Biomarkers in Pneumonia-Beyond Procalcitonin

C-reactive protein and procalcitonin: As predictor biomarkers of severity and outcome in children with community-acquired pneumonia

Our cohort study aimed to compare serum C-reactive protein (CRP) and procalcitonin (PCT) levels in children with community-acquired pneumonia defined by WHO. The former differentiated between pneumonia and severe pneumonia while the latter was better for the outcome of pneumonia.

Biomarkers associated with vaccine-associated enhanced respiratory disease following influenza A virus infection in swine

Influenza A virus (IAV) is a major pathogen in the swine industry. Whole-inactivated virus (WIV) vaccines in swine are highly effective against homologous viruses but provide limited protection to antigenically divergent viruses and may lead to vaccine-associated enhanced respiratory disease (VAERD) after heterologous infection. Although VAERD is reproducible in laboratory studies, clinical diagnosis is challenging, as it would require both knowledge of prior vaccine history and evidence of severe disease by assessment of pathologic lesions at necropsy following infection with a heterologous virus. The objective of this study was to identify potential biomarkers for VAERD for antemortem clinical diagnosis. Naïve pigs were split into two groups, and one group was vaccinated with IAV WIV vaccine. All pigs were then challenged with a heterologous virus to induce VAERD in the vaccinated group and necropsied at 5 days post infection (dpi). Blood was collected on 0, 1, 3, and 5 dpi, and assessed by hematology, plasma chemistry, acute phase proteins, and citrullinated H3 histone (CitH3) assays. Additionally, cytokine and CitH3 levels were assessed in bronchoalveolar lavage fluid (BALF) collected at necropsy. Compared to nonvaccinated challenged pigs, blood collected from vaccinated and challenged (V/C) pigs with VAERD had elevated white blood cells and neutrophils, elevated C-reactive protein and haptoglobin acute phase proteins, and elevated CitH3. In BALF, the proinflammatory cytokine IL-8 and CitH3 were elevated in V/C pigs. In conclusion, a profile of elevated white blood cells and neutrophils, elevated C-reactive protein and haptoglobin, and elevated CitH3 may be relevant for a clinical antemortem IAV VAERD diagnosis.

miR-486-5p predicted adverse outcomes of SCAP and regulated K. pneumonia infection via FOXO1

PURPOSE

Severe community-acquired pneumonia (SCAP) is a common respiratory system disease with rapid development and high mortality. Exploring effective biomarkers for early detection and development prediction of SCAP is of urgent need. The function of miR-486-5p in SCAP diagnosis and prognosis was evaluated to identify a promising biomarker for SCAP.

PATIENTS AND METHODS

The serum miR-486-5p in 83 patients with SCAP, 52 healthy individuals, and 68 patients with mild CAP (MCAP) patients were analyzed by PCR. ROC analysis estimated miR-486-5p in screening SCAP, and the Kaplan-Meier and Cox regression analyses evaluated the predictive value of miR-486-5p. The risk factors for MCAP patients developing SCAP were assessed by logistic analysis. The alveolar epithelial cell was treated with Klebsiella pneumonia to mimic the occurrence of SCAP. The targeting mechanism underlying miR-486-5p was evaluated by luciferase reporter assay.

RESULTS

Upregulated serum miR-486-5p screened SCAP from healthy individuals and MCAP patients with high sensitivity and specificity. Increasing serum miR-486-5p predicted the poor outcomes of SCAP and served as a risk factor for MCAP developing into SCAP. K. pneumonia induced suppressed proliferation, significant inflammation and oxidative stress in alveolar epithelial cells, and silencing miR-486-5p attenuated it. miR-486-5p negatively regulated FOXO1, and the knockdown of FOXO1 reversed the effect of miR-486-5p in K. pneumonia-treated alveolar epithelial cells.

CONCLUSION

miR-486-5p acted as a biomarker for the screening and monitoring of SCAP and predicting the malignancy of MCAP. Silencing miR-486-5p alleviated inflammation and oxidative stress induced by K. pneumonia via negatively modulating FOXO1.

Human immunoglobulin in combination with antimicrobial agents enhances the treatment efficacy and reduces inflammatory response in children with severe pneumonia

OBJECTIVE

To investigate the efficacy of human immunoglobulin combined with antibiotics in treating severe pediatric pneumonia.

METHODS

A retrospective analysis was performed on 210 pediatric patients with severe pneumonia admitted to the Department of Neonatology of Cangzhou Central Hospital from April 2019 to October 2022. Patients were divided into two groups (the observation group and the control group) based on the administration of human immunoglobulin. Clinical indexes of both groups before and after treatment were analyzed to determine the therapeutic effect of different treatment methods on pediatric severe pneumonia.

RESULTS

The durations of cough, fever, pulmonary rales, and lung shadow, and hospitalization time in the observation group were significantly shorter than those in the control group (all P<0.05). The total clinical effective rate in the observation group was significantly higher than that in the control group (P<0.05). Levels of inflammatory factors (IL-6, IL-8 and hsCRP) were decreased in both groups after treatment (all P<0.05), and were lower in the observation group compared with the control group after treatment (all P<0.05). The serum levels of IgA, IgG and IgM after five days of intervention were obviously higher than those before intervention in the observation group (all P<0.05), but the serum levels of IL-4, INF-γ and INF-γ/IL-4 were obviously lower (all P<0.05). The total incidence of adverse reactions between two groups after intervention was not statistically different (P<0.05).

CONCLUSION

The combination of human immunoglobulin and antibiotics for the treatment of pediatric severe pneumonia is beneficial, because it improves efficacy, boosts the immune system, and reduces inflammation.

Longitudinal metabolite profiling of Streptococcus pneumoniae-associated community-acquired pneumonia

INTRODUCTION

Longitudinal biomarkers in patients with community-acquired pneumonia (CAP) may help in monitoring of disease progression and treatment response. The metabolic host response could be a potential source of such biomarkers since it closely associates with the current health status of the patient.

OBJECTIVES

In this study we performed longitudinal metabolite profiling in patients with CAP for a comprehensive range of metabolites to identify potential host response biomarkers.

METHODS

Previously collected serum samples from CAP patients with confirmed Streptococcus pneumoniae infection (n = 25) were used. Samples were collected at multiple time points, up to 30 days after admission. A wide range of metabolites was measured, including amines, acylcarnitines, organic acids, and lipids. The associations between metabolites and C-reactive protein (CRP), procalcitonin, CURB disease severity score at admission, and total length of stay were evaluated.

RESULTS

Distinct longitudinal profiles of metabolite profiles were identified, including cholesteryl esters, diacyl-phosphatidylethanolamine, diacylglycerols, lysophosphatidylcholines, sphingomyelin, and triglycerides. Positive correlations were found between CRP and phosphatidylcholine (34:1) (cor = 0.63) and negative correlations were found for CRP and nine lysophosphocholines (cor = - 0.57 to - 0.74). The CURB disease severity score was negatively associated with six metabolites, including acylcarnitines (tau = - 0.64 to - 0.58). Negative correlations were found between the length of stay and six triglycerides (TGs), especially TGs (60:3) and (58:2) (cor = - 0.63 and - 0.61).

CONCLUSION

The identified metabolites may provide insight into biological mechanisms underlying disease severity and may be of interest for exploration as potential treatment response monitoring biomarker.

Fibrinolysis Resistance After Injury Is a Risk Factor for a Hospital-Acquired Pneumonia-Like Disease Pattern

Background: Pneumonia is associated with increased morbidity and costs in the intensive care unit (ICU). Its early identification is key for optimal outcomes, but early biomarkers are lacking. Studies suggest that fibrinolysis resistance (FR) after major abdominal surgery is linked to an increased risk of infection. Patients and Methods: Patients in a randomized controlled trial for hemorrhagic shock were evaluated for FR. Fibrinolysis resistance was quantified by thrombelastography with exogenous tissue plasminogen activator (tPA-TEG) at 24- and 48-hours post-injury and measuring LY30 (%). A receiver-operating characteristics (ROC) curve analysis was used to identify a cutoff for increased risk of pneumonia, which was then validated in ICU patients at risk for venous thromboembolism (VTE). Multivariable logistic regression was used to control for confounders. Results: Forty-nine patients in the hemorrhagic shock cohort had tPA-TEGs at 24- and 48-hours (median ISS, 27; 7% pneumonia). A composite tPA-TEG LY30 of less than 4% at 24 and 48 hours was found to be the optimal cutoff for increased risk of pneumonia. This cohort had a seven-fold increased rate of pneumonia (4% vs. 28%; p = 0.048). Eighty-eight patients in the VTE cohort had tPA-TEGs at 24 and 48 hours post-ICU admission (median ISS, 28; 6% pneumonia). The tPA-TEG LY30 of less than 4% was associated with a 10-fold increased rate of pneumonia (19% vs. 1.5%; p = 0.002). In patients with traumatic brain injury, the same association was found (33% vs. 3.2%; p = 0.006). Adjusting for confounders, the tPA-TEG persisted as a substantial risk factor for pneumonia (adjusted odds ratio [OR], 35.7; 95% confidence interval [CI], 1.9-682; p = 0.018). Conclusions: Fibrinolysis resistance quantified by tPA-TEG within 48 hours of ICU admission is associated with an increased risk of pneumonia in patients in hemorrhagic shock and those at risk for VTE. Prospective validation of the tPA-TEG LY30 optimal cutoff for pneumonia and further investigation into whether endogenous FR is a cause of an altered immunity is warranted.

Plasma proteome analysis and validation of patients with community-acquired pneumonia: A cohort study

PURPOSE

This study aimed to investigate the diagnostic potential of plasma biomarkers of community-acquired pneumonia (CAP) and their severity grading.

