Abstract: Objective To explore the laboratory strengthens and clinical value of digital polymerase chain reaction (dPCR) in patients with severe pneumonia. Methods A total of 93 patients with severe pneumonia admitted to the intensive care unit (ICU) at the Central Hospital Affiliated to Shandong First Medical University from March 2021 to May 2023 were selected and broncho-alveolar lavage fluid was sampled. Both dPCR and classic culture method were performed simultaneously. A retrospective analysis was conducted to evaluate the strengthens of the methodology and clinical value of dPCR in patients with severe pneumonia. Results Pathogen detection showed a higher positive rate by dPCR as compared to the classic method (P＜0.05); Specifically, the positive detection rate of Gram-positive bacteria was significantly higher than that of classic bacteria culture(P＜0.05). Furthermore, dPCR was significantly superior to conventional culture in detecting ≥2 pathogens(all P＜0.001). The McNemar′s test indicated that the positive rate of dPCR alone was significantly higher than that of routine culture(P＜0.001). Conclusions Dihiysl PCR method shows a higher sensitivity than classic bacteria culture in pathogen detection, especially used for the samples from multiple pathogens infections, so is of great value in guiding clinical adjustments to antibiotic therapy.

Key words: digital PCR, severe pneumonia, pathogen detection, mixed infection