ABSTRACT
The recent ARIA (Allergic Rhinitis and its Impact on Asthma) document has classified rhinitis and its differential diagnosis as shown in Boxes 2.1 and 2.2 (Bousquet et al. 2001). In practice, the simple division shown in Figure 2.1 is useful to bear in mind when investigating a patient. However, these divisions are not mutually
Infectious viral bacterial other infective agents
Allergic intermittent persistent
Occupational (allergic or non-allergic) intermittent persistent
Drug-induced aspirin other medications
Hormonal
Other causes non-allergic rhinitis with eosinophilia syndrome irritants food emotional atrophic gastro-oesophageal reflux
Idiopathic
(Source: Bousquet et al. 2001.)
exclusive, for example allergic rhinitis may predispose to infection because of poor sinus or middle ear ventilation. Conversely, certain forms of infective rhinitis, such as that caused by the human immune deficiency virus (HIV) can lead to allergy since the gp120 subunit predisposes to Th-2 (T helper lymphocyte-2) cell formation.