Local Allergic Rhinitis
Local allergic rhinitis (LAR) is an independent special form of allergic rhinitis that has only become better known and described in recent years. It is called this way because the immunological reaction here is limited to the nasal mucosa.
Therefore, neither a positive reaction in the prick test nor specific immunoglobulin E (IgE) against airborne allergens (pollen, house dust mite, animal or mould allergens) can be detected in the blood. In the nasal provocation test, however, a positive reaction to the responsible allergen can usually be triggered. In addition, increased levels of specific IgE and inflammatory messengers can be detected in the nasal secretions of affected persons. The nasal provocation test is therefore the standard diagnostic procedure for the detection of LAR. House dust mites are the most common allergens to be detected.
The symptoms are the same as in allergic rhinitis. However, LAR is more likely to be moderate to severe. In the long term, the symptoms tend to worsen and the risk of developing bronchial asthma is increased. Both often lead to a significant loss of quality of life.
Local allergic rhinitis should be considered as an alternative diagnosis for typical symptoms of allergic rhinitis, in cases, where the usual allergy tests have been negative.
There are no reliable figures on the frequency of local allergic rhinitis in the population as a whole as it has not yet been recognised as an independent clinical picture. It is assumed that the number of unreported cases is relatively high. According to epidemiological estimates, about a quarter of all patients with rhinitis (including non-allergic forms) are affected and up to a maximum of half of patients with general allergic rhinitis. In addition, younger people and women seem to be affected more frequently than men. There is also evidence that LAR often begins in childhood.
Treatment is the same as for allergic rhinitis. Specific immunotherapy (hyposensitisation) has also been shown to be effective.