Unlocking the potential of bronchoalveolar lavage: a promising supplement therapy for moderate-to-severe allergic asthma

Bronchoalveolar lavage holds potential therapeutic value for moderate-to-severe asthma that is poorly controlled with standard nebulizer therapy. To evaluate the efficacy and safety of bronchoalveolar lavage (BAL) as an adjunctive therapy in patients with moderate-to-severe allergic asthma inadequately controlled by standard inhaled corticosteroids and long-acting beta₂-agonists therapy. In this retrospective study conducted between July 2021 and December 2024, eligible patients were allocated to a control group receiving standard high-pressure nebulizer therapy or a study group receiving additional BAL. Outcomes included changes in asthma symptom scores, pulmonary function, fractional exhaled nitric oxide (FeNO) levels, adverse events, and bronchoalveolar lavage fluid pathogen distribution. The study group demonstrated significantly greater improvement in subjective symptom scores and small airway function parameters compared to controls ( P < 0.05). This superiority was particularly pronounced in a predefined subgroup with more severe impairment (FEV1% pred < 50%, FVC% pred < 80%, FEV1/FVC < 65%). No significant differences were observed in FeNO levels or overall adverse event incidence ( P > 0.05). BALF analysis in 72 study patients identified 43 distinct pathogens (detection rate: 39.8%), predominantly bacterial species (72.1%). Adjunctive BAL significantly improved lung function, especially in small airways, without increasing adverse reactions, demonstrating a favorable safety profile in patients with uncontrolled allergic asthma, supports BAL’s potential as a therapeutic procedure.