EXPERIMENTAL DESIGN

Plasma proteomes from cohort I (n = 32) with CAP were analyzed by data-independent acquisition mass spectrometry (MS). MetaboAnalyst 5.0 was used to statistically evaluate significant differences in proteins from different samples, and demographic and clinical data were recorded for all enrolled patients. Cohort II (n = 80) was used to validate candidate biomarkers. Plasma protein levels were determined using quantitative enzyme-linked immunosorbent assay (ELISA). Correlations were assessed using Pearson's correlation coefficient. A receiver operating characteristic curve was used to verify the association between the variables, CAP diagnosis, and prognosis.

RESULTS

121 differentially expressed proteins (DEPs) were obtained between CAP and controls. These DEPs were mainly aggregated in pathways of phagosome(hsa04145) and complement and coagulation cascades (hsa04610). No significant differential proteins were detected in bacterial, viral, and mixed infection groups. The plasma levels of fetuin-A, alpha-1-antichymotrypsin (AACT), α1-acid glycoprotein (A1AG), and S100A8/S100A9 heterodimers detected by ELISA were consistent with those of MS. AACT, A1AG, S100A8/S100A9 heterodimer, and fetuin-A can potentially be used as diagnostic predictors, and fetuin-A and AACT are potential predictors of SCAP.

CONCLUSIONS AND CLINICAL RELEVANCE

Plasma protein profiling can successfully identify potential biomarkers for CAP diagnosis and disease severity assessment. These biomarkers should be further studied for their clinical application.

Diabetes Status, c-Reactive Protein, and Insulin Resistance in Community-Acquired Pneumonia-A Prospective Cohort Study

C-reactive protein (CRP) is commonly used to guide community-acquired pneumonia (CAP) treatment. A positive association between admission glucose and CRP levels has been observed in patients with CAP. The associations between prediabetes, unknown diabetes, acute-on-chronic hyperglycaemia, and CRP levels, and between admission CRP levels and insulin resistance (IR) in CAP, remain unexplored. This study investigated the associations firstly between chronic, acute, and acute-on-chronic hyperglycaemia and CRP levels, and secondly between admission CRP levels and IR in CAP. In a prospective cohort study of adults with CAP, the associations between chronic, acute, and acute-on-chronic hyperglycaemia (admission glucose minus HbA1c-derived average glucose) and CRP levels until admission day 3 were modelled with repeated-measures linear mixed models. IR was estimated with the homeostasis model assessment of IR (HOMA-IR). The association between admission CRP levels and HOMA-IR was modelled with linear regression. In 540 patients, no association between chronic, acute, or acute-on-chronic hyperglycaemia and CRP levels was found. In 266 patients, every 50 mg/L increase in admission CRP was associated with a 7% (95% CI 1-14%) higher HOMA-IR. In conclusion, our findings imply that hyperglycaemia does not influence CRP levels in patients with CAP, although admission CRP levels were positively associated with IR.

Diagnostic value of plasma heparin-binding protein and the heparin-binding protein-to-albumin ratio in patients with community-acquired Pneumonia: a retrospective study

BACKGROUND

Patients presenting to the emergency department with community-acquired pneumonia (CAP) are characterized by advanced age, comorbidities, critical illness and less-than-typical symptoms, posing a diagnostic challenge. Plasma heparin-binding protein (HBP) and the heparin-binding protein-to-albumin ratio (HBP/Alb) have not been adequately studied in the early diagnosis of CAP. This study assessed the diagnostic value of plasma HBP, HBP/Alb, and conventional inflammatory markers in emergency department patients with CAP.

METHODS

We enrolled 103 patients with CAP, retrospectively analyzed the patients' clinical data, and divided the CAP patients into antibiotic (n = 79) and non-antibiotic (n = 24) groups based on whether antibiotics were administered prior to blood sampling and laboratory tests. The control group was comprised of 52 non-infected patients admitted during the same period. Within 24 h of admission, plasma HBP, serum procalcitonin (PCT), white blood cell count (WBC), neutrophil-to-lymphocyte ratio (NLR) and HBP/Alb levels were collected separately and compared. The receiver operating characteristic (ROC) curve was plotted to assess the diagnostic value of each indicator for CAP patients. Utilizing the Kappa test, the consistency of each indicator used to evaluate CAP and clinical diagnosis was analyzed. Spearman correlation was used to analyze the correlation between plasma HBP and clinical indicators of CAP patients.

RESULTS

Plasma HBP, serum PCT, WBC, NLR and HBP/Alb were all elevated in the CAP group in comparison to the control group (P < 0.001). Plasma HBP, serum PCT, WBC, NLR and HBP/Alb levels did not differ statistically between antibiotic and non-antibiotic groups (P > 0.05). Plasma HBP and HBP/Alb had the highest diagnostic accuracy for CAP, the area under the ROC curve (AUC) were 0.931 and 0.938 (P < 0.0001), and the best cut-off values were 35.40 ng/mL and 0.87, respectively. In evaluating the consistency between CAP and clinical diagnosis, the Kappa values for HBP, PCT, WBC, NLR and HBP/Alb were 0.749, 0.465, 0.439, 0.566 and 0.773, respectively. Spearman correlation analysis showed that plasma HBP was positively correlated with serum PCT, WBC, NLR and HBP/Alb in CAP patients (P < 0.001).

CONCLUSIONS

Plasma HBP and HBP/Alb have a high clinical diagnostic value for CAP and can be used as good and reliable novel inflammatory markers in the emergency department for the early diagnosis of CAP patients.

Associations of Serum Clara Cell Protein 16 with Severity and Prognosis in Adults with Community-Acquired Pneumonia

Background

Clara cell protein 16 (CC16) has multiple functions, including antioxidant, anti-inflammatory, and immune regulation properties. Nevertheless, the concrete function of CC16 in adult patients with community-acquired pneumonia (CAP) remained blurred.

Methods

A total of 541 adult patients with CAP were recruited on admission. Peripheral blood specimens, clinical parameters, and demographic characteristics were collected. The concentration of serum CC16 was evaluated through ELISA. The relationships between serum CC16 and clinical parameters were appraised by Spearman or Pearson correlative analyses. The correlations of serum CC16 with severity and prognosis were assessed using linear or logistic regression models.

Results

The level of CC16 was gradually decreased across with the elevated severity scores system of CAP. After treatment, the level of serum CC16 was upregulated. Correlative analyses found that serum CC16 was negatively related to inflammatory cytokines. Additionally, multivariate linear and logistic regression models revealed that serum CC16 was inversely associated with severity scores system. In addition, reduced serum CC16 on admission elevated the risks of vasoactive agent usage, ICU admission, and death during hospitalization. We observed an almost discriminatory ability for severity and death between serum CC16 and severity scores system, and were all obviously elevated compared to routine inflammatory and infectious markers.

Conclusion

There are substantially inverse correlations between serum CC16 level on admission with severity scores and poorly prognostic outcomes, indicating that CC16 is involved in the pathophysiological process of CAP. This study is helpful for establishing the potential application of serum CC16 in risk evaluation and targeted treatment.

Erector spinae muscle-based nomogram for predicting in-hospital mortality among older patients with severe community-acquired pneumonia

BACKGROUND

No multivariable model incorporating erector spinae muscle (ESM) has been developed to predict clinical outcomes in older patients with severe community-acquired pneumonia (SCAP). This study aimed to construct a nomogram based on ESM to predict in-hospital mortality in patients with SCAP.

METHODS

Patients aged ≥ 65 years with SCAP were enrolled in this prospective observational study. Least absolute selection and shrinkage operator and multivariable logistic regression analyses were used to identify risk factors for in-hospital mortality. A nomogram prediction model was constructed. The predictive performance was evaluated using the concordance index (C-index), calibration curve, net reclassification improvement (NRI), integrated discrimination improvement (IDI), and decision curve analysis.

RESULTS

A total of 490 patients were included, and the in-hospital mortality rate was 36.1%. The nomogram included the following independent risk factors: mean arterial pressure, peripheral capillary oxygen saturation, Glasgow Coma Scale score (GCS), lactate, lactate dehydrogenase, blood urea nitrogen levels, and ESM cross-sectional area. Incorporating ESM into the base model with other risk factors significantly improved the C-index from 0.803 (95% confidence interval [CI], 0.761-0.845) to 0.836 (95% CI, 0.798-0.873), and these improvements were confirmed by category-free NRI and IDI. The ESM-based nomogram demonstrated a high level of discrimination, good calibration, and overall net benefits for predicting in-hospital mortality compared with the combination of confusion, urea, respiratory rate, blood pressure, and age ≥ 65 years (CURB-65), Pneumonia Severity Index (PSI), Acute Physiology and Chronic Health Evaluation II (APACHEII), and Sequential Organ Failure Assessment (SOFA).

CONCLUSIONS

The proposed ESM-based nomogram for predicting in-hospital mortality among older patients with SCAP may help physicians to promptly identify patients prone to adverse outcomes.

TRIAL REGISTRATION

This study was registered at www.chictr.org.cn (registration number Chi CTR-2300070377).

Microascus cirrosus SZ 2021: A potentially new genotype of Microascus cirrosus, which can cause fatal pulmonary infection in patients with acute leukemia following haplo‑HSCT

Uncommon Microascus cirrosus (M. cirrosus) species have been reported to cause an increasing number of subcutaneous and invasive fungal infections worldwide; since the first human infection was reported in 1992, seven cases have been reported in PubMed. The present study reports a novel genotype named M. cirrosus SZ 2021 isolated from a patient undergoing hematopoietic stem cell transplantation, who exhibited extensive drug resistance and suffered a fatal pulmonary infection. This isolated M. cirrosus was cultured and determined by morphological observation, multi-locus sequence typing, matrix-assisted laser desorption and ionization time-of-flight mass spectrometry, and whole genome sequencing by next-generation sequencing. The whole nucleotide sequence (32.61 Mb) has been uploaded in the NCBI database (PRJNA835605). In addition, M. cirrosus SZ 2021 was not sensitive to the commonly used antifungal drugs, including fluconazole, amphotericin B, 5-flucytosine and caspofungin. The current literature on human infections by M. cirrosus was reviewed to closely define the comprehensive clinical characteristics and etiological identification. In brief, the present study identified a new M. cirrosus and summarized the clinical characteristics of fungal pneumonia by M. cirrosus species. Complete laboratory identification methods from morphology to gene sequencing were also established for an improved etiological identification and further investigation into the real prevalence of invasive pneumonia by M. cirrosus.

