Measurement of calprotectin in ascitic fluid to identify elevated polymorphonuclear cell count

Laboratory investigation of peritoneal fluids: an updated practical approach based on the available evidence

Even though analysis of peritoneal fluids (PF) is often requested to medical laboratories for biochemical and morphological tests, there is still no mutual agreement on what the most appropriate way is to manage PF samples and which tests should be appropriately executed. In this update, we tried to identify the most useful tests for PF analysis to establish best practice indications. We performed a literature review and examined available guidelines to select the most appropriate tests by an evidence-based approach. Accordingly, the basic PF profile should include (1) serum to effusion albumin gradient and (2) automated cell counts with differential analysis. This profile allows to determine the PF nature, differentiating between 'high-albumin gradient' and 'low-albumin gradient' effusions, which helps to identify the pathophysiological process causing the ascites formation. Restricted to specific clinical situations, additional tests can be requested as follows: PF lactate dehydrogenase (LDH) and glucose, to exclude (LDH) or confirm (glucose) secondary bacterial peritonitis; PF total protein, to differentiate ascites of cardiac origin from other causes; PF (pancreatic) amylase, for the identification of pancreatic ascites; PF bilirubin, when a choleperitoneum is suspected; PF triglycerides, in differentiating chylous from pseudochylous ascites and PF creatinine, to detect intraperitoneal urinary leakage.

Systematic review of the role of calprotectin in cirrhosis

BACKGROUND

Calprotectin is a calcium-binding-S100-protein synthetized mainly in neutrophils which has been demonstrated to be an accurate biomarker of the presence of these cells. Gut barrier dysfunction in patients with advanced chronic liver disease (ACLD), in addition to the lack of noninvasive tools for diagnosis and prognosis of cirrhosis decompensations, has raised interest in this biomarker.

AIMS

Our aim is to summarize the current evidence regarding the role of calprotectin in terms of its diagnostic and prognostic utility in ACLD.

METHODS

We performed a systematic search (PROSPERO registration no. CRD42023389069) of original articles published without any restrictions on the publication date until January 2023 providing information about calprotectin for the prognosis or diagnosis of ACLD and its decompensations in adult patients.

RESULTS

A total 227 articles were identified, and 26 observational studies finally met the inclusion criteria. In 14 studies, calprotectin was measured in ascitic fluid, all of which reported higher calprotectin values in spontaneous bacterial peritonitis, while cut-off points for its diagnosis were proposed in nine studies. Three studies reported higher faecal calprotectin levels in patients with hepatic encephalopathy and portal hypertension. Four studies evaluated faecal calprotectin and one plasma calprotectin as biomarkers for gut barrier integrity and bacterial translocation.

CONCLUSIONS

Calprotectin is emerging as a promising biomarker in ACLD, particularly for the management of bacterial infections and alcohol-related liver disease. Further research with better study designs should help to determine the feasibility of calprotectin measurement in routine clinical practice.

Ascites fluid calprotectin level is highly accurate in diagnosing spontaneous bacterial peritonitis: a preliminary proof of concept prospective study

Ascites is the most common complication of liver cirrhosis. Spontaneous bacterial peritonitis (SBP) is a common complication of ascites. The diagnosis is made by an ascitic fluid polymorphonuclear (PMN) cell count of ≥ 250/mm3. However, no other diagnostic test is present for the diagnosis of SBP. The aim of the study present study is to assess the diagnostic yield of ascitic calprotectin in SBP, and to explore whether it can predict disease stage. We performed a single center proof-of-concept prospective study including all patients with cirrhosis and ascites who underwent paracentesis. Overall, 31 patients were included in the study. Eight patients had SBP vs. 23 patients without SBP. Ascitic calprotectin level was 77.4 ± 86.5 μg/mL in the SBP group, as compared to 16.1 ± 5.6 μg/mL in the non-SBP group (P = 0.001). An ascitic calprotectin cut-off value of > 21 μg/mL was associated with sensitivity and specificity of 85.7% and 89.5%, respectively, with ROC of 0.947 (95% CI 0.783 to 0.997, P < 0.0001). Notably, ascitic calprotectin did not had a prognostic value in cirrhosis stage and prognosis. Ascitic calprotectin was highly accurate in the diagnosis of SBP. It can be a serve as adjunct for indefinite cases of SBP.

Novel diagnostic markers for periprosthetic joint infection: a systematic review

Background

Identifying novel biomarkers that are both specific and sensitive to periprosthetic joint infection (PJI) has the potential to improve diagnostic accuracy and ultimately enhance patient outcomes. Therefore, the aim of this systematic review is to identify and evaluate the effectiveness of novel biomarkers for the diagnosis of PJI.

Methods

We searched the MEDLINE, EMBASE, PubMed, and Cochrane Library databases from January 1, 2018, to September 30, 2022, using the search terms "periprosthetic joint infection," "prosthetic joint infection," or "periprosthetic infection" as the diagnosis of interest and the target index, combined with the term "marker." We excluded articles that mentioned established biomarkers such as CRP, ESR, Interleukin 6, Alpha defensin, PCT (procalcitonin), and LC (leucocyte cell count). We used the MSIS, ICM, or EBJS criteria for PJI as the reference standard during quality assessment.

