Value of procalcitonin, C-reactive protein, and neopterin in exacerbations of chronic obstructive pulmonary disease

Prognostic value of procalcitonin in acute exacerbation of chronic obstructive pulmonary disease: A systematic review and meta-analysis

AIMS

To evaluate the prognostic role of procalcitonin(PCT) on all-cause mortality in acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

METHODS

Database including PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials were searched to find relevant trials. We included studies with patients hospitalized for AECOPD, which assessed procalcitonin levels and reported on the association between procalcitonin and mortality..

RESULTS

Fourteen trials involving 2983 patients were included. We found PCT levels in patients hospitalized for AECOPD are not associated with increased risk of mortality (RR 1.03, 95%CI 0.99-1.08). However, subgroup analysis showed PCT levels are indeed associated with an increased risk of mortality in mild to moderate AECOPD(RR 1.74, 95%CI 1.11-2.73). Deceased patients had significantly higher PCT levels, compared to survivors (MD 0.61, 95%CI 0.30-0.92). In PCT positive group, there was a significant increase in all-cause mortality(OR 3.21, 95%CI 1.84-5.61).

CONCLUSIONS

Results from this meta-analysis suggest that procalcitonin levels at the time of hospital admission for mild to moderate AECOPD are positively correlated with mortality.

Can the mucosal attacks of Behçet's disease be predicted?

The primary objective of this study was to investigate the association between disease activity and serum and salivary procalcitonin (Pct) levels in patients with Behçet's disease (BD). The study included patients diagnosed with BD and age-matched healthy volunteers (N: 48, N: 32). Serum and salivary Pct levels were quantified using enzyme-linked immunosorbent assay (ELISA) in the laboratories of Diskapi Yildirim Beyazit Training and Research Hospital. No significant disparity was observed in serum and salivary Pct levels between the patient and control groups (p > 0.05). Furthermore, there was no noteworthy correlation between disease activity and serum and salivary Pct values (p > 0.05). However, the serum Pct level in patients with active oral ulcers was significantly elevated compared to those without active oral ulcers (p: 0.003). Serum Pct emerges as a valuable marker for monitoring oral aphthous ulcer attacks within the patient population.

Functional capacity and inflammatory biomarkers as predictors for right atrial volume index in COPD patients

OBJECTIVE

Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality and right-heart complications. So, this study aimed to evaluate the role of right atrial volume index (RAVI), inflammatory biomarkers and functional capacity in predicting poor outcomes for patients with COPD, classified by COPD assessment test (CAT) questionnaire, as early predictors of right heart diseases.

METHODS

151 patients with COPD with ejection fraction (LVEF) > 55% were enrolled and classified according to CAT questionnaire into CAT ≥ 10 (group I) and CAT < 10 (group II). RAVI was calculated using Echocardiography. Assessment of RV systolic function was done by Doppler imaging. Functional capacity parameters were assessed by modified medical research council dyspnea scale (mMRC). IL-1β, adiponectin, hs-CRP and neopterin were evaluated by ELSA kits.

RESULTS

Group I (CAT ≥ 10) had higher RAVI (73.92 ± 21.20 ml/m2 vs 22.73 ± 6.24 ml/m2, p < 0.001), lower S`tri (0.05 ± 0.01 vs 0.13 ± 0.03 m/s, p < 0.001), lower tricuspid annular plane systolic excursion (TAPSE) (1.20 ± 0.17 cm vs 2.17 ± 0.48 cm, p < 0.001), higher RVSP (54.88 ± 7.97 vs 26.79 ± 9.84 mmHg, p < 0.001) compared with group II (CAT < 10). RAVI was good predictor of CAT (r = 0.954, p < 0.001) and strongly correlated with tricuspid S`tri, RVSP, tricuspid E/e' and Mitral E/e' (r = -0.737, r = 0.753, r = 0.817 and r = 0.515, respectively, p < 0.001). RAVI was correlated with TAPSE (r = -0.673, p < 0.001) and with tricuspid E/A ratio & LVEF (r = 0.628, r = -0.407, respectively, p < 0.001). Hs-CRP: 2.50 ± 1.43 vs 2.03 ± 1.19, IL-1β: 37.96 ± 14.35 vs 27.57 ± 8.06, neopterin: 91.37 ± 17.30 vs 76.90 ± 16.75, p < 0.05) were significantly higher besides lower adiponectin levels (3.19 ± 1.98 vs 5.32 ± 1.33 p < 0.05) in group I as compared to group II.

CONCLUSION

Functional capacity might be useful predictor for right heart diseases in COPD patients. Inflammatory biomarkers, low adiponectin and high Hs-CRP, IL-1β and neopterin levels, might not only be useful to monitor treatment response but may also help to discriminate patients with a worsen prognosis.

Incorporating Biomarkers in COPD Management: The Research Keeps Going

Globally, chronic obstructive pulmonary disease (COPD) remains a major cause of morbidity and mortality, having a significant socioeconomic effect. Several molecular mechanisms have been related to COPD including chronic inflammation, telomere shortening, and epigenetic modifications. Nowadays, there is an increasing need for novel therapeutic approaches for the management of COPD. These treatment strategies should be based on finding the source of acute exacerbation of COPD episodes and estimating the patient’s own risk. The use of biomarkers and the measurement of their levels in conjunction with COPD exacerbation risk and disease prognosis is considered an encouraging approach. Many types of COPD biomarkers have been identified which include blood protein biomarkers, cellular biomarkers, and protease enzymes. They have been isolated from different sources including peripheral blood, sputum, bronchoalveolar fluid, exhaled air, and genetic material. However, there is still not an exclusive biomarker that is used for the evaluation of COPD but rather a combination of them, and this is attributed to disease complexity. In this review, we summarize the clinical significance of COPD-related biomarkers, their association with disease outcomes, and COPD patients’ management. Finally, we depict the various samples that are used for identifying and measuring these biomarkers.