Lung microbiome and origins of the respiratory diseases

The studies on the composition of the human microbiomes in healthy individuals, its variability in the course of inflammation, infection, antibiotic therapy, diets and different pathological conditions have revealed their intra and inter-kingdom relationships. The lung microbiome comprises of major species members of the phylum Bacteroidetes, Firmicutes, Actinobacteria, Fusobacteria and Proteobacteria, which are distributed in ecological niches along nasal cavity, nasopharynx, oropharynx, trachea and in the lungs. Commensal and pathogenic species are maintained in equilibrium as they have strong relationships. Bacterial overgrowth after dysbiosis and/or imbalanced of CD4⁺ helper T cells, CD8⁺ cytotoxic T cells and regulatory T cells (Treg) populations can promote lung inflammatory reactions and distress, and consequently acute and chronic respiratory diseases. This review is aimed to summarize the latest advances in resident lung microbiome and its participation in most common pulmonary infections and pneumonia, community-acquired pneumonia (CAP), ventilator-associated pneumonia (VAP), immunodeficiency associated pneumonia, SARS-CoV-2-associated pneumonia, acute respiratory distress syndrome (ARDS) and chronic obstructive pulmonary disease (COPD). We briefly describe physiological and immunological mechanisms that selectively create advantages or disadvantages for relative growth of pathogenic bacterial species in the respiratory tract. At the end, we propose some directions and analytical methods that may facilitate the identification of key genera and species of resident and transient microbes involved in the respiratory diseases' initiation and progression.

The Applicability of a 2-Transcript Signature to Identify Bacterial Infections in Children with Febrile Neutropenia

Febrile neutropenia is a common complication during chemotherapy in paediatric cancer care. In this setting, clinical features and current diagnostic tests do not reliably distinguish between bacterial and viral infections. Children with cancer (n = 63) presenting with fever and neutropenia were recruited for extensive microbiological and blood RNA sampling. RNA sequencing was successful in 43 cases of febrile neutropenia. These were classified as having probable bacterial infection (n = 17), probable viral infection (n = 13) and fever of unknown origin (n = 13) based on microbiological defined infections and CRP cut-off levels. RNA expression data with focus on the 2-transcript signature (FAM89A and IFI44L), earlier shown to identify bacterial infections with high specificity and sensitivity, was implemented as a disease risk score. The median disease risk score was higher in the probable bacterial infection group, -0.695 (max 2.795; min -5.478) compared to the probable viral infection group -3.327 (max 0.218; min -7.861), which in ROC analysis corresponded to a sensitivity of 0.88 and specificity of 0.54 with an AUC of 0.80. To further characterise the immune signature, analysis of significantly expressed genes and pathways was performed and upregulation of genes associated to antibacterial responses was present in the group classified as probable bacterial infection. Our results suggest that the 2-transcript signature may have a potential use as a diagnostic tool to identify bacterial infections in immunosuppressed children with febrile neutropenia.

Evaluation of Five Host Inflammatory Biomarkers in Early Diagnosis of Ventilator-Associated Pneumonia in Critically Ill Children: A Prospective Single Center Cohort Study

Background: Early diagnosis of ventilator-associated pneumonia (VAP) remains a challenge due to subjective clinical criteria and the low discriminative power of diagnostic tests. We assessed whether rapid molecular diagnostics in combination with Clinically Pulmonary Index Score (CPIS) scoring, microbiological surveillance and biomarker measurements of PTX-3, SP-D, s-TREM, PTX-3, IL-1β and IL-8 in the blood or lung could improve the accuracy of VAP diagnosis and follow-up in critically ill children. Methods: A prospective pragmatic study in a Pediatric Intensive Care Unit (PICU) was conducted on ventilated critically ill children divided into two groups: high and low suspicion of VAP according to modified Clinically Pulmonary Index Score (mCPIS). Blood and bronchial samples were collected on days 1, 3, 6 and 12 after event onset. Rapid diagnostics were used for pathogen identification and ELISA for PTX-3, SP-D, s-TREM, IL-1β and IL-8 measurements. Results: Among 20 enrolled patients, 12 had a high suspicion (mCPIS > 6), and 8 had a low suspicion of VAP (mCPIS < 6); 65% were male; and 35% had chronic disease. IL-1β levels at day 1 correlated significantly with the number of mechanical ventilation days (r_s = 0.67, p < 0.001) and the PICU stay (r = 0.66; p < 0.002). No significant differences were found in the levels of the other biomarkers between the two groups. Mortality was recorded in two patients with high VAP suspicion. Conclusions: PTX-3, SP-D, s-TREM, IL-1β and IL-8 biomarkers could not discriminate patients with a high or low suspicion of VAP diagnosis.

Efficacy of a paper-based interleukin-6 test strip combined with a spectrum-based optical reader for sequential monitoring and early recognition of respiratory failure in elderly pneumonia-a pilot study

Introduction: Community-acquired pneumonia (CAP) is lethal in elderly individuals who are more vulnerable to respiratory failure and require more emergency ventilation support than younger individuals. Interleukin-6 (IL-6) plays a crucial role and has predictive value in CAP; high serum IL-6 concentrations in adults are associated with high respiratory failure and mortality rates. Early detection of IL-6 concentrations can facilitate the timely stratification of patients at risk of acute respiratory failure. However, conventional enzyme-linked immunosorbent assay (ELISA) IL-6 measurement is laborious and time-consuming. Methods: The IL-6 rapid diagnostic system combined with a lateral flow immunoassay-based (LFA-based) IL-6 test strip and a spectrum-based optical reader is a novel tool developed for rapid and sequential bedside measurements of serum IL-6 concentrations. Here, we evaluated the correlation between the IL-6 rapid diagnostic system and the ELISA and the efficacy of the system in stratifying high-risk elderly patients with CAP. Thirty-six elderly patients (median age: 86.5 years; range: 65-97 years) with CAP were enrolled. CAP diagnosis was established based on the Infectious Diseases Society of America (IDSA) criteria. The severity of pneumonia was assessed using the CURB-65 score and Pneumonia Severity Index (PSI). IL-6 concentration was measured twice within 24 h of admission. Results: The primary endpoint variable was respiratory failure requiring invasive mechanical or non-invasive ventilation support after admission. IL-6 rapid diagnostic readouts correlated with ELISA results (p < 0.0001) for 30 samples. Patients were predominantly male and bedridden (69.4%). Ten patients (27.7%) experienced respiratory failure during admission, and five (13.9%) died of pneumonia. Respiratory failure was associated with a higher mortality rate (p = 0.015). Decreased serum IL-6 concentration within 24 h after admission indicated a lower risk of developing respiratory failure in the later admission course (Receiver Operating Characteristic [ROC] curve = 0.696). Conclusion: Sequential IL-6 measurements with the IL-6 rapid diagnostic system might be useful in early clinical risk assessment and severity stratification of elderly patients with pneumonia. This system is a potential point-of-care diagnostic device for sequential serum IL-6 measurements that can be applied in variable healthcare systems.

Antibiotic susceptibility pattern, risk factors, and prediction of carbapenem-resistant Pseudomonas aeruginosa in patients with nosocomial pneumonia

Objectives

This study was aimed at describing antibiotic susceptibility patterns and developing a predictive model by assessing risk factors for carbapenem-resistant Pseudomonas aeruginosa (CRPA).

Methods

A retrospective case-control study was conducted at a teaching hospital in China from May 2019 to July 2021. Patients were divided into the carbapenem-susceptible P. aeruginosa (CSPA) group and the CRPA group. Medical records were reviewed to find an antibiotic susceptibility pattern. Multivariate analysis results were used to identify risk factors and build a predictive model.

Results

A total of 61 among 292 patients with nosocomial pneumonia were infected with CRPA. In the CSPA and CRPA groups, amikacin was identified as the most effective antibiotic, with susceptibility of 89.7%. The CRPA group showed considerably higher rates of resistance to the tested antibiotics. Based on the results of mCIM and eCIM, 28 (45.9%) of 61 isolates might be carbapenemase producers. Independent risk factors related to CRPA nosocomial pneumonia were craniocerebral injury, pulmonary fungus infection, prior use of carbapenems, prior use of cefoperazone-sulbactam, and time at risk (≥15 d). In the predictive model, a score >1 point indicated the best predictive ability.

Conclusions

CRPA nosocomial pneumonia could be predicted by risk factor assessment particularly based on the underlying disease, antimicrobial exposure, and time at risk, which could help prevent nosocomial pneumonia.

[Relevant biomarkers in infectiology]

A biomarker in infectiology should ideally be able to identify infectious agents, monitor clinical response and determine the duration of treatment. This article answers the question to what extent C-reactive protein and procalcitonin meet these requirements and reports on the search for further biomarkers - e.g. with the help of "omics"-based technologies and the integration of artificial intelligence.

Analysis of cytokine levels, cytological findings, and MP-DNA level in bronchoalveolar lavage fluid of children with Mycoplasma pneumoniae pneumonia

BACKGROUND

The present study was conducted to determine the inflammatory response in the lungs of children with Mycoplasma pneumoniae pneumonia (MPP).

METHODS

This study retrospectively analyzed cytokine levels, cytological findings, and M. pneumoniae (MP)-DNA level in the bronchoalveolar lavage fluid (BALF) of 96 children with MPP. The study utilized Spearman's correlation method to evaluate the contribution of BALF and blood parameters in MPP children.