Results

We collected 19 studies that analyzed fourteen different novel biomarkers. Proteins were the most commonly analyzed biomarkers (nine studies), followed by molecules (three studies), exosomes (two studies), DNA (two studies), interleukins (one study), and lysosomes (one study). Calprotectin was a frequently analyzed and promising marker. In the scenario where the threshold was set at ≥50-mg/mL, the calprotectin point-of-care (POC) performance showed a high sensitivity of 98.1% and a specificity of 95.7%.

Conclusion

None of the analyzed biomarkers demonstrated outstanding performance compared to the established parameters used for standardized treatment based on established PJI definitions. Further studies are needed to determine the benefit and usefulness of implementing new biomarkers in diagnostic PJI settings.

An evaluation of ascitic calprotectin for diagnosis of ascitic fluid infection in children with cirrhosis

Background

The most common infection in children with the hepatic disease with or without cirrhotic ascites is spontaneous bacterial peritonitis (SBP), which occurs in the absence of an evident intra-abdominal source of infection. The present study aims to assess the value of calprotectin in ascitic fluid in the diagnosis of ascitic fluid infection in children with liver cirrhosis.

Materials and methods

In this cross-section study, 80 children with underlying liver disease who attended the Hepatology and Emergency Department in Shiraz University Hospitals were studied. All the patients were evaluated by a thorough history, clinical examination, laboratory investigations, diagnostic paracentesis with PMNLs count, and Calprotectin, which was measured in 1 mL ascitic fluid by ELISA.

Results

Thirty-five patients (43.75%) were diagnosed with ascitic fluid infection. Of these children 6 cases had positive ascitic fluid culture (SBP). Calprotectin was high in AFI patients with a statistically significant difference in AFI patients compared to non-AFI patients. The cut-off levels were 91.55 mg /L and the area under the curve was 0.971. So it can serve as a sensitive and specific diagnostic test for detection of AFI in children with underlying liver disease.

Conclusion

Elevated ascitic calprotectin levels in cirrhotic patients are a diagnostic and reliable marker for the detection of AFI and are considered a surrogate marker for PMN.

Diagnostic Potential of Calprotectin for Spontaneous Bacterial Peritonitis in Patients Withliver Cirrhosis and Ascites

The development of spontaneous bacterial peritonitis (SBP) is a serious and life-threatening condition in patients with cirrhosis and ascites. The aim of this study was to determine the diagnostic potential of calprotectin in ascites, for SBP in patients with liver cirrhosis and ascites before and after antibiotic treatment and to compare the mean values of calprotectin in ascites in patients with and without SBP. This prospective-observational study was comprised of 70 patients with cirrhosis and ascites, divided into two groups, the SBP and the non-SBP group. Quantitative measurements of calprotectin in ascites was completed with the Quantum Blue Calprotectin Ascites test (LF-ASC25), using the Quantum Blue Reader. The average value of calprotectin in the SBP group was 1.5 ± 0.40 μg / mL, and in the non-SBP group it was lower (0.4 ± 0.30). The difference between the mean values was statistically significant with p <0.05. The mean value of calprotectin in ascites before therapy among the SBP group was 1.5 ± 0.4, and after antibiotic therapy, the value decreased significantly to 1.0 ± 0.6; the difference between the mean values was statistically significant with p <0.05. ROC analysis indicated that calprotectin contributed to the diagnosis of SBP with a 94.3% sensitivity rating (to correctly identify positives), and the specificity was 62.5%, which corresponded to the value of 0.275. Our research confirmed that ascitic calprotectin was a good predictor, and is significantly associated with the occurrence of SBP in patients with liver cirrhosis. By monitoring the value of calprotectin in ascites on the 7th day of antibiotic treatment, the effectiveness of antibiotic treatment in patients with SBP can be determined.

A rapid calprotectin test for the diagnosis of pleural effusion

In previous studies, measuring the levels of calprotectin in patients with pleural effusion (PE) was an exceptionally accurate way to predict malignancy. Here, we evaluated a rapid method for the measurement of calprotectin levels as a useful parameter in the diagnosis of malignant pleural effusion (MPE) in order to minimise invasive diagnostic tests. Calprotectin levels were measured with Quantum Blue^® sCAL (QB^®sCAL) and compared with the gold standard reference ELISA method. Calprotectin levels in patients with benign pleural effusion (BPE) were significantly higher (p < 0.0001) than for MPE patients. We measured the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and positive and negative likelihood ratios (LRs) for a cut-off value of ≤ 14,150 ng/mL; the diagnostic accuracy was 64%. The odds ratio for PE calprotectin levels was 10.938 (95% CI [4.133 − 28.947]). The diagnostic performance of calprotectin concentration was better for predicting MPE compared to other individual parameters. Comparison of two assays showed a slope of 1.084, an intercept of 329.7, and a Pearson correlation coefficient of 0.798. The Bland–Altman test showed a positive bias for the QB^®sCAL method compared to ELISA fCAL^®. Clinical concordance between both these methods was 88.5% with a Cohen kappa index of 0.76 (95% CI [0.68 − 0.84]). We concluded that QB^®sCAL is a fast, reliable, and non-invasive diagnostic tool for diagnosing MPE and represents an alternative to ELISA that could be implemented in medical emergencies.

The Role of Serum Procalcitonin Level as an Early Marker of Ascitic Fluid Infection in Post Hepatitic Cirrhotic Patients

AIMS & BACKGROUND

The early diagnosis of spontaneous bacterial peritonitis (SBP) has been considered important in the overall patient's survival. Ascitic fluid culture examination performance, in the emergency setting, is time-consuming and not always available, so there is a need for easy to apply, rapid and reliable markers for diagnosis of patients with ascites. The present prospective study aimed to determine the early diagnostic value of serum procalcitonin (PCT) levels in decompensated cirrhotic patients (DCPs) with SBP.

