Can tTG IgA help with Müdigkeit?

tTG IgA (tissue transglutaminase antibodies) is a well-established biomarker for celiac disease, an autoimmune condition triggered by gluten. Fatigue is a common but non-specific symptom of celiac disease, often due to malabsorption, iron-deficiency anemia, or chronic inflammation. A positive tTG IgA test can therefore point to underlying celiac disease, and treatment (gluten-free diet) may significantly improve fatigue in affected individuals. However, tTG IgA is not a general fatigue test. The evidence linking tTG IgA to fatigue is indirect: strong human evidence for celiac diagnosis, but moderate for fatigue as a presenting symptom. In unexplained fatigue without other celiac features, the pre-test probability is low. A negative test does not rule out other causes of fatigue. Testing should only be performed when celiac disease is clinically suspected, not as a screening for general tiredness. Caveat: tTG IgA can be falsely negative in IgA deficiency; IgG-based testing is then required.