Copeptin predicts clinical deterioration and persistent instability in community-acquired pneumonia

The role of Copeptin in viral lower respiratory tract infections in child: A prospective case-control study

BACKGROUND

Lower respiratory tract infection (LRTI) is a leading cause of morbidity and mortality among children globally. Copeptin, released by the pituitary gland, serves as a biomarker for various conditions and, as a neuroendocrine stress hormone, is useful in acute conditions. This study aimed to determine the role of copeptin levels in LRTI in children and whether it can reliably predict pneumonia severity.

MATERIALS AND METHODS

This prospective case-control study was performed between April and October 2023. The study included four groups: (i) patients diagnosed with bronchiolitis (Group 1, n=25), (ii) patients diagnosed with mild to moderate pneumonia (Group 2, n=25), (iii) patients diagnosed with severe pneumonia (Group 3, n=25), and (iv) a control group (Group 4, n=26).

RESULTS

Copeptin values differed significantly between the groups (p<0.001 for all comparisons). Copeptin demonstrated a sensitivity of 87.4 % and specificity of 82.2 % for distinguishing between patients with bronchiolitis and pneumonia, using a cut-off value of >0.586 ng/ml. For the identification of patients with severe pneumonia versus those with mild to moderate pneumonia, copeptin exhibited a sensitivity of 97.9 % and specificity of 94.7 % with a cut-off value of >1.215 ng/ml. The copeptin level exhibited a positive correlation with fibrinogen and FAR levels while demonstrating a negative correlation with albumin levels (r=0.354, ⁎⁎P=0.002; r=0.408, ⁎⁎⁎P<0.001; and r=-0.334, ⁎⁎P=0.003, respectively).

CONCLUSIONS

Copeptin demonstrates potential as a predictor of disease severity in children with pneumonia. It can also serve as a valuable tool to guide physicians in differentiating between bronchiolitis and pneumonia, as well as in diagnosing severe pneumonia.

Risk factors and predicting nomogram for the clinical deterioration of non-severe community-acquired pneumonia

BACKGROUND

Currently, there remains insufficient focus on non-severe community-acquired pneumonia (CAP) patients who are at risk of clinical deterioration, and there is also a dearth of research on the related risk factors. Early recognition of hospitalized patients at risk of clinical deterioration will be beneficial for their clinical management.

METHOD

A retrospective study was conducted in The First Affiliated Hospital of Wenzhou Medical University, China, spanning from January 1, 2018 to April 30, 2022, and involving a total of 1,632 non-severe CAP patients. Based on whether their condition worsened within 72 h of admission, patients were divided into a clinical deterioration group and a non-clinical deterioration group. Additionally, all patients were randomly assigned to a training set containing 75% of patients and a validation set containing 25% of patients. In the training set, risk factors for clinical deterioration in patients with non-severe CAP were identified by using LASSO regression analysis and multivariate logistic regression analysis. A nomogram was developed based on identified risk factors. The effectiveness of the nomogram in both the training and validation sets was assessed using Receiver Operating Characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA).

RESULTS

Age, body mass index (BMI), body temperature, cardiovascular comorbidity, respiratory rate, LDH level, lymphocyte count and D-dimer level were identified as risk factors associated with the clinical deterioration of non-severe CAP within 72 h of admission. The area under curve (AUC) value of the nomogram was 0.78 (95% CI: 0.74-0.82) in the training set and 0.75 (95% CI: 0.67-0.83) in the validation set. Furthermore, the calibration curves for both the training and validation sets indicated that the predicted probability of clinical deterioration aligned with the actual probability. Additionally, DCA revealed clinical utility for the nomogram at a specific threshold probability.

CONCLUSION

The study successfully identified the risk factors linked to the clinical deterioration of non-severe CAP and constructed a nomogram for predicting the probability of deterioration. The nomogram demonstrated favorable predictive performance and has the potential to aid in the early identification and management of non-severe CAP patients at elevated risk of deterioration.

Copeptin: Up-to-date diagnostic and prognostic role highlight

Arginine Vasopressin (AVP) is one of the key hormones in the human body. AVP is clinically important because it maintains body fluid balance and vascular tone. Unfortunately, AVP laboratory measurements are always difficult and with low accuracy. Copeptin, the C-terminal of the AVP precursor, is released in equal amounts with AVP, making it a sensitive marker of AVP release. Despite being a non-specific biomarker, copeptin earned a lot of attention as a novel biomarker due to easy and quick laboratory measurements. Recent studies have reported the critical role of copeptin as a clinical indicator, especially in the diagnosis and prognosis of many diseases. Besides, it was reported that the combination between copeptin and gold standard biomarkers improved the prognostic values of those biomarkers. In this review, the role of copeptin as a new predictive diagnostic and prognostic biomarker of various diseases is highlighted according to the most recent studies. In addition, the importance of using copeptin as a marker in different medical departments and the impact of this on improving healthcare service was discussed.

Review novel insights into the diagnostic and prognostic function of copeptin in daily clinical practice

As is shown in previous reports, arginine vasopressin (AVP), as one of the most important hormones within circulation in human beings, is of great clinically significance given that it could maintain the body fluid balance and vascular tone. However, the laboratory measurements AVP in daily clinical practice are shown to be difficult and with low accuracy. Concerning on this notion, it is unpractical to use the serum levels of AVP in diagnosing multiple diseases. On the other hand, another key serum biomarker, copeptin, is confirmed as the C-terminal of the AVP precursor which could be released in equal amounts with AVP, resultantly making it as a sensitive marker of arginine vasopressin release. Notably, emerging recent evidence has demonstrated the critical function of copeptin as a clinical indicator, especially in the diagnosis and prognosis of several diseases in diverse organs, such as cardiovascular disease, kidney disease, and pulmonary disease. In addition, copeptin was recently verified to play an important role in diagnosing multiple acute diseases when combined it with other gold standard serum biomarkers, indicating that copeptin could be recognized as a vital disease marker. Herein, in the current review, the functions of copeptin as a new predictive diagnostic and prognostic biomarker of various diseases, according to the most recent studies, are well summarized. Furthermore, the importance of using copeptin as a serum biomarker in diverse medical departments and the impact of this on improving healthcare service is also summarized in the current review.

