2.2 Methods
The study was performed in accordance with the Declaration of Helsinki and approved by the ethics committee of the Tianjin Children’s Hospital. The ethics committee waived the need for written informed consent provided by participants due to the retrospective nature of the study, because all patient data were analyzed anonymously, and no additional informed consent was required.
Clinical characteristics, laboratory findings, imaging features, and management of the 269 patients were collected at the time of admission.
Peripheral blood samples were also obtained on admission for the determination of blood routine examination, erythrocyte sedimentation rate(ESR), C-reactive protein (CRP), procalcitonin (PCT), interleukin (IL)-6, lactic acid(LA), lactic dehydrogenase (LDH), alanine aminotransferase (ALT), aspartate aminotransferase (AST), ferritin (FER), D- dimer, fibrinogen (FG) and specific antibody to MP. Blood routine examination was performed every 2–3 days and was compared between at admission and at discharge. Chest computed tomography (CT) was performed before admission or during hospitalization as these patients showed persistent fever or large infiltration on chest X-ray.
All the patients enrolled in our study received FOB, and the fluid of BAL were collected for microbiological determination according to theGuide to pediatric bronchoscopy 12. Virus were identified by direct immunofluorescence PCR, MP using PCR and bacteria were detected by culture or multiplex PCR for respiratory bacteria pathogens.
The study was performed in accordance with the Declaration of Helsinki and approved by the ethics committee of the Tianjin Children’s Hospital. The ethics committee waived the need for written informed consent provided by participants due to the retrospective nature of the study, because all patient data were analyzed anonymously, and no additional informed consent was required.