Risk Factor Analysis of Mycoplasma pneumoniae Pneumonia Complicated With Plastic Bronchitis in Children: A Single-Center Retrospective Study.

OBJECTIVE: To investigate the clinical features and risk factors for Mycoplasma pneumoniae pneumonia (MPP) complicated with plastic bronchitis (PB) and to provide a reference for the early diagnosis and treatment of this disease. METHODS: Clinical data from 75 pediatric patients diagnosed with MPP who underwent bronchoscopy at our hospital between June 16 and December 31, 2023, were retrospectively analyzed. Patients were stratified into PB and non-PB groups based on the presence or absence of bronchial cast removal during bronchoscopy. Comparative analysis of clinical characteristics was performed between the two groups. Binary logistic regression analysis was employed to identify risk factors associated with MPP complicated by PB. Additionally, bronchial cast components obtained from the PB group underwent compositional analysis using proteomic techniques via mass spectrometry. RESULTS: The composition ratio of children with fever frequency and a heat course ≥ 10 days in the PB group. The composition ratio, neutrophil ratio, erythrocyte sedimentation rate (ESR) and levels of C-reactive protein, lactate dehydrogenase, procalcitonin (PCT) and D-dimer in children with lung compaction were significantly greater than those in the non-PB group (t = 2.290-3.793, χ2 = 5.548, 5.659, Z = -2.085, p < 0.05). Multivariate logistic regression analysis revealed that the PCT level (OR = 1.071, 95% CI = 1.015-1.130, p < 0.05) and ESR (OR = 1.088, 95% CI = 1.033-1.146, p < 0.05) were risk factors for PB. Protein mass spectrometry showed that the bronchial plastic was rich in fibrinogen. CONCLUSIONS: Compared with children with MPP alone, children with PB have a more intense inflammatory response, and the possibility of MPP with PB should be vigilant when the ESR > 25.20 mm/1 h and PCT > 0.19 μg/L. Bronchial plastics in children with PB contain a large amount of fibrin, which may be related to the abnormal activation of coagulation and fibrinolysis systems caused by inflammation.