Calcitonin precursors: early markers of gut barrier dysfunction in patients with acute pancreatitis

Specificity of Presepsin as a Biomarker of Bacterial Infection in Mouse Sepsis Models

INTRODUCTION

Since its discovery in 2002, presepsin (P-SEP) has been reported to be useful in the early diagnosis of sepsis and has been evaluated in many clinical studies. However, as antibodies that bind to mouse P-SEP were previously unavailable, serum P-SEP levels in mice are limited. This study used a P-SEP enzyme-linked immunosorbent assay kit to evaluate the changes in serum P-SEP levels in mouse sepsis models compared with changes in other inflammatory markers and determine whether P-SEP can function as a biomarker specific to bacterial infections.

METHODS

Sepsis was induced in mice via cecal ligation and puncture (CLP), induction with lipopolysaccharide (LPS), and cecal ligation (CL) model was created as a control for the CLP model, following which clinical biomarkers (P-SEP, C-reactive protein, and procalcitonin) were evaluated.

RESULTS

The 48-h survival rates in the CLP, CL, and LPS-induced sepsis models were 67%, 89%, and 57%, respectively. Serum C-reactive protein levels did not increase in the CLP and CL models within 24 h but significantly increased in the LPS-induced sepsis model. Serum procalcitonin levels increased in the CLP and CL models and especially increased in the LPS-induced sepsis model. In contrast, an increase in serum P-SEP level was found in the CLP model at 6 h compared with those at baseline, the CL, and LPS-induced sepsis models.

CONCLUSIONS

Mouse P-SEP is elevated early in infection and more specific to bacterial infection compared with other biomarkers.

The role of procalcitonin as a prognostic factor for acute cholangitis and infections in acute pancreatitis: a prospective cohort study from a European single center

BACKGROUND

Infection in acute pancreatitis will worsen the disease prognosis. The aim of our study was to analyze the role of procalcitonin as a prognostic biomarker for infections and clinical severity.

METHOD

A prospective single-cohort observational study of patients diagnosed of acute pancreatitis (n = 152) was designed. PCT determination was tested on admission (first 72 h). Infections (biliary, extrapancreatic and infected pancreatic necrosis), need for antibiotics, urgent ERCP and severity scores for acute pancreatitis was assessed. ROC curves were designed and the area under the curve was calculated. Logistic regression for multivariate analysis was performed to evaluate the association between procalcitonin optimal cut-off level and major complications.

RESULTS

PCT >0.68 mg/dL had higher incidence of global infection, acute cholangitis, bacteraemia, infected pancreatic necrosis, use of antibiotics in general, and need for urgent ERCP. In the multivariate regressions analysis, PCT >0.68 mg/dL at admission demonstrated to be a strong risk factor for complications in acute pancreatitis.

DISCUSSION

PCT levels can be used as a reliable laboratory test to predict infections and the clinical severity of acute pancreatitis. High levels of PCT predict antibiotics prescription as well as the need for urgent ERCP in patients with concomitant clinically severe cholangitis.

Gene expression analysis in NSAID-induced rat small intestinal disease model with the intervention of berberine by the liquid chip technology

Objective

Investigate the effect and mechanism of berberine on the small intestinal mucosa of non-steroidal anti-inflammatory drugs (NSAIDs) related small intestinal injury.

Materials and methods

Twenty-four SD rats were randomly divided into control group, model group and intervention group. The model group and intervention group were treated with diclofenac (7.5 mg/kg·d, 2/d), a total of 4 days tube feeding, and the intervention group was treated with 50 mg/kg·d intragastric administration of berberine after 2 days. The control group was treated with 7.5 mg/kg·d, 2/d 0.9% saline tube feeding. Then we screened differential expression of colonic mucosal gene by the liquid chip technology.

Results

Compared with the control group, macroscopic and histology score of the model group increased significantly (P < 0.05), HTR4, HTR1a, F2RL3, CALCA, NPY, CRHR2, IL1b, P2RX3, TPH1, HMOX1, TRPV1, VIP, F2RL1, SLC6A4, TFF2, AQP8 content were significantly increased (P < 0.05), NOS1 content decreased significantly (P < 0.05); Compared with the model group, macroscopic and histology score of the intervention group improved significantly (P < 0.05), and HTR4, F2RL3, NPY, CRHR2, IL1b, VIP, AQP8 content were significantly lower (P < 0.05), NOS1 content increased significantly (P < 0.05).

Conclusion

Berberine has a protective effect on NSAID-associated small intestinal injury, the mechanism may be that berberine decreases the expression of intestinal mucosa HTR4, F2RL3, NPY, CRHR2, IL1b, VIP, AQP8, and increases the expression of NOS1, that to reduce intestinal permeability and protect intestinal mucosal barrier.

The relationships between LncRNA NNT-AS1, CRP, PCT and their interactions and the refractory mycoplasma pneumoniae pneumonia in children

To investigate the relationships between LncRNA NNT-AS1, CRP, PCT and their interactions and the refractory mycoplasma pneumoniae pneumonia (RMPP) in children. Serum levels of LncRNA NNT-AS1 of RMPP and non-RMPP (NRMPP) patients were detected by real-time PCR, and were analyzed together with serum c-reactive protein (CRP) and procalcitonin (PCT). Correlations between LncRNA NNT-AS1 and CRP and PCT were analyzed by Pearson correlation test. The ROC curve was used to analyze the potential of LncRNA NNT-AS1, CRP and PCT as biomarkers for predicting RMPP. Logistic regression crossover model and the Excel compiled by Andersson et al. were used to analyze the interactions among the biomarkers. We found that LncRNA NNT-AS1, CRP and PCT were all highly expressed in patients with RMPP. LncRNA NNT-AS1 could positively correlate with the expressions of CRP and PCT, and jointly promote the occurrence of RMPP. The combined diagnosis of LncRNA NNT-AS1, CRP and PCT could predict the occurrence of RMPP.