Association of Serum Albumin and Copeptin with Early Clinical Deterioration and Instability in Community-Acquired Pneumonia

Background: There is a paucity of data on biomarkers for the early deterioration and clinical instability of patients in community-acquired pneumonia (CAP), as treatment failure occurs in the first seven days in 90% of patients. Aim: To evaluate serum albumin and copeptin with CURB-65, PSI scoring and ATS/IDSA minor criteria for the prediction of early mortality or ICU-admission (7 days) and clinical instability after 72 h. Methods: In 100 consecutive hospitalized adult CAP patients, PSI-scores, CURB-65 scores, ATS/IDSA 2007 minor criteria, copeptin and albumin on admission were evaluated. Univariate and multivariate Cox regression analysis was performed to assess independent risk factors for early combined mortality or ICU admission. Predictive powers of albumin and copeptin were tested with ROC curves and ICU-free survival probability was tested using Kaplan−Meier analysis. Results: Albumin was lower and copeptin higher in patients with short-term adverse outcomes (p < 0.05). Cox regression analysis showed that albumin [HR (95% CI): 0.41 (0.18−0.94, p = 0.034)] and copeptin [HR (95% CI): 1.94 (1.03−3.67, p = 0.042)] were independent risk factors for early combined mortality or ICU admission (7 days). The Kaplan−Meier analysis observed that high copeptin (>27.12 ng/mL) and low albumin levels (<2.85 g/dL) had a lower (p < 0.001) survival probability. The diagnostic accuracy of albumin was better than copeptin. The inclusion of albumin and copeptin into ATS/IDSA minor criteria significantly improved their predictive power. Conclusions: Both biomarkers serum albumin and copeptin can predict early deterioration and clinical instability in hospitalized CAP patients and increase the prognostic power of the traditional clinical scoring systems.

Biomarkers Associated with Cardiovascular Disease in COVID-19

Coronavirus disease-19 (COVID-19) emerged late December 2019 in the city of Wuhan, China and has since spread rapidly all over the world causing a global pandemic. While the respiratory system is the primary target of disease manifestation, COVID-19 has been shown to also affect several other organs, making it a rather complex, multi-system disease. As such, cardiovascular involvement has been a topic of discussion since the beginning of the COVID-19 pandemic, primarily due to early reports of excessive myocardial injury in these patients. Treating physicians are faced with multiple challenges in the management and early triage of patients with COVID-19, as disease severity is highly variable ranging from an asymptomatic infection to critical cases rapidly deteriorating to intensive care treatment or even fatality. Laboratory biomarkers provide important prognostic information which can guide decision making in the emergency department, especially in patients with atypical presentations. Several cardiac biomarkers, most notably high-sensitive cardiac troponin (hs-cTn) and N-terminal pro-B-type natriuretic peptide (NT-proBNP), have emerged as valuable predictors of prognosis in patients with COVID-19. The purpose of this review was to offer a concise summary on prognostic cardiac biomarkers in COVID-19 and discuss whether routine measurements of these biomarkers are warranted upon hospital admission.

Copeptin in fluid disorders and stress

Copeptin, a glycosylated peptide of 39 amino acids, is the C-terminal segment of arginine vasopressin (AVP) precursor peptide, which is consisted of two other fragments, vasopressin and neurophysin Ⅱ. The main physiological functions of AVP are fluid and osmotic balance, cardiovascular homeostasis and regulation of the endocrine stress response. Numerous studies have demonstrated that the endogenous AVP in plasma is a meaningful biomarker to guide diagnosis and therapy of diseases associated with fluids disorders and stress. However, due to its instability, short half-time life in circulation and lack of readily available AVP assays, clinical measurement of AVP is restricted. In contrast to AVP, copeptin which is released in an equimolar mode with AVP from the pituitary, has emerged as a stable and simple-to-measure surrogate marker of AVP and displays excellent potential in diagnosis, differentiation and prognosis of various diseases. This review will discuss the studies on the clinical value of copeptin in different diseases, especially in AVP-dependent fluids disorders, as well as issues and prospects of the application of this potential biomarker.

Association between neutrophil to lymphocyte ratio and mortality among community acquired pneumonia patients: a meta-analysis

The neutrophil to lymphocyte ratio (NLR)is an emerging biomarker used in the prognosis of many conditions. We aimed to conduct a meta-analysis to assess the prognostic accuracy of the NLR in determining mortality in patients with Community acquired pneumonia (CAP). The Pubmed, EBSCO, and Scopus databases were searched to find all relevant articles. 10 articles with 5220 patients were included. The pooled area under the curve (AUC) of NLR admission levels to predict 30-Day mortality of CAP patients was 0.706; 95% CI (0.631 to 0.781), while the pooled AUC of NLR levels taken at 3-5 days was 0.882; 95% CI (0.818 to 0.945). Meta analysis also showed a significant difference in the NLR between the Survivors and 30-Day non-survivors. This difference was greater when NLR levels were taken at 3-5 days; Standardized mean difference (SMD) = 1.646; 95% CI (0.451 to 2.840) compared to NLR levels at admission SMD = 1.139; 95% CI (0.514 to 1.764). These results show that the NLR has potential to be incorporated in the routine assessment and stratification of CAP patients, especially in the early-stage evolution (3-5 days), keeping in mind the availability and cost effectiveness of this test.

Vasopressin and Breathing: Review of Evidence for Respiratory Effects of the Antidiuretic Hormone

