Utility of measurement of interleukin-1ß and interleukin-8 in the diagnosis of complicated parapneumonic pleural effusions

Diagnostic value of soluble biomarkers for parapneumonic pleural effusion

Parapneumonic pleural effusion (PPE) is a common complication in patients with pneumonia. Timely and accurate diagnosis of PPE is of great value for its management. Measurement of biomarkers in circulating and pleural fluid have the advantages of easy accessibility, short turn-around time, objectiveness and low cost and thus have utility for PPE diagnosis and stratification. To date, many biomarkers have been reported to be of value for the management of PPE. Here, we review the values of pleural fluid and circulating biomarkers for the diagnosis and stratification PPE. The biomarkers discussed are C-reactive protein, procalcitonin, presepsin, soluble triggering receptor expressed on myeloid cells 1, lipopolysaccharide-binding protein, inflammatory markers, serum amyloid A, soluble urokinase plasminogen activator receptor, matrix metalloproteinases, pentraxin-3 and cell-free DNA. We found that none of the available biomarkers has adequate performance for diagnosing and stratifying PPE. Therefore, further work is needed to identify and validate novel biomarkers, and their combinations, for the management of PPE.

Pleural cytokines MIF and MIP-3α as novel biomarkers for complicated parapneumonic effusions and empyema

Patients with complicated parapneumonic effusion (CPPE)/empyema have high morbidity and mortality, particularly when adequate management is delayed. We aimed to investigate novel dysregulated cytokines that can be used as biomarkers for infectious pleural effusions, especially for CPPE/empyema. Expression of 40 cytokines in parapneumonic effusions (PPE) was screened in the discovery phase, involving 63 patients, using a multiplex immunobead-based assay. Six cytokines were subsequently validated by enzyme-linked immunosorbent assays (ELISAs). We then used ELISA to further evaluate the diagnostic values and cutoff values of these cytokines as potential biomarkers in an expanded group that included 200 patients with uncomplicated parapneumonic effusion (UPPE), CPPE, empyema, transudates, other exudates, and malignant pleural effusion (MPE). The pleural levels of four cytokines (MIF, MIP-3α, IL-1β, ENA-78) were highest and significantly increased in CPPE/empyema compared with those in other etiologies. According to receiver operating characteristic curve analysis, the four cytokines (MIF, MIP-3α, IL-1β, and ENA-78) had areas under the curve (AUCs) greater than 0.710 for discriminating parapneumonic pleural effusion from noninfectious pleural effusions. In a comparison of nonpurulent CPPE with UPPE, logistic regression analysis revealed that pleural fluid MIF ≥ 12 ng/ml and MIP-3α ≥ 4.3 ng/ml had the best diagnostic value; MIF also displayed the highest odds ratio of 663 for nonpurulent CPPE, with 97.5% specificity, 94.44% sensitivity, and an AUC of 0.950. In conclusion, our results show that elevated MIF and MIP-3α may be used as novel biomarkers for PPE diagnosis, particularly in patients with CPPE/empyema; the findings indicate that dysregulated cytokine expression may provide clues about the pathogenesis of pleural infection.

Cytokine levels predict 30-day mortality in octogenarians and nonagenarians with community-acquired pneumonia: a retrospective observational study

To analyze the value of cytokines (tumor necrosis factor [TNF]-α, interleukin [IL]-1β, IL-6, IL-8, IL-10) as predictors of mortality at 30 days in octogenarians and nonagenarians hospitalized in an internal medicine unit for community-acquired pneumonia (CAP). An observational, analytical, retrospective cohort study was conducted in the Department of Internal Medicine at Alicante General University Hospital between January 2014 and December 2015. Blood samples were frozen at - 80 °C, and cytokines were measured by ELISA. We included 115 patients, of whom 54% were men, with a mean age of 86.4 (standard deviation 4.5) years. There is a moderate correlation between IL-10 levels and CURB-65 score (p < 0.001) and a weak correlation with creatinine levels (p = 0.012) and urea levels (p = 0.032). Forty-five (39.1%) patients died within 30 days. In a multivariate analysis, the variables associated with mortality at 30 days were the following: age (adjusted odds ratio [ORa] 1.134, 95% confidence interval [CI] 1.02, 1.26), male sex (ORa 2.85, 95% CI 1.14, 7.14), IL-8 of 19 pg/mL or more (ORa 4.09, 95% CI 1.67, 10.01), and IL-10 of 11.29 pg/mL or more (ORa 4.00, 95% CI 1.58, 10.12). High IL-8 and IL-10 levels were shown to predict 30-day mortality in elderly patients with CAP. The inflammatory response in these patients seems to condition their prognosis. Further research in this line would provide more understanding about the physiopathological mechanisms and potential therapeutic targets for improving survival.

Combined serum biomarkers in the noninvasive diagnosis of complicated parapneumonic effusions and empyema

Background

We previously demonstrated that the pleural levels of proteins (neutrophil gelatinase-associated lipocalin/NGAL, calprotectin, bactericidal permeability-increasing/BPI, azurocidin 1/AZU-1) were valuable markers for identifying complicated PPE (CPPE). Herein, this study was performed to evaluate whether these proteins are useful as serological markers for identifying CPPE and empyema.