METHODS

47 HCV cirrhotic patients with ascites were enrolled for this prospective study. The severity of cirrhosis was classified based on the Child-Pugh criteria. All patients were subjected to paracentesis and ascitic fluid (AF) culture. Serum PCT levels were measured using enzyme-linked fluorescence analysis (ELFA).

RESULTS

The diagnostic value of serum PCT levels and WBC/PLT ratios for detecting infections were serum PCT levels (3.63 ± 3.47 ng/mL) in DCPs with infections which were significantly higher than in DCPs without infections (0.505 ± 0.230 ng/mL); p < 0.05. The cut-off value for serum PCT levels was 0.7 ng/mL for the diagnosis of infections in DCPs, for which the sensitivity and specificity were 93.1% and 73.2%, respectively. The AUC was 0.91 (95% CI: 0.83-0.99).

CONCLUSION

Serum procalcitonin seems to provide satisfactory diagnostic biomarkers in SBP.

The diagnostic accuracy of ascitic calprotectin for the early diagnosis of spontaneous bacterial peritonitis: systematic review and meta-analysis

Spontaneous bacterial peritonitis (SBP) is a common complication in patients with cirrhosis and has an incidence of up to 30% in hospitalized patients. Importantly, it may raise their mortality rate up to 30%. Hence, a delayed diagnosis is associated with poor prognosis. This systematic review aims to assess the diagnostic accuracy of ascitic fluid calprotectin for the early diagnosis of SBP in patients with ascites. This study was conducted in accordance with the PRISMA statement. A systematic literature search was conducted from inception to February 2020 in the following electronic bibliographic databases: MEDLINE, Scopus, The Cochrane Library and OpenGrey. Quality Assessment of Diagnostic Accuracy Studies tool was used to assess risk of bias. Ten studies were included in the qualitative and quantitative synthesis. Hierarchical summary receiver operating characteristic curves were plotted and the summary sensitivity of a positive ascitic fluid calprotectin assessment to detect SBP was 93% [95% confidence interval (CI) 90-95%] while the summary specificity was 89% (95% CI 80-95%), irrespectively of the method used. The positive likelihood ratio and negative likelihood ratio of the test were 8.7 (95% CI 4.4-17.1) and 0.08 (85% CI 0.06-0.12). All studies showed positive correlation between ascitic calprotectin and polymorphonuclear (PMN) leukocyte count. Ascitic calprotectin appears to be an excellent alternative to PMN leucocyte count of ≥250 cells/mm3 for the diagnosis of SBP with much faster time to diagnosis. Owing to its substantially high negative predictive value, the test can accurately exclude SBP avoiding unnecessary antibiotics in suspected patients.

Ascitic Interleukin 6 Is Associated with Poor Outcome and Spontaneous Bacterial Peritonitis: A Validation in Critically Ill Patients with Decompensated Cirrhosis

Decompensated cirrhosis predisposes to infectious diseases and acute-on-chronic liver failure (ACLF) in critically ill patients. Infections like spontaneous bacterial peritonitis (SBP) are frequently associated with multi-organ failure and increased mortality. Consequently, reliable predictors of outcome and early diagnostic markers of infection are needed to improve individualized therapy. This study evaluates the prognostic role of ascitic interleukin 6 in 64 patients with cirrhosis admitted to our intensive care unit (ICU). In addition, we analysed the diagnostic ability of ascitic interleukin 6 in a subgroup of 19 patients with SBP. Baseline ascitic interleukin 6 performed well in predicting 3-month mortality in patients with decompensated cirrhosis (area under curve (AUC) = 0.802), as well as in patients fulfilling ACLF-criteria (AUC = 0.807). Ascitic interleukin 6 showed a moderate prognostic advantage compared with common clinical scores and proinflammatory parameters. Moreover, ascitic interleukin 6 had a sufficient diagnostic ability to detect SBP (AUC = 0.901) and was well correlated with ascitic polymorphonuclear neutrophils in SBP (p = 0.002). Interestingly, ascitic interleukin 6 revealed a high predictive value to rule out apparent infections on admission to ICU (AUC = 0.904) and to identify patients with “culture-positive SBP” (AUC = 0.856). Ascitic interleukin 6 is an easily-applicable proinflammatory biomarker with high prognostic and diagnostic relevance in critically ill patients with liver cirrhosis.

Ascitic calprotectin for the diagnosis of spontaneous bacterial peritonitis: a systematic review and meta-analysis