RESULTS

(1) A total of 96 MPP children were classified into the Low MP-DNA MPP group (BALF MP-DNA ≤ 105 copies/mL) and the High MP-DNA MPP group (BALF MP-DNA > 105 copies/mL); the Non-fever MPP group (no fever during the entire course of pneumonia) and the Fever MPP group; the Defervescence MPP group (fever had subsided at the time of bronchoscopy) and the Fervescence MPP group; and the Mild MPP group and the Severe MPP group. (2) The High MP-DNA MPP, Fever MPP, Fervescence MPP, and Severe MPP groups had higher levels of interleukin (IL)-6, IL-10, and tumor necrosis factor-α (TNF-α) in their BALF (all p < .05). (3) The proportions of neutrophils and macrophages in the BALF of the High MP-DNA MPP and Fever MPP groups increased and decreased, respectively (all p < .05). (4) In the BALF of MPP children, MP-DNA, IL-6, IL-10, TNF-α, and interferon gamma (IFN-γ) levels positively correlated with neutrophil proportion while negatively correlated with macrophage proportion (all p < .05). (5) The MP-DNA, IL-6, IL-10, TNF-α, and IFN-γ levels in the BALF of MPP children were positively correlated with the levels of C-reactive protein, procalcitonin, lactic dehydrogenase, fibrinogen, and d-dimer, while they were negatively correlated with the albumin level (all p < .05).

CONCLUSIONS

In children with MPP, the pulmonary inflammatory immune response was stronger in the High MP-DNA MPP, Fever MPP, Fervescence MPP, and Severe MPP groups. The relationship between pulmonary cytokine levels, MP-DNA load, and serum inflammatory parameters were found to be weak.

Multiplex sensing of IL-10 and CRP towards predicting critical illness in COVID-19 infections

Here we present a sensitive method for the detection and quantification of two (IL -10 and CRP) immuno-responsive biomarkers in various biofluids. The significance of these immune response biomarkers lies in them displaying elevated levels in critically ill COVID -19 patients. The developed electrochemical sensor contains a gold film electrode with ZnO nanoparticles deposited on its surface to increase the surface area of the working electrode while integrating antibody-antigen interactions into the detection system. This multiplex biosensor has a wide linear range from 0.01 μg/mL to 100 μg/mL and 0.1 pg/mL to 1000 pg/mL for CRP and IL10, respectively. The cross-reactivity of this multiplex sensor platform was evaluated between these two proteins and was <20%. Recovery studies were performed by spiking known concentrations in serum and urine samples. The recovery was calculated and ranged from 80% to 100%, confirming clinical applicability. This electrochemical sensing platform can aid in the early screening of COVID -19 patients to monitor for the development of more serious and potentially lethal symptoms.

Clinical Characteristics and Microbial Profiles of Paediatric Patients with Methicillin-Resistant Staphylococcus aureus Pneumonia in China

Background: Staphylococcus aureus can cause fatal pneumonia. The evolution of bacteria and the overuse of antibiotics have enhanced the drug resistance of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA). Objectives: This study aimed to recapitulate the microbiological profile and clinical characteristics of paediatric patients with MRSA. Methods: This retrospective study was conducted to investigate 1372 paediatric patients with S. aureus pneumonia from January 2017 to December 2021. Sputum specimens were collected and processed for performing bacterial culture and drug sensitivity tests. Medical records of patients were reviewed for clinical characteristics and laboratory examination results. Results: The MRSA and MSSA pneumonia mainly occurred in infants; however, comparisons of sex, age, and sampling time between patients with MRSA and MSSA pneumonia showed no significant differences (P > 0.05). The results of drug sensitivity in sputum culture revealed that all MRSA and MSSA isolates were susceptible to vancomycin, tigecycline, linezolid, teicoplanin, and ceftaroline. Methicillin-sensitive Staphylococcus aureus was completely sensitive to rifampicin and oxacillin. Methicillin-resistant Staphylococcus aureus was completely resistant to penicillin and oxacillin, while MSSA was less sensitive to penicillin. Methicillin-resistant Staphylococcus aureus and MSSA both maintained high sensitivity rates to gentamicin, sulfamethoxazole-trimethoprim, levofloxacin, and moxifloxacin, with the exception of clindamycin and erythromycin. According to our results, moreover, the sensitivity of MRSA to gentamicin and sulfamethoxazole-trimethoprim was significantly higher than that of MSSA (P < 0.05). The common symptoms of patients with S. aureus pneumonia were fever, cough, and wheezing. patients with MRSA pneumonia had significantly higher counts of white blood cells (WBCs), C-reactive protein (CRP), and procalcitonin (PCT) than patients with MSSA pneumonia (P < 0.05). Conclusions: The results of antimicrobial sensitivity test in sputum culture of MRSA and MSSA isolates can reflect the sensitivity of antibiotics and guide the use of clinical antibiotics. Infectious biomarkers can reflect the severity of infection and guide prognosis.

Diagnostic Potential of microRNAs in Extracellular Vesicles Derived from Bronchoalveolar Lavage Fluid for Pneumonia—A Preliminary Report

Current clinical needs require the development and use of rapid and effective diagnostic indicators to accelerate the identification of pneumonia and the process of microbiological diagnosis. MicroRNAs (miRNAs) in extracellular vesicles (EVs) have become attractive candidates for novel biomarkers to evaluate the presence and progress of many diseases. We assessed their performance as biomarkers of pneumonia. Patients were divided into the pneumonia group (with pneumonia) and the control group (without pneumonia). We identified and compared two upregulated miRNAs in EVs derived from bronchoalveolar lavage fluid (BALF-EVs) between the two groups (P_{miR–17–5p} = 0.009; P_{miR–193a–5p} = 0.031). Interestingly, in cell-debris pellets and EVs-free supernatants derived from bronchoalveolar lavage fluid (BALF-cell-debris pellets and BALF-EVs-free supernatants), total plasma, and EVs derived from plasma (plasma-EVs), the expression of miR–17–5p and miR–193a–5p showed no difference between pneumonia group and control group. In vitro experiments revealed that miR–17–5p and miR–193a–5p were strikingly upregulated in EVs derived from macrophages stimulated by lipopolysaccharide. MiR–17–5p (area under the curve, AUC: 0.753) and miR–193a–5p (AUC: 0.692) in BALF-EVs are not inferior to procalcitonin (AUC: 0.685) in the diagnosis of pneumonia. Furthermore, miR–17–5p and miR–193a–5p in BALF-EVs had a significantly higher specificity compared to procalcitonin and could be served as a potential diagnostic marker. MiR–17–5p and miR–193a–5p in EVs may be involved in lung inflammation by influencing the forkhead box O (FoxO) signaling pathway and protein processing in endoplasmic reticulum. This study is one of the few studies which focused on the potential diagnostic role of miRNAs in BALF-EVs for pneumonia and the possibility to use them as new biomarkers for a rapid and early diagnosis.

A prediction model for hospital mortality in patients with severe community-acquired pneumonia and chronic obstructive pulmonary disease

Background

No personalized prediction model or standardized algorithm exists to identify those at high risk of death among severe community-acquired pneumonia (SCAP) patients with chronic obstructive pulmonary disease (COPD). The aim of this study was to investigate the risk factors and to develop a useful nomogram for prediction of mortality in those patients.

Methods

We performed a retrospective, observational, cohort study in the intensive care unit (ICU) of West China Hospital, Sichuan University with all consecutive SCAP patients with COPD between December 2011 and December 2018. The clinical data within 24 h of admission to ICU were collected. The primary outcome was hospital mortality. We divided the patients into training and testing cohorts (70% versus 30%) randomly. In the training cohort, univariate and multivariate logistic regression analysis were used to identify independent risk factors applied to develop a nomogram. The prediction model was assessed in both training and testing cohorts.

Results

Finally, 873 SCAP patients with COPD were included, among which the hospital mortality was 41.4%. In training cohort, the independent risk factors for hospital mortality were increased age, diabetes, chronic renal diseases, decreased systolic blood pressure (SBP), and elevated fibrinogen, interleukin 6 (IL-6) and blood urea nitrogen (BUN). The C index was 0.840 (95% CI 0.809–0.872) in training cohort and 0.830 (95% CI 0.781–0.878) in testing cohort. Furthermore, the time-dependent AUC, calibration plots, DCA and clinical impact curves indicated the model had good predictive performance. Significant association of risk stratification based on nomogram with mortality was also found (P for trend < 0.001). The restricted cubic splines suggested that estimated associations between these predictors and hospital mortality were all linear relationships.

Conclusion

We developed a prediction model including seven risk factors for hospital mortality in patients with SCAP and COPD. It can be used for early risk stratification in clinical practice after more external validation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02181-9.

Unmet needs in pneumonia research: a comprehensive approach by the CAPNETZ study group

Introduction

Despite improvements in medical science and public health, mortality of community-acquired pneumonia (CAP) has barely changed throughout the last 15 years. The current SARS-CoV-2 pandemic has once again highlighted the central importance of acute respiratory infections to human health. The “network of excellence on Community Acquired Pneumonia” (CAPNETZ) hosts the most comprehensive CAP database worldwide including more than 12,000 patients. CAPNETZ connects physicians, microbiologists, virologists, epidemiologists, and computer scientists throughout Europe. Our aim was to summarize the current situation in CAP research and identify the most pressing unmet needs in CAP research.

Methods

To identify areas of future CAP research, CAPNETZ followed a multiple-step procedure. First, research members of CAPNETZ were individually asked to identify unmet needs. Second, the top 100 experts in the field of CAP research were asked for their insights about the unmet needs in CAP (Delphi approach). Third, internal and external experts discussed unmet needs in CAP at a scientific retreat.

