Aspartate Aminotransferase and Alanine Aminotransferase Levels in Hemodialysis Patients With Positive Hepatitis B/Hepatitis C Serology: Are They Good Predictors of Liver Injury?

Abstract

IntroductionThe annual United States health care expenditure due to hepatitis B and hepatitis C infection total more than $1 billion. Hemodialysis (HD) patients constitute a large fraction of the infected population. Previous studies reveal a prevalence of 1% of HD patients to be seropositive for hepatitis B virus (HBV) and 7.8% for hepatitis C virus (HCV). Transaminases, including aspartate aminotransferase (AST) and alanine aminotransferase (ALT), have been found to be low in the serum of end-stage renal disease (ESRD)/Dialysis patients. The exact cause of low serum ALT and AST in HD patients is not known. A possible explanation for the decreased AST and ALT may be due to subnormal serum levels of pyridoxal-5-phosphate (PLP), active form of B6 which serves as co-enzymes for transaminases. The aim of this study is to investigate the effect of positive HBV/HCV serology on the serum levels of AST and ALT in HD patients.Materials and MethodsA total of 120 patients were selected for this retrospective case control study. Cases were stratified using the Apache-II score. All patients were diagnosed with ESRD/HD and were separated into two groups of 63 patients and 57 patients classified as ESRD/HD patients with HBV/HCV infection and ESRD/HD patients without infection, respectively. Patients with liver cirrhosis and other possible causes for serum aminotransaminase elevation were excluded from the study. Serological testing was used to determine the patients' hepatitis infection status. Patient records were further studied for clinical data.ResultsA total of 63 patients were placed in a group classified as ESRD/HD with HBV/HCV infection. The mean age for the group was 58.90 ± 14.02 years. The following results were collected: BUN: 52.73 ± 28.46 mg/dL,Creatinine: 6.66 ± 2.76 mg/dL,AST: 32.04 ± 20.03 IU/L,ALT: 22.09 ± 16.31 IU/L A total of 57 patients were placed in a group classified as ESRD/HD with no HBV/HCV infection. The mean age for the group was 56.75 ± 16.83 years. The following results were collected:BUN: 60.45 ± 31.10 mg/dL, Creatinine: 7.31 ± 4.15 mg/dL, AST: 28.47 ± 14.95 IU/L, ALT: 19.65 ± 10.20 IU/L. The data was analyzed separately using the paired Student t test. The result showed insignificant P values for the difference in AST values (P = .27) and ALT values (P = .33) in the two groups.ConclusionThe results of this study suggest that AST and ALT may not be good indicators of liver injury in ESRD patients undergoing hemodialysis due to the deficiency of pyridoxine leading to impaired enzyme synthesis and/or due to the effect of uremic serum. Interestingly, we did not find a negative correlation between the transaminases and level of uremia/ elevated creatinine levels as opposed to some other studies. Our study is limited, because all patients studied were selected based on a positive serological result. Tissue biopsy was not performed to confirm the presence of active hepatitis. Further studies are warranted with patients confirmed by histological exam. IntroductionThe annual United States health care expenditure due to hepatitis B and hepatitis C infection total more than $1 billion. Hemodialysis (HD) patients constitute a large fraction of the infected population. Previous studies reveal a prevalence of 1% of HD patients to be seropositive for hepatitis B virus (HBV) and 7.8% for hepatitis C virus (HCV). Transaminases, including aspartate aminotransferase (AST) and alanine aminotransferase (ALT), have been found to be low in the serum of end-stage renal disease (ESRD)/Dialysis patients. The exact cause of low serum ALT and AST in HD patients is not known. A possible explanation for the decreased AST and ALT may be due to subnormal serum levels of pyridoxal-5-phosphate (PLP), active form of B6 which serves as co-enzymes for transaminases. The aim of this study is to investigate the effect of positive HBV/HCV serology on the serum levels of AST and ALT in HD patients. The annual United States health care expenditure due to hepatitis B and hepatitis C infection total more than $1 billion. Hemodialysis (HD) patients constitute a large fraction of the infected population. Previous studies reveal a prevalence of 1% of HD patients to be seropositive for hepatitis B virus (HBV) and 7.8% for hepatitis C virus (HCV). Transaminases, including aspartate aminotransferase (AST) and alanine aminotransferase (ALT), have been found