Calprotectin is a promising diagnostic biomarker for spontaneous bacterial peritonitis (SBP) among cirrhotic patients, but published studies report a wide variation of its diagnostic accuracy. We systematically searched six databases for eligible studies (i.e., all original studies that reported ascitic calprotectin as a diagnostic marker for SBP in cirrhotic patients), and assessed their quality with the Quality Assessment of Diagnostic Accuracy Studies-2 tool. We calculated the pooled sensitivity, specificity, positive and negative likelihood ratios (PLR and NLR), and diagnostic odds ratio (DOR) using the bivariate mixed-effect model. We constructed the summary receiver operating characteristic and determined the area under the curve (AUC). We registered the study protocol in PROSPERO (CRD42019125476). Our search retrieved 102 studies, of which 10 were included in the analysis. The overall risk of bias of these studies ranged from low to moderate. There was no heterogeneity from the threshold effect (Spearman correlation coefficient = 0.100, P value = 0.770). The pooled estimates [95% confidence intervals (CIs)] for ascitic calprotectin were as follows: sensitivity 0.91 (95% CI: 0.88-0.94), specificity 0.87 (95% CI: 0.68-0.96), PLR 7.18 (95% CI: 2.52-20.43), NLR 0.10 (95% CI: 0.07-0.15), DOR 71.91 (95% CI: 19.42-266.34), and AUC 0.92 (95% CI: 0.90-0.94). The sensitivity analysis did not detect outliers, and the model had a robust goodness of fit. There was no significant publication bias detected (Deeks test of asymmetry, P value = 0.79). Ascitic calprotectin is a promising diagnostic biomarker for SBP in cirrhotic patients.

Diagnostic and prognostic role of ascitic fluid calprotectin level: six-month outcome findings in cirrhotic patients

AIM

To assess the role of ascites calprotectin in early detection of SBP in patients with cirrhosis and to investigate its prognostic value in determination of the 6-month outcome. Methods and material: In this cross-sectional study, patients with liver cirrhosis who were consecutively referred to Imam Reza hospital, tertiary referral center in the northwest of Iran, underwent abdominal paracentesis. The samples were collected for measurement of calprotectin, albumin, total protein, WBCs, and PMNs.

RESULTS

The mean age of a total of 87 included patients was 56.86 (SD 16.05) years old with over half of the subjects (55.2%) being female. About 28.7% of performed paracenteses tested positive for SBP. Ascitic calprotectin was positively correlated to the PMN counts. Patients with SBP were found to have higher levels of ascites albumin, total protein, and calprotectin. Only 51 individuals survived the 6-month follow-up period and mortality outcomes were significantly related to the levels of aforementioned biochemical markers (p-value <.05).

CONCLUSION

Alongside with standard PMN counts, calprotectin measurement in the ascitic fluid could be used as an available test for early diagnosis of SBP. Calprotectin can also serve as a valuable prognostic marker in the evaluation of cirrhotic patients.

Ascitic Calprotectin as an early predictor of hepatocellular carcinoma in patients with cirrhotic ascites

BACKGROUND

Calprotectin is a heterodimer formed by S100A8 and S100A9 proteins which are enhanced during hepatic carcinogenesis and the increased expression of both proteins promotes malignant progression of hepatocellular carcinoma. The potential correlation between ascitic Calprotectin and HCC was not studied.

METHODS

100 patients were stratified into a case group which enrolled 50 patients with cirrhotic ascites and documented HCC and a control group consisted of 50 patients with cirrhotic ascites without HCC. They were evaluated by liver function tests, abdominal ultrasound and routine ascitic fluid examination including ascetic Calprotectin and results were validated in another group (n = 100).

RESULTS

Calprotectin level was significantly higher in the HCC group with insignificant difference regarding total cell count, PNLs, ascitic albumin, LDH, CEA and SAAG. It correlated with serum creatinine (r = 0.245, p = 0.014) and number of focal hepatic lesions (r = 0.309, p = 0.002). In the validation group, 28 patients had elevated ascitic Calprotectin of which 21 patients had developed HCC (75%) after a mean period of 3.8 ± 1.54 months. A cut of value 126 ng/ml was accurate to predict HCC in liver cirrhosis with ascites with a sensitivity of 93.3% specificity 94%, AUC 0.950, Youden's J value = 0.873, p = 0.0001.

CONCLUSION

Ascitic Calprotectin may offer an easy, affordable marker that can predict the early occurrence of HCC.

Recurrence of spontaneous bacterial peritonitis in cirrhosis: novel predictors

BACKGROUND AND AIMS

Recurrence of spontaneous bacterial peritonitis (SBP) is still a matter of debate. We conducted this study to evaluate the probable factors that predict the recurrence of SBP in patients who recovered from the first episode of SBP and the long-term outcomes of SBP recurrence.

METHODS

One hundred twenty-four patients diagnosed with liver cirrhosis, SBP and did not receive secondary prophylaxis either with norfloxacin or other antibiotics were included in this prospective cohort pilot study. Clinical, biochemical and ascitic fluid analysis parameters were evaluated. Ascitic fluid interferon-γ-induced protein (IP-10), calprotectin, interleukin-6 and tumor necrosis factor-α were measured by ELISA.

RESULTS

Of these, 76 patients survived with an in-hospital mortality rate of 38.7%. The survivors were classified into two groups according to recurrence and nonrecurrence of SBP and survival time, clinical parameters and cause of death were investigated. Thirty-one participants had one or more attacks of SBP, with a recurrence rate of 40.8% within one-year follow-up. Before discharge, multivariate analysis showed that ascitic IP-10 (≥1220 pg/ml), ascitic calprotectin (≥550 ng/ml), serum albumin (≤2.5 g/dl), nonuse of prophylactic β-blockers and use of proton-pump inhibitors (PPIs) were the independent variables in predicting recurrent SBP. Sepsis-related organ failure was the most common etiology of mortality in the recurrent SBP group within 3 and 6 months.

CONCLUSION

Increased ascitic calprotectin and IP-10, hypoalbuminemia, nonuse of prophylactic β-blockers and use of PPI were independently associated with increased SBP recurrence rate. Sepsis-related organ failure was the most common etiology of mortality.