Results

Eleven topics for future CAP research were identified: detection of causative pathogens, next generation sequencing for antimicrobial treatment guidance, imaging diagnostics, biomarkers, risk stratification, antiviral and antibiotic treatment, adjunctive therapy, vaccines and prevention, systemic and local immune response, comorbidities, and long-term cardio-vascular complications.

Conclusion

Pneumonia is a complex disease where the interplay between pathogens, immune system and comorbidities not only impose an immediate risk of mortality but also affect the patients’ risk of developing comorbidities as well as mortality for up to a decade after pneumonia has resolved. Our review of unmet needs in CAP research has shown that there are still major shortcomings in our knowledge of CAP.

Using procalcitonin testing to guide treatment decisions in care homes

Procalcitonin (PCT), a precursor of the hormone calcitonin, has emerged as a marker of bacterial infection that appears to be particularly useful in respiratory conditions. PCT testing has been shown to be beneficial in supporting healthcare professionals with their decision-making about treatment. It also has particular advantages in relation to the care of older people, notably in terms of assessment, recognising sepsis, reducing polypharmacy and informing antibiotic prescribing. This article discusses PCT testing in care homes and how its use can support nurses working in such settings to provide optimal care to residents. The article is underpinned by the latest evidence on PCT testing and the author's clinical experience as an advanced nurse practitioner working in a care home.

Prognostic value of proadrenomedullin in patients with COVID-19 pneumonia

Objective

The aim of the study was to assess the role of mid-regional proadrenomedullin (MR-proADM) in comparison with routine laboratory tests in patients with COVID-19.

Materials and methods

140 hospitalized patients aged 18 and older with COVID-19 pneumonia were included in prospective single-center study. Routine analyses were performed, and MR-proADM level was measured within the first and the third hospital days using Human MR pro-ADM (Mid-regional pro-adrenomedullin) ELISA Kit with a sensitivity of 0.469 pmol/L (immunofluorescence assay). National Early Warning Score (NEWS) was used for primary assessment of the disease severity. According to disease outcome the patients were divided into two groups: discharged patients (n = 110, 78.6%) and deceased patients (n = 30, 21.4%). Results: The groups had no statistically significant difference in sex, comorbidity, body temperature, oxygen saturation level, heart rate, respiratory rate, and C-reactive protein (CRP) level and procalcitonin (PCT). The deceased patients had statistically significant difference in age (median, 76 years; interquartile range, 73.2–78.2 vs. median, 66 years; interquartile range, 62–67; p < 0.0001), NEWS value (median, 5; interquartile range, 3–8 vs. median, 2; interquartile range, 0–6; p <0.05), hospitalization period (median, 17; interquartile range, 7–35 vs. median, 6; interquartile range, 3–14), quantitative CT extent of lung damage > 50% [n = 26 (86.7%) vs. n = 9 (8.2%) p < 0.0001], level of leukocytes (median, 11.4 ×109/L; interquartile range, 6.2–15.5 vs. median, 5.3 ×109/L; interquartile range, 4.7–6.4; p = 0.003), level of neutrophils (median, 80.9%; interquartile range, 73.6–88.6 vs. median, 72.6%; interquartile range, 68.7–76.9; p = 0.027), level of MR-proADM at the first hospital day (median, 828.6 pmol/L; interquartile range, 586.4–1,184.6 vs. median, 492.6 pmol/L; interquartile range, 352.9–712.2; p = 0.02), and level of MR-proADM at the third hospital day (median, 1,855.2 pmol/L; interquartile range, 1,078.4–2,596.5 vs. median, 270.7 pmol/L; interquartile range, 155.06–427.1).

Conclusion

Mid-regional proadrenomedullin has a higher prognostic value in patients with COVID-19 in comparison with routine inflammatory markers (leukocyte and neutrophils levels, CRP, and PCT) and NEWS.

A retrospective observational study of biomarker levels and severity assessment in pediatric community-acquired pneumonia

METHODS

A retrospective chart review was conducted on children (aged 60 days to 18 years) diagnosed with CAP, and admitted to a regional, tertiary hospital (Charleston, WV, USA) for 3 years (2015-2018). Patients were stratified into 2 severity cohorts, mild (no ICU care), and moderate/severe (required ICU care). Biomarker values were then compared between the severity cohorts and area under the curve (AUC), and cut-off values and performance characteristics were calculated.

RESULTS

A total of 108 patients met inclusion criteria with 46% having moderate/severe CAP. Elevated levels of CRP (51.7 mg/L in mild vs. 104.8 mg/L in moderate/severe, P = .003, PCT (0.29 ng/ml in mild vs. 4.02 ng/mL in moderate/severe, P = .001) and band counts (8% in mild vs. 15% moderate/severe, P = .009) were associated with increased pneumonia severity. In predicting moderate/severe CAP, PCT had the highest AUC of 0.77 (P = .001) followed by bands AUC of 0.69 (P = .009) and CRP AUC of 0.67 (P = .003). Cut-off for PCT of 0.55 ng/mL had a sensitivity of 83% and a specificity of 65%. Cut-off level of 53.1 mg/L for CRP had a sensitivity of 79% and specificity of 52%. Cut off level of 12.5% bands had a sensitivity of 61% and specificity of 71%. In a multivariable model controlled for patient demographics and other biomarker levels, only PCT levels significantly predicted moderate/severe CAP (adjusted odds ratio: 1.40 [95% CI, 1.14-1.73], P = .002).

CONCLUSION

Biomarkers, in particular PCT, obtained early in hospitalization may perform as possible predictors for CAP severity in children and be beneficial in guiding CAP management. However, biomarkers in pneumonia should not drive severity assessment or patient management independent of clinical presentation.

Evaluation of the significance of interleukin-6 in the diagnosis of postoperative pneumonia: a prospective study

Background

Postoperative pneumonia (PP) is one of the most common complications after cardiac surgery. This study was designed to access the diagnostic value of interleukin-6 (IL-6) for pneumonia within the first 5 days after cardiac surgery in adults.

Method

This prospective observational study enrolled 694 patients who admitted to our center from 10 October 2020 to 30 June 2021. Blood samples were collected after admission and on five consecutive days after surgery to measure IL-6, procalcitonin (PCT), C-reactive protein (CRP) and white blood cells (WBC) respectively. Combined with clinical data, we assessed the diagnostic performance of different biomarkers using univariate and multifactorial analyses as well as receiver operating characteristic curves (ROC) and the area under the curve (AUC).

Result

Finally, 68 patients were diagnosed with PP (PP Group). In addition, 626 cases were assigned to the control group (Non-PP Group). From postoperative day 1 (POD1) to day 5, IL-6 and PCT levels showed higher diagnostic value (P < 0.001, P < 0.05, respectively); meanwhile, there was no difference in white blood cell counts between the two groups; CRP showed some value from POD2 onwards (P < 0.001). Among these biomarkers, IL-6 on POD1 [AUC: 0.78, 95% confidence interval (CI): 0.71–0.83], IL-6 on POD2 (AUC: 0.77, 95% CI: 0.71–0.82) and CRP levels on POD3 (AUC: 0.77, 95% CI: 0.70–0.84) had the highest diagnostic value. Multivariate analysis found that smoking status [odds ratio(OR): 7.79, 95% CI: 3.05, 19.88, p < 0.001], drinking status (OR: 22.68, 95% CI: 9.29, 55.37, p < 0.001) and hypertension (OR: 2.85, 95% CI: 1.28, 6.35, p = 0.011), IL-6 on POD2 (OR: 1.01, 95% CI: 1.00, 1.01, p = 0.018), mechanical ventilation time (OR: 1.03, 95% CI: 1.00, 1.05, p = 0.040) and intensive care unit stay time (OR: 1.01, 95% CI: 1.00, 1.02, p < 0.001) were independent risk factors for postoperative pneumonia.

Conclusion

Smoking, drinking, hypertension, prolonged duration of mechanical ventilation and intensive care unit stay, and IL-6 on POD2 were independent risk factors for pneumonia after cardiovascular surgery. IL-6 level on POD2 may serve as a promising indicator, better than WBC, PCT and CRP.

Advances in diagnostic tools for respiratory tract infections. From tuberculosis to COVID19: changing paradigms?

Respiratory tract infections (RTI) are one of the commonest reasons for seeking healthcare, but are amongst the most challenging diseases in terms of clinical decision making. Proper and timely diagnosis is critical in order to optimize management and prevent further emergence of antimicrobial resistance by misuse, or overuse of antibiotics. Diagnostic tools for RTI include those involving syndromic and etiological diagnosis: from clinical and radiological features to laboratory methods targeting both pathogen detection and host biomarkers, as well as their combinations in terms of clinical algorithms. They also include tools for predicting severity and monitoring treatment response. Unprecedented milestones have been achieved in the context of the COVID-19 pandemic, involving the most recent applications of diagnostic technologies both at genotypic and phenotypic level, which have changed paradigms in infectious respiratory diseases in terms of why, how and where diagnostics are performed. The aim of this review is to discuss advances in diagnostic tools that impact clinical decision making, surveillance and follow-up of RTI and tuberculosis. If properly harnessed, recent advances in diagnostic technologies, including omics and digital transformation emerge as an unprecedented opportunity to tackle ongoing and future epidemics while handling antimicrobial resistance from a One Health perspective.

Metabolic profile of exhaled breath condensate from the pneumonia patients

PURPOSE OF THE STUDY

Exhaled breath condensate (EBC) is increasingly being used for disease diagnosis and environmental exposure assessment as a noninvasive method reducing the risk of exposure. The purpose of this study was to investigate the application of a new sample type of EBC in pneumonia by metabolomics and to explore differential metabolites and potential metabolic pathways.

MATERIALS AND METHODS

A case-control study was performed at the Peking University Third Hospital from August to December 2020. C-MS/MS analyses were performed on EBC samples using a UHPLC system.

