Hashimoto’s thyroiditis (HT) is an autoimmune thyroid disease with characteristic lymphocytic infiltration and fibrosis. Chronic autoimmune changes that occur in the thyroid gland in HT may also affect the lacrimal gland. Objectives: This study aimed to analyze tear biomarkers and explore correlations between these biomarkers and clinical ocular parameters in patients with HT. Methods: A total of 150 participants were divided into three groups: HT (N = 50), non-HT DED (N = 50), and healthy controls (N = 50). The participants underwent a series of diagnostic tests for DED, including the Ocular Surface Disease Index, Tear Break-Up Time, Lid-Parallel Conjunctival Folds, Schirmer test without anesthetic, lissamine green and fluorescein staining. Tear samples were analyzed for cytokine and enzyme levels (interleukin 1β, tumor necrosis factor α, interleukin 6 (IL-6), interleukin 8, interleukin 10 (IL-10), interleukin 17A, matrix metalloproteinase 9 (MMP-9)) using ELISA and multiplex immunoassay. Statistical analyses were conducted to compare groups and assess biomarker correlations. Results: Dry eye disease was observed in more than half of the study group (27/50), with severe symptoms observed in 48.15% of the DED HT subgroup. IL-6 levels were significantly elevated in the DED HT subgroup compared to the non-HT DED group (p = 0.010), suggesting specificity for HT-associated DED. MMP-9 was elevated in both the HT and non-HT DED groups (p < 0.001) but lacked specificity for HT (p = 0.059). The DED HT subgroup exhibited significantly lower IL-10 levels (p = 0.008). Lissamine green staining and LIPCOF were significantly higher in the DED HT subgroup (p < 0.001). Conclusions: Dry eye disease is common in euthyroid HT patients without signs of TAO. This study highlights the potential role of IL-6. Lissamine green staining and LIPCOF are valuable diagnostic tools for assessing the ocular surface in DED HT patients.

Background/Objectives: Human β-defensin 2 (HBD2) is a protein that plays an important role in activating the immune system by modulating spinal pathways and the inflammatory response. According to previous research, HBD2 was proven to be important in chronic spontaneous urticaria (CSU) (their values were significantly elevated in CSU patients, with a significant correlation between HBD2 levels and the percentage of peripheral basophils, suggesting that elevated HBD2 levels may be a potential marker of basophil and mast cell activation), which led us to additional research on the HBD2 molecule in isolated chronic angioedema. The aim of this research is to examine HBD2 values in the saliva and serum of patients with isolated angioedema, as a potential biomarker of the disease. Methods: This cross-sectional study involved a total of 102 participants, involving three groups: 33 patients with isolated chronic non-hereditary angioedema (AE) (defined as sudden onset of localized edema without chronic urticaria), 33 patients with angioedema associated with chronic urticaria (CU+AE), and 35 healthy participants (controls, CTRL). They provided a saliva sample to determine HBD2 levels using an ELISA (Enzyme-Linked Immunosorbent Assay). Subsequently, a peripheral blood sample (serum) was taken from the participants to determine HBD2 levels using the same ELISA. Results: Salivary HBD2 levels were significantly higher in those with CU+AE than in the CTRL (p = 0.019). While salivary HBD2 values differed between those with angioedema and CTRL, the serum HBD2 values did not. Also, no correlation between the levels of HBD2 in saliva and serum was found. Conclusions: Since we found that salivary HBD2 values were significantly higher in those with CU+AE than in CTRL, this points to a possible role of the HBD2 molecule in pathogenesis of AE (namely, that it induces degranulation in mast cells and vascular permeability, and has antimicrobial properties) Therefore, more research is needed to determine how reliable salivary HBD2 measurement is, as well as its significance.

Background: Human β-defensin 2 (HBD2) is a protein important in immune system activation, produced by epithelial cells, mainly as a result of contact with microorganisms or the action of various pro-inflammatory cytokines. According to previous research, it has proven to be important in chronic urticaria, leading us to research on the HBD2 in isolated chronic angioedema. Methods: This cross-sectional study involved 102 participants (three groups): 33 patients with isolated chronic non-hereditary angioedema (AE); 33 patients with angioedema associated with chronic urticaria (CU+AE); and 35 healthy controls (CTRL). They provided saliva and serum samples to determine HBD2 levels using the Enzyme-Linked Immunosorbent Assay-ELISA. Results: Salivary HBD2 levels were significantly higher in those with CU+AE than in the CTRL (p=0.019). While salivary HBD2 values differed between those with angioedema and CTRL, the serum HBD2 values did not. Also, no correlation between the levels of HBD2 in saliva and serum was found. Conclusions: Since we found that salivary HBD2 values were significantly higher in those with CU+AE than in CTRL, this points to a possible role of the HBD2 molecule in pathogenesis of AE. Therefore, more research is needed to determine how reliabile salivary HBD2 measurement is and its significance.