Asthma with normal lung function

Introduction : Asthma is a chronic inflammatory disease of the airways leading to reversible bronchial obstruction. The demonstration of this obstruction and its reversibility by spirometry is a fundamental but not obligatory element in the diagnosis. Méthodes: We report a retrospective study of 356 cases of asthmatic patients with normal initial lung function and whose diagnosis of asthma was retained at the clinical stage, followed up at the allergology consultation of CHU Ibn Rochd between 2014 and 2023. They represented 60% of all asthmatics. Results : There was a clear female predominance (85%), with an average age of 25 years (11 - 52 years). Obesity and gastro-oesophageal reflux were noted in 36% of cases each, and diabetes in 14%. Associated rhinitis was noted in 52% of cases, conjunctivitis in 35% and urticaria in 26%. Functional parameters improved with β2-mimetics in 47% of cases, with no obstructive ventilatory disorders. The mean FEV1 was 94% and the mean Tiffeneau ratio 83%. Skin tests performed in 45% of cases were positive in 93%. Inhaled corticosteroid therapy combined with a long-acting bronchodilator was prescribed in 61% of patients. Anti-leukotrienes were prescribed in 33% of cases. Asthma was controlled in 73% of cases and uncontrolled in 27%. Progression was stationary in the majority of cases, with control maintained. <bold>Conclusion:</bold> In this study, we emphasize that normal spirometry cannot rule out the diagnosis of asthma at the clinical stage. Rather, it is necessary for monitoring purposes.