Is tTG IgA useful for Haut?

tTG IgA is the primary serological marker for celiac disease, which can present with skin manifestations such as dermatitis herpetiformis – an intensely itchy, blistering rash. Therefore, tTG IgA testing is indirectly useful for skin when celiac disease is suspected as the underlying cause. However, it is not indicated for general skin conditions like acne, eczema, or psoriasis without celiac suspicion. The evidence for celiac diagnosis is human-strong (guidelines, meta-analyses). Caveat: The test requires a gluten-containing diet and must be interpreted by a physician. False negatives can occur in IgA deficiency. For skin health without celiac risk factors, this test has no proven utility.