Procalcitonin as a biomarker for bacterial infections in patients with liver cirrhosis in the emergency department

Comparison of the diagnostic accuracy of monocyte distribution width and procalcitonin in sepsis cases in the emergency department: a prospective cohort study

Background

Early diagnosis and treatment of patients with sepsis reduce mortality significantly. In terms of exploring new diagnostic tools of sepsis, monocyte distribution width (MDW), as part of the white blood cell (WBC) differential count, was first reported in 2017. MDW greater than 20 and abnormal WBC count together provided a satisfactory accuracy and was proposed as a novel diagnostic tool of sepsis. This study aimed to compare MDW and procalcitonin (PCT)’s diagnostic accuracy on sepsis in the emergency department.

Methods

This was a single-center prospective cohort study. Laboratory examinations including complete blood cell and differentiation count (CBC/DC), MDW, PCT were obtained while arriving at the ED. We divided patients into non-infection, infection without systemic inflammatory response syndrome (SIRS), infection with SIRS, and sepsis-3 groups. This study’s primary outcome is the sensitivity and specificity of MDW, PCT, and MDW + WBC in differentiating septic and non-septic patients. In addition, the cut-off value for MDW was established to maximize sensitivity at an optimal level of specificity.

Results

From May 2019 to September 2020, 402 patients were enrolled for data analysis. Patient number in each group was: non-infection 64 (15.9%), infection without SIRS 82 (20.4%), infection with SIRS 202 (50.2%), sepsis-3 15 (7.6%). The AUC of MDW, PCT, and MDW + WBC to predict infection with SIRS was 0.753, 0.704, and 0.784, respectively (p < 0.01). The sensitivity, specificity, PPV, and NPV of MDW using 20 as the cutoff were 86.4%, 54.2%, 76.4%, and 70%, compared to 32.9%, 88%, 82.5%, and 43.4% using 0.5 ng/mL as the PCT cutoff value. On combing MDW and WBC count, the sensitivity and NPV further increased to 93.4% and 80.3%, respectively. In terms of predicting sepsis-3, the AUC of MDW, PCT, and MDW + WBC was 0.72, 0.73, and 0.70, respectively. MDW, using 20 as cutoff, exhibited sensitivity, specificity, PPV, and NPV of 90.6%, 37.1%, 18.7%, and 96.1%, respectively, compared to 49.1%, 78.6%, 26.8%, and 90.6% when 0.5 ng/mL PCT was used as cutoff.

Conclusions

In conclusion, MDW is a more sensitive biomarker than PCT in predicting infection-related SIRS and sepsis-3 in the ED. MDW < 20 shows a higher NPV to exclude sepsis-3. Combining MDW and WBC count further improves the accuracy in predicting infection with SIRS but not sepsis-3.

Trial registration The study was retrospectively registered to the ClinicalTrial.gov (NCT04322942) on March 26th, 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06999-4.

Update on blood-based biomarkers for chronic liver diseases prognosis: Literature review and institutional experience

Liver cirrhosis is the final stage of chronic liver disease (CLD) and is associated with high morbidity and mortality. Various complications such as portal hypertension, ascites retention, hepatic encephalopathy, and hepatorenal syndrome deeply affect patient outcome. The most common tools to predict the outcome of a CLD patient include the following: assessing severity of portal hypertension; scoring systems such as the model of end-stage liver disease and Child-Pugh score and blood biomarkers related to complications and/or survival rate. In this article, we summarize recent studies of noninvasive markers for predicting impending complications related to CLD and discuss the clinical value of currently available blood biomarkers based on evidence from the literature. In addition, noninvasive blood biomarker assays for different prognostic functions were validated on 113 liver cirrhosis patients at our institution using Kaplan-Meier curve analysis to confirm that these markers can satisfactorily predict CLD-related patient death.

Diagnostic and prognostic role of presepsin in patients with cirrhosis and bacterial infection

Objectives

Serum biomarkers have suboptimal accuracy for the early diagnosis of bacterial infection (BI) in cirrhosis.

Aim

To evaluate the diagnostic and prognostic accuracy of presepsin (PSP) in a cohort of hospitalized patients with cirrhosis.

