Evidence check: tTG IgA in the context of stress

The provided context does not contain specific information about tTG IgA in relation to stress. tTG IgA is a well-established biomarker for celiac disease, not for stress. There is some evidence that psychological stress can increase intestinal permeability and potentially exacerbate immune responses in individuals with celiac disease, but the direct link between stress and elevated tTG IgA is weak and not clinically actionable. Elevated tTG IgA should primarily be evaluated for celiac disease. Stress alone is not known to cause false-positive tTG IgA results. The evidence for a direct connection is limited to mechanistic hypotheses and a few observational studies. Without relevant sources from the given context, the evidence rating is unclear.