Vasopressin (AVP) is a key neurohormone involved in the regulation of body functions. Due to its urine-concentrating effect in the kidneys, it is often referred to as antidiuretic hormone. Besides its antidiuretic renal effects, AVP is a potent neurohormone involved in the regulation of arterial blood pressure, sympathetic activity, baroreflex sensitivity, glucose homeostasis, release of glucocorticoids and catecholamines, stress response, anxiety, memory, and behavior. Vasopressin is synthesized in the paraventricular (PVN) and supraoptic nuclei (SON) of the hypothalamus and released into the circulation from the posterior lobe of the pituitary gland together with a C-terminal fragment of pro-vasopressin, known as copeptin. Additionally, vasopressinergic neurons project from the hypothalamus to the brainstem nuclei. Increased release of AVP into the circulation and elevated levels of its surrogate marker copeptin are found in pulmonary diseases, arterial hypertension, heart failure, obstructive sleep apnoea, severe infections, COVID-19 due to SARS-CoV-2 infection, and brain injuries. All these conditions are usually accompanied by respiratory disturbances. The main stimuli that trigger AVP release include hyperosmolality, hypovolemia, hypotension, hypoxia, hypoglycemia, strenuous exercise, and angiotensin II (Ang II) and the same stimuli are known to affect pulmonary ventilation. In this light, we hypothesize that increased AVP release and changes in ventilation are not coincidental, but that the neurohormone contributes to the regulation of the respiratory system by fine-tuning of breathing in order to restore homeostasis. We discuss evidence in support of this presumption. Specifically, vasopressinergic neurons innervate the brainstem nuclei involved in the control of respiration. Moreover, vasopressin V1a receptors (V1aRs) are expressed on neurons in the respiratory centers of the brainstem, in the circumventricular organs (CVOs) that lack a blood-brain barrier, and on the chemosensitive type I cells in the carotid bodies. Finally, peripheral and central administrations of AVP or antagonists of V1aRs increase/decrease phrenic nerve activity and pulmonary ventilation in a site-specific manner. Altogether, the findings discussed in this review strongly argue for the hypothesis that vasopressin affects ventilation both as a blood-borne neurohormone and as a neurotransmitter within the central nervous system.

Improvement of outcome prediction of hospitalized patients with COVID-19 by a dual marker strategy using high-sensitive cardiac troponin I and copeptin

Background

COVID-19 has been associated with a high prevalence of myocardial injury and increased cardiovascular morbidity. Copeptin, a marker of vasopressin release, has been previously established as a risk marker in both infectious and cardiovascular disease.

Methods

This prospective, observational study of patients with laboratory-confirmed COVID-19 infection was conducted from June 6th to November 26th, 2020 in a tertiary care hospital. Copeptin and high-sensitive cardiac troponin I (hs-cTnI) levels on admission were collected and tested for their association with the primary composite endpoint of ICU admission or 28-day mortality.

Results

A total of 213 eligible patients with COVID-19 were included of whom 55 (25.8%) reached the primary endpoint. Median levels of copeptin and hs-cTnI at admission were significantly higher in patients with an adverse outcome (Copeptin 29.6 pmol/L, [IQR, 16.2–77.8] vs 17.2 pmol/L [IQR, 7.4–41.0] and hs-cTnI 22.8 ng/L [IQR, 11.5–97.5] vs 10.2 ng/L [5.5–23.1], P < 0.001 respectively). ROC analysis demonstrated an optimal cut-off of 19.3 pmol/L for copeptin and 16.8 ng/L for hs-cTnI and an increase of either biomarker was significantly associated with the primary endpoint. The combination of raised hs-cTnI and copeptin yielded a superior prognostic value to individual measurement of biomarkers and was a strong prognostic marker upon multivariable logistic regression analysis (OR 4.274 [95% CI, 1.995–9.154], P < 0.001). Addition of copeptin and hs-cTnI to established risk models improved C-statistics and net reclassification indices.

Conclusion

The combination of raised copeptin and hs-cTnI upon admission is an independent predictor of ICU admission or 28-day mortality in hospitalized patients with COVID-19.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00392-021-01970-4.

Can copeptin predict the severity of coronavirus disease 2019 infection?

OBJETIVE

Coronavirus disease 2019 (COVID-19) has quickly turned into a health problem globally. Early and effective predictors of disease severity are needed to improve the management of the patients affected with COVID-19. Copeptin, a 39-amino acid glycopeptide, is known as a C-terminal unit of the precursor pre-provasopressin (pre-proAVP). Activation of AVP system stimulates copeptin secretion in equimolar amounts with AVP. This study aimed to determine serum copeptin levels in the patients with COVID-19 and to examine the relationship between serum copeptin levels and the severity of the disease.

METHODS

The study included 90 patients with COVID-19. The patients with COVID-19 were divided into two groups according to disease severity as mild/moderate disease (n=35) and severe disease (n=55). All basic demographic and clinical data of the patients were recorded and blood samples were collected.

RESULTS

Copeptin levels were significantly higher in the patients with severe COVID-19 compared with the patients with mild/moderate COVID-19 (p<0.001). Copeptin levels were correlated with ferritin and fibrinogen levels positively (r=0.32, p=0.002 and r=0.25, p=0.019, respectively), and correlated with oxygen saturation negatively (r=-0.37, p<0.001). In the multivariate logistic regression analysis, it was revealed that copeptin (OR: 2.647, 95%CI 1.272-5.510; p=0.009) was an independent predictor of severe COVID-19 disease. A cutoff value of 7.84 ng/mL for copeptin predicted severe COVID-19 with a sensitivity of 78% and a specificity of 80% (AUC: 0.869, 95%CI 0.797-0.940; p<0.001).

CONCLUSION

Copeptin could be used as a favorable prognostic biomarker while determining the disease severity in COVID-19.

Neutrophil-Dependent Immunity During Pulmonary Infections and Inflammations

Rapid recruitment of neutrophils to an inflamed site is one of the hallmarks of an effective host defense mechanism. The main pathway through which this happens is by the innate immune response. Neutrophils, which play an important part in innate immune defense, migrate into lungs through the modulation actions of chemokines to execute a variety of pro-inflammatory functions. Despite the importance of chemokines in host immunity, little has been discussed on their roles in host immunity. A holistic understanding of neutrophil recruitment, pattern recognition pathways, the roles of chemokines and the pathophysiological roles of neutrophils in host immunity may allow for new approaches in the treatment of infectious and inflammatory disease of the lung. Herein, this review aims at highlighting some of the developments in lung neutrophil-immunity by focusing on the functions and roles of CXC/CC chemokines and pattern recognition receptors in neutrophil immunity during pulmonary inflammations. The pathophysiological roles of neutrophils in COVID-19 and thromboembolism have also been summarized. We finally summarized various neutrophil biomarkers that can be utilized as prognostic molecules in pulmonary inflammations and discussed various neutrophil-targeted therapies for neutrophil-driven pulmonary inflammatory diseases.

