ABSTRACT
Objectives:
In this study, it was aimed to investigate the ischemia modified albumin (IMA) and the IMA/albumin ratio (IMAR) and the relationship between these two parameters with fibrosis in patients with chronic hepatitis B (CHB), hepatitis B e antigen negative chronic infection (HBI) and chronic hepatitis C (CHC).
Materials and Methods:
This prospective study included 80 patients with CHB, 50 patients with HBI, 30 patients with CHC and 60 control groups. IMA level was measured using rapid colorimetric analysis developed (albumin-cobalt binding test). IMAR was calculated.
Results:
Forty-two of the CHB cases were female and 38 were male (age range: 46.62±2.69). Thirty of the HBI patients were female and 20 were male (age range: 40.83±3.71). Ten of the cases with CHC were female, and 20 were male (age range: 41.35±3.58). Thirty-three of the control group were female and 27 were male (age range: 30.45±1.08). Serum IMA levels and IMAR, CHB, HBI, and CHC cases were statistically significantly higher than the control group (p<0.05). However, in terms of IMA, IMAR, no statistically significant difference was found in the between CHB, HBI and CHC cases. In CHB and CHC, IMA and IMAR were statistically significantly higher in those with significant fibrosis than those with mild fibrosis (p<0.05).
Conclusion:
IMA and IMAR can be used as a marker in determining prognosis as an indicator of oxidative liver damage and in the evaluation of fibrosis (especially early detection of fibrosis).
Introduction
Chronic liver disease (CLD) is a liver pathology characterized by the gradual destruction of liver tissue over time; hepatitis B virus (HBV) and hepatitis C virus (HCV) viruses are the most common causes of CLD’s morbidity and mortality worldwide (1). In hepatitis B e antigen (HBeAg) negative chronic infection (HBI), despite the risk of developing cirrhosis (LC) and hepatocellular carcinoma (HCC), these complications may not develop throughout their lives (2). Although albumin has many features such as antioxidant activity, and regulation of inflammatory response, it can affect the course of the disease and treatment results quantitatively and qualitatively, and is considered an important and negative prognostic factor (3).
The amino terminal end of the albumin molecule is the primary site for binding metal ions, cobalt and nickel, and under various conditions such as ischemia and oxidative stress (OS), the capacity of albumin to bind metals is reduced. This modified form of albumin, which is formed due to conformational change, is called ischemia modified albumin (IMA). Although IMA is a proven biomarker to increase in various OS-related diseases, the exact mechanism that leads to the formation of IMA is unknown. IMA is shown as a marker of ischemia and OS that occurs as a result of tissue hypoxia (4). In addition, it has been claimed that serum IMA level is associated with disease severity and may have prognostic use in chronic liver failure (5). Evaluation of the degree of necroinflammation and fibrosis in the liver is very important in the treatment decisions and follow-up of the patients (6).
In this study, it was aimed to investigate the importance of IMA and IMA/albumin ratio (IMAR) in diagnosis and determination of prognosis in chronic hepatitis B (CHB), HBI and chronic hepatitis C (CHC) cases and the relationship of these two parameters with fibrosis.
Materials and Methods
Patient Groups
This study is of 80 cases with CHB, 50 cases with HBI, 30 cases with CHC and 60 control group negative for hepatitis B surface antigen, anti-HCV and anti-human immunodeficiency virus, without a history of acute and chronic hepatitis and any chronic disease. Patients under 18 years of age, those with LC and HCC, those with chronic diseases (such as diabetes mellitus, coronary artery disease) were excluded from the study. CHB and CHC cases were divided into two groups as marked fibrosis (stage 3-4) and mild fibrosis (stage 1-2) (there were no stage 5,6).