Methods

All adult cirrhotics admitted between 03.2016 and 06.2019 were consecutively evaluated. PSP was measured using chemiluminescent enzyme immunoassay, and its accuracy was compared with that of common biomarkers.

Results

A total of 278 cirrhotic patients for a total of 448 hospitalizations were prospectively collected. Prevalence of BI at admission was 28.3%. Median (range) Log10PSP in the whole cohort was 2.83 (2.48-3.19) ng/L, significantly higher in patients with BI than in patients without (p<0.001). For a cutoff value of 2.87 ng/L, Log10PSP showed sensitivity, specificity and AUC-ROC of 0.66 (95% CI 0.57-0.74), 0.63 (95% CI 0.57-0.68) and 0.69 (95% CI 0.63-0.73), lower than that of C-reactive protein (p=0.002), but similar to procalcitonin (p=0.18) Patients with BI at hospitalization had higher probability of 28-day mortality (sub-hazard ratio [sHR] 2.65;95% CI 1.49-4.70; p=0.001). At multivariate Cox's regression analysis, Log10PSP (sHR 2.4; 95% CI 1.22-4.82; p=0.01) together with age and severity of liver disease, was an independent predictor of short-term mortality.

Conclusions

PSP shows low diagnostic accuracy for BI in cirrhosis, but it is an independent predictor of short-term mortality. PSP may be a biomarker of systemic inflammation, commonly seen in end-stage liver disease.

Rush progression and fatal result of septic shock related to central line catheter infection in cirrhosis patient with brain stroke

BACKGROUND

Catheter-related blood stream infection (CRBSI) is one of the most common intractable healthcare-associated infections because catheters can be easily contaminated by resistant bacteria, and is associated with a high mortality. Central lines are currently used for administering medication to patients with severe stroke, and may thus cause CRBSI.

CASE PRESENTATION

A 71-year-old woman with cirrhosis presented with subarachnoid hemorrhage (SAH) that was treated by clipping surgery. On postoperative day (POD) 38, sudden high fever (40.3 °C) was detected; the patient died a few hours later. Blood and central line cultures were positive for Klebsiella pneumoniae that may have caused CRBSI and endotoxin shock. In this case, the duration from fever detection to death was notably short. Additionally, inflammatory markers such as white blood cells (WBC) or C-reactive protein (CRP) were almost within normal ranges, even a few hours after fever was detected and before death. Cirrhosis was considered to be the cause of these phenomena.

CONCLUSION

The timely diagnosis and complete treatment of patients with liver cirrhosis who develop CRBSI are highly challenging. We suggest that clinicians should rigorously apply preventive measures and strengthen CRBSI monitoring, especially in cirrhosis-associated cases.

Management of Infectious Complications Associated with Acute-on-Chronic Liver Failure

Introduction

Acute-on-chronic liver failure (ACLF) is associated with a high susceptibility to infections leading to complications and poor prognosis. The sensitized immune system overwhelmingly responds to invading bacteria leading to organ damage. After resolution of infection or prolonged disease duration, the phagocytic system becomes irresponsive with a reduced bacterial clearance capacity promoting secondary infection.

Methods

This review focuses on the best management strategies for patients with ACLF and infections. Using the following terms, an extensive literature research on the Medline database was performed: 'acute-on-chronic liver failure', 'infection', 'ACLF', 'bacteria', 'multi-resistance'.

Results

Analysis of the literature confirmed that delayed diagnosis and treatment of infections in patients with ACLF results in a poor prognosis. Patients with ACLF should be considered as having a potential infection and should undergo a complete screening for sepsis. Once biochemical analysis indicates a potential infection, such as abnormal levels of C-reactive protein and procalcitonin, antibiotic treatment should be initiated immediately without microbiological culture results. For community-acquired infections third-generation cephalosporins are still the first choice, whereas in the nosocomial setting antibiotics with broader spectrum, such as piperacillin/combactam or carbapenems ± glycopeptides, are preferred. The patient should be re-assessed 48 h after treatment initiation in order to tailor the treatment. Non-response is suspicious, likely due to bacterial resistance or fungal infection, which should be considered when choosing further treatment strategies. Albumin substitution to prevent hepatorenal syndrome and to improve patients' outcome is mandatory in patients with spontaneous bacterial peritonitis. Prophylactic antibiotic therapy is suitable to prevent infections in high-risk patients.