Investigation of the plasma copeptin level in cases with childhood migraine

Copeptin is a hypothalamic stress hormone that is synthesized in the hypothalamus together with Arginine-vasopressin and circulated from the neurohypophysis in equimolar amounts and can indicate the individual stress level. The aim of this study was to investigate the plasma copeptin level for childhood migraine headache. In this study, total oxidant status (TOS); total antioxidant status (TAS); oxidative stress index (OSI); and copeptin were measured in the plasma samples of 61 migraine patients and 60 matched healthy participants. The median plasma copeptin levels in the patients group and control group were 298.25 and 194.35 pg/mL, respectively. Copeptin levels were significantly higher in migraine patients than in the healthy control group. The specificity and sensitivity of copeptin for 249.5 pg/dL cut off value predicting diagnosis of migraine were 67% and 64%, respectively. In addition, TOS and OSI levels were found to be higher and TAS levels were significantly lower in patients with migraine than healthy controls. Plasma copeptin levels are thought to increase in cases of childhood migraine secondary to increased oxidative stress. In the diagnosis of childhood migraine cases, it can be used together with oxidative stress biomarkers such as TAS, TOS and OSI as a complementary parameter.

Biomarkers in Community-Acquired Pneumonia (Cardiac and Non-Cardiac)

Community-acquired pneumonia (CAP) remains the first cause of morbidity and mortality worldwide due to infection. Several aspects such as severity and host response are related to its clinical course and outcome. Beyond the acute implications that the infection provokes in the host, pneumonia also has long-term negative consequences. Among them, cardiovascular complications and mortality are the most outstanding. Therefore, an adequate recognition and stratification of the risk of complications and mortality is crucial. Many biomarkers have been studied for these reasons, considering that each biomarker mirrors a different aspect. Moreover, the clinical application of many of them is still being deliberated because of their limitations and the heterogeneity of the disease. In this review, we examine some of the most relevant biomarkers that we have classified as cardiac and non-cardiac. We discuss some classic biomarkers and others that are considered novel biomarkers, which are mainly involved in cardiovascular risk.

The relationship among plasma copeptin, carboxyhemoglobin, and lactate levels in carbon monoxide poisoning

OBJECTIVE

The aim of our study is to determine whether there is a change in the plasma levels of copeptin and there is a relationship among the plasma levels of carboxyhemoglobin (COHb), lactate, and copeptin levels in patients presenting to the emergency department with carbon monoxide (CO) poisoning.

METHODS

Fifty-seven patients admitted to the emergency department with CO poisoning were included in the study. The blood samples of the patients were collected on arrival 0th, 6th, and 12th hours for copeptin, lactate, and COHb levels. Data were analyzed using SPSS-17 statistical software.

RESULTS

Arrival serum copeptin levels of the patients were compared to copeptin levels of healthy individuals and a statistically significant difference was found between them (p = 0.008). There was a statistically significant difference between the arrival levels of copeptin and 6th-hour (p = 0.006) and 12th-hour (p = 0.001) levels of copeptin. There was no significant difference between 6th-hour and 12th-hour copeptin levels (p = 0.51). In terms of serum lactate levels, there was a significant difference between arrival and 6th h (p < 0.001), arrival and 12th h (p < 0.001), and 6th and 12th h (p < 0.001). Likewise, in terms of serum COHb levels, there was a significant difference between arrival and 6th h (p < 0.001), arrival and 12th h (p < 0.001), and 6th and 12th h (p < 0.001). There was a positive correlation between COHb and lactate levels on arrival (r = 0.52; p = 0.001).

CONCLUSION

Copeptin as a stress hormone can be used in the diagnosis and monitoring of patients with CO poisoning. However, the copeptin level was not superior to COHb and lactate levels.

Evaluation of Copeptin during Pulmonary Exacerbation in Cystic Fibrosis

Copeptin was found to be a stable biomarker of inflammation and stress response in cardiac, renal, metabolic, and respiratory conditions such as pneumonia. The aim of this study was to investigate the copeptin levels in biological fluids (serum and sputum supernatant) of cystic fibrosis pediatric patients during pulmonary exacerbation and remission and to investigate the possible influence of copeptin levels on disease severity and quality of life. Copeptin serum concentrations were measured in 28 pediatric cystic fibrosis (CF) patients: 13 in stable condition and 15 during pulmonary exacerbation. In 10 CF patients, copeptin was also measured in the sputum. In all the patients, we assessed complete blood count, BMI, sputum culture, lung function, and chest imaging (with Brasfield score). The severity of symptoms was assessed using the Shwachman-Kulczycki (SK) score, and the quality of life was assessed with the Cystic Fibrosis Quality of Life Questionnaire-Revised (CFQ-R). Copeptin concentrations in serum and sputum supernatant was measured using an ELISA kit. Statistical analysis was done in Statistica v.12. Serum and sputum copeptin levels were higher in CF patients during pulmonary exacerbation than in a stable period, but the differences were not significant (p = 0.58 and p = 0.13, respectively). Copeptin did not correlate significantly with any clinical, laboratory, or spirometry markers of exacerbation. There was, however, a significant inverse correlation between the serum copeptin level and symptoms severity (r = ‐0.77, p = 0.008) and radiological changes (r = ‐0.5626, p = 0.036) during pulmonary exacerbation in pediatric CF patients. Copeptin also inversely correlated with the quality of life domains in CF patients: vitality and eating habits, mostly loss of appetite (p = 0.031 and p = 0.016, respectively). Copeptin may be useful to identify patients with a higher risk of deterioration to improve their outcomes.

Exercise upregulates copeptin levels which is not regulated by interleukin-1

Objective

Studies have suggested that arginine vasopressin (AVP) and its surrogate marker copeptin increase during exercise, independently of serum sodium and/or osmolality. In extreme cases, this can lead to runners-induced hyponatremia. Interleukin-1 (IL-1) increases during exercise and induces AVP in animal models. We here therefore investigate whether copeptin (a surrogate marker for AVP) increases upon exercise in young and healthy males, and whether this increase is regulated by IL-1.

Design

In a randomized, placebo-controlled, double-blind, crossover trial in 17 healthy male volunteers, the effect of the IL-1 receptor antagonist anakinra on exercise-induced copeptin was compared with placebo.

Methods

Participants exercised for one hour at 75% of VO_2max and were not allowed to drink/eat 6 hours before and during the study. Participants received either 100 mg of anakinra or placebo 1h before exercise. Blood was drawn at certain time intervals.