Alterations in biochemical markers in adenovirus infection

BACKGROUND

Analyze possible relationships between HAdV and markers for inflammation, specifically the C-reactive protein (CRP) and procalcitonin (PCT) tests, along with other haematological markers.

METHODS

Retrospective study of 487 children presenting with fever and/or acute respiratory symptoms in the Paediatric Emergency Department. Analyses included viral presence/absence (both HAdV and other respiratory viruses) in respiratory exudates, CRP and PCT alterations in plasma, and haematological markers in whole blood.

RESULTS

Viral load was >500 copies/10³ cells of HAdV in 127 cases (26.1%), of which 66 (52%, P<0.0001) had alterations in PCT, and 112 (88.1%, P<0.0001) in CRP. Haematological markers were similar either HAdV was present or not, although many HAdV positive patients demonstrated leukocytosis (66%). Bacterial cultures from 141 samples showed altered PCT in 27 (60%) with HAdV infection, in 3 (18.7%) with bacterial infection, and 13 (26.5%) without either viral or bacterial infection (P<0.05). CRP was altered in 88.9% of HAdV infected children and in 87% infected with bacteria, although the percentage was greater than in cases where other respiratory viruses were present (61.3% P<0.05).

CONCLUSIONS

Results demonstrate a clear relationship between HAdV infection and alterations in PCT and CRP which should be taken into account in paediatric patient management.

Procalcitonin for Antibiotic Prescription in Chronic Obstructive Pulmonary Disease Exacerbations: Systematic Review, Meta-Analysis, and Clinical Perspective

The 2020 Global Initiative for Obstructive Lung Disease report indicates that the blood biomarker procalcitonin (PCT) may assist in decision-making regarding the initiation of antibiotics for chronic obstructive pulmonary disease (COPD) exacerbations. PCT is an acute-phase reactant that increases in response to inflammation and infection, and has been studied in various bacterial infections for initiation and de-escalation of antibacterials. The purpose of this systematic review and meta-analysis was to evaluate the strength of the data on the use of PCT to guide antibiotic prescription in COPD exacerbations. Among the randomized clinical trials included in our meta-analysis, almost all of which were conducted exclusively in the hospital setting. PCT was found to decrease overall antibiotic exposure in COPD exacerbations by 2.01 days (p = 0.04), while no apparent effects were found on clinical outcomes (length of hospital stay, p = 0.88; treatment failure p = 0.51; all-cause mortality p = 0.28). However, the majority of blood PCT levels in COPD exacerbations were below the manufacturer-recommended cutoff for antibiotics, and the use of this marker was associated with worse outcomes in the intensive care setting. Further, based on additional sensitivity analysis excluding studies with high risk of bias or with converted outcome value, the effect of PCT on antibiotic duration in RCTs was no longer significant (MD = -1.88 days, 95% CI [-3.95, 0.19] days, p = 0.08, and MD = -1.72 days, 95% CI [-4.28, 0.83] days, p = 0.19, respectively). Our review and analysis does not support the use of PCT to guide antibiotic prescription in COPD exacerbations.

Clinical value of IL-13 and ECP in the serum and sputum of eosinophilic AECOPD patients

IMPACT STATEMENT

Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is an inevitable trend in the development of the disease and eosinophils (EOS) participate in inflammation process. It is important to explore some relatively simple biomarkers in AECOPD which are useful to recognize the disease. In the present study, 108 hospitalized patients with AECOPD were collected and the levels of IL-13 and ECP in the serum and sputum were measured. The levels of IL-13 and ECP in sputum in the eosinophilic group were higher than those in the noneosinophilic group. Moreover, the noneosinophilic group had a higher rate of rehospitalization due to acute exacerbation during the one-year follow-up. The results show that eosinophils in peripheral blood are a simple, convenient, and inexpensive index for assessing the condition and prognosis of AECOPD patients. IL-13 and ECP are involved in the pathogenesis of eosinophilic AECOPD and may be the new targeted anti-inflammatory therapies.

Unique natural killer cell subpopulations are associated with exacerbation risk in chronic obstructive pulmonary disease

Chronic Obstructive Pulmonary Disease (COPD) is the third leading cause of death worldwide. COPD is frequently punctuated by acute exacerbations that are precipitated primarily by infections, which increase both morbidity and mortality and inflates healthcare costs. Despite the significance of exacerbations, little understanding of immune function in COPD exacerbations exists. Natural killer (NK) cells are important effectors of innate and adaptive immune responses to pathogens and NK cell function is altered in smokers and COPD. Using high-dimensional flow cytometry, we phenotyped peripheral blood NK cells from never smokers, smokers, and COPD patients and employed a non-supervised clustering algorithm to define and detect changes in NK cell populations. We identified greater than 1,000 unique NK cell subpopulations across patient groups and describe 13 altered NK populations in patients who experienced prior exacerbations. Based upon cluster sizes and associated fluorescence data, we generated a logistic regression model to predict patients with a history of exacerbations with high sensitivity and specificity. Moreover, highly enriched NK cell subpopulations implicated in the regression model exhibited enhanced effector functions as defined by in vitro cytotoxicity assays. These novel data reflect the effects of smoking and disease on peripheral blood NK cell phenotypes, provide insight into the potential immune pathophysiology of COPD exacerbations, and indicate that NK cell phenotyping may be a useful and biologically relevant marker to predict COPD exacerbations.

Serum procalcitonin levels in chronic obstructive pulmonary disease patients in North Indian Population

Background

Exacerbations in Chronic obstructive pulmonary disease (COPD) have a considerable impact on morbidity, mortality, and quality of life. Procalcitonin (PCT) a polypeptide normally produced in neuroendocrine cells of the thyroid and lungs is a marker of systemic inflammation and bacterial infection.

