The impact of Tanreqing injection on mucus hypersecretion and cough in bronchiectasis: A meta-analysis of randomized controlled trials.

Background: Bronchiectasis clinically manifests airway mucus hypersecretion as mucopurulent sputum production and chronic cough. In the past decade, Tanreqing injection (TRQ) has been often used in clinical practice as an add-on treatment for bronchiectasis in China. Several in vivo studies have indicated that TRQ is effective in improving sputum expectoration and cough in acute exacerbation of bronchiectasis but results of individual studies are inconsistent. Therefore, systematically and critically evaluating the effectiveness and safety of TRQ on mucus hypersecretion and cough in bronchiectasis is necessary.

Methods: Randomized controlled trials examining the treatment of bronchiectasis with TRQ were systematically searched from databases including PubMed, Cochrane Library, Embase, Web of Science, Chinese National Knowledge Infrastructure, Vip Information Database, Wanfang data, and Chinese Biomedical Literature Database, based on a preregistered protocol and adhering to Cochrane methods. Pertinent data were taken out from the included studies and a methodological quality assessment was done. R language (version 4.4.1) was used to perform the meta-analysis.

Results: Twenty randomized controlled trials involving 1544 patients were analyzed. The results demonstrated that TRQ significantly improved mucus hypersecretion, shortened the duration of cough and phlegm, reduced symptom scores, and enhanced both forced expiratory volume in 1 second and forced vital capacity. Additionally, TRQ effectively lowered inflammatory markers, including C-reactive protein, procalcitonin, white blood cell count, neutrophil count, interleukin-6, and tumor necrosis factor-alpha. Moreover, TRQ increased the partial pressure of oxygen and decreased carbon dioxide pressure.

Conclusion: The findings suggest that TRQ positively impacts mucus hypersecretion and mucociliary clearance, leading to improvements in sputum production and cough during bronchiectasis exacerbations, without increasing the risk of adverse effects. TRQ may be considered a viable option for managing bronchiectasis and could serve as a novel mucus-modifying agent.