Inflammatory mediators in the diagnosis and treatment of acute pancreatitis: pentraxin-3, procalcitonin and myeloperoxidase

INTRODUCTION

Acute pancreatitis (AP) is the third most common gastrointestinal disease at hospital admission. The etiology and pathogenesis of this disease are not completely clear. Our study was intended to determine the systemic levels of pentraxin-3 (PTX-3), myeloperoxidase (MPO), procalcitonin (PCT), and C-reactive protein (CRP) as prognostic parameters in early stages of AP. We also determined the effects of treatment on PTX-3, MPO, PCT and CRP levels in AP.

MATERIAL AND METHODS

The study group comprised 44 AP patients (22 male, 22 female; age: 49.3 ±16.9 years) referred to our outpatient clinic. Additionally, our investigation included a control group of 30 healthy volunteers (18 male, 12 female; age: 50.8 ±12.6 years).

RESULTS

Leukocytes, glucose, aspartate aminotransferase (AST (SGOT)), alanine aminotransferase (ALT (SGPT)), alkaline phosphatase (ALP), total and direct bilirubin levels were significantly higher in the AP group (p < 0.05, all). CRP, PTX-3, MPO and PCT were considerably higher in the AP group (p < 0.001, all), and after treatment, CRP, PTX-3, MPO and PCT levels were significantly lower (p < 0.001, all).

CONCLUSIONS

Our findings indicated that the CRP, PTX-3, MPO and PCT levels increase in patients with AP and hence these indicators can be used as diagnostic factors to predict inflammation severity in AP. It was revealed that after treatment, there were significant reductions in biomarker levels. However, further research is needed in order to understand how these biomarkers can help to monitor inflammatory responses in AP.

Calcitonin gene-related peptide: neuroendocrine communication between the pancreas, gut, and brain in regulation of blood glucose

Background

Calcitonin gene-related peptide (CGRP), a ubiquitous neuropeptide, plays a diverse and intricate role in chronic low-grade inflammation, including conditions such as obesity, type 2 diabetes, and diabetes of the exocrine pancreas. Diabetes of exocrine pancreas is characterised by chronic hyperglycemia and is associated with persistent low-grade inflammation and altered secretion of certain pancreatic and gut hormones. While CGRP may regulate glucose homeostasis and the secretion of pancreatic and gut hormones, its role in chronic hyperglycemia after acute pancreatitis (CHAP) is not known. The aim of this study was to investigate the association between CGRP and CHAP.

Methods

Fasting blood samples were collected to measure insulin, HbA1c, CGRP, amylin, C-peptide, glucagon, pancreatic polypeptide (PP), somatostatin, gastric inhibitory peptide, glicentin, glucagon-like peptide-1 and 2, and oxyntomodulin. Modified Poisson regression analysis and linear regression analyses were conducted. Five statistical models were used to adjust for demographic, metabolic, and pancreatitis-related risk factors.

Results

A total of 83 patients were recruited. CGRP was significantly associated with CHAP in all five models (P-trend <0.005). Further, it was significantly associated with oxyntomodulin (P<0.005) and glucagon (P<0.030). Oxyntomodulin and glucagon independently contributed 9.7% and 7%, respectively, to circulating CGRP variance. Other pancreatic and gut hormones were not significantly associated with CGRP.

Conclusions

CGRP is involved in regulation of blood glucose in individuals after acute pancreatitis. This may have translational implications in prevention and treatment of diabetes of the exocrine pancreas.

Evaluating the use of procalcitonin in an asymptomatic, HIV-infected antiretroviral therapy-naïve, South African cohort

BACKGROUND

The chronic stage of human immunodeficiency virus (HIV) infection, although clinically asymptomatic, is characterized by activation of the immune system and persistent inflammation. Procalcitonin (PCT) has been studied in HIV infection as a marker of bacterial infection. Our aim was to assess the effect of persistent immune activation on PCT levels in asymptomatic treatment naïve HIV infected subjects.

METHODS

This was a cross-sectional study of 68 asymptomatic antiretroviral therapy-naive HIV infected participants and 42 uninfected controls. Stored serum samples were used to measure: PCT, interleukin-6 (IL-6), lipopolysaccharide binding protein (LBP), high sensitivity C-reactive protein (hsCRP), immunoglobulin G (IgG) and albumin. PCT was correlated with markers of: disease progression (CD4 count and viral load), immune activation (CD 38 on CD8+ T cells, IgG and LBP), inflammation (IL-6, hsCRP and albumin).

RESULTS

IL-6, IgG and CD8/38 were all significantly increased while albumin and CD4 counts were significantly lower in the HIV infected group. PCT levels were not significantly different between the two groups. There was no significant difference in LBP and hsCRP; however, their levels were increased in both groups. PCT correlated only with LBP (p=0.0001). IL-6 and LBP correlated positively with hsCRP and IgG. Albumin correlated inversely with IL-6 and viral load. Only IgG and CD8/38 correlated inversely with CD4 counts.