Objectives

The aim of this study was to determine the levels of PCT in serum of acute exacerbation of COPD patients (AECOPD) and stable COPD patients in North Indian population.

Materials and Methods

The study was conducted on 80 AECOPD and 80 stable COPD patients in respiratory medicine department at tertiary care hospital in north India. PCT levels were measured in serum by ELISA kit. GraphPad Prism version 6.01 (GraphPad software Inc.; La, Jolla, CA, USA) was used for analysis of data.

Results

The present study showed that mean serum PCT levels were significantly higher in AECOPD group (1.31 ± 0.79) as compared to stable COPD group (0.1 ± 0.09) (P < 0.001).

Conclusion

The study confirms that PCT levels were higher in AECOPD patients as compared to stable COPD patients. PCT could be used as a biomarker of exacerbations of COPD and can be used to target management and guiding the treatment in patients with acute exacerbations of COPD.

Bacterial infections in acute exacerbation of chronic obstructive pulmonary disease: a systematic review and meta-analysis

OBJECTIVE

Due to the importance of Chronic obstructive pulmonary disease (COPD) as the fourth cause of mortality worldwide and the lack of studies evaluating the prevalence of bacterial infections in disease exacerbation, this systematic review and meta-analysis was performed to determine the prevalence rate of bacterial infections in COPD patients.

METHODS

PubMed, ISI Web of Science, and Scopus databases were systematically searched for population-based prevalence studies (1980-2018). MeSH terms for "Bacterial infections" and "AECOPD" were used as search keywords. The selected studies were filtered according to the inclusion and exclusion criteria. Fixed and random-effects models were used for estimation of summary effect sizes. Between-study heterogeneity, as well as publication bias, were calculated.

RESULTS

Finally, 118 out of 31,440 studies were selected. The overall estimation of the prevalence of bacterial infection was 49.59% [95% confidence interval (CI) 0.4418-0.55]. The heterogeneity in estimating the pooled prevalence of bacterial infections was shown in the studies (Cochran Q test: 6615, P < 0.0001, I² = 98.23%). In addition, S. pneumoniae, H. influenzae, M. catarrhalis, A. baumannii, P. aeruginosa, and S. aureus were the most prevalent reported bacteria.

CONCLUSIONS

Our results as the first meta-analysis for the issue demonstrated that bacterial infections are an important risk factor for AECOPD. Further studies must be performed for understanding the exact role of bacterial agents in AECOPD and help physicians for more applicable preventive and therapeutic measurements.

Inflammatory Markers in Patients Using Domiciliary Non-invasive Mechanical Ventilation: C Reactive Protein, Procalcitonin, Neutrophil Lymphocyte Ratio

Aim: Early identification and treatment of infections in patients using domiciliary non-invasive mechanical ventilation (NIMV) due to chronic respiratory failure (CRF) can reduce hospital admissions. We assessed C-reactive protein (CRP), procalcitonin, and neutrophil lymphocyte ratio (NLR) as indicators of infection/inflammation.

Methods: The study was designed as a retrospective, observational, cross-sectional study, and was performed in 2016 in an intensive care unit outpatient clinic in patients using NIMV. Patients who came to the outpatient clinic with dyspnea, increased sputum, increased prothrombin, and who had hemogram, procalcitonin, and serum CRP, NLR, and PLT/MPV levels assessed, were enrolled into the study. Demographic characteristics, co-morbid diseases, respiratory symptoms, hemogram, biochemistry, CRP, and procalcitonin values in stable and acute attack patients were recorded from patient files. The descriptive statistics and CRP, NLR, and procalcitonin values were assessed.

Results: During the study period, 49 patients (24 female) with chronic obstructive pulmonary disease (COPD, n = 24), obesity hypoventilation syndrome (OHS, n = 15), or interstitial lung disease, n = 10), and having had three inflammatory markers assessed, were included in the study. Their mean age was 67 (SD ± 12). Stable patients vs. those who had an acute attack was 41 vs. eight, and within 7 days of outpatient admission four patients were hospitalized. CRP, NLR, and PLT/MPV values were similar in patients' who had sputum purulence, and an increase in dyspnea and sputum, but procalcitonin was significantly higher in patients who had an acute attack. Procalcitonin was not correlated with CRP, NLR, and PLT/MPV.

Conclusions: Patients with CRF had similar levels of CRP and NLR during a stable and acute attack state. Procalcitonin may be a better marker for therapeutic decisions in advanced chronic inflammatory diseases.

Neutrophil to lymphocyte ratio is a better indicator of COPD exacerbation severity in neutrophilic endotypes than eosinophilic endotypes

Background

Complete blood count parameters provide novel inflammatory markers, namely neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR). We aimed to assess any differences in these novel inflammatory markers according to exacerbation severity in patients with COPD in both eosinophilic and neutrophilic endotypes.

Method

This retrospective cross-sectional study was conducted at a tertiary education hospital. Previously diagnosed COPD patients admitted to the hospital with acute COPD exacerbation (AECOPD) were enrolled into the study. Patients were grouped according to COPD endotype, eosinophilic (peripheral blood eosinophil rate ≥2%) and neutrophilic (peripheral blood eosinophil rate <2%), and further subdivided according to place of admission (outpatient clinic, ward, or intensive care unit [ICU]) as an indicator of disease severity. Complete blood count, biochemistry, C-reactive protein (CRP), NLR, PLR, and platelet to mean platelet volume values were recorded from an electronic hospital database system and compared among all groups.