Results

In both groups, copeptin levels were induced by 2.5-fold upon exercise (p<0.001), from 4.5–10.6 pmol/l in the placebo, and 4.3–11.3 pmol/l in the anakinra group, (p = 0.38). One hour after exercise, copeptin levels dropped to 7.7 and 7.9 pmol/l in the placebo and anakinra group, respectively (p = 0.58). The increase of copeptin levels was not explained by sodium concentrations.

Conclusions

Exercise induces a continuous rise of plasma copeptin levels in healthy male volunteers independently of sodium levels and fluid intake. This increase is not regulated by the IL-1 pathway.

Neutrophil Count Percentage and Neutrophil-Lymphocyte Ratio as Prognostic Markers in Patients Hospitalized for Community-Acquired Pneumonia

INTRODUCTION

Community-acquired pneumonia (CAP) is a common serious infection. This study aimed to evaluate the prognostic utility of neutrophil count percentage (NCP) and neutrophil-lymphocyte ratio (NLR) in patients with CAP.

METHODS

Retrospective study of hospitalized patients with CAP. Patients had a blood test at admission and 3-5 days after hospitalization (early-stage test). The main outcome variables were 30-day and 90-day mortality.

RESULTS

Two hundred and 9patients were included. Patients who survived had significant reductions in both NCP and NLR between admission and the day 3-5 blood tests (from 85.8% to 65.4% for NCP and from 10.1 to 3.2 for NLR). Twenty-five patients died in the first 90 days. Patients who died had lower, non-significant reductions in NCP (from 84.8% to 74%) and NLR (from 9.9 to 6.9) and significantly higher early-stage NCP and NLR than those who survived. NCP values higher than 85% and NLR values higher than 10 in the early-stage blood test were associated with a higher risk of mortality, even after multivariate adjustment (HR for NCP: 12; HR for NLR: 6.5).

CONCLUSION

NCP and NLR are simple, low-cost parameters with prognostic utility, especially when measured 3-5 days after CAP diagnosis. High NLR and/or NCP levels are associated with a greater risk of mortality at 90 days.

Release and Decay Kinetics of Copeptin vs AVP in Response to Osmotic Alterations in Healthy Volunteers

CONTEXT

Copeptin is the C-terminal fragment of the arginine vasopressin (AVP) prohormone whose measurement is more robust than that of AVP. Similar release and clearance characteristics have been suggested promoting copeptin as a surrogate marker.

OBJECTIVE

To characterize the physiology of osmotically regulated copeptin release and its half-life in direct comparison with plasma AVP.

DESIGN

Ninety-one healthy volunteers underwent a standardized three-phase test protocol including (1) osmotic stimulation into the hypertonic range by hypertonic-saline infusion followed by osmotic suppression via (2) oral water load and (3) subsequent glucose infusion. Plasma copeptin, AVP, serum sodium, and osmolality levels were measured in regular intervals.

RESULTS

In phase 1, an increase in median osmotic pressure [289 (286; 291) to 311 (309; 314) mOsm/kg H2O] caused similar release kinetics of plasma copeptin [4 (3.1; 6) to 29.3 (18.6; 48.2) pmol/L] and AVP [1 (0.7; 1.6) to 10.3 (6.8; 18.8) pg/mL]. Subsequent osmotic suppression to 298 (295; 301) mOsm/kg at the end of phase 3 revealed markedly different decay kinetics between both peptides-an estimated initial half-life of copeptin being approximately 2 times longer than that of AVP (26 vs 12 minutes).

CONCLUSION

Copeptin is released in equimolar amounts with AVP in response to osmotic stimulation, suggesting its high potential as an AVP surrogate for differentiation of osmotic disorders. Furthermore, we here describe the decay kinetics of copeptin in response to osmotic depression enabling to identify a half-life for copeptin in direct comparison with AVP.

Predictors of treatment failure and clinical stability in patients with community acquired pneumonia

Community acquired pneumonia (CAP) is the leading infectious cause of mortality worldwide with approximately 10% of patients hospitalized requiring intensive care unit (ICU) admission. The ability to predict clinical stability (CS) and treatment failure (TF) enables the clinician to alter antibiotics appropriately, facilitate a timely ICU admission, or arrange a suitable discharge. The detection of CS and TF can be difficult and changes in clinical signs may be subtle or delayed. Thus clinical scores and biomarkers are routinely used to identify severity and monitor clinical progression. The evidence, however, is vast and the definitive role of these systems is at times difficult to elucidate. The aim of this review is to analyse the current literature and to provide a rational and clinically focused view of the predictive utility of various systems used to identify CS and TF in CAP.

An update on the pharmacotherapeutic management of lower respiratory tract infections

INTRODUCTION

Our knowledge about lower respiratory tract infections (LRTIs) has improved substantially in the last years, but the management of respiratory infections is still a challenge and we are still far from using precision medicine in their treatment. Areas covered: The approaches developed in recent years to improve the pharmacotherapeutic management of LRTIs, such as novel diagnostic assays to facilitate medical decision-making, attempts for selecting an optimal empiric antibiotic regimen, and the role of new and possibly unproven adjunctive therapies, are described. Expert opinion: Early and appropriate antibiotics remain the cornerstone in the treatment of LRTIs. The updated trend is to apply antimicrobial stewardship principles and initiatives to optimize both the management and the outcomes of LTRIs. Biomarkers, mainly C-reactive protein (CRP) and procalcitonin (PCT), can improve the diagnostic and prognostic assessment of LRTIs and aid to guide antibiotic therapy. The widespread use of antimicrobial agents has greatly contributed to faster development of antibiotic resistance and the emergence of opportunistic pathogens, which substitute the indigenous microbiota. However, very few new antibiotics in development to overcome existing resistance and ensure continued success in the treatment of LRTIs have been approved, likely because antibiotic stewardship programs discourage the use of new agents.

Inflammation biomarkers in blood as mortality predictors in community-acquired pneumonia admitted patients: Importance of comparison with neutrophil count percentage or neutrophil-lymphocyte ratio

Introduction

The increase and persistence of inflammation in community-acquired pneumonia (CAP) patients can lead to higher mortality. Biomarkers capable of measuring this inadequate inflammatory response are likely candidates to be related with a bad outcome. We investigated the association between concentrations of several inflammatory markers and mortality of CAP patients.

