[Criteria for evaluating specific desensitization in asthma]

In the absence of any satisfactory immunological criteria an objective assessment of the results of desensitization in asthma largely rests on clinical criteria. The use of clinical criteria themselves runs into many difficulties, some of which are inherent in the nature of asthma (chronic cause, temporary variations, variations according to the allergen responsible, the association of non-specific factors to specific allergic factors) and others result from the individual characters of the asthmatic under-study. The assessment of the results of desensitization should not rest solely on the observations of the patient and physician. A clinical score can be gathered thanks to a daily diary card. A drug score can be assessed by a daily record of the amount of medication used. The recording of peak flow in spite of its imperfections is particularly well suited to multiple daily measurements of airflow obstruction. The paper work generated by the daily diary cards can be computerised. A study of the correlations existing between the different daily scores recorded shows, that the selection of patients for a trial of desensitization should be carried out over a long enough period to enable non compliant patients to be discarded namely those patients without any good correlation between the symptoms and functional score. Another approach to assessing the efficacy of desensitization is the study of changes in bronchial provocation tests to allergens; these depend on a good reproducibility of the immediate and delayed responses to allergens in each subject at different times.