[Identification of the cutoff value for serum alanine aminotransferase in hepatitis C screening of patients with chronic renal failure on hemodialysis]

Detection of hepatitis C virus in patients with terminal renal disease undergoing dialysis in southern Brazil: prevalence, risk factors, genotypes, and viral load dynamics in hemodialysis patients

Hepatitis C (HCV) is a serious public health issue, and it is estimated that 3% of the world's population is infected. Patients in hemodialysis units have an increased risk for contracting HCV, and high prevalence rates have been found in hemodialysis units around the world. This study is aimed at determining the prevalence of HCV in patients with terminal chronic renal disease (tCRD) who have been submitted to hemodialysis and peritoneal dialysis in southern Brazil to characterize the most prevalent genotypes, the viral load, and possible risk factors and to assess the validity between the ELISA and RT-PCR detection methods. Of 320 patients from three dialysis units, 318 participated in this study. According to the medical records, 55 patients were reactive to HCV, as determined via ELISA. All 318 samples were submitted to RT-PCR and genotyped using an Abbott Realtime m2000 system. Data obtained through a questionnaire and chemical variables were associated with the HCV.

RESULTS

The prevalence of HCV was 18.24% (58), and the concordance between the HCV serology and the RT-PCR was 94%. Three patients were diagnosed to be negative for HCV using the ELISA assay but positive when using RT-PCR. Genotype 1 was the most prevalent (46.7%) genotype, within which subtype 1a was the most frequent (74.1%). One of the risk factors associated with HCV infection was the length of time that the patient had been undergoing hemodialysis treatments (p < 0.001). Additionally, the viral load was found to vary when tested before and after hemodialysis (p < 0.001).

CONCLUSION

The prevalence of HCV in dialysis units continues to remain high, indicating nosocomial contamination. RT-PCR detected the presence of the hepatitis C virus in patients with a non-reactive serology, which highlights the importance of performing molecular tests on dialysis patients. The variation in the viral load in patients submitted to hemodialysis indicates a possible destruction or gripping of viral particles to the dialyzer membrane.

Liver enzymes serum levels in patients with chronic kidney disease on hemodialysis: a comprehensive review

We reviewed the literature regarding the serum levels of the enzymes aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyl transferase in patients with chronic kidney disease on hemodialysis with and without viral hepatitis. Original articles published up to January 2013 on adult patients with chronic kidney disease on hemodialysis were selected. These articles contained the words "transaminases" "aspartate aminotransferase" "alanine aminotransferase" "gamma glutamyl transferase," "liver enzymes", AND "dialysis" OR "hemodialysis". A total of 823 articles were retrieved. After applying the inclusion and exclusion criteria, 49 articles were selected. The patients with chronic kidney disease on hemodialysis had reduced serum levels of aminotransferases due to hemodilution, lower pyridoxine levels, or elevated homocysteine levels. The chronic kidney disease patients on hemodialysis infected with the hepatitis C virus also had lower aminotransferase levels compared with the infected patients without chronic kidney disease. This reduction is in part due to decreased viremia caused by the dialysis method, the production of a hepatocyte growth factor and endogenous interferon-α, and lymphocyte activation, which decreases viral action on hepatocytes. Few studies were retrieved on gamma-glutamyl transferase serum levels; those found reported that there were no differences between the patients with or without chronic kidney disease. The serum aminotransferase levels were lower in the patients with chronic kidney disease on hemodialysis (with or without viral hepatitis) than in the patients with normal renal function; this reduction has a multifactorial origin.

Prevalence and risk factors of hepatitis B and C viruses among haemodialysis patients in Gaza strip, Palestine

Background

The prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) and its associated risk factors among haemodialysis (HD) patients in Gaza strip was investigated using serological and molecular techniques.

Results

The overall prevalence of HBV among the four HD centers was 8.1%. The main risk factors were HD center (p = 0.05), history of blood transfusion (p < 0.01), and treatment abroad (p = 0.01). The overall prevalence of HCV among the four HD centers was 22%. The main risk factors were HD center (p < 0.01), time duration on HD (p < 0.01), history of blood transfusion (p < 0.01), treatment abroad (p < 0.01), and history of blood transfusion abroad (p < 0.01). Serum aminotransferases levels decreased in HD patients compared with normal population but still there was a direct association between the activity of liver enzymes and both HBV (p < 0.01) and HCV (p < 0.01) infection.