Material and methods

This was a prospective study of hospitalised CAP patients in a Spanish university hospital. Blood tests upon admittance and in the early-stage evolution (72–120 hours) were carried out, where C-reactive protein, procalcitonin, proadrenomedullin, copeptin, white blood cell, Lymphocyte Count Percentage (LCP), Neutrophil Count Percentage (NCP) and Neutrophil/Lymphocyte Ratio (NLR) were measured. The outcome variable was mortality at 30 and 90 days. Statistical analysis included logistic regression, ROC analysis and area-under-curve test.

Results

154 hospitalised CAP patients were included. Patients who died during follow-up had higher levels of procalcitonin, copeptin, proadrenomedullin, lower levels of LCP, and higher of NCP and NLR. Remarkably, multivariate analysis showed a relationship between NCP and mortality, regardless of age, severity of CAP and comorbidities. AUC analysis showed that NLR and NCP at admittance and during early-stage evolution achieved a good diagnostic power. ROC test for NCP and NLR were similar to those of the novel serum biomarkers analysed.

Conclusions

NLR and NCP, are promising candidate predictors of mortality for hospitalised CAP patients, and both are cheaper, easier to perform, and at least as reliable as the new serum biomarkers. Future implementation of new biomarkers would require comparison not only with classic inflammatory parameters like White Blood Cell count but also with NLR and NCP.

Tools for outcome prediction in patients with community acquired pneumonia

INTRODUCTION

Community-acquired pneumonia (CAP) is one of the most common causes of mortality world-wide. The mortality rate of patients with CAP is influenced by the severity of the disease, treatment failure and the requirement for hospitalization and/or intensive care unit (ICU) management, all of which may be predicted by biomarkers and clinical scoring systems. Areas covered: We review the recent literature examining the efficacy of established and newly-developed clinical scores, biological and inflammatory markers such as C-Reactive protein (CRP), procalcitonin (PCT) and Interleukin-6 (IL-6), whether used alone or in conjunction with clinical severity scores to assess the severity of CAP, predict treatment failure, guide acute in-hospital or ICU admission and predict mortality. Expert commentary: The early prediction of treatment failure using clinical scores and biomarkers plays a developing role in improving survival of patients with CAP by identifying high-risk patients requiring hospitalization or ICU admission; and may enable more efficient allocation of resources. However, it is likely that combinations of scoring systems and biomarkers will be of greater use than individual markers. Further larger studies are needed to corroborate the additive value of these markers to clinical prediction scores to provide a safer and more effective assessment tool for clinicians.

Prognostic value of mid-regional pro-adrenomedullin (MR-proADM) in patients with community-acquired pneumonia: a systematic review and meta-analysis

Background

The early identification of patients at risk of dying from community-acquired pneumonia (CAP) is critical for their treatment and for defining hospital resource consumption. Mid-regional pro-adrenomedullin (MR-proADM) has been extensively investigated for its prognostic value in CAP. However, the results are conflicting. The purpose of the present meta-analysis was to explore the diagnostic accuracy of MR-proADM for predicting mortality in patients suffering from CAP, particularly emergency department (ED) patients.

Method

We systematically searched the PubMed, Embase, Web of Knowledge and Cochrane databases. Studies were included if a 2 × 2 contingency table could be constructed based on both the MR-proADM level and the complications or mortality of patients diagnosed with CAP. The prognostic accuracy of MR-proADM in CAP was assessed using the bivariate meta-analysis model. We used the Q-test and I² index to evaluate heterogeneity.

Results

MR-proADM displayed moderate diagnostic accuracy for predicting complications in CAP, with an overall area under the SROC curve (AUC) of 0.74 (95 % CI: 0.70–0.78). Eight studies with a total of 4119 patients in the emergency department (ED) were included. An elevated MR-proADM level was associated with increased risk of death from CAP (RR 6.16, 95 % CI 4.71–8.06); the I² value was 0.0 %, and a fixed-effects model was used to pool RR. The pooled sensitivity and specificity were 0.74 (95 % CI: 0.67–0.79) and 0.73 (95 % CI: 0.70–0.77), respectively. The positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were 2.8 (95 % CI, 2.3–3.3) and 0.36 (95 % CI, 0.29–0.45), respectively. In addition, the diagnostic odds ratio (DOR) was 8 (95 % CI, 5–11), and the overall area under the SROC curve was 0.76 (95 % CI, 0.72–0.80).

Conclusions

Our study has demonstrated that MR-proADM is predictive of increased complications and higher mortality rates in patients suffering from CAP. Future studies are warranted to determine the prognostic accuracy of MR-proADM in conjunction with severity scores or other biomarkers and to determine an optimal cut-off level.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1566-3) contains supplementary material, which is available to authorized users.

A Dormant Microbial Component in the Development of Preeclampsia

Preeclampsia (PE) is a complex, multisystem disorder that remains a leading cause of morbidity and mortality in pregnancy. Four main classes of dysregulation accompany PE and are widely considered to contribute to its severity. These are abnormal trophoblast invasion of the placenta, anti-angiogenic responses, oxidative stress, and inflammation. What is lacking, however, is an explanation of how these themselves are caused. We here develop the unifying idea, and the considerable evidence for it, that the originating cause of PE (and of the four classes of dysregulation) is, in fact, microbial infection, that most such microbes are dormant and hence resist detection by conventional (replication-dependent) microbiology, and that by occasional resuscitation and growth it is they that are responsible for all the observable sequelae, including the continuing, chronic inflammation. In particular, bacterial products such as lipopolysaccharide (LPS), also known as endotoxin, are well known as highly inflammagenic and stimulate an innate (and possibly trained) immune response that exacerbates the inflammation further. The known need of microbes for free iron can explain the iron dysregulation that accompanies PE. We describe the main routes of infection (gut, oral, and urinary tract infection) and the regularly observed presence of microbes in placental and other tissues in PE. Every known proteomic biomarker of "preeclampsia" that we assessed has, in fact, also been shown to be raised in response to infection. An infectious component to PE fulfills the Bradford Hill criteria for ascribing a disease to an environmental cause and suggests a number of treatments, some of which have, in fact, been shown to be successful. PE was classically referred to as endotoxemia or toxemia of pregnancy, and it is ironic that it seems that LPS and other microbial endotoxins really are involved. Overall, the recognition of an infectious component in the etiology of PE mirrors that for ulcers and other diseases that were previously considered to lack one.