Results

Of the 10,592 patients included in the study, 7,864 were admitted as outpatients, 2,233 to the wards, and 495 to ICU. Neutrophilic COPD patients (n=6,536, 62%) had increased inflammatory markers compared with eosinophilic COPD patients (n=4,056, 38%); median NLR was 5.11 vs 2.62 (P<0.001), PLR was 175.66 vs 130.00 (P<0.001), and CRP was 11.6 vs 7.7 (P<0.001). All values increased relative to admission to the outpatient clinic, ward, or ICU: median NLR was 3.20, 6.33, and 5.94, respectively, median PLR was 140.43, 208.46, and 207.39, respectively, and median CRP was 6.4, 15.0, and 22.8, respectively. The median NLR values of patients in outpatients/ward/ICU increased in neutrophilic and eosinophilic endotypes: 4.21/7.57/8.60 (P<0.001) and 2.50/3.43/3.42 (P=0.81), respectively. CRP showed a similar increased pattern according to severity of AECOPD endotypes.

Conclusion

In COPD exacerbation, the inflammatory markers show different increases in each COPD endotypes. These findings may be crucial for defining exacerbation endotypes, the severity of exacerbation, and treatment response during follow-up in COPD patients.

The Use of Serum Procalcitonin as a Diagnostic and Prognostic Biomarker in Chronic Obstructive Pulmonary Disease Exacerbations: A Literature Review Update

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are a major complication in COPD patients which can be triggered by bacterial or viral infections, environmental pollutants and other causes. Procalcitonin (PCT), a peptide that markedly increases in cases of bacterial infection, has been extensively investigated as a biomarker in the diagnosis, prognosis and treatment in patients with AECOPD. A number of studies published in the last decade, tried to investigate whether PCT levels can differentiate between bacterial and other causes of exacerbations, if they can be used as a guide for optimal antibiotic therapy and if they can be a tool in the assessment of the severity and the need for further interventions in the management of those patients. This review aims to gather, summarize and critically present all the available data to date.

Comparison of efficiency of inhaled and intravenous corticosteroid on pregnant women with COPD and the effects on the expression of PCT and hs-CRP

The efficiency of inhaled and systemic corticosteroids on pregnant women with chronic obstructive pulmonary disease (COPD) was investigated. The study also compared the effects of the administration on the expression of inflammatory mediator procalcitonin (PCT) and high-sensitivity C-reactive protein (hs-CRP). A total of 120 pregnant COPD patients were recruited and randomly allocated into the following three groups: Intravenous corticosteroid treatment group (n=42), inhaled corticosteroid treatment group (n=38), and control group (without any corticosteroid treatment, n=40). Patients of the all three groups received symptomatic supportive treatments including oxygen therapy, anti-infection therapy, expectorant, and bronchodilator. The serum PCT and hs-CRP expression levels were measured before treatment and after 7 days of treatment. Moreover, the clinical parameters such as symptoms, blood gas analysis parameters, pulmonary function indexes, fasting blood glucose (FBG) and adverse reactions were recorded. The overall clinical effective rates of the group received budesonide inhalation and the group receiving systemic methylprednisolone treatment were comparable. Both treatments were able to reduce the levels of inflammatory mediators, hs-CRP and PCT. On the other hand, treatments increased PaO₂ of arterial blood gas while reducing PaCO₂, thereby improving the lung function (FEV1% pred and FEV1/FVC) (P>0.05). The study observed that the FBG levels in COPD patients receiving systemic corticosteroid treatment were significantly increased, while budesonide inhalation did not significantly affect the FBG levels. In addition, rates of adverse events (such as mouth dry, oral ulcers, hoarseness) of systemic corticosteroid treatment group were significantly higher than those in inhaled corticosteroid treatment group and control group (38.1% vs. 17.5% vs. 5.0%, comparison between groups: P<0.05). In conclusion, inhaled and systemic use of corticosteroid both significantly improved dyspnea and other clinical symptoms of pregnant COPD patients by increasing oxygen partial pressure, correcting hypoxemia, and enhancing lung function. Moreover, fewer adverse reactions were observed with inhaled corticosteroid treatment, suggesting that inhaled administration is a relatively good, safe and effective treatment for pregnant COPD patients.

Comparison of procalcitonin, C-reactive protein, white blood cell count and clinical status in diagnosing pneumonia in patients hospitalized with acute exacerbations of COPD: A prospective observational study

Lower respiratory tract infection is the most common cause of acute exacerbations of chronic obstructive pulmonary disease (AECOPD). The aim of the present study was to compare the accuracy of procalcitonin (PCT), C-reactive protein (CRP) and white blood cell count (WBC) as single diagnostic tests and in combination with clinical signs and symptoms to diagnose pneumonia in patients hospitalized with AECOPD. This was a prospective, single centre observational study. Patients with spirometry-confirmed COPD who were hospitalized due to AECOPD were consecutively recruited at the hospital's Emergency Unit. Pneumonia was defined as a new pulmonary infiltrate on chest X-ray. The values of PCT, CRP and WBC were determined at admission. Receiver operating characteristic (ROC) curve analysis was used to study the accuracy of various diagnostic tests. Of the 113 included patients, 35 (31%) had pneumonia at admission. Area under the ROC curve (AUC) for PCT, CRP and WBC as a single test to distinguish between patients with and without pneumonia was 0.67 (95% CI 0.55-0.79), 0.73 (95% CI 0.63-0.84) and 0.67 (95% CI 0.55-0.79), respectively ( p = 0.42 for the test of difference). The AUC for a model of clinical signs and symptoms was 0.84 (95% CI 0.76-0.92). When biomarkers were added to the clinical model, the AUCs of the combined models were not significantly different from that of the clinical model alone ( p = 0.54). PCT had about the same accuracy as CRP and WBC in predicting pneumonia in patients hospitalized with AECOPD both as a single test and in combination with clinical signs and symptoms.