CONCLUSIONS

We demonstrated the activation of the innate (raised LBP), humoral (raised IgG) and cellular immune systems (increased CD8/38 T cells). Despite a state of persistent inflammation, PCT levels are not elevated in asymptomatic untreated HIV infection.

Early prediction of intestinal mucosal barrier function impairment by elevated serum procalcitonin in rats with severe acute pancreatitis

OBJECTIVES

The aim of this study was to evaluate serum procalcitonin (PCT) levels as a prognostic indicator of intestinal barrier function impairment in rats with severe acute pancreatitis (SAP).

METHODS

Thirty-six male Sprague Dawley rats were randomly grouped into SAP group (injected sodium taurocholate via biliopancreatic duct), Gln group (gavaged with glutamine after modeling), and control group. Blood, pancreatic, and terminal ileum tissues were obtained from the rats after 6 h of modeling. Serum amylase (Amy) levels were determined using an automatic biochemical detector, while endotoxin (ET), diamine oxidase (DAO), and PCT levels were measured by ELISA test. The pathology of pancreatic and small intestine tissues were observed. PCT protein expression in intestinal tissues were detected by immunohistochemistry and western blot.

RESULT

Pancreatic and intestinal injuries in Gln group were significantly lower than SAP group. Serum amylase, DAO, and PCT levels in SAP and Gln groups differed greatly and were significantly higher than control group. Immuno-histochemistry and western blot results showed that PCT protein expression levels in small intestine tissues of SAP group were higher than Gln group and control group. Serum PCT levels had a significant correlation with serum endotoxin, DAO levels and intestinal mucosal injury scores.

CONCLUSION

PCT expression in serum and intestinal tissues in SAP rats increased significantly in the early stages of SAP, and was closely related to the onset and degree of intestinal barrier function impairment. Thus, our results showed that measuring serum PCT can be used to predict intestinal mucosal barrier function impairment in SAP rats.

Meta-analysis of gut barrier dysfunction in patients with acute pancreatitis

BACKGROUND

The gut is implicated in the pathogenesis of acute pancreatitis but there is discrepancy between individual studies regarding the prevalence of gut barrier dysfunction in patients with acute pancreatitis. The aim of this study was to determine the prevalence of gut barrier dysfunction in acute pancreatitis, the effect of different co-variables, and changes in gut barrier function associated with the use of various therapeutic modalities.

METHODS

A literature search was performed using PRISMA and MOOSE guidelines. Summary estimates were presented as pooled prevalence of gut barrier dysfunction and the associated 95 per cent c.i.

RESULTS

A total of 44 prospective clinical studies were included in the systematic review, of which 18 studies were subjected to meta-analysis. The pooled prevalence of gut barrier dysfunction was 59 (95 per cent c.i. 48 to 70) per cent; the prevalence was not significantly affected by disease severity, timing of assessment after hospital admission or type of test used, but showed a statistically significant association with age. Overall, nine of 13 randomized clinical trials reported a significant improvement in gut barrier function following intervention compared with the control group, but only three of six studies that used standard enteral nutrition reported a statistically significant improvement in gut barrier function after intervention.

CONCLUSION

Gut barrier dysfunction is present in three of five patients with acute pancreatitis, and the prevalence is affected by patient age but not by disease severity. Clinical studies are needed to evaluate the effect of enteral nutrition on gut function in acute pancreatitis.

Initial procalcitonin level predicts infection and its outcome in patients with non-Hodgkin lymphoma with febrile neutropenia

We explored whether initially determined procalcitonin (PCT) levels could facilitate assessment of the risks of infection and death due to treatment failure in patients with non-Hodgkin lymphoma (NHL) with newly developed febrile neutropenia (FN). In the 212 examined episodes, the initial PCT value was markedly higher in patients with microbiologically documented infection (MDI) or clinically documented infection compared with patients with fevers of unknown origin (p < 0.001 for both). Patients with initial PCT values ≥ 0.50 ng/mL were at high risk of MDI (sensitivity 83.5%, specificity 77.2%). A significantly elevated PCT level was closely correlated with patient mortality (area under the curve [AUC] 0.864, 95% confidence interval [CI] 0.811-0.907, p < 0.001) and patients' admission to the intensive care unit (AUC 0.926, 95% CI 0.882-0.957, p < 0.001). In conclusion, the initially determined PCT value was a useful marker for identifying infection and predicting outcome in patients with NHL with FN.

Procalcitonin levels predict acute kidney injury and prognosis in acute pancreatitis: a prospective study

Background

Acute kidney injury (AKI) has been proposed as a leading cause of mortality for acute pancreatitis (AP) patients admitted to the intensive care unit (ICU). This study investigated the predictive value of procalcitonin (PCT) for AKI development and relevant prognosis in patients with AP, and compared PCT’s predictive power with that of other inflammation-related variables.

Methods

Between January 2011 and March 2013, we enrolled 305 cases with acute pancreatitis admitted to ICU. Serum levels of PCT, serum amyloid A (SAA), interleukin-6 (IL-6), and C reactive protein (CRP) were determined on admission. Serum PCT was tested in patients who developed AKI on the day of AKI occurrence and on either day 28 after occurrence (for survivors) or on the day of death (for those who died within 28 days).

