S2k-Guideline - Standardized application of the nasal and conjunctival provocation test on allergic diseases of the upper airways : of the German Society for Allergology and Clinical Immunology (DGAKI), German Society of Oto-Rhino-Laryngology, Head and Neck Surgery (DGHNO-KHC), German Dermatological Society (DDG), German Society of Pediatrics and Adolescent Medicine (DGKJ), German Society of Ophthalmology (DOG), German Respiratory Society (DGP), German Society for Occupational and Environmental Medicine (DGAUM), German Society for Pediatric Allergology and Environmental Medicine (GPA), German Society for Pediatric Pulmonology (GPP), Ärzteverband Deutscher Allergologen (AeDA), and German Professional Association of Otorhinolaryngologists (BVHNO).

Broad evidence confirms that AR (ICD J30.3) is a chronic disease with high prevalence among children and adults worldwide. Its consequences, both from a public health perspective and at the level of the individual patient, are often underestimated, and the condition is inadequately treated. In addition, AR is often related to comorbidities with additional impact on diseases-severity. Allergen provocation of the easily accessible nasal (nasal allergen provocation test: NPT) or conjunctival mucosa (conjunctival allergen provocation test: CPT) reproduces the allergen-dependent, IgE-mediated allergic reaction under controlled and standardized conditions. These measures are regarded as the diagnostic gold standard, particularly in cases of unclear results in primary allergological tests, enabling clinically relevant identification of the causative allergen. Approved test allergens are critical for ensuring the methodological quality of the NPT. However, their availability is increasingly limited, although adequate quantities of allergen solutions remain indispensable for high-quality nasal allergen testing. Unilateral allergen provocation has been established in the clinical routine for decades in Germany. However, scientific evidence for unilateral application of the test allergen is pending. International position papers differ from this recommendation. The CPT is a simple, safe, and well-tolerated measure. It is primarily used in perennial and, in selected cases, seasonal allergic conjunctivitis. This method is less commonly applied for vernal keratoconjunctivitis and atopic keratoconjunctivitis. It is primarily used to confirm the underlying allergen, particularly when establishing the indication for allergen immunotherapy (AIT). It can also be employed to monitor treatment effects such as e.g., AIT or pharmacotherapy. Although highly sensitive, the procedure of nasal ASA provocation remains a time-consuming procedure. While challenging in children, NPT provides clinically relevant additional diagnostic information on the causes of the allergic symptoms. Allergological diagnostic work-up also includes pulmonary assessment, particularly in patients with established asthma or symptoms suggestive of asthma. Both AAR and PNIF are applied as standard procedures for assessing the outcome of NPT in Germany. In individual cases, other rhinometric methods may also be used.