Determination of Serum IMA Level and IMAR
Approximately 5 cc of blood was taken from the peripheral venous blood from the patients and separated into their serum by centrifugation. Serums were stored at -80 °C in a deep freezer. Serums were brought to room temperature and thawed on the working day. IMA level was measured using a rapid calorimetric analysis based on unbound Co measurement, developed by Bar-Or et al. (7), after incubation with the patient’s serum. This test measures the cobalt binding capacity of albumin in the sample. The absorbances of the test mixtures were measured spectrophotometrically at 470 nm by the albumin-cobalt binding test and the calorimetric method. Results were obtained in about 30 minutes and are reported as absorbance units. In addition, the IMA/IMAR was calculated using the following formula: IMAR=IMA/serum albumin concentration (g/dL).
Biochemical tests of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and albumin were routine analyzes performed in the laboratory with automatic analyzers. Liver biopsy specimens of CHB and CHC cases were scored using the Ishak histological scoring system (fibrosis was evaluated over 6). The study protocol followed the ethical guidelines of the 1975 Helsinki Declaration. Ethics committee approval was obtained from Fırat University Institutional Evaluation Committee (approval number: 24, date: 31.05.2018) and informed consent form was signed by the patients.
Statistical Analysis
Data analysis procedures were carried out using SPSS 22.0 (Chicago, USA) package statistics software. Kolmogorov-Smirnow and Shapiro-Wilk normality analysis was performed to determine the conformity of continuous variables to normal distribution. Student’s t-test was used for the analysis of continuous variables conforming to the normal distribution, and the Kruskal-Wallis test was used for the analysis of variables that did not comply with the normal distribution. Pearson’s chi-square test was used for comparisons between the two groups. Numerical data were expressed as mean ± standard deviation, and categorical data as %. One-Way ANOVA test was used in multiple comparisons. P<0.05 value was considered significant in statistical comparisons.
Results
Forty-two of the CHB cases were female and 38 were male (age range: 46.62±2.69). Thirty of the HBI patients were female and 20 were male (age range: 40.83±3.71). Ten of the cases with CHC were female, and 20 were male (age range: 41.35±3.58). Thirty-three of the control group were female and 27 were male (age range: 30.45±1.08). Serum ALT levels in CHB and CHC were statistically significantly higher than HBI and control groups (p=0.016). The demographic characteristics of CHB, HBI and CHC cases and the control group, the mean and p-values of the laboratory tests are summarized in Table 1.
No statistically significant difference was observed the patients with CHB, HBI, and CHC between serum IMA level and IMAR, and age (p=0.515, p=0.249, respectively) and gender (p=214, p=0.273, respectively). Also, there was no significant difference between IMA and IMAR and AST (p=0.858, p=0.143, respectively), ALT (p=0.539, p=0.326, respectively), AFP (p=0.289, p=0.304, respectively). Serum albumin levels were statistically significantly lower in CHB (3.81±0.04 g/dL), CHC (3.75±0.03 g/dL) and HBI (4.03±0.03 g/dL) than the control group (4.69±0.04 g/dL) (p=0.001). Serum IMA levels and IMAR, CHB, HBI, and CHC were statistically significantly higher than the control group (p=0.004 for IMA, p=0.001 for IMAR, respectively). However, in terms of IMA level and IMAR, no statistically significant difference was found in the comparison between CHB, HBI and CHC cases (p=0.072, p=0.213, respectively). Serum albumin, IMA levels and mean and p-values of IMAR of CHB, HBI, CHC cases and the control group are shown in Table 2.
In CHB and CHC cases, serum albumin levels were statistically significantly lower in those with significant fibrosis than those with mild fibrosis (p=0.044, p=0.012, respectively). Again, IMA and IMAR were statistically significantly higher in those with significant fibrosis than those with mild fibrosis (CHB; p=0.020, p=0.027, CHC, respectively; p=0.007, p=0.012, respectively). Albumin, IMA and IMAR values according to the degree of fibrosis in CHB and CHC cases are shown in Table 3.