Conclusion

The screening for infections and its treatment is an essential part of managing patients with ACLF. In order to improve patients' prognosis, antibiotic treatment should be initiated once an infection is suspected. However, preventive strategies are already established and should be applied according to the guidelines.

Immune Dysfunction in Cirrhosis

Cirrhosis due to any etiology disrupts the homeostatic role of liver in the body. Cirrhosis-associated immune dysfunction leads to alterations in both innate and acquired immunity, due to defects in the local immunity of liver as well as in systemic immunity. Cirrhosis-associated immune dysfunction is a dynamic phenomenon, comprised of both increased systemic inflammation and immunodeficiency, and is responsible for 30% mortality. It also plays an important role in acute as well as chronic decompensation. Immune paralysis can accompany it, which is characterized by increase in anti-inflammatory cytokines and suppression of proinflammatory cytokines. There is also presence of increased gut permeability, reduced gut motility and altered gut flora, all of which leads to increased bacterial translocation. This increased bacterial translocation and consequent endotoxemia leads to increased blood stream bacterial infections that cause systemic inflammatory response syndrome, sepsis, multiorgan failure and death. The gut microbiota of cirrhotic patients has more pathogenic microbes than that of non-cirrhotic individuals, and this disturbs the homeostasis and favors gut translocation. Prompt diagnosis and treatment of such infections are necessary for better survival. We have reviewed the various mechanisms of immune dysfunction and its consequences in cirrhosis. Recognizing the exact pathophysiology of immune dysfunction will help treating clinicians in avoiding its complications in their patients and can lead to newer therapeutic interventions and reducing the morbidity and mortality rates.

Serum Procalcitonin in Patients with Acute Liver Failure

BACKGROUND

Procalcitonin (PCT) is a known diagnostic marker of bacterial infection. There are no previous reports of PCT concerning acute liver failure (ALF). We evaluated the clinical value of serum PCT levels in patients with ALF.

METHODS

Forty-four patients with acute hepatitis (19 men and 25 women; median age, 40 years; range, 20-79 years) were retrospectively enrolled from January 2001 and June 2015. PCT levels were measured by saved serum samples obtained within 3 days after admission. ALF was defined as prothrombin time (PT) < 40% regardless of hepatic encephalopathy.

RESULTS

Serum PCT levels were significantly higher in the patients with ALF (n = 16) than in those with non-ALF (n = 28) [0.25 (0.13-2.66) ng/mL vs. 0.165 (0.03-1.08), P = 0.00967]. Creatinine, total bilirubin, and direct bilirubin were positively correlated, and PT was negatively correlated with PCT. Receiver operating characteristic curve analysis showed an area under the curve of 0.74 for detecting ALF. With a PCT cut-off value of 0.5 ng/mL, the presence of ALF could be demonstrated with low sensitivity (37.5%) and high specificity (96.5%) with high positive (85.7%) and negative (72.9%) predictive value. Multivariate analysis showed that PCT was an independent factor associated with the presence of ALF. The cumulative survival rate was also significantly lower in patients with PCT ≥ 0.5 ng/mL (P = 0.0314), but it was not an independent prognostic factor.

CONCLUSION

Serum PCT level was significantly higher in patients with ALF.

Presepsin teardown - pitfalls of biomarkers in the diagnosis and prognosis of bacterial infection in cirrhosis

AIM

To evaluate the diagnostic and prognostic value of presepsin in cirrhosis-associated bacterial infections.

METHODS

Two hundred and sixteen patients with cirrhosis were enrolled. At admission, the presence of bacterial infections and level of plasma presepsin, serum C-reactive protein (CRP) and procalcitonin (PCT) were evaluated. Patients were followed for three months to assess the possible association between presepsin level and short-term mortality.

