Allergic Rhinitis: Diagnosis and Treatment

Rhinitis is a syndrome defined by the symptoms of nasal congestion, postnasal drip, rhinorrhea, sneezing, and nasal itching, usually with physical findings of turbinate edema and increased secretions. The term implies inflammation as an essential component of the pathophysiology, but inflammation may not always be evident or confirmed in the pathophysiology of all rhinitis syndromes. Nevertheless, rhinitis, rather than rhinopathy or another term, is generally used to describe the constellation of symptoms listed. Classification of severity is generally based on symptom intensity and duration rather than physical examination or laboratory findings. Rhinitis may be subdivided into more than nine groups based on probable etiology or associations. These include allergic, idiopathic perennial nonallergic (sometimes referred to as vasomotor rhinitis), infectious, medication related (rhinitis medicamentosa), hormonal, atrophic, polypoid or hyperplastic, and rhinitis associated with systemic diseases. Some authorities divide nonallergic rhinitis into subgroups based on triggers (e.g., weather, odor, alcohol ingestion, or irritants among others), but the symptoms and physical findings of these rhinitis subgroups tend to be more alike than dissimilar, prompting others to classify all into one category, perennial nonallergic rhinitis (PNAR). Occupational rhinitis is a classification sometimes used, referring to irritant, nonallergic rhinitis or allergic rhinitis related to work environments. This chapter focuses on allergic rhinitis and includes the differential diagnosis of other rhinitis syndromes (Table 6.1)