Results

Serum PCT levels were 100-fold higher in the AKI group than in the non-AKI group on the day of ICU admission (p<0.05). The area under the receiver-operating characteristic (ROC) curve of PCT for predicting AKI was 0.986, which was superior to SAA, CRP, and IL-6 (p<0.05). ROC analysis revealed all variables tested had lower predictive performance for AKI prognosis. The average serum PCT level on day 28 (2.67 (0.89, 7.99) ng/ml) was significantly (p<0.0001) lower than on the day of AKI occurrence (43.71 (19.24,65.69) ng/ml) in survivors, but the serum PCT level on death (63.73 (34.22,94.30) ng/ml) was higher than on the day of AKI occurrence (37.55 (18.70,74.12) ng/ml) in non-survivors, although there was no significant difference between the two days in the latter group (p = 0.1365).

Conclusion

Serum PCT is superior to CRP, IL-6, and SAA for predicting the development of AKI in patients with AP, and also can be used for dynamic evaluation of AKI prognosis.

A comparison of the BISAP score and serum procalcitonin for predicting the severity of acute pancreatitis

BACKGROUND/AIMS

The bedside index of severity in acute pancreatitis (BISAP) is a new, convenient, prognostic multifactorial scoring system. As more data are needed before clinical application, we compared BISAP, the serum procalcitonin (PCT), and other multifactorial scoring systems simultaneously.

METHODS

Fifty consecutive acute pancreatitis patients were enrolled prospectively. Blood samples were obtained at admission and after 48 hours and imaging studies were performed within 48 hours of admission. The BISAP score was compared with the serum PCT, Ranson's score, and the acute physiology and chronic health examination (APACHE)-II, Glasgow, and Balthazar computed tomography severity index (BCTSI) scores. Acute pancreatitis was graded using the Atlanta criteria. The predictive accuracy of the scoring systems was measured using the area under the receiver-operating curve (AUC).

RESULTS

The accuracy of BISAP (≥ 2) at predicting severe acute pancreatitis was 84% and was superior to the serum PCT (≥ 3.29 ng/mL, 76%) which was similar to the APACHE-II score. The best cutoff value of BISAP was 2 (AUC, 0.873; 95% confidence interval, 0.770 to 0.976; p < 0.001). In logistic regression analysis, BISAP had greater statistical significance than serum PCT.

CONCLUSIONS

BISAP is more accurate for predicting the severity of acute pancreatitis than the serum PCT, APACHE-II, Glasgow, and BCTSI scores.

Predictors of adverse outcomes in acute pancreatitis: new horizons

Acute pancreatitis (AP) continues to be a clinical challenge. The mortality of patients with AP with adverse outcomes like organ failure and infected necrosis can be as high as 43 %. Highly accurate predictors of adverse outcomes are necessary to identify the high-risk patients so that they can be meticulously monitored and managed. However, there are no ideal predictors till date. Over the past several years, a number of single- and multi-parameter predictors have been identified and tested for prediction of adverse outcomes in AP. Out of the different tools tested, blood urea nitrogen and the harmless acute pancreatitis score appears to be useful and feasible in the management of AP under Indian conditions. Other single-parameter predictors like serum creatinine, hematocrit, erythrocyte sedimentation rate, C-reactive protein, and D-dimer need to be put to further tests in high-quality prospective studies with large sample size at the community level. Multi-parameter prediction tools like the bedside index of severity of acute pancreatitis may not be appealing in day-to-day clinical practice.

Infliximab enhances the therapeutic effectiveness of octreotide on acute necrotizing pancreatitis in rat model

OBJECTIVES

To investigate the synergistic activity of infliximab to the therapeutic effectiveness of octreotide in a rat model of acute necrotizing pancreatitis (ANP).

METHODS

Forty Sprague-Dawley rats were randomly divided into sham-operated group (SO), ANP group (ANP), octreotide group (OG), infliximab group (IG), and combination group (CG) (n = 8 in each group). The ANP model was induced by biliopancreatic duct injection with 4.5% of sodium taurocholate solution. Rats of the OG, IG, and CG were given a tail vein injection of octreotide (10 μg/kg), infliximab (8 mg/kg), and infliximab (8 mg/kg), respectively, combined with octreotide (10 μg/kg) at 6 hours after modeling. All rats in each group were killed at 24 hours after modeling. Serum biochemical indicator and partial pressure of arterial oxygen/fraction of inspired oxygen (PaO2/FiO2) of rats were determined. Pathological severity score of organs were evaluated.

RESULTS

The serum biochemical indicator and organs' pathology score of OG , IG, and CG were obviously lower than those in the ANP group, and those in the CG were the lowest (P < 0.05). The PaO2/FiO2 levels in the OG, IG, and CG were significantly higher than that in the ANP group (P < 0.05).

CONCLUSION

Infliximab could significantly lower the serum biochemical indicator, improve organs' function, and enhance the therapeutic effectiveness of octreotide on ANP.

Procalcitonin is a specific marker for detecting bacterial infection in patients with rheumatoid arthritis

OBJECTIVE

Rheumatoid arthritis (RA) is a chronic inflammatory disease accompanied by many complications, and serious infections are associated with many of the advanced therapeutics used to treat it. We assessed serum procalcitonin (PCT) levels to distinguish bacterial infection from other complications in patients with RA.

METHODS

One hundred eighteen patients experiencing an RA flare, noninfectious complication of RA or its treatment, nonbacterial infection, or bacterial infection were studied. Serum PCT concentrations were determined with a chemiluminescent enzyme immunoassay.

