Objective: To identify the most useful combinations of symptoms and the results of radioallergosorbent tests (RASTs) and skin prick tests (SPTs) for the diagnosis of allergic rhinitis.
Design: A prospective comparison was made of symptoms and the results of RASTs and SPTs with 7 different nasal allergies; the references used were the "consensus diagnoses" provided by 3 experts.
Setting: Nineteen general practices in The Netherlands.
Patients: 365 consecutive patients aged 12 or over who visited their general practitioner because of chronic or recurrent nasal symptoms between 1 March 1990 and 1 March 1991.
Main outcome measures: The most useful combinations of items from the history, RASTs, and SPTs, for the diagnosis of 7 different nasal allergies; the predictive probabilities of these combinations.
Results: Diagnostic criteria could be drawn up resulting in a near-perfect discrimination between patients diagnosed as having allergic rhinitis and patients diagnosed as not having allergic rhinitis. Most of these criteria combined only a single item from the history with either RAST or SPT. For nearly all nasal allergies, both the negative predictive probabilities and the positive predictive probabilities were 97% or more.
Conclusions: The common nasal allergies can be diagnosed with a very high certainty with the aid of simple diagnostic criteria. Data from a strictly limited case history combined with either RAST or SPT are sufficient.