RESULTS

Present 34.7 of patients had bacterial infection. Presepsin levels were significantly higher in patients with infection than without (median, 1002 pg/mL vs 477 pg/mL, P < 0.001), increasing with the severity of infection [organ failure (OF): Yes vs No, 2358 pg/mL vs 710 pg/mL, P < 0.001]. Diagnostic accuracy of presepsin for severe infections was similar to PCT and superior to CRP (AUC-ROC: 0.85, 0.85 and 0.66, respectively, P = NS for presepsin vs PCT and P < 0.01 for presepsin vs CRP). At the optimal cut-off value of presepsin > 1206 pg/mL sensitivity, specificity, positive predictive values and negative predictive values were as follows: 87.5%, 74.5%, 61.8% and 92.7%. The accuracy of presepsin, however, decreased in advanced stage of the disease or in the presence of renal failure, most probably because of the significantly elevated presepsin levels in non-infected patients. 28-d mortality rate was higher among patients with > 1277 pg/mL compared to those with ≤ 1277 pg/mL (46.9% vs 11.6%, P < 0.001). In a binary logistic regression analysis, however, only PCT (OR = 1.81, 95%CI: 1.09-3.01, P = 0.022) but neither presepsin nor CRP were independent risk factor for 28-d mortality after adjusting with MELD score and leukocyte count.

CONCLUSION

Presepsin is a valuable new biomarker for defining severe infections in cirrhosis, proving same efficacy as PCT. However, it is not a useful marker of short-term mortality.

Sepsis in cirrhosis: emerging concepts in pathogenesis, diagnosis and management

Infections and sepsis are more common in cirrhotic than in the general population and constitute the commonest cause of sudden worsening and death. The diagnosis of systemic inflammatory syndrome and sepsis are challenging in cirrhotics due to an underlying a state of hyperdynamic circulation. Further, poor nutritional and bone marrow reserves lead to modest host immune response, the so called immunoparalysis state and the outcome of antibiotic therapy is suboptimal. In this review, a comprehensive description of current and emerging concepts in the pathogenesis and diagnosis of sepsis with importance to current and novel biomarkers for diagnosis of sepsis in cirrhosis is presented. Furthermore, novel treatment options and preventive strategies are discussed to improve the overall survival.

Impact of hepatic function on serum procalcitonin for the diagnosis of bacterial infections in patients with chronic liver disease: A retrospective analysis of 324 cases

Although procalcitonin (PCT) is a valid marker for early diagnosis of bacterial infections, it is unclear whether its accuracy in predicting bacterial infections is affected by impaired liver function. This study aimed to assess the impact of compromised liver function on the diagnostic value of PCT.This retrospective study was conducted between January 2013 and May 2015. A total of 324 patients with chronic liver disease were enrolled. Routine laboratory measurements and PCT were performed. Patients were divided into 3 groups according to clinical diagnosis: chronic hepatitis (group 1), decompensated cirrhosis (group 2), and acute-on-chronic liver failure/chronic liver failure (group 3). The correlation between PCT and liver function was analyzed. The area under the receiver operating characteristic (AUCROC) curve of PCT was analyzed according to infection status and liver function.PCT was more accurate than white blood cell count (P < 0.001) and percentage of neutrophils (P < 0.001) in detecting bacterial infections in patients with impaired liver function. In patients without infection, PCT had a moderate positive correlation with serum total bilirubin (TBIL) (r = 0.592), and a weak correlation with model for end-stage liver disease score (r = 0.483) and international normalized ratio (r = 0.389). The AUCROC and optimum thresholds of PCT and for predicting bacterial infections at different levels of TBIL were 0.907 (95% CI 0.828-0.958) and 0.38 ng/mL, respectively, for TBIL <5 mg/dL, 0.927 (95% CI 0.844-0.974) and 0.54 ng/mL (5 mg/dL ≤TBIL<10 mg/dL), 0.914 (95% CI 0.820-0.968) and 0.61 ng/mL (10 mg/dL ≤TBIL<20 mg/dL), 0.906 (95% CI 0.826-0.958) and 0.94 ng/mL (TBIL ≥20 mg/dL), respectively.This study demonstrated that PCT was a valuable marker of bacterial infection in patients with chronic liver diseases. TBIL affected PCT threshold, so different cut-offs should be used according to different TBIL values.