RESULTS

All patients experiencing an RA flare showed negative PCT levels (≤ 0.1 ng/ml; n = 18). The PCT level was higher in the bacterial infection group (25.8% had levels ≥ 0.5 ng/ml) than in the other 3 groups (0.0-4.3% had levels ≥ 0.5 ng/ml) and the difference was significant among groups (p = 0.003). Conversely, no statistically significant difference was observed among the groups with C-reactive protein (CRP) concentration ≥ 0.3 mg/dl (p = 0.513), white blood cell (WBC) count > 8500/mm(3) (p = 0.053), or erythrocyte sedimentation rate (ESR) > 15 mm/h (p = 0.328). The OR of high PCT level (≥ 0.5 ng/ml) for detection of bacterial infection was 19.13 (95% CI 2.44-149.78, p = 0.005). Specificity and positive likelihood ratio of PCT ≥ 0.5 ng/ml were highest (98.2% and 14.33, respectively) for detection of bacterial infection, although the sensitivity was low (25.8%).

CONCLUSION

Serum PCT level is a more specific marker for detection of bacterial infection than either CRP, ESR, or WBC count in patients with RA. High PCT levels (≥ 0.5 ng/ml) strongly suggest bacterial infection. However, PCT < 0.5 ng/ml, even if < 0.2 ng/ml, does not rule out bacterial infection and physicians should treat appropriately.

Established and novel biomarkers of sepsis

The increased incidence of sepsis, a systemic response to infection that occurs in some patients, has stimulated interest in identifying infected patients who are at risk and intervening early. When this condition progresses to severe sepsis (characterized by organ dysfunction), mortality is high. Hospitals that have implemented recommendations of the Surviving Sepsis Campaign have seen a reduction in mortality rate for hospital-acquired severe sepsis. They may reduce this further by focusing on new approaches to diagnosing sepsis, especially at an early stage. Sepsis is a complicated syndrome with many physiological derangements and many emerging laboratory markers of sepsis have been proposed as adjuncts to clinical evaluation. The list includes cytokines, acute phase proteins, neutrophil activation markers, markers of abnormal coagulation and, recently, markers of suppression of both the innate and adaptive immune response. The perfect biomarker would accurately identify patients at risk of developing severe sepsis and then guide targeted therapy.

Association between acute pancreatitis and peptic ulcer disease

AIM: To evaluate the relationship between peptic ulcer disease (PUD) and acute pancreatitis.

METHODS: A cohort of 78 patients with acute pancreatitis were included in this study. The presence of PUD and the Helicobacter pylori (H. pylori) status were assessed by an endoscopic method. The severity of acute pancreatitis was assessed using Ranson’s score, the Acute Physiology and Chronic Health Evaluation (APACHE) II score, computed tomography severity index and the clinical data during hospitalization, all of which were compared between the patients with and without PUD. The risk factors for PUD were also evaluated.

RESULTS: Among 78 patients, 41 patients (52.6%) with acute pancreatitis suffered from PUD, but only 13 (31.7%) patients with PUD were infected by H. pylori. On univariate analysis, male gender, an etiology of alcohol-induced pancreatitis, a history of smoking or alcohol consumption, elevated triglyceride and C-reactive protein levels, and high APACHE II score were significantly associated with PUD. However, on multivariate logistic regression analysis, the APACHE II score (odds ratio: 7.69; 95% confidence interval: 1.78-33.33; P < 0.01) was found to be the only independent risk factor for PUD.

CONCLUSION: Patients with acute pancreatitis are liable to suffer from PUD. PUD is associated with severe acute pancreatitis according to the APACHE II score, and treatment for PUD should be considered for patients with severe acute pancreatitis.

Gut barrier dysfunction in critically ill surgical patients with abdominal compartment syndrome

OBJECTIVES

This study investigated the effects of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) on gut barrier function in critically ill surgical patients.

METHODS

A prospective observational cohort study on patients with severe acute pancreatitis or abdominal sepsis admitted to an intensive care or high-dependency unit. Intra-abdominal pressure (IAP) and plasma levels of immunoglobulin G (IgG) and IgM antiendotoxin core antibodies (EndoCAb) and procalcitonin (ProCT) were measured serially.

RESULTS

Among 32 recruited patients, 24 (75%) and 8 patients (25%) developed IAH and ACS, respectively. The state of ACS was associated with significant reductions in plasma IgG EndoCAb (P = 0.015) and IgM EndoCAb (P = 0.016) and higher concentrations of plasma ProCT (P = 0.056) compared with absence of ACS. Resolution of IAH and ACS was associated with significant recovery of plasma IgG EndoCAb (P = 0.003 and P = 0.009, respectively) and IgM EndoCAb (P = 0.002 and P = 0.003, respectively) and reduction in plasma ProCT concentration (P = 0.049 and P = 0.019, respectively). Negative correlations were observed between IAP and plasma IgG EndoCAb (P = 0.003) and IgM EndoCAb (P = 0.002).

CONCLUSIONS

Intra-abdominal hypertension and ACS are associated with significantly higher endotoxin exposure and ProCT concentrations, suggestive of gut barrier dysfunction. Resolution of IAH and ACS is associated with evidence for recovery of gut barrier function.

Use of plasma procalcitonin levels as an adjunct to clinical microbiology

Procalcitonin (PCT) is synthesized by a large number of tissues and organs in response to invasion by pathogenic bacteria, fungi, and some parasites. Current PCT assays are rapid, specific, and of sufficient sensitivity to detect increases in PCT serum levels within 4 to 6 h of initiation of infection. Clinically, PCT levels may help in decisions regarding the need for empirical antibiotic therapy, "source control" of infection, and duration of antibiotic therapy. The addition of PCT levels to bacterial culture and viral detection results can assist with the separation of colonization and invasion by pathogenic bacteria.