Discussion
Hepatitis B and C viruses are two important viruses that cause serious consequences such as LC, fulminant hepatitis and HCC (8,9). Many studies have shown that IMA is the most important isoform of albumin (6,10). It has been reported that IMA concentration does not correlate with age and gender (11). In this study, there was no statistically significant difference between the IMA level and IMAR, and age and gender (p>0.05).
In a study, an increased plasma levels of IMA were observed in CHC cases and it was stated that high IMA concentrations may indicate chronic OS in CHC infection (12). In another study, it has been shown that IMA is not associated with other parameters more specific for the liver and ALT (4). In this study, there was no significant difference between IMA and IMAR and AST, ALT and AFP (p>0.05). Cakir et al. (5) showed that IMA increased in these cases and IMAR was associated with disease severity and liver fibrosis. They stated that as the albumin level decreases in patients with CLD, the IMA level will increase. In another study, it was recommended to use IMAR instead of IMA in patients with advanced liver disease (6).
A change of 1 g/dL in albumin causes a 2.6% change in the IMA level (11). However, the molecular events related to the structural changes that cause the change of serum albumin to IMA have not been fully elucidated (13). In this study, while there was a significant decrease in serum albumin levels in CHB, CHC and HBI compared to the control group, an increase in IMA level was observed (p=0.001). In addition, while there was a significant decrease in serum albumin levels in CHB and CHC compared to the HBI group, an increase in IMA level was found. These findings may be important in terms of demonstrating the importance of ischemia and related OS in liver inflammation due to viral hepatitis.
Another study showed that there is a significant increase in serum IMA levels and IMAR in CLD compared with healthy individuals. In a few cases, IMA has been shown to increase along with other parameters of OS. This suggests that a similar molecular event occurs in chronic hepatitis and that OS and free radical-mediated damage may play an important role in the development of liver failure (4,14). In our study, in line with the results of this study, serum IMA levels and IMAR, in CHB, HBI, CHC were found higher than the control group.
In a study serum IMA and IMAR levels were found to be significantly higher in patients with advanced fibrosis than those with low fibrosis. In addition, it has been stated that IMAR is more valuable than serum IMA concentration in distinguishing cases with mild and advanced fibrosis (6). In this study, serum IMA level and IMAR were significantly higher in those with severe fibrosis than those with mild fibrosis in CHB and CHC cases. This may show that IMA and IMAR can affect disease progression and can be used to evaluate fibrosis. This study is the first study in which serum IMA levels and IMAR values were investigated in cases with HBI according to our literature knowledge.
Study Limitations
There was no patient group with fibrosis 5 and 6 and HCC. The study had a small sample size, especially cases with CHC. Therefore, large-center studies with larger patient numbers are needed.
Conclusion
In this study, IMA levels and IMAR were found to be higher in CHB, HBI and CHC patients compared to the control group. In addition, in those with significant fibrosis in CHB and CHC, IMA level and IMAR were significantly higher than those with mild fibrosis. Early detection of fibrosis is necessary to prevent disease progression and appropriate treatment. IMA, IMAR can be used as a parameters in determining prognosis as an indicator of oxidative liver damage and in the evaluation of fibrosis (especially early detection of fibrosis). Perhaps, treatment methods aimed at preventing the formation of IMA by reducing OS may guide the development of new treatment methods in the future.
Ethics
Ethics Committee Approval: The study protocol followed the ethical guidelines of the 1975 Helsinki Declaration. Ethics committee approval was obtained from Fırat University Institutional Evaluation Committee (approval number: 24, date: 31.05.2018).
Informed Consent: Informed consent form was signed by the patients.
Peer-review: Externally peer-reviewed.
Authorship Contributions
Concept: S.T., Desing: S.T., Data Collection or Processing: A.Ş., Analysis or İnterpretation: A.Ş., Literature Search: A.Ş., Writing: A.Ş., S.T.
Conflict of Interest: No conflict of interest was declared by the authors.
Financial Disclosure: The financial support of the study was provided by the researchers.