Role of ascitic endocan levels in the diagnosis of spontaneous bacterial peritonitis in decompensated cirrhosis

Objective: To assess the role of ascitic endocan levels in the diagnosis of spontaneous bacterial peritonitis (SBP) in decompensated cirrhosis.Methods: Ascites samples, as well as demographic and laboratory data, were collected at admission from patients with decompensated cirrhosis. Ascitic endocan, tumour necrosis factor-α (TNF-α), and interleukin-6 (IL-6) levels were measured by ELISA. The influencing factors of SBP, the correlation of ascitic endocan with other inflammatory indicators, and the diagnostic value of ascitic endocan for SBP were analyzed.Results: A total of 167 patients were enrolled, 39 with the SBP group and 128 in the non-SBP group. Ascitic endocan, TNF-α, and IL-6 levels were significantly higher in the SBP group than in the non-SBP group (p < 0.001). Multivariate analysis demonstrated that ascitic endocan was an independent risk factor for SBP [OR = 1.006 (95% CI: 1.002-1.011); p < 0.001]. Endocan was positively correlated with ascites polymorphonuclear leukocytes, TNF-α, and IL-6. ROC curve analysis showed that ascitic endocan had an AUC of 0.805 for the diagnosis of SBP (p < 0.001) and had a sensitivity of 82.1% and specificity of 73.4% when the cut-off value was 295.011 pg/ml.Conclusions: Ascitic endocan level is an independent risk factor and a valuable diagnostic indicator for SBP in decompensated cirrhosis.

Ascitic calprotectin as a useful marker in the diagnosis of spontaneous bacterial peritonitis in adults

Background

Ascitic fluid polymorphonuclear leucocyte count (PMN) is known to be the gold standard for spontaneous bacterial peritonitis (SBP) diagnosis. The aim of this work was to assess ascitic calprotectin for SBP diagnosis. Serum C-reactive protein (CRP), high sensitivity C-reactive protein (hsCRP), nitrous oxide, ascitic PMN, ascitic leucocyte esterase and ascitic calprotectin were measured.

Results

The average age of our patients was 55.25 ± 7.89 years, mostly males (n = 51, 63.8%), anti-HCV antibodies were positive in (n = 61, 76.3%). Sixty-four patients (80%) were Child-Pugh C and their average MELD was 24.29 ± 8.06. Patients with SBP had statistically significant higher median MELD score (26.5 vs. 19) and higher average Child-Pugh score (12.18 ± 1.74 vs. 10.5 ± 1.97). Forty patients had SBP and 40 patients were without SBP. Both the serum and ascitic nitrous oxide did not differ statistically between patients with and without SBP. In contrast, patients with SBP had higher median serum CRP (49 vs. 12 mg/dL), hsCRP (58,000 vs. 23,750 ng/dL) and ascitic calprotectin (7.57 vs. 1.1 ng/mL). The ascitic leucocyte esterase test was positive in 95% of SBP patients in contrast to 2.5% patients without SBP. Ascitic calprotectin >2 ng/mL had 90% sensitivity, 92.5% specificity, 92.3% positive predictive value and 90.2% negative predictive value. MELD, CRP, hsCRP and ascitic calprotectin are independent predictors of SBP.

Conclusion

Ascitic calprotectin is a useful marker for SBP diagnosis.

Serum CD64 and ascitic fluid calprotectin and microRNA-155 as potential biomarkers of spontaneous bacterial peritonitis

AIM

Patients with ascites are at a higher risk for associated of on top bacterial infections with subsequent life-threatening complications. We aimed to evaluate CD64, calprotectin, and microRNA-155 (miR-155) levels as diagnostic markers of spontaneous bacterial peritonitis (SBP) and the effect of using more than one use on the same spot over their diagnostic efficiency.

PATIENTS AND METHODS

An observational comparative study included 103 patients with ascites admitted to the Tropical Medicine Department, Mansoura University Hospital, Egypt, divided into two groups: case group (64 patients) with ascites with SBP and control group (39 patients) with decompensated cirrhotic non-SBP ascites. Twenty milliliters of ascetic fluid was obtained from all participants for bacterial culture, and assessment of calprotectin and miR-155, in addition to 2 ml blood for the CD64 marker expression assay by a flowcytometer.

RESULTS

The sensitivity and specificity of CD64 expression assay were 95.3 and 92.3%, respectively, area under the curve (AUC)=0.93, whereas those of ascetic fluid calprotectin and miR-155 were 87.5 and 82.1%, AUC=0.90 and 95.3 and 97.4%, with AUC of 0.95. Combined blood CD64 and ascetic fluid calprotectin had a diagnostic accuracy of 0.988 for blood CD64 and ascetic fluid miR-155, AUC=0.991, and that for ascetic fluid calprotectin and miR-155 was 0.988. On using the three studied markers together, the diagnostic accuracy was the best recorded, AUC=0.994. P values were less than 0.001.

CONCLUSION

CD64, calprotectin, and miR-155 were good diagnostic markers of SBP and on using this combination, greater efficiency in diagnosis was achieved.

Adjusted Intensive Care Infection Score (ICIS(Δ))-A new approach for prediction of ascitic fluid infection in patients with cirrhosis

BACKGROUND

Early and accurate diagnosis is the key to improving survival in cirrhotic patients with ascitic fluid infection.