RESULTS

Totally 22 patients with pneumonia and 24 healthy controls were recruited. Using untargeted metabolomics based on LC-MS/MS analysis, 25 kinds of differential metabolites were found. Through a comprehensive analysis of the pathways in which the differential metabolites were located, the key pathway with the highest correlation with the difference of metabolites was taurine and hypotaurine metabolism.

CONCLUSIONS

The study implicates that the hypotaurine/taurine metabolic pathway may play a role on the development of pneumonia through metabolism analysis on EBC and the 3-Sulfinoalanine may be used as a biomarker in the diagnosis of pneumonia.

Melioidosis presenting predominantly as thoracic empyema

Burkholderia pseudomallei has been rarely mentioned as a causative organism of thoracic empyema in previous literature. Here, we reported two cases (a 66-year-old male farmer and a 57-year-old male security guard) presenting with fever and pleuritic chest pain. Their chest computed tomography scans revealed pleural effusion which was frank pus confirmed through thoracentesis. The result of pus culture isolated B. pseudomallei suitable to diagnose melioidosis. These patients were treated successfully with appropriate antibiotics without chest tube drainage. Although uncommon, melioidosis could present exclusively as thoracic empyema.

Potential Value of Presepsin Guidance in Shortening Antibiotic Therapy in Septic Patients: a Multicenter, Prospective Cohort Trial

INTRODUCTION

Long-term use of antibiotics for septic patients leads to bacterial resistance, increased mortality, and hospital stay. In this study, we investigated an emerging biomarker presepsin-guided strategy, which can be used to evaluate the shortening of antibiotic treatment in patients with sepsis without risking a worse outcome.

METHODS

In this multicenter prospective cohort trial, patients were assigned to the presepsin or control groups. In the presepsin group, antibiotics were ceased based on predefined cut-off ranges of presepsin concentrations. The control group stopped antibiotics according to international guidelines. The primary endpoints were the number of days without antibiotics within 28 days and mortality at 28 and 90 days. Secondary endpoints were the percentage of patients with a recurrent infection, length of stay in ICU and hospital, hospitalization costs, days of first episode of antibiotic treatment, percentage of antibiotic administration and multidrug-resistant bacteria, and SOFA score.

RESULTS

Overall, 656 out of an initial 708 patients were eligible and assigned to the presepsin group (n = 327) or the control group (n = 329). Patients in the presepsin group had significantly more days without antibiotics than those in the control group (14.54 days [SD 9.01] vs. 11.01 days [SD 7.73]; P < 0.001). Mortality in the presepsin group showed no difference to that in the control group at days 28 (17.7% vs. 18.2%; P = 0.868) and 90 (19.9% vs. 19.5%; P = 0.891). Patients in the presepsin group had a significantly shorter mean length of stay in the hospital and lower hospitalization costs than control subjects. There were no differences in the rate of recurrent infection and multidrug-resistant bacteria and the SOFA score tendency between the two groups.

CONCLUSIONS

Presepsin guidance has potential to shorten the duration of antibiotic treatment in patients with sepsis without risking worse outcomes of death, recurrent infection, and aggravation of organ failure.

TRIAL REGISTRATION

ChiCTR, ChiCTR1900024391. Registered 9 July 2019-Retrospectively registered, http://www.chictr.org.cn.

Skeletal muscle depletion predicts death in severe community-acquired pneumonia patients entering ICU

BACKGROUND

Sarcopenia, or skeletal muscle depletion, was common in the elderly and often led to a poor prognosis of diseases. The area of the psoas muscle in abdominal computed tomography (CT) is the most common used for diagnosing sarcopenia. However, patients with pneumonia routinely only undergo chest CT.

OBJECTIVES

This study aimed to determine whether paraspinal muscle area (PMA) obtained by chest CT can predict death for community-acquired pneumonia (SCAP) patients entering intensive care unit (ICU).

METHODS

This study enrolled 208 SCAP patients admitted to ICU after undergoing chest CT. PMA, paraspinal muscle radiodensity (PMD), and lean paraspinal muscle area (LPMA) were calculated on chest CT images. The main outcome was mortality during hospitalization. Logistic regression, receiver operating characteristic (ROC) curve, and Kaplan-Meier curves were used to evaluate forecasting effectiveness.

RESULTS

The primary outcome occurred in 76 (36.53%) patients. In multivariate logistic regression, PMA, lactic dehydrogenase (LDH), invasive mechanical ventilation (IMV), red blood cell (RBC) and age≥ 65 years were independent risk factors predicting death during hospitalization (adjusted Odds Ratio [OR]: 0.886, 1.002, 3.178, 0.612 and 2.003, respectively). The area under curve (AUC) of PMA to predict death was 0.720 (P< 0.001). During hospitalization, the median survival time of high-PMA (51.00 days) and low-PMA groups (20.00 days) was statistically significant (P< 0.001).

CONCLUSION

Lower PMA was associated with an increased risk of death for SCAP patients admitted to the ICU. In other words, PMA may help early identify adverse prognosis of SCAP patients admitted to ICU.

Metabolomics study of Angelica sinensis (Oliv.) Diels on the abnormal uterine bleeding rats by ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry analysis

The objective of this study was to explore the effects and underlying intervention mechanisms of Angelica water extract (AWE) on abnormal uterine bleeding (AUB) based on serum metabolomics. Firstly, the concentration of main active substances in AWE was determined and the chemical components were identified by UPLC-Q-Exactive Orbitrap-MS/MS. A drug-induced abortion model was established by mifepristone and misoprostol. After administration AWE (2.16 g/kg) for 7 days, the coagulation function, serum hormone levels, H&E staining, and immunohistochemistry observation of uterus were detected. In addition, serum metabolites profiles were performed on ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS). The contents of ferulic acid, senkyunolide A, and ligustilide in AWE were 0.7276, 0.0868, and 1.9908 mg/g, respectively. Twenty-six compounds were identified in AWE. It was found that AWE was effective in regulation of coagulation function and promoting endometrial recovery. Meanwhile, the levels of E2, Pg, and HCG and the expression of ERα, Erβ, and PR were down-regulated in AUB model and up-regulated by the treatment of AWE. Twenty-one potential biomarkers were eventually identified by multivariate statistical analysis. Study indicated that glycerophospholipid, sphingolipid, amino acids, retinol metabolism and primary bile acid biosynthesis were the main related metabolic pathways involved for the treatment of AUB by AWE. The results showed that AWE has potential therapeutic effect on AUB by altering the metabolic aberrations.

Arginine vasopressin and pathophysiology of COVID-19: An innovative perspective

In Covid-19, systemic disturbances may progress due to development of cytokine storm and dysregulation of and plasma osmolarility due to high release of pro-inflammatory cytokines and neuro-hormonal disorders. Arginine vasopressin (AVP) which is involve in the regulation of body osmotic system, body water content, blood pressure and plasma volume, that are highly disturbed in Covid-19 and linked with poor clinical outcomes. Therefore, this present study aimed to find the potential association between AVP serum level and inflammatory disorders in Covid-19. It has been observed by different recent studies that physiological response due to fever, pain, hypovolemia, dehydration, and psychological stress is characterized by activation release of AVP to counter-balance high blood viscosity in Covid-19 patients. In addition, activated immune cells mainly T and B lymphocytes and released pro-inflammatory cytokines stimulate discharge of stored AVP from immune cells, which in a vicious cycle trigger release of pro-inflammatory cytokines. Vasopressin receptor antagonists have antiviral and anti-inflammatory effects that may inhibit AVP-induced hyponatremia and release of pro-inflammatory cytokines in Covid-19. In conclusion, release of AVP from hypothalamus is augmented in Covid-19 due to stress, high pro-inflammatory cytokines, high circulating AngII and inhibition of GABAergic neurons. In turn, high AVP level leads to induction of hyponatremia, inflammatory disorders, and development of complications in Covid-19 by activation of NF-κB and NLRP3 inflammasome with release of pro-inflammatory cytokines. Therefore, AVP antagonists might be novel potential therapeutic modality in treating Covid-19 through mitigation of AVP-mediated inflammatory disorders and hyponatremia.

Systematic Review and Meta-Analysis of Diagnostic Biomarkers for Pediatric Pneumonia

BACKGROUND

Pneumonia causes significant morbidity and mortality in children worldwide, especially in resource-poor settings. Accurate identification of bacterial etiology leads to timely antibiotic initiation, minimizing overuse, and development of resistance. Host biomarkers may improve diagnostic sensitivity and specificity. We assessed the ability of biomarkers to correctly identify bacterial pneumonia in children who present with respiratory distress.

METHODS

A librarian-directed search was conducted of MEDLINE, EMBASE, CENTRAL, Global Health, the World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov to May 2020 with no language restriction. Included studies compared a diagnostic biomarker in children with bacterial pneumonia to those with nonbacterial respiratory distress.

RESULTS

There were 31 observational studies of 23 different biomarkers. C-reactive protein (CRP), procalcitonin (PCT), white blood cell (WBC) count, and erythrocyte sedimentation rate (ESR) were the biomarkers with sufficient data for meta-analysis. Meta-analysis revealed that CRP and PCT best differentiated bacterial from viral pneumonia with CRP summary AUROC (area under the receiver operating characteristic curve) 0.71 (0.69-0.73), Youden index 53 mg/L, sensitivity 0.70 (0.68-0.78), and specificity 0.64 (0.58-0.68) and PCT summary AUROC 0.70 (0.67-0.74), Youden index 0.59 ng/mL, sensitivity 0.69 (0.65-0.77), and specificity 0.64 (0.60-0.68). WBC and ESR did not perform as well. Nineteen other inflammatory and immunologic biomarkers were identified including CRP/mean platelet value, neutrophil/leukocyte ratio, interleukin 6, and interferon-alpha, with sensitivities from 60% to 85% and specificities from 76% to 83%.

