New chemiluminescent enzyme immunoassay for quantitative measurement of Mac-2 binding protein glycosylation isomer in chronic liver disease

BACKGROUND

This study aimed to evaluate the quantitative measurement of Mac-2 binding protein glycosylation isomer (M2BPGi) levels using the new chemiluminescent enzyme immunoassay.

METHODS

The data of a total of 347 patients with hepatitis C virus (HCV) infection and 150 health volunteers from 13 locations in Japan were evaluated. The quantitative system for measuring M2BPGi-Qt levels was based on a new chemiluminescent enzyme immunoassay. We evaluated the reproducibility and quantitation range in quantitative M2BPGi-Qt measurement. We also investigated the confidence ratio of M2BPGi-Qt levels measured by the new quantitative system to M2BPGi levels measured by the current semi-quantitative system for validating the clinical utility of the new method.

RESULTS

The reproducibility of M2BPGi-Qt in HCV samples with negative, positive 1+, and positive 2+ was 0.77 ± 0.02 AU/mL, 2.25 ± 0.03 AU/mL, and 6.55 ± 0.21 AU/mL, respectively, and the corresponding coefficient of variation (CV)s were 2.1%, 1.3%, and 3.2%, respectively. The range of quantification assessment resulted that all CVs showed less than 5% in investigated range. Sample stability testing found that the mean percentage difference between the pre- and post-storage values of 6 samples ranged between 96.2 and 103.9%. The correlation coefficient between M2BPGi and M2BPGi-Qt in patients with HCV and the healthy volunteers was 0.986 and 0.991, respectively. M2BPGi-Qt could be quantitatively assessed in a patient with over 20 C.O.I.

CONCLUSION

Compared with qualitative methods, the M2BPGi quantitative measurement system could provide a numerical value unaffected by interpretation bias, and measurements are more precise at high M2BPGi levels.

Association Between Serum Hemoglobin Levels and Non Alcoholic Fatty Liver Disease in a Mexican Population

INTRODUCTION AND AIM

Nonalcoholic fatty liver disease (NAFLD) is closely associated with overweight and obesity, becoming one of the most prevalent hepatic diseases nowadays. Circulating hemoglobin (Hb) concentration is significantly higher in people with NAFLD, compared to healthy patients. While liver biopsy remains the gold standard for NAFLD diagnosis, it is not the best technique due to adverse events that may occur. Therefore it is important to find less invasive and more sensitive markers. This study aimed to determine the association of serum Hb levels in patients with steatosis and fibrosis as a noninvasive marker.

MATERIAL AND METHODS

A 1,186 patient cross-sectional study nested in a randomized clinical trial (NCT01874249) was conducted. Patients were diagnosed by ultrasound for hepatic steatosis and fibroscan for fibrosis; blood test and anthropometric measurements were also assessed.

RESULTS

Serum Hb increased proportionally related to the steatosis level, being significantly higher in patients with severe steatosis than in patients with moderate and mild steatosis.

CONCLUSION

Patients with non-alcoholic fatty liver disease showed elevated levels of circulating Hb, evidence that suggests that Hb exerts a protective role, as it may act as an antioxidant and may counteract the adverse effects of this disease.

Role of assessing liver fibrosis in management of chronic hepatitis C virus infection

Fibrosis progression is common in hepatitis C. Both host and viral factors influence its natural history. Liver fibrosis is a key predictive factor for advanced disease including endpoints such as liver failure, cirrhosis and hepatocellular carcinoma (HCC). METAVIR fibrosis stages F3-F4 have been considered as the threshold for antiviral therapy. However, this aspect is controversial after the advent of new direct-acting antivirals (DAAs) because they show an excellent efficacy and safety profile. Moreover, in the DAA era, fibrosis stage seems not to be a predictive factor of a sustained virological response (SVR). Viral eradication decreases liver damage by improving the inflammation, as well as by regressing fibrosis irrespective of the treatment regimen. Non-invasive methods are useful in the assessment of liver fibrosis, replacing liver biopsy in clinical practice; but their usefulness for monitoring fibrosis after SVR needs to be demonstrated. Fibrosis regression has been demonstrated after the eradication of hepatitis C virus infection and is associated with a lower risk of hepatic cirrhosis and liver cancer. However, patients showing advanced fibrosis and cirrhosis must be followed-up after SVR, as risks of portal hypertension and HCC remain.

Proteomics for rejection diagnosis in renal transplant patients: Where are we now?

Rejection is one of the key factors that determine the long-term allograft function and survival in renal transplant patients. Reliable and timely diagnosis is important to treat rejection as early as possible. Allograft biopsies are not suitable for continuous monitoring of rejection. Thus, there is an unmet need for non-invasive methods to diagnose acute and chronic rejection. Proteomics in urine and blood samples has been explored for this purpose in 29 studies conducted since 2003. This review describes the different proteomic approaches and summarizes the results from the studies that examined proteomics for the rejection diagnoses. The potential limitations and open questions in establishing proteomic markers for rejection are discussed, including ongoing trials and future challenges to this topic.

Factors associated with the platelet count in patients with chronic hepatitis C

BACKGROUND

There are many potential causes of thrombocytopenia in patients with chronic hepatitis C (CHC).

AIMS

We sought to determine the association between thrombopoietin (TPO) level, immature platelet fraction (IPF), immunoglobulin G (IgG) level, spleen size, and the platelet count in CHC.

