Age significantly determined the clinical features and prognosis of the disease. The prognosis was worse in patients older than 60 years, calling for clinicians to pay more attention to patients on this special age.

Severe Community Acquired Pneumonia (SCAP) challenges public health globally. Considerable improvements in molecular pathogen testing emerged in the last few years. Our prospective study combinedly used traditional culture, antigen tests, PCR and mNGS in SCAP pathogen identification with clinical outcomes. From June 2018 to December 2019, we conducted a multi-centre prospective study in 17 hospitals of SCAP patients within 48 hours of emergency room stay or hospitalization in China. All clinical data were uploaded into an online database. Blood, urine and respiratory specimens were collected for routine culture, antigen detection, PCR and mNGS as designed appropriately. Aetiology confirmation was made by the local attending physician group and scientific committee according to microbiological results, clinical features, and response to the treatment. Two hundred seventy-five patients were included for final analysis. Combined detection methods made identification rate up to 74.2% (222/299), while 14.4% (43/299) when only using routine cultures and 40.8% (122/299) when not using mNGS. Influenza virus (23.2%, 46/198), S. pneumoniae (19.6%, 39/198), Enterobacteriaceae (14.6%, 29/198), Legionella pneumophila (12.6%, 25/198), Mycoplasma pneumoniae (11.1%, 22/198) were the top five common pathogens. The in-hospital mortality of patients with pathogen identified and unidentified was 21.7% (43/198) and 25.9% (20/77), respectively. In conclusion, early combined detection increased the pathogen identification rate and possibly benefitted survival. Influenza virus, S. pneumoniae, Enterobacteriaceae was the leading cause of SCAP in China, and there was a clear seasonal distribution pattern of influenza viruses. Physicians should be aware of the emergence of uncommon pathogens, including Chlamydia Psittaci and Leptospira.

As a promising tool, PCR in bronchoalveolar lavage fluid (BALF) has not been accepted as a diagnostic criterion for PJP. We undertook a systematic review of published studies to evaluate the diagnostic accuracy of PCR assays in BALF for PJP. Eligible studies from PubMed, Embase and Web of Science reporting PCR assays in BALF for diagnosing PJP were identified. A bivariate meta-analysis of the method’s sensitivity, specificity, and positive and negative likelihood ratios with a 95% confidence interval (CI) were analyzed. The post-test probability was performed to evaluate clinical usefulness. A summary receiver operating characteristics (SROC) curve was used to evaluate overall performance. Subgroup analyses were carried out to analysis the potential heterogeneity. Sixteen studies published between 1994 and 2012 were included. The summary sensitivity and specificity values (95% CI) of PCR in BALF for diagnosis of PJP were 98.3% (91.3%–99.7%) and 91.0% (82.7%–95.5%), respectively. The positive and negative likelihood ratios were 10.894 (5.569–21.309) and 0.018 (0.003–0.099), respectively. In a setting of 20% prevalence of PJP, the probability of PJP would be over 3-fold if the BALF-PCR test was positive, and the probability of PJP would be less than 0.5% if it was negative. The area under the SROC curve was 0.98 (0.97–0.99). The method of PCR in BALF shows high sensitivity and good specificity for the diagnosis of PJP. However, clinical practice for the diagnosis of PJP should consider the consistent respiratory symptoms, radiographic changes and laboratory findings of the suspected patients.

Bronchiectasis and asthma are common respiratory diseases worldwide. However, the influence of asthma on bronchiectasis remains unclear. The objective of this study is to analyse the effects of asthma on bronchiectasis exacerbation.Data from inpatients diagnosed with bronchiectasis with or without asthma at Shanghai Pulmonary Hospital (Shanghai, China) between January 2013 and December 2014 were retrospectively collected and analysed. 249 patients with only bronchiectasis and 214 patients with both bronchiectasis and asthma were included in the study. Follow-up records were used to evaluate the effect of asthma on bronchiectasis exacerbation.The variables found to be independently associated with bronchiectasis exacerbations were age (OR 1.07, 95% CI 1.03–1.11; p<0.001), duration of symptoms (OR 1.06, 95% CI 1.03–1.09; p<0.001), the presence of asthma (OR 2.6, 95% CI 1.15–5.88; p=0.021), forced expiratory volume in 1 s <50% predicted (OR 4.03, 95% CI 1.75–9.26; p=0.001), isolation ofPseudomonas aeruginosain sputum (OR 2.41, 95% CI 1.00–5.79; p=0.05) and lung lesion extension to more than two lobes (OR 2.73, 95% CI 1.16–6.45; p=0.022).The existence of asthma was associated with an independent increase in risk of bronchiectasis exacerbation.