AIMS

To investigate the usefulness of adjusted Intensive Care Infection Score (ICIS_Δ) for diagnosis of ascites infection in cirrhotic patients.

METHODS

Cirrhotic patients with ascites (n = 125) were enrolled, and the efficacy of ICIS and ICIS_Δ for predicting ascites infection was evaluated. ICIS_Δ was created by using the weighted variation of each ICIS parameter.

RESULTS

The area under the curves (AUCs) of ICIS for the diagnosis of ascites infection were 0.90 (95% CI: 0.84-0.95), 0.85 (95% CI: 0.79-0.90), and 0.87 (95% CI: 0.81-0.93), for SBP, culture-negative SBP, and combined SBP/culture-negative SBP, respectively. ICIS was optimized and diagnostic accuracy was obviously improved. ICIS_Δ had high AUCs of 0.99 (95% CI: 0.93-1.00) for SBP, 0.98 (95% CI: 0.83-1.00) for culture-negative SBP, and 0.98 (95% CI: 0.94-1.00) for the combination group. The optimal cutoff was identified as ICIS_Δ > 2, which had >97.8% sensitivity and 100% specificity for diagnosis of both SBP and culture-negative SBP. The ICIS_Δ had significantly higher AUCs than PCT and CPR in both groups (P = 0.002-0.008). ICIS_Δ kinetics could differentiate between SBP and culture-negative SBP patients. From sterile ascites, through culture-negative SBP to SBP, three ICIS_Δ parameters showed an increasing trend.

CONCLUSIONS

ICIS and ICIS_Δ are simple, rapid, accurate and cost-effective methods for the diagnosis of ascites infection in cirrhotic patients.

Accuracy of calprotectin using the Quantum Blue Reader for the diagnosis of spontaneous bacterial peritonitis in liver cirrhosis

AIM

We aimed to evaluate the accuracy of the dosage of calprotectin in ascitic fluid (AF) using the Quantum Blue assay, for the prompt diagnosis of spontaneous bacterial peritonitis (SBP).

METHODS

We prospectively collected 236 AF samples from 119 cirrhotic patients hospitalized in two French centers between May 2016 and May 2017. Bloody and chylous/cloudy AF, and secondary peritonitis were excluded. SBP was diagnosed if neutrophils in AF were >250/mm³ using standard cytology. The Quantum Blue Reader selectively measured the calprotectin antigen (MRP8/14) in 12 min within the measurable range from 0.18 to 1.80 μg/mL; values outside this range were registered as 0.17 and 1.81 μg/mL.

RESULTS

A total of 36 AF were considered as SBP (15.2%). SBP had higher median levels of calprotectin than non-SBP (1.81 vs. 0.25 μg/mL, P < 0.001). Calprotectin levels were positively correlated with neutrophils in AF (r = 0.57, P < 0.001) and C-reactive protein (r = 0.43, P < 0.001), but not with the Child-Pugh and Model for End-Stage Liver Disease scores. The optimal threshold of calprotectin to diagnose SBP was set at 1.51 μg/mL (80th percentile of calprotectin), yielding sensitivity, specificity, and positive and negative predictive values of 86.1%, 92.0%, 65.9%, and 97.3%, respectively. Only one asymptomatic patient with SBP had a low calprotectin level, but a high serum C-reactive protein level that strongly suggested an ongoing infection. We also showed that intraclass correlation coefficients for inter- and intra-observer agreement were excellent, with 0.95 and 0.89, respectively.

CONCLUSIONS

The dosage of calprotectin in AF using the Quantum Blue assay is a rapid and reliable method of ruling out SBP in hospitalized cirrhotic patients.

Spontaneous bacterial and fungal peritonitis in patients with liver cirrhosis: A literature review

Spontaneous bacterial (SBP) and spontaneous fungal peritonitis (SFP) can be a life-threatening infection in patients with liver cirrhosis (LC) and ascites. One of the possible mechanisms of developing SBP is bacterial translocation. Although the number of polymorphonuclear cells in the culture of ascitic fluid is diagnostic for SBP, secondary bacterial peritonitis is necessary to exclude. The severity of underlying liver dysfunction is predictive of developing SBP; moreover, renal impairment and infections caused by multidrug-resistant (MDR) organism are associated with a fatal prognosis of SBP. SBP is treated by antimicrobials, but initial empirical treatment may not succeed because of the presence of MDR organisms, particularly in nosocomial infections. Antibiotic prophylaxis is recommended for patients with LC at a high risk of developing SBP, gastrointestinal bleeding, or a previous episode of SBP, but the increase in the risk of developing an infection caused by MDR organisms is a serious concern globally. Less is known about SFP in patients with LC, but the severity of underlying liver dysfunction may increase the hospital mortality. SFP mortality has been reported to be higher than that of SBP partially because the difficulty of early differentiation between SFP and SBP induces delayed antifungal therapy for SFP.

