Allergic rhinitis - making the correct diagnosis

The symptoms of rhinosinusitis occur in a variety of sinonasal conditions, which may be broadly classified as allergic (seasonal, perennial or occupat ional rhinitis/rhinosinusitis) or non-allergic (caused by infection, or non -infectious, e.g. drug-induced or idiopathic). Correct diagnosis is importa nt for optimal management. A thorough history should be taken, followed by general and endoscopic examinations and confirmatory investigations. Carefu l examination should reveal obvious alternative causes of symptoms, such as polyps or tumours. If allergy is suspected, this can be confirmed by furth er tests, particularly the skin-prick test or measurements of serum specifi c IgE. Imaging techniques, usually X-rays or CT scanning, are of use if a s ystemic condition or major sinonasal disorder needs to be excluded. Other u seful diagnostic aids are measurements of nasal peak flow, rhinomanometry, acoustic rhinometry, olfactory threshold, and measures of mucociliary funct ion (which may include biopsy for electron microscopy).