Serum procalcitonin in systemic autoimmune diseases--where are we now?

OBJECTIVES

To review the current evidence regarding the value of measuring procalcitonin (PCT) levels in patients with systemic autoimmune diseases, with a focus on the evidence for diagnostic and analytical performance of this biomarker. A brief description of the pathophysiological basis of this biomarker is also included.

METHODS

Using PubMed from the National Library of Medicine, relevant English literature on PCT in patients with different systemic autoimmune diseases, from 1990 to 2009, was reviewed. The search used keywords referring to procalcitonin and systemic lupus erythematosus, antineutrophil cytoplasmic antibody-associated systemic vasculitis, Goodpasture syndrome, rheumatoid arthritis, and giant cell arteritis.

RESULTS

When used in the appropriate clinical setting, the measurement of serum PCT levels is valuable as a marker of severe systemic bacterial and fungal infections and sepsis. Information regarding plasma PCT levels in patients with active underlying systemic autoimmune diseases is limited, primarily from observational studies and case series, with considerable variability of patient characteristics and clinical settings. In the detection of systemic infection concomitant with autoimmune diseases, PCT had a diagnostic sensitivity of 53 to 100% and a specificity of 84 to 97% (depending on the selection criteria) and was superior to other inflammatory markers tested. Most of the studies used a semiquantitative test for PCT measurement (functional assay sensitivity <0.5 ng/mL), which can explain the low sensitivity of the test. PCT levels were not significantly affected by renal function abnormalities or immunosuppressive agents. Although high PCT levels commonly occurred with infection, elevated levels of PCT could be found in patients with vasculitis without evidence of infection, often correlated with high disease activity scores.

CONCLUSIONS

Significantly elevated PCT levels offer good specificity and sensitivity for systemic infection in patients with systemic autoimmune diseases, regardless of the use of corticosteroids or immunosuppressive agents. PCT measurement may add to diagnostic accuracy in patients with systemic autoimmune diseases who present with a febrile illness, especially when highly sensitive PCT assays and specific PCT cutoff ranges are used in a predefined clinical setting (reflecting the likelihood of infection versus an autoimmune disease flare). However, there are limitations when using this biomarker in patients with systemic autoimmune diseases. PCT levels should not replace the necessary extensive diagnostic workup, which should include a thorough history and physical examination, combined with appropriate immunological, microbiological, radiological, and histological data.

Procalcitonin in sepsis and systemic inflammation: a harmful biomarker and a therapeutic target

The worldwide yearly mortality from sepsis is substantial, greater than that of cancer of the lung and breast combined. Moreover, its incidence is increasing, and its response to therapy has not appreciably improved. In this condition, the secretion of procalcitonin (ProCT), the prohormone of calcitonin, is augmented greatly, attaining levels up to thousands of fold of normal. This hypersecretion emanates from multiple tissues throughout the body that are not traditionally viewed as being endocrine. The serum values of ProCT correlate with the severity of sepsis; they recede with its improvement and worsen with exacerbation. Accordingly, as highlighted in this review, serum ProCT has become useful as a biomarker to assist in the diagnosis of sepsis, as well as related infectious or inflammatory conditions. It is also a useful monitor of the clinical course and prognosis, and sensitive and specific assays have been developed for its measurement. Moreover, it has been demonstrated that the administration of ProCT to septic animals greatly increases mortality, and several toxic effects of ProCT have been elucidated by in vitro experimental studies. Antibodies have been developed that neutralize the harmful effects of ProCT, and their use markedly decreases the symptomatology and mortality of animals that harbour a highly virulent sepsis analogous to that occurring in humans. This therapy is facilitated by the long duration of serum ProCT elevation, which allows for a broad window of therapeutic opportunity. An experimental groundwork has been established that suggests a potential applicability of such therapy in septic humans.

Procalcitonin as a marker of severe bacterial infection in children in the emergency department

Procalcitonin, the prohormone of calcitonin, is a relatively new and innovative marker of bacterial infection that has multiple potential applications in the pediatric emergency department. In healthy individuals, circulating levels of procalcitonin are generally very low (<0.05 ng/mL), but in the setting of severe bacterial infection and sepsis, levels can increase by hundreds to thousands of fold within 4 to 6 hours. Although the exact physiologic function of procalcitonin has not been determined, the consistent response and rapid rise of this protein in the setting of severe bacterial infection make procalcitonin a very useful biomarker for invasive bacterial disease. In Europe, serum procalcitonin measurements are frequently used in the diagnosis and the management of patients in a variety of clinical settings. To date, the use of procalcitonin has been limited in the United States, but this valuable biomarker has many potential applications in both the pediatric emergency department and the intensive care unit. The intent of this article is to review the history of procalcitonin, describe the kinetics of the molecule in response to bacterial infection, describe the laboratory methods available for measuring procalcitonin, examine the main causes of procalcitonin elevation, and evaluate the potential applications of procalcitonin measurements in pediatric patients.

The value of procalcitonin at predicting the severity of acute pancreatitis and development of infected pancreatic necrosis: systematic review

BACKGROUND

Many studies have evaluated serum levels of procalcitonin (PCT) as a predictor in the development of severe acute pancreatitis (SAP) and infected pancreatic necrosis (IPN). This study assesses the value of PCT as a marker of development of SAP and IPN.