Markers of bacterial translocation in end-stage liver disease

Bacterial translocation (BT) refers to the passage of viable bacteria or bacterial products from the intestinal lumen, through the intestinal epithelium, into the systemic circulation and extraintestinal locations. The three principal mechanisms that are thought to be involved in BT include bacterial overgrowth, disruption of the gut mucosal barrier and an impaired host defence. BT is commonly observed in liver cirrhosis and has been shown to play an important role in the pathogenesis of the complications of end stage liver disease, including infections as well as hepatic encephalopathy and hepatorenal syndrome. Due to the importance of BT in the natural history of cirrhosis, there is intense interest for the discovery of biomarkers of BT. To date, several such candidates have been proposed, which include bacterial DNA, soluble CD14, lipopolysaccharides endotoxin, lipopolysaccharide-binding protein, calprotectin and procalcitonin. Studies on the association of these markers with BT have demonstrated not only promising data but, oftentimes, contradictory results. As a consequence, currently, there is no optimal marker that may be used in clinical practice as a surrogate for the presence of BT.

Clinical characteristics and prognostic impact of bacterial infection in hospitalized patients with alcoholic liver disease

Bacterial infection is an important cause of death in patients with liver cirrhosis. The aim of this study was to investigate the clinical characteristics and prognostic impact of bacterial infection in hospitalized patients with alcoholic liver disease (ALD). We retrospectively analyzed data from 409 patients consecutively admitted to a tertiary referral center with ALD diagnosis. Of a total of 544 admissions, 133 (24.4%) cases presented with bacterial infection, of which 116 were community-acquired whereas 17 were hospital-acquired. The common types of infection were pneumonia (38%), biliary tract infection (17%), soft tissue infection (12%), and spontaneous bacterial peritonitis (9%). Diabetes, serum Na <135 mM/L, albumin <2.5 g/dL, C-reactive protein ≥20 mg/L, systemic inflammatory response syndrome (SIRS) positivity were independently associated with bacterial infection in patients with ALD. Overall 30-day and 90-day mortalities in patients with bacterial infection were significantly (P < 0.001) higher than those without infection (22.3% vs. 5.1% and 32.3% vs. 8.2%, respectively). Furthermore, bacterial infection (HR, 2.2; 95% CI, 1.049-4.579, P = 0.037), SIRS positivity (HR, 2.5; 95% CI, 1.240-4.861, P = 0.010), Maddrey's discriminant function score ≥32 (HR, 2.3; 95% CI, 1.036-5.222, P = 0.041), and hemoglobin <12 g/dL (HR, 2.4; 95% CI, 1.081-5.450, P = 0.032) were independent predictors of short-term mortality. In conclusion, bacterial infection and SIRS positivity predicted short-term prognosis in hospitalized patients with ALD. A thorough evaluation at admission or on clinical deterioration is required to detect possible infection with prompt management.

Measurement of serum procalcitonin levels for the early diagnosis of spontaneous bacterial peritonitis in patients with decompensated liver cirrhosis

Background

It is difficult to diagnose spontaneous bacterial peritonitis (SBP) early in decompensated liver cirrhotic ascites patients (DCPs). The aim of the study was to measure serum procalcitonin (PCT) levels and peripheral blood leukocyte/platelet (WBC/PLT) ratios to obtain an early diagnostic indication of SBP in DCPs.

Methods

Our cohort of 129 patients included 112 DCPs (94 of whom had infections) and 17 cases with compensated cirrhosis as controls. Bacterial cultures, ascitic fluid (AF) leukocyte and peripheral WBC/PLT counts, and serum PCT measurements at admission were carried out prior to the use of antibiotics. Receiver operating characteristic (ROC) curves were generated to test the accuracies and cut-off values for different inflammatory markers.

