Clinical prognostic significance of serum high mobility group box-1 protein in patients with community-acquired pneumonia

Effectiveness of macrolides as add-on therapy to beta-lactams in community-acquired pneumonia: A meta-analysis of randomized controlled trials

PURPOSE

This study aims to evaluate whether adding macrolides (MAC) to beta-lactam (BL) monotherapy in the treatment of community-acquired pneumonia (CAP) offers clinical benefits that justify the potential disadvantages or side effects.

METHODS

We systematically searched PubMed, Embase, and Cochrane for randomized controlled trials (RCTs) comparing BL monotherapy to combination therapy with BL and MAC for the in-hospital treatment of CAP. We pooled mean differences (MD) for continuous outcomes and risk ratio (RR) for binary outcomes, with 95% confidence intervals (CI).

RESULTS

Six RCTs with 2661 participants (52% receiving combination therapy), revealed no significant difference in in-hospital mortality (RR 0.99; 95% CI 0.78 to 1.25; p = 0.94; I2 = 0%), 90-day mortality (RR 1.03; 95% CI 0.82 to 1.29; p = 0.83; I2 = 13%), or 30-day mortality (RR 0.90; 75% CI 0.63 to 1.29; p = 0.58; I2 = 54%). Additionally, no significant differences were observed in the length of hospital stay (MD 0.51; 95% CI - 0.50 to 1.51; p = 0.33; I2 = 63%) or respiratory insufficiency (RR 0.63; 95% CI 0.29 to 1.35; p = 0.24; I2 = 74%). However, combination therapy significantly improved the treatment success rate (RR 1.17; 95% CI 1.04 to 1.32; p = 0.009; I2 = 0%).

CONCLUSION

Our findings suggest that BL + MAC therapy should not be used in all cases of hospitalized patients with CAP.

PROSPERO ID

CRD42024516383 - Data of registration: 03/03/2024.

Veno-venous extracorporeal membrane oxygenation in devastating bacterial pneumonia: a case report and review of the literature

BACKGROUND

Bacterial pneumonia is one of the most common causes of acute respiratory distress syndrome. In fulminant cases, when mechanical ventilation fails, veno-venous extracorporeal membrane oxygenation is required. However, this method is still associated with significant mortality and a wide range of potential complications. However, there are now many case reports of good outcomes even in patients with prolonged extracorporeal oxygenation, as in our rather complicated case report.

CASE PRESENTATION

Our case report describes a complicated but successful treatment of a severe, devastating bacterial pneumonia in a 39-year-old European polymorbid woman with a rare form of diabetes mellitus, which had been poorly compensated for a long time with limited compliance, in the context of a combined immunodeficiency that strongly influenced the course of the disease. The patient's hospitalization required a total of 30 days of veno-venous extracorporeal membrane oxygenation therapy and more than 50 days of mechanical ventilation. Numerous complications, particularly bleeding, required seven chest drains, two extracorporeal membrane oxygenation circuit changes, and one surgical revision. The patient's mental state required repeated psychiatric intervention.

CONCLUSION

It is possible that even the initially severely damaged lung parenchyma can develop its regenerative potential if suitable conditions are provided for this process, including a sufficiently long period of extracorporeal membrane oxygenation. We believe that this case report may also contribute to the consideration of the indications and contraindications of extracorporeal support. The authors also discuss the limitations and risks of prolonged veno-venous extracorporeal membrane oxygenation support and periprocedural anticoagulation strategies.

Immunomodulation of susceptibility to pneumococcal pneumonia infection in mouse lungs exposed to carbon nanoparticles via dysregulation of innate and adaptive immune responses

Carbon nanotubes (CNTs) are emerging pollutants of occupational and environmental health concern. While toxicological mechanisms of CNTs are emerging, there is paucity of information on their modulatory effects on susceptibility to infections. Here, we investigated cellular and molecular events underlying the effect of multi-walled CNT (MWCNT) exposure on susceptibility to Streptococcus pneumoniae infection in our 28-day sub-chronic exposure mouse model. Data indicated reduced phagocytic function in alveolar macrophages (AMs) from MWCNT-exposed lungs evidenced by lower pathogen uptake in 1-h infection assay. At 24-h post-infection, intracellular pathogen count in exposed AMs showed 2.5 times higher net increase (2-fold in vehicle- versus 5-fold in MWCNT-treated), indicating a greater rate of intracellular multiplication and/or survival due to MWCNT exposure. AMs from MWCNT-exposed lungs exhibited downregulation of pathogen-uptake receptors CD163, Phosphatidyl-serine receptor (Ptdsr), and Macrophage scavenger receptors class A type 1 (Msr1) and type 2 (MSr2). In whole lung, MWCNT exposure shifted the macrophage polarization state towards the immunosuppressive phenotype M2b and increased the CD11c+ dendritic cell population required to activate the adaptive immune response. Notably, the MWCNT pre-exposure dysregulated T-cell immunity, evidenced by diminished CD4 and Th17 response, and exacerbated Th1 and Treg responses (skewed Th17/Treg ratio), thereby favoring the pneumococcal infection. Overall, these findings indicated that MWCNT exposure compromises both innate and adaptive immunity leading to diminished host lung defense against pneumonia infection. To our knowledge, this is the first report on an immunomodulatory role of CNT pre-exposure on pneumococcal infection susceptibility due to dysregulation of both innate and adaptive immunity targets.