METHODS

Medline, Web of Science, the Cochrane clinical trials register, and international conference proceedings were searched systematically for prospective studies, which evaluated the usefulness of PCT as a marker of SAP and IPN. The sensitivity, specificity, and diagnostic odds ratios (DORs) were calculated for each study, and the study quality and heterogeneity among the studies were evaluated.

RESULTS

Twenty-four of 59 studies identified were included in data extraction. The sensitivity and specificity of PCT for development of SAP were 0.72 and 0.86, respectively (area under the curve [AUC] = 0.87; DOR = 14.9; 95% confidence interval [CI] = 5.6-39.8), albeit with a significant degree of heterogeneity (Q = 28.56, P < .01). The sensitivity and specificity of PCT for prediction of infected pancreatic necrosis were 0.80 and 0.91 (AUC = 0.91; DOR = 28.3; 95% CI = 13.8-58.3) with no significant heterogeneity (Q = 7.83, P = .18). No significant heterogeneity was observed among the studies when only higher quality studies (AUC = 0.91; DOR = 30.7; 95% CI = 10.7-87.8) or studies that used a cutoff PCT level >0.5 ng/mL (AUC = 0.88, 32.8; 95% CI = 10.1-106.6) were included.

CONCLUSION

Serum measurements of PCT may be valuable in predicting the severity of acute pancreatitis and the risk of developing infected pancreatic necrosis.

Advancement of intestinal function disorders in severe acute pancreatitis

Recent studies indicate that increased intestinal permeability and changes of intestinal mucosal immune function are very common in patients with severe acute pancreatitis (SAP). And they may be the main reasons for bacterial and endotoxin translocation, which are associated with secondary infection and multiorgan dysfunction syndrome in SAP. However, the accurate mechanism underlying the abnormality of intestinal mucosal immune dysfunction is not clarified, which deserves further study.

Assessment of the prognostic value of certain acute-phase proteins and procalcitonin in the prognosis of acute pancreatitis

OBJECTIVES

Of patients with acute pancreatitis (AP), 20% develop severe attacks that need early and intensive therapy. Yet, to administer such treatment, it is important to classify early on the patients with mild and severe pancreatitis. The aim of this study was to evaluate the role of serum amyloid A, C-reactive protein, procalcitonin, and routinely measured parameters in the early prediction of the course of AP.

METHODS

A total of 40 consecutive patients with AP confirmed by computed tomography were prospectively enrolled in the study-29 were graded as mild and 11 were graded as severe. Blood samples were obtained on admission and 24 hours thereafter.

RESULTS

Procalcitonin concentration in both measurements was significantly higher in patients with severe pancreatitis, and the cutoff level was estimated at 0.5 ng/mL. Although serum amyloid A and C-reactive protein levels rose significantly during the period of observation, these were not differentiated between both groups. Among the routinely measured parameters, a prognostic value was found for total calcium concentration, lactic dehydrogenase activity, and glucose concentration.

CONCLUSIONS

The best efficiency in the early prediction of severe AP would be achieved with the measurement of procalcitonin, total calcium level, and lactic acid dehydrogenase activity immediately after admission to the ward.

Procalcitonin assay in systemic inflammation, infection, and sepsis: clinical utility and limitations

OBJECTIVE

The use of procalcitonin (ProCT) as a marker of several clinical conditions, in particular, systemic inflammation, infection, and sepsis, will be clarified, and its current limitations will be delineated. In particular, the need for a more sensitive assay will be emphasized. For these purposes, the medical literature comprising clinical studies pertaining to the measurement of serum ProCT in various clinical settings was examined.

DATA SOURCE AND SELECTION

A PubMed search (1965 through November 2007) was conducted, including manual cross-referencing. Pertinent complete publications were obtained using the MeSH terms procalcitonin, C-reactive protein, sepsis, and biological markers. Textbook chapters were also read and extracted.

DATA EXTRACTION AND SYNTHESIS

Available clinical and other patient data from these sources were reviewed, including any data relating to precipitating factors, clinical findings, associated illnesses, and patient outcome. Published data concerning sensitivity, specificity, and reproducibility of ProCT assays were reviewed.

CONCLUSIONS

Based on available data, the measurement of serum ProCT has definite utility as a marker of severe systemic inflammation, infection, and sepsis. However, publications concerning its diagnostic and prognostic utility are contradictory. In addition, patient characteristics and clinical settings vary markedly, and the data have been difficult to interpret and often extrapolated inappropriately to clinical usage. Furthermore, attempts at meta-analyses are greatly compromised by the divergent circumstances of reported studies and by the sparsity and different timing of the ProCT assays. Although a high ProCT commonly occurs in infection, it is also elevated in some noninfectious conditions. Thus, the test is not a specific indicator of either infection or sepsis. Moreover, in any individual patient, the precipitating cause of an illness, the clinical milieu, and complicating conditions may render tenuous any reliable estimations of severity or prognosis. It also is apparent that even a febrile septic patient with documented bacteremia may not necessarily have a serum ProCT that is elevated above the limit of functional sensitivity of the assay. In this regard, the most commonly applied assay (i.e., LUMItest) is insufficiently sensitive to detect potentially important mild elevations or trends. Clinical studies with a more sensitive ProCT assay that is capable of rapid and practicable day-to-day monitoring are needed and shortly may be available. In addition, investigations showing that ProCT and its related peptides may have mediator relevance point to the need for evaluating therapeutic countermeasures and studying the pathophysiologic effect of hyperprocalcitonemia in serious infection and sepsis.

