关键词: 肺梗死, 肺血栓栓塞症, 中高危风险, 误诊, 肺炎, 预测

Abstract: Background Despite the increasing number of reports on pulmonary infarction secondary to pulmonary embolism in recent years, misdiagnosis remains common, mainly as pneumonia. Especially in patients with intermediate and high-risk pulmonary embolism, delays in diagnosis and treatment would lead to poor prognosis. Objective To summarize the clinical characteristics and related risk factors of patients with pulmonary infarction secondary to intermediate and high-risk pulmonary embolism misdiagnosed as pneumonia. and construct an early diagnostic model. Methods This retrospective study included patients with pulmonary embolism hospitalized at the First Affiliated Hospital of USTC from January 2017 to December 2023. We analyzed clinical characteristics of patients with intermediate to high-risk pulmonary infarction secondary to pulmonary embolism who were misdiagnosed as pneumonia and compared the differences between the misdiagnosed groups and control group. Furthermore, we explored the independent predictive factors for delayed diagnosis using multivariate logistic regression analysis, and to analyze the predictive value of various indicators for the misdiagnosis by ROC curves and compare the AUC values using Delong test. Results Among 101 cases of pulmonary infarction secondary to intermediate-risk and high-risk pulmonary embolism, 70 of them were very misdiagnosed as pneumonia. Patients in the misdiagnosed group were older, have a higher incidence of fever and chest pain, and unlikely presented dyspnea compared with the control group. The percentage of misdiagnosed gradually decreased from 2017 to 2023 (100.0%, 83.3%, 74.1%, 71.4%, 63.2%, 66.7%, and 50.0%). The results of multivariate logistic regression analysis showed that age ≥ 60 years old [OR=18.271, 95% CI (4.373, 76.339), P<0.001], fever [OR=16.073, 95% CI (3.510, 73.786), P<0.001], chest pain [OR=6.660, 95% CI (1.571, 28.233), P=0.010], and without dyspnea [OR=9.027, 95% CI (2.049, 30.249), P=0.003] were independent predictive factors for the misdiagnosis. Multivariate joint model=-6.624+0.095x age+2.510x fever+2.683x without respiratory distress, AUC under the curve=0.880 [95% CI (0.802, 0.959), P<0.001], best cutoff value 0.854, sensitivity 0.871, specificity 0.806. The predictive value is superior to single factor indicators such as age (Z=2.771, P=0.006), fever (Z=4.653, P<0.001), and without dyspnea (Z=4.014, P<0.001). Conclusion Although the misdiagnosis rate of pulmonary infarction has decreased in recent years. Clinicians should keep alert to the differential diagnosis of pulmonary infarction and pneumonia when elderly patients present with fever and chest pain but no dyspnea.

Key words: Pulmonary infarction, Pulmonary thromboembolism, Intermediate-risk and high-risk, Misdiagnosis, Pneumonia, Prediction