Methods

A total of 137 participates were enrolled in this study. The levels of NGAL, calprotectin, BPI and AZU-1 were measured in serum and pleural fluid by enzyme-linked immunosorbent assay. We also characterized the diagnostic values of these markers between different groups.

Results

The serum levels of NGAL, calprotectin, and BPI in PPE patients were significantly higher than those in transudates, noninfectious exudates, and healthy controls. The area under the curve (AUC) values of NGAL, calprotectin, and BPI for distinguishing PPE from transudates or noninfectious exudates were around 0.861 to 0.953. In PPE group, serum NGAL and calprotectin levels were significantly elevated in patients with CPPE and empyema than in those with UPPE, whereas the serum BPI levels were similar between these two groups. In CPPE and empyema patients, the serum NGAL showed a positive correlation with the pleural fluid NGAL (r = 0.417, p <  0.01). When combined with serum CRP, the sensitivity and specificity of serum calprotectin for identifying CPPE and empyema were the highest at 73.52% and 80.55%, respectively.

Conclusions

We concluded that serum calprotectin and NGAL were adjuvant serological markers for CPPE and empyema diagnosis. Patients present with pneumonia and pleural effusion signs in the chest x-ray and the combination of serum calprotectin and CRP constitutes a more highly sensitive and specific assay for identifying CPPE and empyema.

Electronic supplementary material

The online version of this article (10.1186/s12890-019-0877-8) contains supplementary material, which is available to authorized users.

[Place of biomarkers in the management of pulmonary infections]

INTRODUCTION

The management of acute lower respiratory tract infections and, in particular, the decision whether or not to commence antibiotic therapy, still remains difficult in the absence of reliable clinical or radiological criteria allowing confident distinction between bacterial and viral infections. Numerous biomarkers have been developed to help the clinician in his/her diagnostic and therapeutic approach, but the role and significance of each has not been clearly defined.

BACKGROUND

Though procalcitonin (PCT) or C-reactive protein (CRP) seem equal in helping the clinician to decide whether to commence antibiotic therapy or not during the course of an exacerbation of asthma or chronic obstructive pulmonary disease (COPD), PCT is currently the most useful biomarker to distinguish sepsis from other causes of inflammation and to determine the bacterial or viral origin of a pneumonia.

OUTLOOK

The ability of PCT to reduce the global exposure to antibiotics remains uncertain and the results of randomised trials are contradictory.

CONCLUSIONS

Prescription algorithms involving PCT may be used without increased risk for patients even though clinical signs of severity remain important. Changes in PCT also have a prognostic value in identifying those patients with unfavourable outcome.

Diagnosis of infectious pleural effusion using predictive models based on pleural fluid biomarkers

INTRODUCTION:

Diagnosis of pleural infection (PI) may be challenging. The purpose of this paper is to develop and validate a clinical prediction model for the diagnosis of PI based on pleural fluid (PF) biomarkers.

METHODS:

A prospective study was conducted on pleural effusion. Logistic regression was used to estimate the likelihood of having PI. Two models were built using PF biomarkers. The power of discrimination (area under the curve) and calibration of the two models were evaluated.

RESULTS:

The sample was composed of 706 pleural effusion (248 malignant; 28 tuberculous; 177 infectious; 48 miscellaneous exudates; and 212 transudates). Areas under the curve for Model 1 (leukocytes, percentage of neutrophils, and C-reactive protein) and Model 2 (the same markers plus interleukin-6 [IL-6]) were 0.896 and 0.909, respectively (not significant differences). However, both models showed higher capacity of discrimination than their biomarkers when used separately (P < 0.001 for all). Rates of correct classification for Models 1 and 2 were 88.2% (623/706: 160/177 [90.4%] with infectious pleural effusion [IPE] and 463/529 [87.5%] with non-IPE) and 89.2% (630/706: 153/177 [86.4%] of IPE and 477/529 [90.2%] of non-IPE), respectively.

CONCLUSIONS:

The two predictive models developed for IPE showed a good diagnostic performance, superior to that of any of the markers when used separately. Although IL-6 contributes a slight greater capacity of discrimination to the model that includes it, its routine determination does not seem justified.

Management of Parapneumonic Pleural Effusion in Adults

Pleural infections have high morbidity and mortality, and their incidence in all age groups is growing worldwide. Not all infectious effusions are parapneumonic and, in such cases, the organisms found in the pleural space are not the same as those observed in lung parenchyma infections. The diagnostic difficulty lies in knowing whether an infectious effusion will evolve into a complicated effusion/empyema, as the diagnostic methods used for this purpose provide poor results. The mainstays of treatment are to establish an early diagnosis and to commence an antibiotic regimen and chest drain as soon as possible. This should preferably be carried out with fine tubes, due to certain morphological, bacteriological and biochemical characteristics of the pleural fluid. Fluid analysis, particularly pH, is the most reliable method for assessing evolution. In a subgroup of patients, fibrinolytics may help to improve recovery, and their combination with DNase has been found to obtain better results. If medical treatment fails and surgery is required, video-assisted thoracoscopic surgery (VATS) is, at least, comparable to decortication by thoracotomy, so should only undertaken if previous techniques have failed. Further clinical trials are needed to analyze factors that could affect the results obtained, in order to define new evidence-based diagnostic and therapeutic strategies that provide more effective, standardized management of this disease.