Prevalence. Based on the anamnesis, this form of the disease is detected in 2-6%, and on the basis of provocative samples, in 8-34% of patients with bronchial asthma . Among patients simultaneously suffering from bronchial asthma, sinusitis and nasal polyps , aspirin intolerance occurs in 30-40%. In women, it is observed about 2 times more often than in men. Aspirin intolerance is familial in nature, the type of inheritance is unknown.
– The pathogenesis of aspirin bronchial asthma has not been fully studied, but the participation of immune mechanisms in it has not been confirmed. According to the most common territory, the disease is caused by an imbalance between the formation of arachidonic acid metabolites .
– Aspirin , indomethacin , ibuprofen , mefenamic acid and other NSAIDs block the metabolism of archidonic acid along the cyclooxygenase pathway. Prostaglandin E causes bronchodilation, and prostaglandin F causes bronchospasm, so the imbalance between them can lead to bronchial asthma. The accumulation of products of the lipoxygenase pathway of arachidonic acid metabolism – leukotriene C , leukotriene D and leukotriene E – also contributes to bronchospasm. The following facts indicate the participation of leukotrienes in the pathogenesis of aspirin bronchial asthma:
– In the pathogenesis of aspirin bronchial asthma, other mechanisms may play a role, for example, the direct effect of aspirin on mast cells.
The clinical picture:
– Aspirin bronchial asthma is usually preceded by year-round rhinitis , which may worsen with aspirin. Rhinitis usually occurs in young and middle age. Then there are nasal polyps , hypertrophic sinusitis , purulent sinusitis , eosinophilia , bronchial asthma . The classic aspirin triad includes aspirin intolerance, nasal polyps and bronchial asthma. Aspirin bronchial asthma can occur without rhinitis, sinusitis, and nasal polyps. Despite the fact that 50% of patients have positive skin tests with different allergens, bronchial attacks usually develop under the influence of immune factors
– Attacks of aspirin bronchial asthma are often severe. Usually they are accompanied by swelling of the mucosa and copious discharge from the nose , conjunctivitis . Sometimes fainting . Attacks of aspirin bronchial asthma require emergency care with the use of corticosteroids for parenteral administration .
– The anamnesis and data of a physical examination with aspirin bronchial asthma does not differ from those with other forms of bronchial asthma. Aspirin intolerance is not always possible to establish during the survey. Nasal polyps in the absence of other manifestations of the aspirin triad cannot serve as a sign of aspirin intolerance.
– Laboratory and instrumental studies. Eosinophilia , eosinophilic infiltration of the nasal mucosa , impaired glucose tolerance are characteristic . Often there are positive provocative tests with methacholine and histamine. Radiography of the sinuses reveals mucosal hypertrophy and nasal polyps. However, all these changes do not serve as pathognomonic signs of aspirin bronchial asthma. Skin tests with aspiril-polylysine are uninformative and are not recommended due to the high risk of anaphylactoid reactions .
– The only reliable way to diagnose aspirin intolerance is a provocative test.
– Patients with asthma , especially requiring constant treatment with corticosteroids or combined with nasal polyps, do not conduct provocative tests. They are advised to avoid the use of aspirin and other NSAIDs .
– It should be remembered that this study is dangerous and can only be carried out by an experienced doctor in an allergology center that has an intensive care unit. It is usually used for research purposes.
Prevention and treatment:
– Patients are advised to avoid the use of drugs containing aspirin and other NSAIDs . They should explain that before using any medicine, you must carefully familiarize yourself with its composition and make sure that it does not contain aspirin. Patients should know other names for aspirin, such as acetylsalicylic acid , salicylic acid acetate .
– Tartrazine , a yellow dye that is part of some foods and drugs, has side effects in 50% of patients with aspirin intolerance. It should be remembered that positive provocative tests with tartrazine are noted in no more than 2.5% of patients with aspirin bronchial asthma. In case of intolerance to tartrazine, the use of foods and medicines painted in yellow or orange should be avoided.
– Treat rhinitis , sinusitis , nasal polyps and bronchial asthma . With aspirin bronchial asthma, it is often necessary to prescribe corticosteroids (inhaled or for systemic use). With the ineffectiveness of the conservative treatment of sinusitis and nasal polyps, an operation is performed. It is shown that surgical treatment of sinusitis and nasal polyps does not cause exacerbation of bronchial asthma and leads to an improvement in the condition of patients.
– If treatment with aspirin or other NSAIDs is necessary, and in the past, complications were noted during their use, conduct a provocative test. Aspirin is prescribed by mouth. With a positive provocative test, some authors recommend desensitization . The effect of desensitization on the course of bronchial asthma and rhinitis in patients with aspirin intolerance is currently being studied.
Forecast. With early detection, prevention and treatment, the prognosis is the same as with other forms of bronchial asthma mediated by non-immune mechanisms. Refusal from aspirin does not lead to a complete recovery, but reduces the frequency of attacks of bronchial asthma.