Early assessment of pancreatic infections and overall prognosis in severe acute pancreatitis by procalcitonin (PCT): a prospective international multicenter study

BACKGROUND

Pancreatic infections and sepsis are major complications in severe acute pancreatitis (AP) with significant impact on management and outcome. We investigated the value of Procalcitonin (PCT) for identifying patients at risk to develop pancreatic infections in severe AP.

METHODS

A total of 104 patients with predicted severe AP were enrolled in five European academic surgical centers within 96 hours of symptom onset. PCT was measured prospectively by a semi-automated immunoassay in each center, C-reactive protein (CRP) was routinely assessed. Both parameters were monitored over a maximum of 21 consecutive days and in weekly intervals thereafter.

RESULTS

In contrast to CRP, PCT concentrations were significantly elevated in patients with pancreatic infections and associated multiorgan dysfunction syndrome (MODS) who all required surgery (n = 10) and in nonsurvivors (n = 8) early after onset of symptoms. PCT levels revealed only a moderate increase in patients with pancreatic infections in the absence of MODS (n = 7), all of whom were managed nonoperatively without mortality. A PCT value of > or =3.5 ng/mL on 2 consecutive days was superior to CRP > or =430 mg/L for the assessment of infected necrosis with MODS or nonsurvival as determined by ROC analysis with a sensitivity and specificity of 93% and 88% for PCT and 40% and 100% for CRP, respectively (P < 0.01). The single or combined prediction of the two major complications was already possible on the third and fourth day after onset of symptoms with a sensitivity and specificity of 79% and 93% for PCT > or =3.8 ng/mL compared with 36% and 97% for CRP > or =430 mg/L, respectively (P = 0.002).

CONCLUSION

Monitoring of PCT allows early and reliable assessment of clinically relevant pancreatic infections and overall prognosis in AP. This single test parameter significantly contributes to an improved stratification of patients at risk to develop major complications.

Does serum procalcitonin have a role in evaluating the severity of acute pancreatitis? A question revisited

PURPOSE

This study was designed to evaluate the diagnostic accuracy of serum procalcitonin (PCT) for the diagnosis of severity in acute pancreatitis (AP), compared with routine clinical, biochemical, radiological, and combination severity scoring systems.

METHODS

Quantitative meta-analysis was performed on prospective studies, comparing serum PCT, against validated scoring systems for diagnosing severe AP. The sensitivity, specificity, and diagnostic odds ratio were calculated for each study. Summary receiver operating characteristic (SROC) curves and subgroup analysis were undertaken. Study quality and heterogeneity were evaluated. Meta-regression meta-analysis was used to evaluate the effect of using serum PCT in the diagnostic accuracy severity scoring in AP.

RESULTS

Summary receiver operating characteristic analysis of nine studies showed an overall sensitivity and specificity of 74% (range: 66%-81%) and 83% (range: 79%-87%), respectively. Overall unweighted area under the curve (AUC) was 0.91 (DOR = 16.26 95% CI: 5.68-46.60), demonstrating significant heterogeneity (Q-value = 25.32; P = 0.001). When high-quality studies alone were evaluated, there was an increase in the overall sensitivity (89%); however, specificity was similar (82%), with an overall unweighted AUC of 0.94 (DOR 41.46, 95% CI: 17.95-95.80), with no significant heterogeneity. Meta-regression analysis confirmed the significant effect of study quality on the diagnostic accuracy of severity scoring using serum PCT (P = 0.025).

CONCLUSIONS

The use of PCT for severity scoring in AP has a moderate sensitivity but higher specificity. However, the overall accuracy for predicting severity in AP is high. The prognosis of severity, especially early on (<48 hours from onset of symptoms), and the evaluation of potential infectious complications of AP may be the most useful factors to assess in subsequent clinical trials to identify its exact application in clinical practice in the management of AP.

Procalcitonin: improved biochemical severity stratification and postoperative monitoring in severe abdominal inflammation and sepsis

BACKGROUND

Infections and sepsis are among the most devastating complications in abdominal surgery and significantly contribute to morbidity and mortality. Early and reliable diagnosis of septic complications is notoriously difficult, and the search for novel approaches to overcome this problem is still a compelling issue for clinicians. Among a large array of inflammatory parameters, procalcitonin (PCT), the 116-amino-acid pro-peptide of calcitonin, has gained considerable importance in identifying patients at risk of developing infection and sepsis in clinical practice.

METHODS

Along with the latest insights into pathophysiological aspects of this pro-hormone, the literature as well as our own experience on the usefulness of PCT determinations in patients with severe inflammatory abdominal disorders was reviewed.

RESULTS

Although the term "sepsis" does not embrace the integral properties of PCT, a remarkable number of clinical studies have demonstrated the pivotal role of this parameter in the host response to microbial and fungal infections. In acute pancreatitis PCT allows early severity stratification and closely correlates with the development of subsequent pancreatic infections. In patients with peritonitis PCT reflects overall disease severity and is an early and reliable indicator of overall prognosis. Postoperative monitoring of PCT is a helpful tool to identify patients with evolving or persisting septic complications after elective and emergency abdominal surgery.

CONCLUSIONS

Compared with established biochemical routine variables, PCT significantly contributes to earlier and better stratification of patients at risk of developing septic complications and provides excellent prognostic assessment in severe abdominal inflammation. The currently available test systems render PCT an applicable and readily available parameter under clinical routine and emergency conditions.