Evidence check: Stuhlprobe in the context of allergy

Stool tests are increasingly marketed for allergy and food sensitivity testing, often under the guise of microbiome analysis. However, the scientific evidence supporting stool-based allergy diagnosis is weak. While the gut microbiome is known to influence immune development and allergic sensitization, no validated stool biomarker currently exists for diagnosing allergies in clinical practice. Guidelines (e.g., EAACI, AAAAI) recommend skin prick tests or specific IgE blood tests as the gold standard. Stool tests may provide exploratory insights but have high false-positive rates and lack standardization. Acting on such results—especially removing foods from a child’s diet—can lead to nutritional deficiencies without proven benefit. For a reliable allergy assessment, consult an allergist. The evidence for stool testing in allergy is best described as 'marketing' or 'unclear'.