Conclusion

The much higher prevalence of Hepatitis viruses among HD patients compared to the normal population of Gaza strip indicates a causative relation between HD and hepatitis viruses transmission. Therefore extremely careful observation of preventive infection control measures is essential to limit Hepatitis viruses' transmission in HD centers.

Infecção pelo vírus da hepatite c em pacientes em hemodiálise: prevalência e fatores de risco

CONTEXTO: Doentes com doença renal crônica em tratamento hemodialítico apresentam risco aumentado de aquisição do vírus da hepatite C (VHC). Elevadas taxas de prevalência têm sido detectadas em unidades de diálise do mundo inteiro. Estudos recentes têm demonstrado que a infecção pelo VHC interfere de forma negativa na sobrevida dos pacientes em hemodiálise e naqueles submetidos ao transplante renal. OBJETIVOS: Determinar a prevalência e os fatores de risco da infecção pelo VHC em pacientes submetidos a hemodiálise. MÉTODOS: Realizou-se estudo transversal entre janeiro e dezembro de 2007. Neste período, 236 pacientes em hemodiálise foram testados pelo ELISA de terceira geração. Os casos positivos foram submetidos a pesquisa qualitativa do HCV-RNA pelo método de PCR. Consideraram-se como portadores de infecção pelo VHC aqueles pacientes com anti-VHC e HCV-RNA positivos. Dosagens mensais de ALT e a média do valor de 12 meses foram obtidas em 195 pacientes. Do total de pacientes, 208 (88,1%) responderam ao questionário padronizado visando a identificação de fatores de risco associados à infecção pelo VHC. RESULTADOS: A prevalência de pacientes anti-VHC positivos encontrada entre os 236 testados foi de 14,8% (35/236); destes, a pesquisa do HCV-RNA foi positiva em 71,6% (25/35). Portanto, a prevalência da infecção crônica pelo VHC foi de 10,6% (25/236) dos pacientes. Pela análise bivariada, os principais fatores de risco associados à infecção pelo VHC foram o tempo de hemodiálise, o número de transfusões de sangue, a realização prévia de diálise peritonial e história de doença sexualmente transmissível. Contudo, após análise multivariada, somente o tempo de hemodiálise e história de doença sexualmente transmissível foram significativamente associados à infecção pelo VHC. Pacientes com mais de 10 anos de hemodiálise apresentaram risco de aquisição do VHC 73,9 (IC de 17,5 a 311,8) vezes maior quando comparados a pacientes com até 5 anos de tratamento. Indivíduos com doença sexualmente transmissível prévia apresentaram risco 4,8 (IC de 1,1 a 19,9) vezes superior de contaminação pelo VHC quando comparados àqueles sem doença sexualmente transmissível. O valor médio da ALT foi significantemente maior nos pacientes infectados pelo VHC (44,0 ± 13,5 U/L versus 33,5 ± 8,0 U/L, P<0,001). CONCLUSÃO: A infecção pelo VHC apresentou elevada prevalência na unidade de diálise analisada. O tempo de tratamento dialítico e história prévia de doença sexualmente transmissível foram os principais fatores de risco associados à infecção pelo VHC. Indivíduos em hemodiálise com infecção crônica pelo VHC apresentaram maior atividade de ALT que pacientes sem hepatite C crônica.

Hepatitis C virus screening and clinical monitoring of biomarkers in patients undergoing hemodialysis

In this study, 395 volunteers were enrolled to investigate the seroprevalence of hepatitis C virus, the immunological and the alanine aminotransferase (ALT) biomarkers amongst hemodialysis patients, living in Manaus, Brazil. An overall seroprevalence of 13.9% was found in the hemodialysis patients. Analysis of seroconversion patterns demonstrated that most patients with HCV seroconverted up to 10 years following the first hemodialysis session. Anti-NS5 antibody was detectable in 60.4% of patients with HCV. A lower percentage of circulating CD3(+) and CD4(+) T-cells was found in patients seronegative for HCV, whereas a higher frequency of CD8(+) T-cells was the hallmark of patients with HCV. An overall low activation state of monocytes and eosinophils were observed in hemodialysis patients. In contrast, a higher frequency of activated neutrophils was observed in patients with HCV, selectively in the NS5+ subgroup. All hemodialysis patients had a higher percentage of activated lymphocytes, with the higher activation state in patients with NS5- reactivity. Higher ALT levels were observed in patients with HCV, especially in the NS5+ subgroup. Interestingly, the ALT levels were correlated negatively with the lymphocyte activation state, selectively in the NS5- subgroup, suggesting a protective role of these activated lymphocytes in patients with HCV. These findings reinforce the importance of the transmission of HCV among hemodialysis patients, suggesting that apart from the HCV screening, the serological and ALT biomarkers may represent important predictors of morbidity and/or mortality among patients undergoing hemodialysis.