Copeptin: Pathophysiology and potential clinical impact

Copeptin, a C-terminal part of the precursor pre-provasopressin is a novel biomarker of arginine-vasopressin (AVP) system. Measurements of AVP concentration are not used in clinical practice because of technical difficulties. Copeptin is synthesized in stoichiometric ratio with AVP, hence it reflects vasopressin concentration in human plasma and serum. This review outlines current research concerning the role of copeptin as a prognostic marker in different diseases and its potential clinical value.

Midregional proadrenomedullin for prognosis in community-acquired pneumonia: a systematic review

INTRODUCTION

The initial prognostic assessment of patients with community-acquired pneumonia( CAP) has important clinical implications. We hypothesized that midregional proadrenomedullin(MR-proADM) is a valuable test for the prediction of outcomes in patients with CAP.Methods: We performed a systemic review of the literature and a meta-analysis to evaluate the prognostic value of MR-proADM for short and long-term mortality in patients with CAP.Results: Twelve studies were included in the systematic review. Elevated MR-proADM was associated with an increase in short-term mortality (OR Z 6.8; 95% CI: 4.65-10.13; P value < 0.001) and complications (OR = 5.0; 95% CI: 3.86-6.49; P value < 0.001). The pooled analysis of 4 studies showed an improvement in the discriminant ability by 8% (95% CI: 2%e14%)when MR-proADM was added to CURB-65/CRB-65. Studies that reported long-term prognosis indicated an increased risk of death in patients with elevated MR-proADM.Conclusion: Elevated level of MR-proADM is significantly associated with both short-term mortality and complications in patients with CAP. Studies also indicate that MR-proADM has prognostic value for prediction of long-term mortality in these patients. The addition of MR-proADM improves the discriminant ability of CURB-65/CRB-65.

Laboratory markers predicting severity of acute pancreatitis

Acute pancreatitis (AP) is an inflammatory disease of highly variable severity, ranging from mild cases with low mortality to severe cases with high mortality. Numerous biomarkers have been studied as potential early predictors of the severity of this disease so that treatment can be optimally tailored to prevent complications. We aim to present and discuss the most relevant biomarkers for early severity assessment in AP that have been studied to date. We review the current literature on biomarkers that have been used to predict the severity in AP. C-reactive protein (CRP) is still considered to be the gold standard, with a cut-off value of 150 mg/ml 48 h after disease onset. Other markers, including procalcitonin (PCT) and interleukin 6 (IL-6) have been implemented in some hospitals, but are not used on a routine basis. Most other markers, including acute phase proteins (LBP, SAA, PTX3), cytokines (Il-8, TNF-a, MIF), activation peptides of pancreatic proteases (TAP, CAPAP, PLAP), antiproteases (AAT, a2M), adhesion molecules (ICAM-1, selectins, E-cadherin) and leukocyte-derived enzymes (PA2, PMN-E) have shown some promising results but have not been routinely implemented. Furthermore, new and interesting biomarkers (Copeptin, TRX-1, Ang-2, E-2) have shown good results, but more research is needed to determine if they could play a role in the future. Various reasons why new markers for disease severity have not been adopted in daily routine include low accuracy, cumbersome laboratory techniques and high cost. Despite these difficulties, research is still very active in finding new markers to predict the severity of AP.

Copeptin testing in acute myocardial infarction: ready for routine use?

Suspected acute myocardial infarction is one of the leading causes of admission to emergency departments. In the last decade, biomarkers revolutionized the management of patients with suspected acute coronary syndromes. Besides their pivotal assistance in timely diagnosis, biomarkers provide additional information for risk stratification. Cardiac troponins I and T are the most sensitive and specific markers of acute myocardial injury. Nonetheless, in order to overcome the remaining limitations of these markers, novel candidate biomarkers sensitive to early stage of disease are being extensively investigated. Among them, copeptin, a stable peptide derived from the precursor of vasopressin, emerged as a promising biomarker for the evaluation of suspected acute myocardial infarction. In this review, we summarize the currently available evidence for the usefulness of copeptin in the diagnosis and risk stratification of patients with suspected acute myocardial infarction in comparison with routine biomarkers.

Correlations between extent of X-ray infiltration and levels of serum C-reactive protein in adult non-severe community-acquired pneumonia

Pneumonia cases can vary in both severity and chest X-ray findings. Elevated C-reactive protein (CRP) levels may be an indicator of disease severity. We retrospectively evaluated factors correlated with the extent of chest X-ray infiltration both in community-acquired pneumonia (CAP) and a subgroup of cases with pneumococcal pneumonia. In a clinical study that evaluated the efficacy of sitafloxacin, 137 patients with CAP had been previously enrolled. In our study, 75 patients with pneumococcal pneumonia were identified among these 137 CAP patients. The extent of chest X-ray infiltration was scored and correlations with age, sex, body temperature, white blood cell (WBC) count, and CRP levels were analyzed using multivariate analysis with logistic regression. Significant correlations were observed between the extent of chest X-ray infiltration and CRP levels in both CAP and pneumococcal pneumonia. Our data indicates that CRP is a valuable and informative resource that could reflect the severity of pneumonia in cases of both CAP and pneumococcal pneumonia.

Prediction of prognosis by markers in community-acquired pneumonia

Early identification of patients with community-acquired pneumonia (CAP) at risk of poor outcome is critical for defining site of care and may impact on hospital resource consumption and prognosis. The Pneumonia Severity Index and CURB-65 are clinical rules that accurately identify individuals at risk of death. However, these scores have some limitations. Therefore in recent years, increasing attention has been being paid to research on biomarkers, since they have the potential to resolve fundamental issues regarding prognostic prediction that cannot be readily addressed using CAP-specific scores. Nevertheless, the use of biomarkers in this context needs to be validated in prospective trials so as to elucidate how they can best be applied in practice. This review examines the usefulness of biomarkers, whether used alone or in conjunction with other clinical severity of illness scores, for identifying CAP patients at risk of short- and long-term mortality and for predicting both the need for intensive care unit admission and the potential for treatment failure.