Results

Among the 94 infected patients, 66 tested positive by bacterial culture, for which the positivity of blood, ascites and other secretions were 25.8%, 30.3% and 43.9%, respectively. Lung infection, SBP and unknown sites of infection accounted for 8.5%, 64.9% and 26.6% of the cases, respectively. Serum PCT levels (3.02 ± 3.30 ng/mL) in DCPs with infections were significantly higher than those in control patients (0.15 ± 0.08 ng/mL); p < 0.05. We used PCT ≥0.5 ng/mL as a cut-off value to diagnose infections, for which the sensitivity and specificity was 92.5% and 77.1%. The area under the curve (AUC) was 0.89 (95% confidence interval: 0.84–0.91). The sensitivity and specificity were 62.8% and 94.2% for the diagnosis of infections, and were 68.8% and 94.2% for the diagnosis of SBP in DCPs when PCT ≥2 ng/mL was used as a cut-off value. For the combined PCT and WBC/PLT measurements, the sensitivity was 76.8% and 83.6% for the diagnosis of infections or SBP in DCPs, respectively.

Conclusion

Serum PCT levels alone or in combination with WBC/PLT measurements seem to provide a satisfactory early diagnostic biomarker in DCPs with infections, especially for patients with SBP.

Procalcitonin as a marker of sepsis in alcoholic hepatitis

BACKGROUND

Early diagnosis of sepsis in alcoholic hepatitis is important for selecting the appropriate therapy. The role of procalcitonin (PCT) to diagnose sepsis in patients with alcoholic hepatitis and systemic inflammatory response syndrome (SIRS) is not yet clear.

METHODS

All patients admitted with alcoholic hepatitis and SIRS underwent measurement of serum PCT and C reactive protein (CRP) levels within 24 h of admission. Patients were classified into two groups: group 1, alcoholic hepatitis with SIRS alone; group 2, alcoholic hepatitis with SIRS and sepsis. The ability of PCT to predict sepsis was evaluated using receiver-operating characteristic (ROC) analyses to compare the two groups.

RESULTS

The study included 11 patients in group 1 and 29 in group 2. All were male (median age 42 years; range, 24-65 years). Age, dose and duration of alcohol intake, biochemical parameters and median MELD score were not significantly different between the two groups. PCT and CRP were significantly higher among group 2 than group 1 patients (p < 0.05). ROC analysis showed an AUC of 0.81 (95 % CI 0.66-0.96) and 0.83 (95 % CI 0.68-0.93) for PCT and CRP, respectively, in distinguishing sepsis from SIRS without sepsis. A cutoff level of 0.57 mcg/l for PCT (sensitivity 79 %, specificity 82 %) for diagnosing sepsis in patients with alcoholic hepatitis and SIRS was comparable to a serum CRP cutoff level of 2.3 mg/dl (sensitivity 82.0 %, specificity 75 %).

CONCLUSION

Serum PCT can be a useful marker for diagnosing sepsis in patients with alcoholic hepatitis and SIRS and compares favorably with serum CRP levels.

Procalcitonin and C-reactive protein in the diagnosis and prediction of spontaneous bacterial peritonitis associated with chronic severe hepatitis B

Background

Procalcitonin (PCT), C-reactive protein (CRP), and white blood cells (WBCs) are inflammatory markers used to diagnose severe bacterial infections. We evaluated the diagnostic role of these markers and compared their accuracy for spontaneous bacterial peritonitis (SBP) associated with chronic severe hepatitis B (CSHB).

Methods

PCT and CRP concentrations, WBC count, and other hematological parameters were measured in serum from 84 well-characterized patients with CSHB, of whom 42 had SBP. Receiver operating characteristics (ROC) curve analysis was performed to assess the diagnostic accuracy.

Results

PCT and CRP concentrations were significantly higher in the CSHB patients with SBP (n=42) than CSHB patients without SBP (n=42). PCT and CRP concentrations were more accurate than WBC count for the diagnosis of CSHB-associated SBP. The optimal cutoff value of PCT was 0.48 ng/mL. The PCT concentration was significantly correlated with the CRP concentration and WBC count.

Conclusions

Serum PCT and CRP seems to be better markers than WBC for the diagnosis of CSHB patients with SBP.