Pathogen characteristics, changes in inflammation levels, and risk factors for ventilator-associated pneumonia in elderly patients with gastric cancer after surgery

BACKGROUND

Ventilator-associated pneumonia is a common complication in mechanically ventilated patients. Elderly patients with gastric cancer have decreased physical skills and become susceptible to ventilator-associated pneumonia, causing adverse effects, and understanding of the composition of pathogenic bacteria, inflammation level, and risk factors for such patients can provide a basis for disease prevention, diagnosis, and treatment. It is conjectured that Gram-negative bacteria are the main pathogens of postoperative ventilator-associated pneumonia in elderly gastric cancer patients, and they are associated with procalcitonin (PCT), interleukin-8 (IL-8), and high mobility group box 1 protein (HMGB1) as the influencing factors of infection.

AIM

To explore the etiological characteristics, changes in inflammation levels, and risk factors for ventilator-associated pneumonia in elderly patients after surgery for gastric cancer.

METHODS

Fifty-two patients with ventilator-associated pneumonia after gastric cancer surgery at our hospital from August 2017 to August 2021 were selected as a study group, and 78 patients without ventilator-associated pneumonia after surgery in the same period were selected as a control group. The distribution characteristics of pathogenic bacteria and serum inflammatory indexes (PCT, IL-8, and HMGB1) in the study group, control group, and patients with different types of infections in the study group were analyzed. The risk factors associated with ventilator-associated pneumonia in elderly patients with gastric cancer after surgery were identified by Logistic regression analysis.

RESULTS

The percentages of patients who were older than 70 years, underwent mechanical ventilation for more than 5 d, used more than two types of antibiotics, and had a serum albumin level ≤ 30 g/L, basic lung disease, and smoking history, as well as serum PCT, IL-8, and HMGB1 levels were significantly higher in the study group than in the control group (P < 0.05). Logistic regression analysis showed that age > 70 years, mechanical ventilation time > 5 d, serum albumin level ≤ 30 g/L, underlying lung disease, PCT level > 1.0 μg/L, IL-8 level > 15.5 ng/L, and HMGB1 level > 60.0 pg/mL were risk factors for ventilator-associated pneumonia in elderly patients after gastric cancer surgery (P < 0.05). A total of 82 strains of pathogenic bacteria were isolated from 52 patients in the study group. The main strains were Gram-negative bacteria (54 strains, 65.85%). Serum PCT, IL-8, and HMGB1 levels in patients infected with Gram-negative bacteria in the study group were significantly higher than those of patients infected with Gram-positive bacteria and patients with fungal infections, and in patients infected with Gram-positive bacteria than in those with fungal infections (P < 0.05).

CONCLUSION

The pathogens of ventilator-associated pneumonia in elderly patients after gastric cancer surgery are mainly Gram-negative bacteria. Serum PCT, IL-8, and HMGB1 levels can be significantly increased after infection, and their levels are related to the type of pathogens and are important risk factors for ventilator-associated pneumonia.

Clinical Phenotypes and Mortality Biomarkers: A Study Focused on COVID-19 Patients with Neurological Diseases in Intensive Care Units

Purpose: To identify clinical phenotypes and biomarkers for best mortality prediction considering age, symptoms and comorbidities in COVID-19 patients with chronic neurological diseases in intensive care units (ICUs). Subjects and Methods: Data included 1252 COVID-19 patients admitted to ICUs in Cuba between January and August 2021. A k-means algorithm based on unsupervised learning was used to identify clinical patterns related to symptoms, comorbidities and age. The Stable Sparse Classifiers procedure (SSC) was employed for predicting mortality. The classification performance was assessed using the area under the receiver operating curve (AUC). Results: Six phenotypes using a modified v-fold cross validation for the k-means algorithm were identified: phenotype class 1, mean age 72.3 years (ys)-hypertension and coronary artery disease, alongside typical COVID-19 symptoms; class 2, mean age 63 ys-asthma, cough and fever; class 3, mean age 74.5 ys-hypertension, diabetes and cough; class 4, mean age 67.8 ys-hypertension and no symptoms; class 5, mean age 53 ys-cough and no comorbidities; class 6, mean age 60 ys-without symptoms or comorbidities. The chronic neurological disease (CND) percentage was distributed in the six phenotypes, predominantly in phenotypes of classes 3 (24.72%) and 4 (35,39%); χ² (5) 11.0129 p = 0.051134. The cerebrovascular disease was concentrated in classes 3 and 4; χ² (5) = 36.63, p = 0.000001. The mortality rate totaled 325 (25.79%), of which 56 (17.23%) had chronic neurological diseases. The highest in-hospital mortality rates were found in phenotypes 1 (37.22%) and 3 (33.98%). The SSC revealed that a neurological symptom (ageusia), together with two neurological diseases (cerebrovascular disease and Parkinson's disease), and in addition to ICU days, age and specific symptoms (fever, cough, dyspnea and chilliness) as well as particular comorbidities (hypertension, diabetes and asthma) indicated the best prediction performance (AUC = 0.67). Conclusions: The identification of clinical phenotypes and mortality biomarkers using practical variables and robust statistical methodologies make several noteworthy contributions to basic and experimental investigations for distinguishing the COVID-19 clinical spectrum and predicting mortality.