Effect of Pingchuan Guben decoction on patients with chronic obstructive pulmonary disease: Results from a randomized comparative effectiveness research trial

Chronic obstructive pulmonary disease (COPD) is known to be a systemic low-grade ongoing inflammation exerting major health and economic burden worldwide. Complementary and alternative medicines, such as Traditional Chinese Medicine, are widely used for the treatment of patients with COPD. The present study was designed to investigate the efficacy of Pingchuan Guben decoction on patients with COPD through a double-blinded, open-labeled, randomized controlled trial. A total of 86 patients were randomly assigned to two groups, with 43 patients in the intervention group and 43 cases in the control group. The patients in the control group were treated with conventional western medicine, and the intervention group received a combination of conventional western medicine and Pingchuan Guben decoction. After 12 weeks of treatment, the mean 6-minute walking distance, forced expiratory volume in 1 sec (FEV1), forced vital capacity (FVC) and FEV1/FVC in the intervention group were significantly higher than those of the control group (P<0.05). The levels of inflammation factors and protease molecules were significantly ameliorated in the intervention group compared with the control group (P<0.05). The levels of Kelch-like ECH-associated protein 1 (Keap1), nuclear factor-E2-related factor-2 (Nrf2), superoxide anions, malondialdehyde, glutathione S-transferase and glutathione peroxidase were significantly more improved in the intervention group compared with those in the control group over the 12-week study period (P<0.05). Therefore, combinations of western medicine with Pingchuan Guben decoction may exert therapeutic effects on patients with COPD via modulations of inflammation factors and protease molecules, as well as the activation of the Keap1/Nrf2 signaling pathway.

Serum inflammatory biomarkers and clinical outcomes of COPD exacerbation caused by different pathogens

BACKGROUND AND OBJECTIVE

COPD exacerbation is characterized by worsening of symptoms, warranting change in treatment. Systemic and airway inflammation play roles in the pathogenesis of COPD exacerbation. We hypothesized whether increased serum inflammatory biomarkers are associated with the clinical outcomes of COPD exacerbation caused by different infectious pathogens.

METHODS

COPD patients with exacerbation were recruited from a hospital emergency department during 2014-2015. Serum procalcitonin (PCT) and C-reactive protein (CRP) were measured. Dyspnea, eosinopenia, consolidation, acidemia, and atrial fibrillation (DECAF) score was calculated for predicting mortality. Multiplex polymerase chain reaction was carried out for respiratory viral assay from nasopharyngeal swabs, and sputum bacterial culture was also performed. Hospital mortality, invasive mechanical ventilation requirement, and length of hospital stay (LOS) were evaluated, and their associations with clinical characteristics, DECAF score, and serum biomarkers were examined.

RESULTS

A total of 62 COPD patients were enrolled. These patients were classified as Global Initiative for Obstructive Lung Disease (GOLD) stage 2, 3, and 4 in 12.9%, 6.4%, and 80.7% of cases, respectively. Isolated bacterial exacerbation was recovered in 30.6% of exacerbation episodes: Klebsiella pneumoniae was the most commonly identified bacteria. Viral pathogens and coinfections were noted in 9.6% and 16.1% of exacerbated patients, respectively. Influenza was the most commonly detected viral pathogen. Serum biomarkers and DECAF score for viruses, bacteria, coinfection, and noninfectious causes of exacerbations were similar. Neither DECAF score nor serum biomarkers were able to differentiate patients with and without mortality or requiring mechanical ventilation. Increased serum PCT was noted in patients with LOS ≥7 days when compared with those with LOS <7 days (0.38 ng/mL vs 0.1 ng/mL; P=0.035).

CONCLUSION

Increased serum PCT is associated with longer LOS in COPD exacerbation. However, CRP and DECAF score play limited roles in predicting clinical outcome and lack an association with causes of exacerbation.

Procalcitonin and CRP as Biomarkers in Discrimination of Community-acquired Pneumonia and Exacerbation of COPD

Background

Serum procalcitonin (PCT) and C-reactive protein (CRP) are markers of systemic inflammation and bacterial infection. We aimed to compare the usefulness of procalcitonin and CRP in patients with community-acquired pneumonia and exacerbations of chronic obstructive pulmonary disease (COPD).

Methods

A total of 116 consecutive patients were included in the study: 76 with chronic obstructive pulmonary disease in group 1, and 40 with pneumonia in group 2.

Results

Median serum CRP level was 44 mg/L in the COPD group and 132 mg/L in the pneumonia group. Median value of serum PCT was found to be 0.07 in the COPD group and 0.14 ng/mL in the pneumonia group. Serum PCT and CRP levels were significantly higher in the pneumonia group compared to the COPD group (p<0.001). The area under the ROC curve was 0.788 (CI: 0.704–0.872) for CRP and 0.699 (CI: 0.599–0.800) for procalcitonin to identify pneumonia.

Conclusions

Procalcitonin and CRP levels were significantly higher in patients with community-acquired pneumonia presenting to the emergency department with indications for hospitalization than in patients with exacerbations of chronic obstructive pulmonary disease. Serum CRP and procalcitonin concentrations were strongly correlated. CRP might be a more valuable marker in these patients with lower respiratory tract infections.

The recent advances of phenotypes in acute exacerbations of COPD

Exacerbations of COPD are clinically relevant events with therapeutic and prognostic implications. Yet, significant heterogeneity of clinical presentation and disease progression exists within acute exacerbations of COPD (AECOPD). Currently, different phenotypes have been widely used to describe the characteristics among patients with AECOPD. This has proved to be significant in the treatment and prediction of the outcomes of the disease. In this review of published literature, the phenotypes of AECOPD were classified according to etiology, inflammatory biomarkers, clinical manifestation, comorbidity, the frequency of exacerbations, and so on. This review concentrates on advancements in the use of phenotypes of AECOPD.

