ObjectiveTo explore the clinical value of next-generation sequencing (NGS) in the diagnosis of Pneumocystis jirovecii pneumonia (PCP).MethodsTwo patients with Pneumocystis jirovecii pneumonia after lung transplantation were detected by NGS in the sputum and bronchoalveolar lavage fluid. The clinical data, imaging features, laboratory examination and treatment of the two patients were reported. A systematic literature review was performed for similar published cases in PubMed database, using the keywords "lung transplantation/solid organ transplantation" and "Pneumocystis jirovecii".ResultsThere were six references based on the keywords of "lung transplantation " and " Pneumocystis jirovecii ", of which three were case report. Sixty-six lung transplant patients were complicated with Pneumocystis jirovecii in total. The clinical manifestations of Pneumocystis jirovecii pneumonia were fever and dyspnea of different degrees. The diffuse "ground glass" infiltration could be shown on imaging. Computer tomography scan of chest was a sensitive method to detect PCP. Combined immunofluorescence microscope/PCR/serum 3-β-D-glucan could effectively improve the accuracy of microbiology detection. In addition, NGS could quickly and accurately identify pathogenic bacteria, give guidance for treatment and improve prognosis so as to benefit patients well. Trimethoprim/sulfamethoxazole (TMP/SMZ) was the preferred choice for the treatment of PCP patients.ConclusionsPneumocystis jirovecii pneumonia is more common in patients with immunodeficiency or immunosuppression. NGS can help rapid and accurate diagnosis, and the treatment should be early and sufficient.