Corticosteroids for severe community-acquired pneumonia: a story without an ending

Identifying subgroup of severe community-acquired pneumonia based on clinical metagenomics, a multicenter retrospective cohort study

Objective

Severe community-acquired pneumonia (sCAP) is one of the major diseases within the ICU. We hypothesize that subtyping sCAP based on simple inflammatory markers, organ dysfunction, and clinical metagenomics results is feasible.

Method

In this study, we retrospectively enrolled immunocompetent sCAP patients requiring invasive mechanical ventilation, who underwent clinical metagenomics from 17 medical centers. We collected data on potentially pathogenic species reported by clinical metagenomics and clinical information for all patients. Latent class analysis (LCA) was applied to routine clinical parameters such as gender, age, white blood cell (WBC), lymphocytes, C-reactive protein (CRP), and Procalcitonin (PCT), identifying two optimally fitting models.

Results

A total of 569 patients were enrolled. Compared to class B, class A was characterized by a younger age, higher CRP and PCT levels, and a higher incidence of coagulation dysfunction, liver failure, circulatory failure, and renal failure. However, the mortality rates were similar between the two groups. In class A, more cases of Streptococcus spp. and fewer cases of HSV-1 and Candida spp. were detected. Among the patients in the two phenotypes, 48.7% and 57.5% received corticosteroid treatment, respectively. In the class A, corticosteroid treatment was not associated with patient mortality (unadjusted hazard ratio (HR)=0.988; 95% confidence interval (CI), 0.634-1.541; p=0.959). In contrast, in the class B group, the use of corticosteroids was associated with a reduced mortality rate (adjusted HR=0.719; 95% CI, 0.525-0.986; p=0.04). Additional analysis showed that in class B, methylprednisolone was associated with reduced mortality (adjusted HR=0.61; 95% CI, 0.44-0.86; p=0.005), while dexamethasone was not associated with mortality (adjusted HR=1.4; 95% CI, 0.89-2.22; p=0.148). In addition, after dose conversion, the results showed that higher doses of corticosteroids in class B were associated with increased mortality (adjusted HR=1.01; 95% CI, 1.00-1.01; p=0.005).

Conclusion

We identified two classes based on clinical metagenomics and clinical features. Class B exhibited a better response to corticosteroid compared to class A. The rapid identification of these phenotypes could facilitate the screening of sCAP patients responsive to corticosteroid in future prospective clinical trials.

Corticosteroid in non-COVID-19 induced community-acquired pneumonia, a meta-analysis

BACKGROUND

Corticosteroid treatment in non-COVID-19 induced Community-acquired pneumonia (CAP) remains inconclusive.

OBJECTIVES

We aimed to assess the role of corticosteroid treatment in CAP.

METHODS

We conducted a comprehensive search of online databases, including PubMed, Embase, and Cochrane, to identify articles published from January 1, 2000, to May 5, 2023. Double-blind RCTs were selected. Two authors screened studies and extracted data. The evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach.

RESULTS

We analyzed data from 12 RCTs, involving 2446 patients. Corticosteroids therapy may reduce short-term mortality in patients with severe CAP (sCAP) and shorten the hospital length of stay in patients with CAP. Furthermore, corticosteroids treatment can decrease the risk of requiring mechanical ventilation, developing septic shock and multiple organ dysfunction syndrome (MODS). There were no significant differences between the corticosteroid and control groups concerning gastrointestinal bleeding and nosocomial infection. The use of corticosteroids could increase the risk of hyperglycemia.

CONCLUSION

Corticosteroid treatment for sCAP has the potential to provide benefits in reducing short-term mortality, but this conclusion necessitates more evidence. Besides, we found no evidence that strongly prevents us from using corticosteroids in patients with sCAP or those at risk of progressing to sCAP.

Pediatric adenovirus pneumonia: clinical practice and current treatment

Adenovirus pneumonia is common in pediatric upper respiratory tract infection, which is comparatively easy to develop into severe cases and has a high mortality rate with many influential sequelae. As for pathogenesis, adenoviruses can directly damage target cells and activate the immune response to varying degrees. Early clinical recognition depends on patients' symptoms and laboratory tests, including those under 2 years old, dyspnea with systemic toxic symptoms, atelectasis or emphysema in CT image, decreased leukocytes, and significantly increased C-reaction protein (CRP) and procalcitonin (PCT), indicating the possibility of severe cases. Until now, there is no specific drug for adenovirus pneumonia, so in clinical practice, current treatment comprises antiviral drugs, respiratory support and bronchoscopy, immunomodulatory therapy, and blood purification. Additionally, post-infectious bronchiolitis obliterans (PIBO), hemophagocytic syndrome, and death should be carefully noted. Independent risk factors associated with the development of PIBO are invasive mechanical ventilation, intravenous steroid use, duration of fever, and male gender. Meanwhile, hypoxemia, hypercapnia, invasive mechanical ventilation, and low serum albumin levels are related to death. Among these, viral load and serological identification are not only "gold standard" for adenovirus pneumonia, but are also related to the severity and prognosis. Here, we discuss the progress of pathogenesis, early recognition, therapy, and risk factors for poor outcomes regarding severe pediatric adenovirus pneumonia.