Diagnostic performance of copeptin in patients with acute nontraumatic chest pain: BWH-TIMI ED chest pain study

BACKGROUND

Arginine-vasopressin (AVP) is an acute marker of physiologic stress. Copeptin is the C-terminal fragment of vasopressin precursor hormone that is more easily measured than AVP. Studies assessing the utility of copeptin in the diagnosis of myocardial infarction (MI) have demonstrated mixed results.

HYPOTHESIS

The aim of this study was to test the hypothesis that copeptin improves diagnostic performance when added to troponin for detecting MI in patients presenting to the emergency department with nontraumatic chest pain.

METHODS

We measured copeptin, local cardiac troponin I (local cTnI), and a contemporary sensitive cardiac troponin I (sensitive cTnI) at presentation and serially in patients who presented with acute chest pain. A copeptin cutoff of 14 pmol/L was utilized.

RESULTS

MI was diagnosed in 25.7% of patients. Noncoronary acute cardiopulmonary causes of chest pain occurred in 12.8%. Patients with MI had significantly higher copeptin levels than patients with noncardiac chest pain (P < 0.001). The area under the receiver operating characteristic curve (AUC) for copeptin was 0.60 (95% confidence interval: 0.54-0.66), significantly less than the AUC for local cTnI (0.92) or sensitive cTnI (0.96). The combination of copeptin with either the local or sensitive troponin assay (c-statistics 0.92 and 0.95, respectively) did not significantly improve the AUC as compared to either troponin assay alone. This finding persisted in the subgroup of early presenters (≤ 6 hours from symptom onset).

CONCLUSIONS

Copeptin did not improve the diagnostic performance for detecting MI when used alone or in combination with a contemporary sensitive cTnI assay, though our cohort had relatively few early presenters.

Plasma copeptin levels are associated with prognosis of severe acute pancreatitis

Copeptin reflects the individual stress level, and is correlated with outcomes of critical illness. This study was designed to evaluate its relationship with disease severity, local complications, organ failure and mortality of severe acute pancreatitis (SAP). Seventy-eight SAP patients and 78 sex- and age-matched healthy individuals were recruited. Plasma samples were obtained on admission from SAP patients and at study entry from healthy individuals. Copeptin concentration was determined using enzyme-linked immunosorbent assay. Plasma copeptin level was obviously higher in patients than in healthy individuals, was identified as an independent predictor of local complications, organ failure and in-hospital mortality, was highly associated with traditional predictors of disease severity and mortality including the Acute Physiology and Chronic Health Care Evaluation II score, Ranson score, multiple organ dysfunction score, sequential organ failure assessment score, and predicted local complications, organ failure, and in-hospital mortality of SAP patients with high areas under receiver operating characteristic curve. Furthermore, its predictive value was similar to the traditional predictors'. However, it could not improve these traditional predictors' predictive values. Therefore, increased plasma copeptin level is associated with disease severity and identified as a novel prognostic marker of local complications, organ failure and mortality after SAP.

Effects of acute exercise and xanthine oxidase inhibition on novel cardiovascular biomarkers

Several sports have been associated with a postexercise increase of cardiac, liver, and skeletal muscle biomarkers of injury. Exhaustive or acute physical exercise causes an increased generation of reactive oxygen species, resulting in cellular injury. Thus, exercise and training may trigger pathophysiological changes in serum concentrations of a variety of biomarkers. In this study, we aimed to evaluate the variation of novel biomarkers of stress and cardiovascular disease such as copeptin, midregional part of proadrenomedullin (MR-proADM), growth differentiation factor 15 (GDF15), soluble vascular endothelial growth factor receptor, and placental growth factor along with uric acid before and after acute high-intensity exercise and allopurinol administration. We also assessed whether allopurinol administration may affect the circulating levels of these biomarkers by inhibition of XO activity. This is a double-blind, placebo-controlled study in which 12 professional football players were divided into 2 experimental groups. An oral dose of 300 mg of allopurinol was administered to one group of six participants 4 hours before a match of the Spanish Football League, whereas the other 6 participants received placebo (cellulose). Venous blood samples were obtained before the match (baseline) and twelve hours afterwards (post-match). Serum MR-proADM levels increased significantly in the placebo group, whereas serum GDF15 levels increased significantly in both the placebo and allopurinol group after the match. No differences in the other parameters tested were found after the match in any experimental group. The trend toward postexercise increase of serum MR-proADM and GDF15 levels shows that the metabolism of these proteins is clearly imbalanced after exercise, which thereby represents a potential source of biological variability in their clinical assessment.

Relationship between plasma copeptin levels and complications of community-acquired pneumonia in preschool children

High plasma copeptin level has been associated with clinical outcomes after acute illness. The present study was undertaken to investigate the plasma copeptin concentrations in preschool children with community-acquired pneumonia (CAP) and to analyze the correlations of copeptin with CAP-related complications and pleural effusion. Plasma copeptin concentrations of 100 healthy children and 165 preschool children with CAP were measured. 35 children (21.2%) presented with complicated CAP and 28 children (17.0%) presented with pleural effusion. The admission copeptin levels were significantly increased in all patients (49.7 ± 21.4 pmol/L), children with complicated CAP (73.0 ± 16.9 pmol/L), those with uncomplicated CAP (43.4 ± 17.8 pmol/L), those with pleural effusion (70.9 ± 17.4 pmol/L) and those without pleural effusion (45.3 ± 19.5 pmol/L) compared with healthy control individuals (9.0 ± 2.7 pmol/L, all P<0.001). Multivariate logistic regression analysis showed that plasma copeptin levels were independently related to CAP-related complications (odds ratio 1.214, 95% confidence interval 1.104-1.872, P<0.001) and pleural effusion (odds ratio 1.226, 95% confidence interval 1.109-1.917, P<0.001). A receiver operating characteristic curve analysis showed plasma copeptin level better predicted CAP-related complications (area under curve 0.876, 95% confidence interval 0.815-0.922) and pleural effusion (area under curve 0.831, 95% confidence interval 0.765-0.885). Thus, plasma copeptin level may represent a novel biomarker for predicting CAP-related complications in preschool children.