Diagnostic value of bronchoalveolar lavage fluid YKL-40 and HMGB1 for assessing disease severity and prognosis in ventilator-associated pneumonia

Lang Haijing; Di Hong; Che Na; An Jiaxin; Wang Qin; Wu Chenyang; Zhang Fan; Li Mengyun

doi:10.11986/j.issn.1673-873X.2025.03.09

Abstract：Objective To investigate the diagnostic value of bronchoalveolar lavage fluid chitinase-3-like protein 1(YKL-40)and high-mobility group box-1(HMGB1)in assessing disease severity and prognosis in patients with ventilator-associated pneumonia(VAP).Methods A total of 110 patients who developed VAP after mechanical ventilation at a hospital in Hebei Province from June 2021 to June 2024 were selected as the study participants.Levels of YKL-40 and HMGB1 in bronchoal-veolar lavage fluid were measured,and the Clinical Pulmonary Infection Score(CPIS)and Acute Physiology and Chronic Health Evaluation Ⅱ(APACHE Ⅱ)score were assessed.Patients were allocated to mild(n=38),moderate(n=45),and severe(n=27)groups based on disease severity.Pearson correlation analysis was used to explore the relationship between bronchoalveolar lavage fluid YKL-40 and HMGB1 levels and CPIS and APACHE Ⅱ scores.Based on the 28-day prognosis,patients were assigned to survival(n=79)and death(n=31)groups.Receiver operating characteristic(ROC)curve analy-sis was used to evaluate the predictive value of bronchoalveolar lavage fluid YKL-40 and HMGB1 levels for VAP prognosis.Multivariate stepwise logistic regression analysis was used to identify influencing factors for VAP prognosis.Results As disease severity increased,levels of YKL-40 and HMGB1 in bronchoalveolar lavage fluid and CPIS scores in VAP patients gradually increased(P<0.05).Levels of YKL-40 and HMGB1 in bronchoalveolar lavage fluid were positively correlated with CPIS and APACHE Ⅱ scores in VAP patients(P<0.001).Levels of YKL-40 and HMGB1 in bronchoalveolar lavage fluid were significantly lower in the survival group than in the death group(P<0.05).The areas under the curve(AUC)for predicting VAP prognosis using bronchoalveolar lavage fluid YKL-40 and HMGB1 levels were 0.742(95%CI:0.697-0.792)and 0.829(95%CI:0.784-0.879),respectively,while the AUC for combined prediction was 0.917(95%CI:0.867-0.962).The proportion of patients with mechanical ventilation duration≥7 days,CPIS,APACHE Ⅱ score,and procalcitonin(PCT)level were higher in the death group than in the survival group,and the differences were statistically significant(P<0.05).Multivariate analysis showed that duration of mechanical ventilation(OR=1.876,95%CI:1.096-3.209),CPIS(OR=2.342,95%CI:1.353-4.054),APACHE Ⅱ score(OR=2.547,95%CI:1.509-4.299),PCT(OR=2.199,95%CI:1.398-3.458),YKL-40(OR=2.898,95%CI:1.793-4.684),and HMGB1(OR=3.297,95%CI:1.931-5.630)were influencing factors for VAP prognosis(P<0.05).Conclusion Levels of YKL-40 and HMGB1 in bronchoalveolar lavage fluid increased with worsening pulmonary infection and disease severity in VAP patients and showed high expression in patients with fatal prognosis.They have certain predictive value for VAP prog-nosis,and combined detection has superior predictive value.