A Systematic Review of Diagnostic Biomarkers of COPD Exacerbation

The aims of this systematic review were to determine which blood-based molecules have been evaluated as possible biomarkers to diagnose chronic obstructive pulmonary disease (COPD) exacerbations (AECOPD) and to ascertain the quality of these biomarker publications. Patients of interest were those that have been diagnosed with COPD. MEDLINE, EMBASE, and CINAHL databases were searched systematically through February 2015 for publications relating to AECOPD diagnostic biomarkers. We used a modified guideline for the REporting of tumor MARKer Studies (mREMARK) to assess study quality. Additional components of quality included the reporting of findings in a replication cohort and the use of receiver-operating characteristics area-under-the curve statistics in evaluating performance. 59 studies were included, in which the most studied biomarkers were C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). CRP showed consistent elevations in AECOPD compared to control subjects, while IL-6 and TNF-α had variable statistical significance and results. mREMARK scores ranged from 6 to 18 (median score of 13). 12 articles reported ROC analyses and only one study employed a replication cohort to confirm biomarker performance. Studies of AECOPD diagnostic biomarkers remain inconsistent in their reporting, with few studies employing ROC analyses and even fewer demonstrating replication in independent cohorts.

Mental health, serum biomarkers and survival in severe COPD: a pilot study

Background

Chronic obstructive pulmonary disease (COPD) impairs physical status and impacts on mental health. This prospective study was designed to assess associations between mental health and systemic biomarkers, and their combined relationship with long-term survival in stable severe COPD.

Methods

Forty-five patients with severe but stable COPD (forced expiratory volume in 1 s of 29.8 (quartiles: 22.6; 41.4) %predicted) were assessed using the Hospital Anxiety and Depression Scale (HADS), the Patient Health Questionnaire (PHQ), St. George’s Respiratory Questionnaire and the State-Trait Anxiety Inventory (STAI). The following serum biomarkers were measured: 25-OH-cholecalciferol, C-reactive protein, erythrocyte sedimentation rate, leucocyte number, serum amyloid-A (SA-A), N-terminal pro-brain natriuretic peptide, troponin I, glycosylated haemoglobin, haemoglobin (Hb), haematocrit (Hc), creatinine and thyroid-stimulating hormone. Patients were followed-up for 36 months. Associations between aspects of mental health and biomarkers, and their utility as predictors of 3-year survival were evaluated by regression analyses.

Results

The prevalence of anxiety (HADS-A: 89.9 %), depression (HADS-D: 58.8 %; PHQ: 60.6 %), somatisation (PHQ-15: 81.8 %) and psychosocial stress (PHQ-stress: 60.6 %) was high. There was a significant positive association between the leucocyte count and SA-A level with STAI-trait anxiety (p = 0.03 and p = 0.005, respectively), and between leucocytes and PHQ-stress (p = 0.043). Hb and Hc were significantly negatively associated with HADS-depression (p = 0.041 and p = 0.031, respectively). Univariate Cox regression analyses revealed that leucocyte count (hazard ratio (HR) 2.976, 95 % CI 1.059-8.358; p = 0.038), and stress (HR 4.922, 95 % CI 1.06–22.848; p = 0.042) were linked to long-term survival. In multivariate Cox regression analyses, including known risk factors for survival in COPD, PHQ-stress (HR 45.63, 95 % CI 1.72–1,208.48; p = 0.022) remained significantly associated with survival.

Conclusion

In this pilot study different dimensions of mental health were correlated to serum biomarkers, probably reflecting systemic effects of COPD. While leucocyte number and PHQ-stress were associated with long-term survival in univariate analyses, PHQ-stress remained in multivariate analyses as independent prognostic factor.

Measurement of C-reactive protein, procalcitonin and neutrophil elastase in saliva of COPD patients and healthy controls: correlation to self-reported wellbeing parameters

BACKGROUND

Saliva is increasingly promoted as an alternative diagnostic bio-sample to blood; however its role in respiratory disease requires elucidation. Our aim was to investigate whether C-reactive protein (CRP), procalcitonin (PCT) and neutrophil elastase (NE) could be measured in unstimulated whole saliva, and to explore differences between COPD patients and controls with normal lung function. We also determined the relationship between these salivary biomarkers and self-reported COPD-relevant metrics.

METHODS

Salivary CRP, PCT and NE levels were measured at each of 3 visits over a 14-day period alongside spirometry and a daily self-assessment dairy in 143 subjects: 20 never-smokers and 25 smokers with normal spirometry; 98 COPD patients [GOLD Stage I, 16; Stage II, 32; Stage III, 39; Stage IV, 11]. Twenty-two randomly selected subjects provided simultaneous blood samples.

RESULTS

Levels of each salivary biomarker could distinguish between the above cohorts. Significant differences remained for salivary CRP and NE (p < 0.05) following adjustment for age, gender, sampling time, gum disease and total co-morbidities; but not for BMI except for salivary NE, which remained higher in smokers compared to non-smokers and stable COPD subjects (p < 0.001). Patients with acute COPD exacerbations had a median increase in all 3 salivary biomarkers (p < 0.001); CRP: median 5.74 ng/ml, [interquartile range (IQR) 2.86-12.25], PCT 0.38 ng/ml, [IQR 0.22-0.94], and NE 539 ng/ml, [IQR 112.25-1264]. In COPD patients, only salivary CRP and PCT levels correlated with breathing scores (r = 0.14, p < 0.02; r = 0.13, p < 0.03 respectively) and sputum features but not with activities of daily living. Salivary CRP and PCT concentrations strongly correlated with serum counterparts [r = 0.82, (95% CI: 0.72-0.87), p < 0.001 by Spearman's; and r = 0.53, (95% CI: 0.33-0.69), p < 0.006 respectively]; salivary NE did not.

