphocyte ratio(PLR),monocyte-to-lymphocyte ratio(MLR),and systemic immune-inflammation index(SII)with traditional Chinese medicine(TCM)syndrome types and Chinese version of Thyroid Imaging Reporting and Data System(C-TIRADS)classification and properties of nodules in the patients with thyroid nodules(TN),thus to provide evidence for guiding TCM syndrome differentiation and treatment,and for assessing C-TIRADS classification and properties of the nodules in patients with TN.Methods A retrospective analysis was carried out in 140 inpatients who were diagnosed as TN and had underwent thyroidectomy during the period of January 2021 to January 2024 in the Department of General Surgery of Guangzhou Integrated Chinese and Western Medicine Hospital Affiliated to Guangzhou University of Chinese Medicine(Guangzhou Hospital of Integrated Traditional and West Medicine).The patients were allocated to various group with reference to TCM syndrome types,C-TIRADS classification,and the properties of TN.The correlation of each clinical indicator with TCM syndrome types and C-TIRADS classification and properties of TN was analyzed.The Spearman correlation coefficient was employed for evaluating the correlation of clinical indicators with the C-TIRADS classification and properties of TN,receiver operating characteristic curve(ROC)was used to analyze the predictive value of NLR,MLR,PLR,and SII for the properties of nodules in patients with TN,and the Youden's Index was used to determine the cutoff value for optimal prediction.Results(1)According to the criteria of TCM syndrome differentiation,72 cases were differentiated as qi stagnation and phlegm obstruction syndrome,65 cases as phlegm accumulation and blood stasis syndrome,and 3 cases as heart-liver yin deficiency syndrome.For the number of cases of heart-liver yin deficiency syndrome was too small,only the first two syndromes were included for the analysis.(2)The levels of free T3(FT3)and free T4(FT4)in the patients of qi stagnation and phlegm obstruction syndrome were higher,and the levels of anti-thyroid peroxidase antibody(A-TPO),anti-thyroglobulin antibody(A-TG),neutrophil(NEU),NLR,and SII were lower than those in the patients of phlegm accumulation and blood stasis syndrome,the differences being all statistically significant(P<0.05 or P<0.01).(3)The levels of NLR,PLR,and SII in the patients with C-TIRADS3 classification were lower than those in the patients with C-TIRADS4 classification,the differences being all statistically significant(P<0.05 or P<0.01);no statistically significant difference of MLR was presented between the patients with C-TIRADS3 classification and those with C-TIRADS4 classification(P>0.05).(4)The levels of NLR,PLR,MLR,and SII in patients with benign nodules were lower than those in patients with malignant nodules,the differences being statistically significant(P<0.05 or P<0.01).(5)The Spearman correlation analysis showed that NLR,PLR,and SII were positively correlated with the C-TIRADS classification of the nodules,and NLR,PLR,MLR,and SII were positively correlated with the properties of the nodules,the differences being all statistically significant(P<0.05 or P<0.01).(6)The levels of NLR,MLR,PLR,and SII in patients with high-risk TN exerted a certain predictive value for the properties of the nodules,and their area under the curve(AUC)was 0.645,0.641,0.604,and 0.716,respectively,the differences being statistically significant(P<0.05 or P<0.01).For the prediction of nodule properties by NLR,MLR,PLR,and SII levels in patients with high-risk TN,their cutoff values and the corresponding sensitivities and specificities were 2.261(0.551,0.791),138.108(0.735,0.527),5.132(0.714,0.495),493.114(0.776,0.615),respectively;and their Youden's Index was 0.342,0.262,0.209,0.391,respectively.Conclusion The results indicated that in patients with TN,the FT3 and FT4 levels are positively correlated with the qi stagnation and phlegm obstruction syndrome;the values of A-TPO,A-TG,NEU,NLR,and SII are positively correlated with the phlegm accumulation and blood stasis syndrome;NLR,PLR and SII values are positively correlated with C-TIRADS classification;NLR,PLR,PLR,SII values are positively correlated with malignant TN.NLR,MLR,PLR,SII values exert high efficiency for the prediction of the properties of nodules in patients with TN.