to be low in the serum of end-stage renal disease (ESRD)/Dialysis patients. The exact cause of low serum ALT and AST in HD patients is not known. A possible explanation for the decreased AST and ALT may be due to subnormal serum levels of pyridoxal-5-phosphate (PLP), active form of B6 which serves as co-enzymes for transaminases. The aim of this study is to investigate the effect of positive HBV/HCV serology on the serum levels of AST and ALT in HD patients. Materials and MethodsA total of 120 patients were selected for this retrospective case control study. Cases were stratified using the Apache-II score. All patients were diagnosed with ESRD/HD and were separated into two groups of 63 patients and 57 patients classified as ESRD/HD patients with HBV/HCV infection and ESRD/HD patients without infection, respectively. Patients with liver cirrhosis and other possible causes for serum aminotransaminase elevation were excluded from the study. Serological testing was used to determine the patients' hepatitis infection status. Patient records were further studied for clinical data. A total of 120 patients were selected for this retrospective case control study. Cases were stratified using the Apache-II score. All patients were diagnosed with ESRD/HD and were separated into two groups of 63 patients and 57 patients classified as ESRD/HD patients with HBV/HCV infection and ESRD/HD patients without infection, respectively. Patients with liver cirrhosis and other possible causes for serum aminotransaminase elevation were excluded from the study. Serological testing was used to determine the patients' hepatitis infection status. Patient records were further studied for clinical data. ResultsA total of 63 patients were placed in a group classified as ESRD/HD with HBV/HCV infection. The mean age for the group was 58.90 ± 14.02 years. The following results were collected: BUN: 52.73 ± 28.46 mg/dL,Creatinine: 6.66 ± 2.76 mg/dL,AST: 32.04 ± 20.03 IU/L,ALT: 22.09 ± 16.31 IU/L A total of 57 patients were placed in a group classified as ESRD/HD with no HBV/HCV infection. The mean age for the group was 56.75 ± 16.83 years. The following results were collected:BUN: 60.45 ± 31.10 mg/dL, Creatinine: 7.31 ± 4.15 mg/dL, AST: 28.47 ± 14.95 IU/L, ALT: 19.65 ± 10.20 IU/L. The data was analyzed separately using the paired Student t test. The result showed insignificant P values for the difference in AST values (P = .27) and ALT values (P = .33) in the two groups. A total of 63 patients were placed in a group classified as ESRD/HD with HBV/HCV infection. The mean age for the group was 58.90 ± 14.02 years. The following results were collected: BUN: 52.73 ± 28.46 mg/dL,Creatinine: 6.66 ± 2.76 mg/dL,AST: 32.04 ± 20.03 IU/L,ALT: 22.09 ± 16.31 IU/L A total of 57 patients were placed in a group classified as ESRD/HD with no HBV/HCV infection. The mean age for the group was 56.75 ± 16.83 years. The following results were collected:BUN: 60.45 ± 31.10 mg/dL, Creatinine: 7.31 ± 4.15 mg/dL, AST: 28.47 ± 14.95 IU/L, ALT: 19.65 ± 10.20 IU/L. The data was analyzed separately using the paired Student t test. The result showed insignificant P values for the difference in AST values (P = .27) and ALT values (P = .33) in the two groups. ConclusionThe results of this study suggest that AST and ALT may not be good indicators of liver injury in ESRD patients undergoing hemodialysis due to the deficiency of pyridoxine leading to impaired enzyme synthesis and/or due to the effect of uremic serum. Interestingly, we did not find a negative correlation between the transaminases and level of uremia/ elevated creatinine levels as opposed to some other studies. Our study is limited, because all patients studied were selected based on a positive serological result. Tissue biopsy was not performed to confirm the presence of active hepatitis. Further studies are warranted with patients confirmed by histological exam. The results of this study suggest that AST and ALT may not be good indicators of liver injury in ESRD patients undergoing hemodialysis due to the deficiency of pyridoxine leading to impaired enzyme synthesis and/or due to the effect of uremic serum. Interestingly, we did not find a negative correlation between the transaminases and level of uremia/ elevated creatinine levels as opposed to some other studies. Our study is limited, because all patients studied were selected based on a positive serological result. Tissue biopsy was not performed to confirm the presence of active hepatitis. Further studies are warranted with patients confirmed by histological exam.