METHODS

We studied a consecutive sample of patients enrolled in an observational study at a referral-based research center, excluding subjects based on eligibility criteria. TPO, glycocalicin, and von Willebrand Factor (vWF) levels were determined using stored sera. Hepatic fibrosis was assessed via transient elastography (TE) when available, and clinical laboratory values and radiologic data were obtained from the medical record. We performed analyses of the relationships between independent variables and the platelet count.

RESULTS

On univariate analysis, the following variables were significantly associated with the platelet count: age, alanine aminotransferase (ALT), direct bilirubin, total bilirubin, IPF, international normalized ratio (INR), spleen size, vWF, glycocalicin, fibrosis stage on liver biopsy, and TE (P-values all <0.05). A multivariable model determined that imputed TE score, TPO, IPF, and spleen size were independently associated with the platelet count (P-values all<0.05).

CONCLUSIONS

The platelet count in CHC is significantly associated with fibrosis, TPO level, IPF, and spleen size. Our findings challenge the proposed mechanism of decreased TPO levels or decreased bone marrow production of platelets as a cause of thrombocytopenia in CHC. Future studies focusing on the effects of fibrosis and splenomegaly on platelets may shed more light on the pathophysiology of thrombocytopenia in patients with CHC.

Analysis of discordance between transient elastography and liver biopsy for assessing liver fibrosis in chronic hepatitis B virus infection

BACKGROUND

Transient elastography (TE) is used to assess liver fibrosis in chronic hepatitis B virus (CHBV) infection. However, factors affecting liver stiffness (LS) values and discordance between TE and liver biopsy in CHBV infection remain to be evaluated.

AIM

The aim is to define the optimal cutoff values of LS for significant fibrosis (≥F2) and cirrhosis (F4) and to study the clinical and histological variables associated with LS values and discordance between TE and liver biopsy in assessing liver fibrosis in CHBV-infected subjects.

METHODS

Patients with CHBV infection (n = 200; 159 male; age 37.6 ± 3.7 years) underwent liver biopsy concomitantly with TE. Liver biopsy was scored for activity (Ishak score), fibrosis (METAVIR score), steatosis, cholestasis, and congestion. Hepatic fibrosis percentage was estimated by morphometry.

RESULTS

Liver stiffness values were significantly correlated with histological activity index (HAI) score, F score, and fibrosis percentage. Optimal cutoff values for prediction of significant fibrosis and cirrhosis were 7.05 kPa [sensitivity 81.2 %; specificity 74 %; area under the receiver operating characteristic curve (AUROC) 0.850] and 10.85 kPa (sensitivity 87 %; specificity 85.3 %; AUROC 0.907), respectively. A total of 47 (23.5 %) [overestimation of actual fibrosis by TE, 34 (17 %); underestimation, 13 (6.5 %)] and 28 (14 %) [overestimation, 25 (12.5 %); underestimation, 3 (1.5 %)] patients showed discrepant results for diagnosis of significant fibrosis and cirrhosis, respectively. HAI and interquartile range (IQR) were the factors predictive of overestimation in cirrhosis.

CONCLUSIONS

Fibrosis and necroinflammatory activity are the main determinants of TE in CHBV infection. Overestimation of actual fibrosis stage by TE is common and is influenced by necroinflammatory activity and IQR for estimation of cirrhosis.

Sequential algorithms combining non-invasive markers and biopsy for the assessment of liver fibrosis in chronic hepatitis B

AIM: To assess the performance of several non-invasive markers and of our recently proposed stepwise combination algorithms to diagnose significant fibrosis (F ≥ 2 by METAVIR) and cirrhosis (F4 by METAVIR) in chronic hepatitis B (CHB).

METHODS: One hundred and ten consecutive patients (80 males, 30 females, mean age: 42.6 ± 11.3) with CHB undergoing diagnostic liver biopsy were included. AST-to-Platelet ratio (APRI), Forns’ index, AST-to-ALT Ratio, Goteborg University Cirrhosis Index (GUCI), Hui’s model and Fibrotest were measured on the day of liver biopsy. The performance of these methods and of sequential algorithms combining Fibrotest, APRI and biopsy was defined by positive (PPV) and negative (NPV) predictive values, accuracy and area under the curve (AUC).

RESULTS: PPV for significant fibrosis was excellent (100%) with Forns and high (> 92%) with APRI, GUCI, Fibrotest and Hui. However, significant fibrosis could not be excluded by any marker (NPV < 65%). Fibrotest had the best PPV and NPV for cirrhosis (87% and 90%, respectively). Fibrotest showed the best AUC for both significant fibrosis and cirrhosis (0.85 and 0.76, respectively). Stepwise combination algorithms of APRI, Fibrotest and biopsy showed excellent performance (0.96 AUC, 100% NPV) for significant fibrosis and 0.95 AUC, 98% NPV for cirrhosis, with 50%-80% reduced need for liver biopsy.

CONCLUSION: In CHB sequential combination of APRI, Fibrotest and liver biopsy greatly improves the diagnostic performance of the single non-invasive markers. Need for liver biopsy is reduced by 50%-80% but cannot be completely avoided. Non-invasive markers and biopsy should be considered as agonists and not antagonists towards the common goal of estimating liver fibrosis.