Acute hepatitis C virus infection assessment among chronic hemodialysis patients in the Southwest Parana State, Brazil

Background

Chronic hemodialysis patients are at higher risk for acquiring hepatitis C virus (HCV). The prevalence varies among different countries and hemodialysis centers. Although guidelines for a comprehensive infection control program exist, the nosocomial transmission still accounts for the new cases of infection. The aim of this study was analyze the follow up of newly acquired acute hepatitis C cases, during the period from January 2002 to May 2005, in the Hemodialysis Center, located in the Southwest region of Parana State, Brazil and to analyze the effectiveness of the measures to restrain the appearance of new cases of acute hepatitis C.

Methods

Patients were analyzed monthly with anti-HCV tests and ALT measurements. Patients with ALT elevations were monitored for possible acute hepatitis C.

Results

During this period, 32 new cases were identified with acute hepatitis C virus infection. Blood screening showed variable ALT levels preceding the anti-HCV seroconversion. HCV RNA viremia by PCR analysis was intermittently and even negative in some cases. Ten out of 32 patients received 1 mcg/kg dose of pegylated interferon alfa-2b treatment for 24 weeks. All dialysis personnel were re-trained to strictly follow the regulations and recommendations regarding infection control, proper methods to clean and disinfect equipment were reviewed and HCV-positive patients were isolated.

Conclusion

Laboratory tests results showed variable ALT preceding anti-HCV seroconversion and intermittent viremia. The applied recommendations contributed importantly to restrain the appearance of new cases of acute hepatitis C in this center and the last case was diagnosed in May 2004.

Determination of the cut-off value of serum alanine aminotransferase in patients undergoing hemodialysis, to identify biochemical activity in patients with hepatitis C viremia

BACKGROUND

Elevated liver enzymes are infrequent in patients with hepatitis C virus (HCV) infection undergoing chronic hemodialysis (HD), suggesting that the alanine aminotransferase (ALT) is a poor predictor of hepatocellular damage in this population.

OBJECTIVE

To establish a more appropriate cut-off value of ALT to identify biochemical activity due to HCV infection in HD patients.

STUDY DESIGN

A total of 217 patients, with an average age of 51.2 years, were evaluated between January and October 2002; 130 were males (60%). Serum ALT was measured by a kinetic method in five consecutive monthly blood samples, from which an average was obtained and divided by the upper limit of normal (ULN). HCV antibodies were determined using an enzyme immunoassay, the serum HCV-RNA by nested-PCR and HCV genotype by hybridization of the amplified sequence from the 5'-non-coding region. The cut-off value of ALT was obtained from a ROC curve.

RESULTS

Within the 217 patients, 18 (8.3%) were anti-HCV-positive, 17 (7.8%) of whom were also HCV-RNA-positive. Genotype distribution was: 1a=47%; 1b=18%; 3a=35%. Mean ALT/ULN (0.77+/-0.57) of the 18 anti-HCV-positive cases was higher (p<0.001) than the negative group (0.38+/-0.23). The mean ALT/ULN (0.81+/-0.57) of the 17 HCV-RNA-positive cases was also higher (p<0.0001) than the negative cases (0.37+/-0.23). The cut-off value of ALT to distinguish the anti-HCV-positive from negative patients was 0.50% or 50% of the ULN (sensitivity=67%; specificity=83%). According to the HCV-RNA, the cut-off value of ALT was 0.45% or 45% of the ULN (sensitivity=71%; specificity=80%).

CONCLUSION

Reducing the cut-off of ALT by half, enables a better identification of biochemical activity in patients with HCV infection on chronic HD.