Specific pathogens as predictors of poor long-term prognosis after hospital discharge for community-acquired pneumonia

Microbial dynamics, risk factors and outcomes of secondary pneumonia in critically ill patients with COVID-19: A multicenter retrospective cohort study

BACKGROUND

Secondary pneumonia has a significant clinical impact on critically ill patients with COVID-19.

AIM

Considering potential geographic variations, this study explores the clinical implications of secondary pneumonia within East Asian populations.

METHODS

This multicenter, retrospective cohort study enrolled critical COVID-19 patients requiring intensive care units (ICUs) admission in Taiwan from December 31, 2020, to June 1, 2022.

FINDINGS

Among the 187 critical COVID-19 patients, 80 (42.8%) developed secondary pneumonia. The primary causative pathogens were gram-negative bacilli (GNB) (76.8%). Gram-positive cocci and fungi were mainly observed during the initial two weeks of ICU stay. Notably, the incidence of pulmonary aspergillosis was 9.2% during the first week of ICU stay and all Staphylococcus aureus were susceptible to methicillin. Multi-drug resistant organisms (MDROs) were responsible for 28.3% of the cases, exhibiting significantly longer ICU stays compared to the non-MDRO group (median, 27 vs. 14 days, P < 0.001). In the multivariate analysis, Acute Physiology and Chronic Health Evaluation II (APACHE II) and Sequential Organ Failure Assessment (SOFA) scores were associated with a significantly increased risk of secondary pneumonia. In-hospital mortality was significantly higher in patients with secondary pneumonia than in those without (37.7% vs. 16.7%, P = 0.02) and survival analysis demonstrated gram-negative bacilli-related secondary pneumonia contributed to a worse prognosis.

CONCLUSIONS

Secondary pneumonia in critical COVID-19 patients significantly raised in-hospital mortality and extended hospital and ICU stays. Moreover, the presence of GNB notably predicted an unfavorable prognosis.

Acute organ injury and long-term sequelae of severe pneumococcal infections

Streptococcus pneumoniae (Spn) is a major public health problem, as it is a main cause of otitis media, community-acquired pneumonia, bacteremia, sepsis, and meningitis. Acute episodes of pneumococcal disease have been demonstrated to cause organ damage with lingering negative consequences. Cytotoxic products released by the bacterium, biomechanical and physiological stress resulting from infection, and the corresponding inflammatory response together contribute to organ damage accrued during infection. The collective result of this damage can be acutely life-threatening, but among survivors, it also contributes to the long-lasting sequelae of pneumococcal disease. These include the development of new morbidities or exacerbation of pre-existing conditions such as COPD, heart disease, and neurological impairments. Currently, pneumonia is ranked as the 9^th leading cause of death, but this estimate only considers short-term mortality and likely underestimates the true long-term impact of disease. Herein, we review the data that indicates damage incurred during acute pneumococcal infection can result in long-term sequelae which reduces quality of life and life expectancy among pneumococcal disease survivors.

Clinical profile analysis and nomogram for predicting in-hospital mortality among elderly severe community-acquired pneumonia patients with comorbid cardiovascular disease: a retrospective cohort study

Background

Researchers have linked cardiovascular disease (CVD) with advancing age; however, how it drives disease progression in elderly severe community acquired pneumonia (SCAP) patients is still unclear. This study aims to identify leading risk predictors of in-hospital mortality in elderly SCAP patients with CVD, and construct a comprehensive nomogram for providing personalized prediction.

Patients and methods

The study retrospectively enrolled 2365 elderly patients identified SCAP. Among them, 413 patients were found to have CVD. The LASSO regression and multivariate logistic regression analysis were utilized to select potential predictors of in-hospital mortality in elderly SCAP patients with CVD. By incorporating these features, a nomogram was then developed and subjected to internal validations. Discrimination, calibration, and clinical use of the nomogram were assessed via C-index, calibration curve analysis, and decision plot.

Results

Compared with patients without CVD, elderly SCAP patients with CVD had a significant poor outcome. Further analysis of the CVD population identified 7 independent risk factors for in-hospital mortality in elderly SCAP patients, including age, the use of vasopressor, numbers of primary symptoms, body temperature, monocyte, CRP and NLR. The nomogram model incorporated these 7 predictors showed sufficient predictive accuracy, with the C-index of 0.800 (95% CI 0.758–0.842). High C-index value of 0.781 was obtained in the internal validation via bootstrapping validation. Moreover, the calibration curve indicative a good consistency of risk prediction, and the decision curve manifested that the nomogram had good overall net benefits.

Conclusion

An integrated nomogram was developed to facilitate the personalized prediction of in-hospital mortality in elderly SCAP patients with CVD.