CONCLUSION

CRP and PCT performed better than WBC and ESR but had suboptimal sensitivity. Some less well-studied novel biomarkers appear to have promise particularly in combination.

Capacity and use of diagnostics and treatment for patients with severe acute respiratory infections in the pre-COVID-19 era in district and provincial hospitals in Viet Nam

Objective

To describe the burden of severe acute respiratory infection (SARI) and the infrastructure and current practices of SARI management in hospitals in Viet Nam.

Methods

We conducted a short observational study at critical care units (CCUs) in 32 district hospitals and 16 provincial hospitals in five provinces in Viet Nam from March to July 2019. We collected data on hospital equipment and medicines used in SARI management. At the patient level, data were collected for 14 consecutive days on all patients presenting to CCUs, including information on demographics, intervention and treatment within 24 hours of CCU admission and 7-day outcome.

Results

There were significant differences between district and provincial hospitals in the availability of microbial culture, rapid influenza diagnostic tests, inflammatory markers and mechanical ventilation. Among 1722 eligible patients admitted to CCUs, there were 395 (22.9%) patients with SARI. The median age of SARI patients was 74 (interquartile range: 58–84) years; 49.1% were male. Although systemic antibiotics were available in all hospitals and were empirically given to 93.4% of patients, oseltamivir was available in 25% of hospitals, and only 0.5% of patients received empiric oseltamivir within 24 hours of admission. The 7-day mortality was 6.6% (26/395). Independent factors associated with 7-day mortality were septic shock and requiring respiratory support within 24 hours of admission.

Discussion

SARI is a major burden on CCUs in Viet Nam. Barriers to delivering quality care include the limited availability of diagnostics and medication and non-protocolized management of SARI in CCUs.

Prognostic values of procalcitonin and platelet in the patient with urosepsis

BACKGROUND

The patient suffering from urinary sepsis is often accompanied by elevated serum procalcitonin (PCT) levels and a decline in the average platelet count (PLT), which could result in a poor prognosis. This study aimed to evaluate the value of PCT and PLT in determining the severity of urinary sepsis.

METHODS

A total of 120 urosepsis patients enrolled were divided into a survival group and a death group, respectively, according to their status within 14 days after admission. Changes in PCT and PLT levels between the 2 groups were compared at different time points. A receiver operating characteristic (ROC) curve was eventually obtained to predict the prognostic value of PCT and PLT.

RESULTS

The PCT levels in the survival group declined gradually after admission, and the PLT decreased at first but increased rapidly in subsequence. The PCT level in the death group, however, declined in a flat-slope trend or was hardly noticeable together with the number of PLT reduced significantly. In particular, it is on the 3rd day that PCT tended to positively correlate with acute physiological and chronic health score II (APACHE II) score (r = 0.730, P < .05), but negatively with PLT (r = 0.472, P < .05). The APACHE II score and PLT (r = 0.612, P < .05) were also negatively correlated with each other. As indicated by the ROC curve, the PCT level on the 3rd day after admission was of great value for the clinical mortality prognosis, and the area under the curve was 0.858. Moreover, PLT also has a high predictive value for prognosis. Area under the curve is 0.951. When the PLT was more than 51 × 109 /L, the sensitivity was up to 90%, and the specificity was 90%.

CONCLUSION

PLT and PCT levels are closely related to the APACHE II score, which could indicate the severity of urosepsis in patients. The contribution of this study was to confirm that dynamic monitoring of the changes in PCT and PLT helps determine the prognosis of urosepsis patients.

Comparative Characterization and Risk Stratification of Asymptomatic and Presymptomatic Patients With COVID-19

The identification of asymptomatic, non-severe presymptomatic, and severe presymptomatic coronavirus disease 2019 (COVID-19) in patients may help optimize risk-stratified clinical management and improve prognosis. This single-center case series from Wuhan Huoshenshan Hospital, China, included 2,980 patients with COVID-19 who were hospitalized between February 4, 2020 and April 10, 2020. Patients were diagnosed as asymptomatic (n = 39), presymptomatic (n = 34), and symptomatic (n = 2,907) upon admission. This study provided an overview of asymptomatic, presymptomatic, and symptomatic COVID-19 patients, including detection, demographics, clinical characteristics, and outcomes. Upon admission, there was no significant difference in clinical symptoms and CT image between asymptomatic and presymptomatic patients for diagnosis reference. The mean area under the receiver operating characteristic curve (AUC) of the differential diagnosis model to discriminate presymptomatic patients from asymptomatic patients was 0.89 (95% CI, 0.81-0.98). Importantly, the severe and non-severe presymptomatic patients can be further stratified (AUC = 0.82). In conclusion, the two-step risk-stratification model based on 10 laboratory indicators can distinguish among asymptomatic, severe presymptomatic, and non-severe presymptomatic COVID-19 patients on admission. Moreover, single-cell data analyses revealed that the CD8+T cell exhaustion correlated to the progression of COVID-19.

Calprotectin: An Ignored Biomarker of Neutrophilia in Pediatric Respiratory Diseases

Calprotectin (CP) is a non-covalent heterodimer formed by the subunits S100A8 (A8) and S100A9 (A9). When neutrophils become activated, undergo disruption, or die, this abundant cytosolic neutrophil protein is released. By fervently chelating trace metal ions that are essential for bacterial development, CP plays an important role in human innate immunity. It also serves as an alarmin by controlling the inflammatory response after it is released. Extracellular concentrations of CP increase in response to infection and inflammation, and are used as a biomarker of neutrophil activation in a variety of inflammatory diseases. Although it has been almost 40 years since CP was discovered, its use in daily pediatric practice is still limited. Current evidence suggests that CP could be used as a biomarker in a variety of pediatric respiratory diseases, and could become a valuable key factor in promoting diagnostic and therapeutic capacity. The aim of this study is to re-introduce CP to the medical community and to emphasize its potential role with the hope of integrating it as a useful adjunct, in the practice of pediatric respiratory medicine.

Copeptin, pro-atrial natriuretic peptide and pro-adrenomedullin as markers of hypoxic stress in patients with obstructive sleep apnea-a prospective intervention study

Study Objectives

Obstructive sleep apnea (OSA) might lead to oxidative stress, inflammation and elevated circulating copeptin, proANP and proADM levels. We aimed to evaluate whether the levels of these prohormones are higher in patients with OSA and whether they might change under continuous positive airway pressure (CPAP) therapy, serving as potential proxies for the diagnosis and therapy-response in OSA.

Methods

A total of 310 patients with suspicion of OSA were recruited. Screening for OSA was performed using overnight pulse oximetry followed by polygraphy and a venous puncture in the morning. All patients diagnosed with OSA underwent CPAP adaptation. A venous puncture was conducted in the night before CPAP and in the following morning. At 1 and 6 months of treatment, polygraphy was performed, followed by a venous puncture in the morning. In the acquired blood, copeptin, proANP and proADM levels were measured.

Results

We analyzed 232 patients with OSA and 30 patients without OSA. Our results indicated that only copeptin levels differed significantly among patients with and without OSA at baseline. In OSA patients, the levels of proADM significantly changed after 1 and 6 months on CPAP therapy, when compared to baseline (p < 0.001 and p = 0.020). Additionally, proANP levels significantly decreased after 12 h on CPAP therapy, as compared to baseline levels (p < 0.001).

Conclusions

Copeptin is significantly associated with the presence of OSA. ProANP levels might serve as a potential proxy for the acute response to non-invasive ventilation (12 h), while proADM reflects the long-term response (1 and 6 months).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-021-01704-0.

Prognostic Value of Procalcitonin and C-Reactive Protein in 1608 Critically Ill Patients with Severe Influenza Pneumonia

Background: Procalcitonin (PCT) and C-Reactive protein (CRP) are well-established sepsis biomarkers. The association of baseline PCT levels and mortality in pneumonia remains unclear, and we still do not know whether biomarkers levels could be related to the causative microorganism (GPC, GNB). The objective of this study is to address these issues. Methods: a retrospective observational cohort study was conducted in 184 Spanish ICUs (2009–2018). Results: 1608 patients with severe influenza pneumonia with PCT and CRP available levels on admission were included, 1186 with primary viral pneumonia (PVP) and 422 with bacterial Co-infection (BC). Those with BC presented higher PCT levels (4.25 [0.6–19.5] versus 0.6 [0.2–2.3]ng/mL) and CRP (36.7 [20.23–118] versus 28.05 [13.3–109]mg/dL) as compared to PVP (p < 0.001). Deceased patients had higher PCT (ng/mL) when compared with survivors, in PVP (0.82 [0.3–2.8]) versus 0.53 [0.19–2.1], p = 0.001) and BC (6.9 [0.93–28.5] versus 3.8 [0.5–17.37], p = 0.039). However, no significant association with mortality was observed in the multivariate analysis. The PCT levels (ng/mL) were significantly higher in polymicrobial infection (8.4) and GPC (6.9) when compared with GNB (1.2) and Aspergillus (1.7). The AUC-ROC of PCT for GPC was 0.67 and 0.32 for GNB. The AUROC of CRP was 0.56 for GPC and 0.39 for GNB. Conclusions: a single PCT/CRP value at ICU admission was not associated with mortality in severe influenza pneumonia. None of the biomarkers have enough discriminatory power to be used for predicting the causative microorganism of the co-infection.

Treatment of infections in cancer patients: an update from the neutropenia, infection and myelosuppression study group of the Multinational Association for Supportive Care in Cancer (MASCC)

INTRODUCTION

Patients with hematological and advanced solid malignancies have acquired immune dysfunction, often exacerbated by treatment, posing a significant risk for the development of infections. This review evaluates the utility of current clinical and treatment guidelines, in the setting of management of infections in cancer patients.

