Fig 2: Association of CSU with TPO, anti-TPO IgG, and anti-TPO IgE.Figure A and B: Frequency of anti-TPO IgG and anti-TPO IgE. Figure C: autoantibodies interaction. Figure D: Blood levels of TPO. Figure E: correlation between TPO, anti-TPO IgE, and anti-TPO IgG. Figure F: Association of TPO and autoantibodies with CSU. CSU: Chronic spontaneous urticaria. Non-CSU: Non chronic spontaneous urticaria. TPO: thyroperoxidase

Fig 3: Serum anti-TPO antibody levels in HCV patients and controls, presented as mean ± SD. Between-group comparisons were performed using independent t-tests, dashed horizontal lines indicate median values, *** indicates p < 0.001.

Fig 4: Scatter plots with linear regression lines showing Pearson correlations between anti-TPO antibody titers and (A) TSH (r = +0.62), (B) fT3 (r = −0.48), and (C) fT4 (r = −0.53) in HCV patients (n = 100). Shaded areas represent 95% confidence intervals. Shading = 95% confidence interval. The corresponding Pearson’s r values are reported in Table 2.