Pulmonary barotrauma incidence and risk factors in non-HIV PCP patients

Pulmonary barotrauma is a severe complication of Pneumocystis jirovecii pneumonia (PJP), yet its prognostic significance in non-human immunodeficiency virus (HIV) infection populations remains uncharacterized. The aim of this study was to analyze the incidence and associated risk factors of pulmonary barotrauma in non-HIV patients with PJP. We retrospectively reviewed all non-HIV PJP patients admitted to our hospital from January 2009 to December 2024. Patients were divided into two groups based on whether they developed barotrauma. Through multivariate binary regression analysis, independent risk factors for the occurrence of barotrauma were identified and a predictive model was developed. Among 334 patients, 40 (12.0%) developed barotrauma: pneumothorax (n = 23) and isolated subcutaneous emphysema or pneumomediastinum (n = 17). Barotrauma patients had higher rates of intensive care unit admission (85.0% vs. 37.4%), invasive mechanical ventilation (75.0% vs. 20.7%), and mortality (72.5% vs. 23.8%). They also had a higher proportion of patients with a smoking history (50.0% vs. 33.7%). Admission labs showed elevated white blood cell count (8.7 vs. 7.4 × 109/L), lactate dehydrogenase (506 vs. 383 IU/L), C-reactive protein (63.68 vs. 50.12 mg/L), 1,3-β-D-glucan (312.98 vs. 156.32 pg./mL), and bronchoalveolar lavage fluid neutrophils (53.0% vs. 20.5%), along with reduced albumin (28.3 vs. 30.6 g/L) and oxygenation index (PaO2/FiO2 ratio) (165.52 vs. 266.67 mmHg). Multivariable binary logistic regression identified PaO2/FiO2 as an independent predictor of barotrauma (OR = 0.993, 95% CI 0.989–0.998, p = 0.003). The final multivariable model demonstrated good discriminative performance, yielding an area under the curve of 0.751 (95% CI 0.674–0.828). In non-HIV PJP, pulmonary barotrauma is not only common but also strongly associated with critical illness and mortality. Impaired oxygenation at admission independently predicts its occurrence. This finding provides a clinically applicable model that may enable earlier risk stratification and guide closer monitoring and management in high-risk patients.