Bacterial translocation markers in liver cirrhosis

Bacterial translocation (BT) is an important mechanism in the development of infection in liver cirrhosis. The migration and colonization of bacteria and/or bacterial products from the bowel to mesenteric lymph nodes is a controlled process in healthy persons. Increased intestinal permeability, bacterial overgrowth and defect of gut-associated lymphatic tissue promote impaired BT in cirrhotics. We reviewed the reports on markers used for the evaluation of BT published between 1987 and 2016. We focused on the clinical consequences of BT in cirrhosis, as indicated by the values of the BT markers. Patients with cirrhosis are reported to have elevated levels of surrogate markers associated with BT compared with controls. The most widely used BT parameters are C-reactive protein, procalcitonin, bacterial DNA, endotoxin or lipopolysaccharide, lipopolysaccharide binding protein, calprotectin, and bactericidal/permeability increasing protein. High levels of these factors in serum and/or ascitic fluid in humans may be associated with advanced liver disease, hemodynamic instability, high levels of proinflammatory cytokines, susceptibility to the development of severe or recurrent infections, acute-on-chronic liver failure, hepatic encephalopathy, hepatorenal syndrome and poor prognosis during follow up. In conclusion, high levels of BT markers are associated with a high inflammatory response, increased complications of liver cirrhosis and occasionally high fatality rates.

Ascitic Fluid Calprotectin and Serum Procalcitonin as Accurate Diagnostic Markers for Spontaneous Bacterial Peritonitis

Background/Aims

The diagnosis of spontaneous bacterial peritonitis (SBP) is based on a polymorphonuclear leukocytes (PMNs) exceeding 250/μL in ascitic fluid. The aim of the study was to evaluate serum procalcitonin and ascitic fluid calprotectin as accurate diagnostic markers for detecting SBP.

Methods

Seventy-nine patients with cirrhotic ascites were included. They were divided into a SBP group, including 52 patients, and a non-SBP group of 27 patients. Serum procalcitonin, ascitic calprotectin, and serum and ascitic levels of tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) were measured using an enzyme-linked immunosorbent assay.

Results

Serum procalcitonin and ascitic calprotectin were significantly higher in SBP patients than in non-SBP patients. Significant increases in both serum and ascitic levels of TNF-α and IL-6 were observed in SBP patients versus non-SBP patients. At a cutoff value of 0.94 ng/mL, serum procalcitonin had 94.3% sensitivity and 91.8% specificity for detecting SBP. In addition, at a cutoff value of 445 ng/mL, ascitic calprotectin had 95.4% sensitivity and 85.2% specificity for detecting SBP. Both were positively correlated with ascitic fluid proteins, PMN count, TNF-α, and IL-6.

Conclusions

According to our findings, determination of serum procalcitonin levels and ascitic calprotectin appears to provide satisfactory diagnostic markers for the diagnosis of SBP.

High serum lipopolysaccharide binding protein is associated with increased mortality in patients with decompensated cirrhosis

BACKGROUND & AIMS

Lipopolysaccharide-binding-protein (LBP) is an acute-phase-protein produced by hepatocytes. Changes in LBP are associated with the dynamics of bacterial translocation and intestinal permeability in decompensated cirrhosis (DC). We assessed serum and ascitic-fluid (AF) LBP and examined their association with mortality in patients with DC.

METHODS

Eighty-eight consecutive patients (73.9% males) underwent thorough diagnostic investigations for infection. LBP (ng/mL) was assessed in serum (N=88) and AF (n=49) by enzyme-linked-immunosorbent-assay and expressed in natural logarithm (ln).

RESULTS

Serum lnLBP was higher in 18 patients with overt infection compared to those without (P<.001). Serum and AF lnLBP 13.49 and 12.11 displayed a very good-negative-predictive value of 90% and 95.1% to rule out infection and spontaneous-bacterial-peritonitis (SBP), respectively. LBP was higher in serum than in AF (P<.001). Serum and AF LBP levels showed a positive correlation with surrogate markers of inflammation. Patients without overt infection were prospectively followed up. The 90-day-mortality rate was 48% and 24.4% in patients with high (≥13.49) and low (<13.49) lnLBP, respectively, (log rank P=0.045). In univariate Cox regression analysis, neutrophils, LBP, MELD score and CRP were predictive of mortality. However, only high LBP (HR 8.1 95%CI 2.0-31.5, P=0.003) and MELD (HR 1.1 95%CI 1.0-1.2, P=0.002) were predictive of mortality in multivariate analysis.

CONCLUSIONS

Serum and AF LBP concentrations showed a high negative-predictive-value to exclude infection and SBP, respectively. High serum LBP was detected in patients without infection at presentation who died during the 90-day-follow-up period. Elevated serum LBP is a marker of short-term mortality in patients without overt bacterial infection.

The ratio of calprotectin to total protein as a diagnostic and prognostic marker for spontaneous bacterial peritonitis in patients with liver cirrhosis and ascites

BACKGROUND

Diagnosis of spontaneous bacterial peritonitis (SBP) is based on a differential ascites leukocyte count which does not provide prognostic information. We performed a pilot study to assess calprotectin in ascites as an alternative diagnostic and prognostic marker.

METHODS

We collected ascites from patients with liver cirrhosis from March 2012 to July 2013. Routine clinical and laboratory data of the patients were recorded. Ascites calprotectin levels were determined by ELISA.

RESULTS

Overall, we collected 120 ascites samples from 100 patients with liver cirrhosis and from eight patients with malignant peritoneal effusion as disease control. Samples without infection had significantly lower calprotectin levels (median 34 ng/mL, range 5-795) than SBP samples (median 928 ng/mL, range 21-110,480; p<0.001) and malignant effusions (median 401, range 47-2596 ng/mL; p<0.001). In non-infected ascites, calprotectin levels were higher in Child-Pugh stage B versus C (median 57 ng/mL vs. 17 ng/mL; p<0.001) and in alcoholic versus viral cirrhosis (median 37 ng/mL vs. 10 ng/mL; p=0.015). The ratio of ascites calprotectin to total protein was a better marker for SBP than calprotectin alone (AUROC=0.93; p<0.001; sensitivity 93%, specificity 79%; positive predictive value 60%; negative predictive value 97%). In addition, high levels of the ratio to total protein were associated with poor 30-day survival (p=0.042).