AREAS COVERED

These include causes of infection in cancer patients, management of patients with high-risk and low-risk febrile neutropenia, management of low-risk patients in an outpatient setting, the role of granulocyte colony-stimulating factor (G-CSF) in the prevention and treatment of neutropenia-related infections, management of lung infections in various clinical settings, and emerging challenges surrounding the risk of infection in cancer patients treated with novel treatments. The literature search was performed by accessing PubMed and other databases, focusing on published clinical trials of relevant anti-cancer agents and diseases, primarily covering the recent past, but also including several key studies published during the last decade and, somewhat earlier in a few cases.

EXPERT REVIEW

Notwithstanding the promise of gene therapy/gene editing in hematological malignancies and some types of solid cancers, innovations introduced in clinical practice include more discerning clinical management such as the generalized use of biosimilar formulations of G-CSF and the implementation of novel, innovative immunotherapies.

Dynamic Immune/Inflammation Precision Medicine: The Good and the Bad Inflammation in Infection and Cancer

Normal or “good” inflammation process starts from a local cellular response against injury or any infectious agent, with the activation of neutrophils, macrophages, Langerhans cells, dendritic cells, and innate immune cells. Cytokines and chemokines are produced to amplify the local inflammatory process followed by the migration of immune cells to the regional lymph nodes where adaptive immune response is initiated. Systemic inflammation enhances the biological response to mobilize additional cells from central and peripheral immune/hematopoietic system. Local mechanisms to limit inflammation are initiated and lead to healing. During the normal inflammatory process, there is a balance between the production of inflammatory chemokines/cytokines such as Tumor Necrosis Factor (TNF)-α, interleukin (IL)-6 and IL-1 and the production of compounds that limit inflammation and have an immune suppressive effect, such as IL-10 and Transforming Factor (TGF) β. IL-6 and IL-6/soluble IL-6 Receptor (R) complex stimulate liver cells to produce inflammatory proteins, which represents the systemic inflammation response. The magnitude and the duration of the systemic inflammatory response are linked to the cause, under genetic and epigenetic control. Significant inflammation as seen in septic shock, in severe forms of infections or in certain active cancers, represents the “bad inflammation”, correlated with a poor prognosis. In addition, the persistence of a chronic smoldering inflammation may lead to pathological situations which are observed in the majority of inflammatory, degenerative, dysmetabolic, or dysimmune diseases and cancer. Chronic smoldering inflammation is a cross between different pathological situations possibly linked. In addition, within the tumor microenvironment, inflammatory process results from different cellular mechanisms modulated by metabolic and vascular changes. On the contrary, a limited and balanced inflammation initiates the normal immune response, including the adaptive response which amplifies any immunotherapy, including vaccines. Immune checkpoint inhibitors and chimeric antigen receptor (CAR) T-cells are associated with cytokine release syndrome, a clinical risk leading to the use of anti-cytokine drugs. Nowadays, it is time to monitor the dynamic inflammatory process for a better immune precision medicine in both infections and cancer.

Bronchoalveolar Lavage and Blood Markers of Infection in Critically Ill Patients-A Single Center Registry Study

Microbiological sampling is an indispensable targeted antibiotic therapy for critically ill patients. Invasive respiratory sampling by bronchoalveolar lavage (BAL) can be performed to obtain samples from the lower respiratory tract. It is debated as to whether blood markers of infection can predict the outcome of BAL in a medical intensive care unit (ICU). Retrospectively, all ICU patients undergoing BAL from 2009-2018 were included. A total of 468 BAL samples from 276 patients (average age 60 years, SAPS2 47, ICU-mortality 41.7%) were analyzed. At the time of BAL, 94.4% patients were mechanically ventilated, 92.9% had suspected pneumonia, 96.2% were on antibiotic therapy and 36.3% were immunocompromised. Relevant bacteria were cultured in 114/468 (24.4%) cases of BAL. Patients with relevant bacteria in the culture had a higher ICU mortality rate (45.6 vs. 40.4%, p = 0.33) and were significantly less likely to be on a steroid (36 vs. 52%, p < 0.01) or antimycotic (14.9 vs. 34.2%, p < 0.01), while procalcitonin (PCT), C-reactive protein (CRP), and white blood cell (WBC) counts were similar. The area under the receiver operating curve (AUC) values for positive culture and PCT, CRP and WBC counts were low (0.53, 0.54 and 0.51, respectively). In immunocompromised patients, AUC values were higher (0.65, 0.57 and 0.61, respectively). Therefore, microbiological cultures by BAL revealed relevant bacteria in 24.4% of samples. Our data, therefore, might suggest that indication for BAL should not be based on blood markers of infection.

When Does the Cytokine Storm Begin in COVID-19 Patients? A Quick Score to Recognize It

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus that is responsible for coronavirus disease 2019 (COVID-19), which has rapidly spread across the world, becoming a pandemic. The "cytokine storm" (CS) in COVID-19 leads to the worst stage of illness, and its timely control through immunomodulators, corticosteroids, and cytokine antagonists may be the key to reducing mortality. After reviewing published studies, we proposed a Cytokine Storm Score (CSs) to identify patients who were in this hyperinflammation state, and at risk of progression and poorer outcomes. We retrospectively analyzed 31 patients admitted to Infectious Disease Department in "St. Maria" Hospital in Terni with confirmed SARS-CoV-2 infections, and analyzed the "CS score" (CSs) and the severity of COVID-19. Then we conducted a prospective study of COVID-19 patients admitted after the definition of the CSscore. This is the first study that proposes and applies a new score to quickly identify COVID-19 patients who are in a hyperinflammation stage, to rapidly treat them in order to reduce the risk of intubation. CSs can accurately identify COVID-19 patients in the early stages of a CS, to conduct timely, safe, and effect administration of immunomodulators, corticosteroids, and cytokine antagonists, to prevent progression and reduce mortality.

Etiology of Severe Pneumonia in Children in Alveolar Lavage Fluid Using a High-Throughput Gene Targeted Amplicon Sequencing Assay

Objective: To evaluate the diagnostic value of a high-throughput gene targeted amplicon sequencing (TAS) assay for detecting pathogenic microorganisms in alveolar lavage fluid (ALF) from children with severe community-acquired pneumonia (SCAP). Methods: A retrospective study was performed on 48 frozen ALF samples from 47 severe pneumonia cases admitted to Children's Hospital of Fudan University from January 1, 2019, to March 31, 2019. All samples were tested by a multiplex PCR (Multi-PCR) assay and a TAS assay. The results of the TAS panels were parallel compared with Multi-PCR and Conventional Tests (CT) including culture, direct fluorescent antibody method (DFA), and singleplex polymerase chain reaction (PCR). Results: The proportion of pathogens detection by CT was 81.2% (39/48). The 8 common respiratory viruses including respiratory syncytial virus (RSV), adenovirus (ADV), influenza A virus (FLUA), influenza B virus (FLUB), parainfluenza virus 1-3 (PIV1-3), and human Metapneumovirus (hMPV) were found in 31.2% (15/48) of the 48 samples by DFA. With the criteria of CT results used as "Golden Standard" for determing of TAS results, the proportion of pathogens detection by TAS was 70.8% (34/48). The difference of proportion of pathogens detection between TAS and CT was not statistically significant (p = 0.232). The sensitivity and specificity of TAS for pathogens detection based on CT were 87.1% (95% CI, 71.77-95.18%) and 100.0% (95% CI, 62.88-100%), the positive predictive value (PPV) and negative predictive value (NPV) were 100.0% (95% CI, 87.35-100%) and 64.2% (95% CI, 35.62-86.02%), respectively. While Multi-PCR results were used as "Golden Standard," the total pathogens detection rate of TAS was 83.3% (40/48), which had a significant difference with that of Multi-PCR (p = 0.003). The sensitivity and PPV of TAS compared with Multi-PCR were 83.3% (95% CI, 69.23-92.03%) and 100.0% (95% CI, 89.08-100%), respectively. High rates of co-infection were proved by CT, Multi-PCR, and TAS. Mycoplasma pneumoniae (MP) and ADV were the two most frequently detected pathogens in all three assays. Conclusion: Compared with the CT and Multi-PCR methods, this TAS assay had a good performance in detecting bacteriological and viral pathogens from ALF. More research is needed to establish interpretation criteria based on TAS reads or analysis platforms.

Community-Acquired Pneumonia: A Focused Review

Community-acquired pneumonia (CAP) is a common cause for admission to the hospital and contributes significantly to patient morbidity and healthcare cost. We present a review of the epidemiology, pathophysiology, risk factors, symptoms, diagnosis, presentations, risk-stratification, markers, and management of CAP in the United States (US). The overall incidence of CAP is 16 to 23 cases per 1000 persons per year, and the rate increases with age. Some of the risk factors for CAP include comorbidities such as, chronic obstructive pulmonary disease (COPD), asthma, and heart failure. CAP symptoms vary, and typically include productive cough, dyspnea, pleuritic pain, abnormal vital signs (e.g., fever, tachycardia), and abnormal lung examination findings. A diagnosis can be made by radiography, which has the additional benefit of helping to identify patterns associated with typical and atypical CAP. There are risk-stratification calculators that can be used routinely by physicians to triage patients, and to determine adequate management. The Infectious Diseases Society of America (IDSA) and the American Thoracic Society (ATS) developed the Pneumonia Severity Index (PSI) which incorporates 20 risk factors to place patients into 5 classes correlated with mortality risk. In addition, the British Thoracic Society (BTS) established the original severity score CURB (confusion, uremia, respiratory rate, low blood pressure) to identify patients with CAP who may be candidates for outpatient vs. inpatient treatment. Inflammatory markers, such as procalcitonin (PCT), can be used to guide management throughout hospital stay. Antibiotic coverage will vary depending on whether outpatient vs. inpatient management is required.