CONCLUSIONS

CRP, PCT and NE were reliably and reproducibly measured in saliva, providing clinically-relevant information on health status in COPD; additionally NE distinguished smoking status. All 3 salivary biomarkers increased during COPD exacerbations, with CRP and PCT correlating well with patient-derived clinical metrics. These results provide the conceptual basis for further development of saliva as a viable bio-sample in COPD monitoring and exacerbation management.

When should acute exacerbations of COPD be treated with systemic corticosteroids and antibiotics in primary care: a systematic review of current COPD guidelines

Not all patients with acute exacerbations of chronic obstructive pulmonary disease (COPD) benefit from treatment with systemic corticosteroids and antibiotics. The aim of the study was to identify criteria recommended in current COPD guidelines for treating acute exacerbations with systemic corticosteroids and antibiotics and to assess the underlying evidence. Current COPD guidelines were identified by a systematic literature search. The most recent guidelines as per country/organisation containing recommendations about treating acute exacerbations of COPD were included. Guideline development and criteria for treating acute exacerbations with systemic corticosteroids and antibiotics were appraised. Randomised controlled trials directly referred to in context with the recommendations were evaluated in terms of study design, setting, and study population. A total of 19 COPD guidelines were included. Systemic corticosteroids were often universally recommended to all patients with acute exacerbations. Criteria for treatment with antibiotics were mainly an increase in respiratory symptoms. Objective diagnostic tests or clinical examination were only rarely recommended. Only few criteria were directly linked to underlying evidence, and the trial patients represented a highly specific group of COPD patients. Current COPD guidelines are of little help in primary care to identify patients with acute exacerbations probably benefitting from treatment with systemic corticosteroids and antibiotics in primary care, and might contribute to overuse or inappropriate use of either treatment.

Comparison of diagnostic values of procalcitonin, C-reactive protein and blood neutrophil/lymphocyte ratio levels in predicting bacterial infection in hospitalized patients with acute exacerbations of COPD

BACKGROUND

Viral or bacterial upper respiratory infections are the most common cause of acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Based on available data, no reliable parameter has been presented to distinguish between bacterial and nonbacterial exacerbations. Therefore, we compared the diagnostic value of procalcitonin (PCT) level, which is a newer marker for predicting bacterial infections in patients with AECOPD, to routine parameters such as C-reactive protein (CRP) levels and the neutrophil/lymphocyte (N/L) ratio.

METHODS

This study included all consecutive patients who were admitted for a diagnosis of AECOPD between January 1 and March 31, 2014. PCT, CRP, and the N/L ratio were assessed in addition to cultures from tracheal aspirates or sputum on the first day of admission. Patients with a pneumonic infiltration on chest radiographs, or an extrapulmonary infection focus, or whose blood samples were not obtained for PCT and/or CRP at the same time as sputum culture were excluded from the study.

RESULTS

A total of 77 patients were included with a mean age of 71.7 ± 9.5 years. Bacteria were isolated in 37.4 % of the patients. Mean PCT levels were significantly higher in patients with positive sputum cultures than in patients with negative sputum cultures. The cut-off values for PCT, CRP, and the N/L ratio for predicting a bacterial infection were 0.40 ng/mL, 91.50 mg/L, and 11.5, respectively; sensitivity was 61, 54, and 61 % respectively; specificity was 67, 52, and 58 %, respectively; and the area under the curve (AUC) values were 0.64, 0.52, and 0.58, respectively. The AUC value of PCT was significantly better for predicting bacterial infection compared with the CRP level or the N/L ratio (p = 0.042).

CONCLUSION

PCT was better than CRP and the N/L ratio for predicting a bacterial infection in hospitalized patients with AECOPD. However, we find PCT not so reliable in predicting bacterial infection in AECOPD due to sensitivity and specificity of less than 80 % and a low AUC value.

C-reactive protein measurements as a marker of the severity of chronic obstructive pulmonary disease exacerbations

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease of the lungs. Acute exacerbations of COPD (AE-COPD) are a result of infectious or non-infectious instances. In our study, we aimed to determine whether serum C-reactive protein (CRP) levels are predictive indicators for disease severity and prognosis in hospitalized patients with AE-COPD. A total of 64 patients (36 regular ward and 28 ICU patients) were included in the study. Cases were identified and classified according to the Global Initiative for COPD. The first CRP test levels at acceptance at the ward or intensive care unit were counted in the study. CRP levels of patients in intensive care were significantly higher than those of patients in the regular ward. Mean values of CRP were detected to be 6.28 ± 6.53 mg/dl in the regular ward cases and 16.9 ± 12.03 mg/dl in the ICU patients (p < 0.01). The stage of COPD did not indicate a significant difference in terms of CRP values. Mean CRP values were found to be 16.02 ± 6.95 mg/dl in mortal cases and 9.76 ± 11.09 mg/dl in survivors (p < 0.01). High CRP levels were considered as a prognostic parameter and indicator of severity of AE-COPD. Increased mortality risk was found to be associated with high CRP values.