CONCLUSIONS

The ratio of ascites calprotectin to total protein may be a promising new diagnostic and prognostic marker in patients with liver cirrhosis and SBP and should be evaluated further.

Ascitic Calprotectin is a Novel and Accurate Marker for Spontaneous Bacterial Peritonitis

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is a known complication of advanced cirrhosis and presents a high mortality rate. A polymorphonuclear (PMN) cell count >250/μl in the ascitic fluid is the current gold standard for diagnosing SBP.

AIM

We evaluated the accuracy of a point-of-care test (POCT) for ascitic calprotectin in diagnosing patients with SBP.

METHODS

Eighty-eight patients admitted with decompensation of liver cirrhosis were studied including 41 patients (46.6%) with SBP. Ascitic calprotectin was measured using a quantitative POCT developed by Bühlmann^® .

RESULTS

Calprotectin levels correlated with PMN cell count and other inflammatory markers and were significantly higher in patients with SBP. An optimal cutoff of calprotectin above 1.57 μg/ml presented high sensitivity (87.8%), specificity (97.9%), and positive (97.3%) and negative (90.2%) predictive values for diagnosing SBP. Using calprotectin selectively in patients with a serum albumin-ascites gradient above 11 g/l further increased the sensitivity and negative predictive values of the test.

CONCLUSION

Ascitic calprotectin appears to be a reliable method for diagnosing SBP in patients with liver cirrhosis. It may present an alternative to other conventional diagnostic methods.

Evaluation of Biliary Calprotectin as a Biomarker in Primary Sclerosing Cholangitis

Primary sclerosing cholangitis (PSC) is a chronic inflammatory disease of the bile ducts with limited therapeutic options except liver transplantation. Reliable biomarkers to predict the disease course are unavailable, and currently employed disease activity scores such as the Mayo risk score (MRS) have limitations. The present study aims to evaluate biliary calprotectin as a marker of disease activity and prognosis in PSC.This is a monocentric retrospective observational study. Calprotectin concentrations were measured by an enzyme-linked immunosorbent assay in bile samples collected by endoscopic retrograde cholangiography from 106 PSC patients and 20 controls. Biliary calprotectin concentrations were compared between the 2 groups. In PSC patients, results were evaluated with regard to the presence of dominant bile duct stenoses, bile microbiology, MRS, survival free of liver transplantation, and necessity for bile duct interventions in the further disease course.Median (interquartile ranges) biliary calprotectin concentrations were higher in PSC patients than in controls (3646 ng/mL, 249-9748 vs 116 ng/mL, 104-655; P < 0.001). In the PSC cohort, higher biliary calprotectin concentrations were associated with the presence of microbes in bile (P = 0.02), the occurrence of dominant bile duct stenosis at any time in the disease course (P = 0.005), and the necessity for future bile duct interventions (P = 0.02). Patients with biliary calprotectin concentrations above a cut-off of 11,610 ng/mL displayed significantly shorter transplantation-free survival than those with biliary calprotectin concentrations ≤11,610 ng/mL (P < 0.001). Univariate Cox regression analysis revealed high biliary calprotectin concentration (>11,610 ng/mL) as a risk factor of shorter transplantation-free survival of PSC patients (P < 0.001) beside high plasma alkaline phosphatase (ALP) concentration (>142.5 U/L) (P = 0.006), high MRS (≥2) (P < 0.001), and nonsterility of bile (P = 0.03). Multivariate analysis identified only MRS (P = 0.002) and ALP concentration (P = 0.04) as independent risk factors.Our data strongly suggest that biliary calprotectin may be a valuable additional marker for disease activity and a predictor of outcome in PSC, so that further studies for evaluation of calprotectin in this disease are warranted.

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.

Spontaneous bacterial peritonitis: The clinical challenge of a leaky gut and a cirrhotic liver

Spontaneous bacterial peritonitis (SBP) is a frequent, life-threatening bacterial infection in patients with liver cirrhosis and ascites. Portal hypertension leads to increased bacterial translocation from the intestine. Failure to eliminate invading pathogens due to immune defects associated with advanced liver disease on the background of genetic predisposition may result in SBP. The efficacy of antibiotic treatment and prophylaxis has declined due to the spread of multi-resistant bacteria. Patients with nosocomial SBP and with prior antibiotic treatment are at a particularly high risk for infection with resistant bacteria. Therefore, it is important to adapt empirical treatment to these risk factors and to the local resistance profile. Rifaximin, an oral, non-absorbable antibiotic, has been proposed to prevent SBP, but may be useful only in a subset of patients. Since novel antibiotic classes are lacking, we have to develop prophylactic strategies which do not induce bacterial resistance. Farnesoid X receptor agonists may be a candidate, but so far, clinical studies are not available. New diagnostic tests which can be carried out quickly at the patient’s site and provide additional prognostic information would be helpful. Furthermore, we need tools to predict antibiotic resistance in order to tailor first-line antibiotic treatment of spontaneous bacterial peritonitis to the individual patient and to reduce mortality.