Diagnostic Utility of the Neutrophil-Lymphocyte Ratio and Absolute Lymphocyte Count in Distinguishing Thyroiditis vs Other Benign Causes of Thyroid Enlargement.

introductionThyroid disorders range from localized lesions, such as colloid goiter, to autoimmune thyroiditis and can present as a tumour mass. Despite a huge number of lesions, they should be classified into two basic categories: one with a diffuse pattern of involvement and the other that results in thyroid gland nodules. Thyroid nodules are frequently found in clinical settings, accounting for 4-7% of the adult population. Thyroiditis, along with hyperplasia, generally affects the entire gland, which is linked to diffuse expansion of the thyroid. Many disorders, including thyroid conditions, can be effectively managed, and their progression can be largely prevented through a well-functioning immune system. Neutrophil-lymphocyte ratio (NLR) and absolute lymphocyte count (ALC) are markers of systemic inflammatory response. There is a paucity of literature available on the correlation of NLR and ALC with thyroiditis compared to other benign thyroid disorders. Current research was conducted to depict the diagnostic utility of NLR and ALC in differentiating between thyroiditis and other benign causes of thyroid enlargement. METHODOLOGY: This is a case-control study conducted from November 2022 to April 2024 (for a period of 18 months). Data were collected from patients with thyroid swelling who underwent fine needle aspiration cytology (ultrasonography-guided or non-USG-guided) from the cytopathology section. Data on the hematological parameters of the same patients were collected from the hematology section after considering the inclusion and exclusion criteria. Data were entered into an MS Excel sheet (Microsoft® Corp., Redmond, WA) and evaluated using SPSS (version 24; IBM SPSS Statistics for Windows, Armonk, NY).

resultsIn the current research, a total of 136 samples were taken. Out of 136 samples, 121 (89.0%) were women, and 15 (11.0%) were men. Hashimoto's thyroiditis (HT) constituted 18.4% (25 cases), and the rest were benign causes of thyroid enlargement, as a control group (81.6%, 111 controls). The mean age for HT was 36.44±12.81 years, while it was 38.45±12.62 years in the control group. The mean total leukocyte count (TLC) for HT was 8651.20±2378.03 cells/cumm, and for the control group, it was 7367.30±2204.37 cells/cumm. The p-value for TLC was 0.011. The mean neutrophil and lymphocyte percentages for HT were 65.44±11.92 and 28±11.31, respectively, while in the control group, it was 68.23±10.44 and 25.91±8.77, respectively. The results obtained for the NLR were 3.17±2.84 in HT and 3.26±2.38 in the control group. The mean of ALC in HT was 2379.32±1137.53 cells/cumm, and in the control group, it was 1843.14±674.35 cells/cumm. The p-value for ALC was 0.002. The results were statistically significant for the total leukocyte count and ALC.

conclusionThe gold standard in the assessment of thyroid disorders is histopathological examination, as the NLR is not specific for thyroid disorders, and this should not be considered as a diagnostic test alone. The NLR, although a cheap and noninvasive marker, has limited value in the diagnosis of thyroid disorders, while the ALC provides additional specificity to this inflammatory profile, which showed significant results in current research. More studies and other inflammatory markers with large sample sizes are needed to establish the correlation between ALC and different thyroid disorders.