C-reactive protein as a prognostic marker in chronic obstructive pulmonary disease

The present study aimed to evaluate whether circulating C-reactive protein (CRP) levels are a biomarker of systemic inflammation and a significant predictor of future chronic obstructive pulmonary disease (COPD) outcome. During the study, 116 patients with stable COPD and 35 age- and gender-matched healthy subjects with normal pulmonary function were observed. Patient follow-up was also performed to evaluate the strength of the associations between CRP levels and future outcomes. The observations from the present study showed that serum CRP levels were significantly higher in stable COPD patients than in control subjects (4.48±0.83 vs. 1.01±0.27 mg/l, respectively; P<0.05). In addition, it was identified that a serum CRP concentration of >3 mg/l is a poor prognostic variable of COPD compared with a CRP concentration of ≤3 mg/l [hazard ratio (HR), 2.71; 95% confidence interval (CI), 1.05–6.99; P<0.05]. A quantitative synthesis of four studies including 1,750 COPD patients was performed and statistically similar results were obtained (HR, 1.54; 95% CI, 1.14–2.07; P<0.01). The present study showed that circulating CRP levels are higher in stable COPD patients and, therefore, may be used as a long-term predictor of future outcomes. These observations highlight the importance of high sensitivity CRP assays in patients with stable COPD.

Utility of serum procalcitonin values in patients with acute exacerbations of chronic obstructive pulmonary disease: a cautionary note

BACKGROUND

Serum procalcitonin levels have been used as a biomarker of invasive bacterial infection and recently have been advocated to guide antibiotic therapy in patients with chronic obstructive pulmonary disease (COPD). However, rigorous studies correlating procalcitonin levels with microbiologic data are lacking. Acute exacerbations of COPD (AECOPD) have been linked to viral and bacterial infection as well as noninfectious causes. Therefore, we evaluated procalcitonin as a predictor of viral versus bacterial infection in patients hospitalized with AECOPD with and without evidence of pneumonia.

METHODS

Adults hospitalized during the winter with symptoms consistent with AECOPD underwent extensive testing for viral, bacterial, and atypical pathogens. Serum procalcitonin levels were measured on day 1 (admission), day 2, and at one month. Clinical and laboratory features of subjects with viral and bacterial diagnoses were compared.

RESULTS

In total, 224 subjects with COPD were admitted for 240 respiratory illnesses. Of these, 56 had pneumonia and 184 had AECOPD alone. A microbiologic diagnosis was made in 76 (56%) of 134 illnesses with reliable bacteriology (26 viral infection, 29 bacterial infection, and 21 mixed viral bacterial infection). Mean procalcitonin levels were significantly higher in patients with pneumonia compared with AECOPD. However, discrimination between viral and bacterial infection using a 0.25 ng/mL threshold for bacterial infection in patients with AECOPD was poor.

CONCLUSION

Procalcitonin is useful in COPD patients for alerting clinicians to invasive bacterial infections such as pneumonia but it does not distinguish bacterial from viral and noninfectious causes of AECOPD.

The importance of C-reactive protein and other inflammatory markers in patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a condition associated with inflammation in lungs and airways. The impacts of inflammatory process is not limited to respiratory system but extend to extrapulmonary organs with resultant complications involving endocrine, metabolic and cardiovascular systems. The extent and severity of inflammation may be partly estimated by serum measurement of several markers including serum CRP. Assessment of these markers can be useful not only for diagnostic or prognostic purpose but also for treatment evaluation of COPD patients. However, due to inconsistent results of published studies, at present the diagnostic or prognostic importance of inflammatory markers as well as their values in the evaluation of treatment outcome has not been accepted by all investigators. and so their routine applications require further studies. This review presents data in regard to the status of inflammatory markers at different stages of COPD patients and evaluates their predictive ability as well as their values in differential diagnosis or treatment evaluation.

Management of patients during and after exacerbations of chronic obstructive pulmonary disease: the role of primary care physicians

Current treatments have failed to stem the continuing rise in health care resource use and fatalities associated with exacerbations of chronic obstructive pulmonary disease (COPD). Reduction of severity and prevention of new exacerbations are therefore important in disease management, especially for patients with frequent exacerbations. Acute exacerbation treatment includes short-acting bronchodilators, systemic corticosteroids, and antibiotics if bacterial infections are present. Oxygen and/or ventilatory support may be necessary for life-threatening conditions. Rising health care costs have provided added impetus to find novel therapeutic approaches in the primary care setting to prevent and rapidly treat exacerbations before hospitalization is required. Proactive interventions may include risk reduction measures (eg, smoking cessation and vaccinations) to reduce triggers and supplemental pulmonary rehabilitation to prevent or delay exacerbation recurrence. Long-term treatment strategies should include individualized management, addressing coexisting nonpulmonary conditions, and the use of maintenance pharmacotherapies, eg, long-acting bronchodilators as monotherapy or in combination with inhaled corticosteroids to reduce exacerbations. Self-management plans that help patients recognize their symptoms and promptly access treatments have the potential to prevent exacerbations from reaching the stage that requires hospitalization.

Usefulness of consecutive biomarkers measurement in the management of community-acquired pneumonia

The aim of this study was to investigate whether procalcitonin (PCT), neopterin, C-reactive protein (CRP), and mid regional pro-atrial natriuretic peptide (MR-proANP) levels at admission and during the clinical course can be useful for the management of patients with pneumonia. The study population consisted of 75 patients with clinical and radiological diagnosis of pneumonia. Serum samples were collected at admission and during hospitalization. Complications were defined as intensive care unit (ICU) admission or death. The levels of PCT were significantly higher in pneumonia of definite bacterial origin in comparison to probable bacterial or unknown origin. The PCT levels were higher in pneumococcal pneumonia. The PCT and MR-proANP levels increased significantly according to the Pneumonia Severity Index (PSI). All biomarkers levels are higher in patients developing complications and who were dying. The serial levels of MR-proANP remain significantly elevated in patients developing complications and in patients classified in PSI and CURB-65 risk groups. In patients not developing complications, there is a significant decrease in the PCT levels. PCT can be useful for identifying pneumonia etiology. PCT and MR-proANP levels correlate with pneumonia severity rules. PCT and MR-proANP serial measurements can be useful for predicting short-term prognosis. Systemic biomarkers can provide additional information regarding clinical evolution, because these are dynamic and can be measured daily.