RESUMO
Interleukin-10 (IL-10) is a cytokine that plays an important role in the regulation of the immune system. Gene polymorphisms of IL-10 have been associated with the different expression levels of this cytokine. In hepatitis C virus infection, IL-10 appears to interfere with the progression of disease, viral persistence and the response to therapy. This study investigated genetic variability in the IL-10 gene promoter between patients infected with hepatitis C virus (HCV) and healthy individuals, associating the frequency of polymorphisms with different aspects of viral infection. This is a case-control study with 260 patients who were infected with HCV and 260 healthy individuals. Genotyping of the polymorphisms was performed using the technique of amplification refractory mutation system PCR (ARMS-PCR) for regions of the IL-10 gene promoter (-1082 G/A, -819 C/T, -592 C/A). The frequencies of alleles and genotypes related to polymorphisms in the IL-10 gene promoter showed a higher frequency of the G allele and genotype GG in the -1082 region between the infected group and the control group (p=0.005 and p=0.001, respectively), whereas the AA genotype was significantly more frequent in the control group. The frequencies of the haplotypes GTA and GCC were higher in the group of infected individuals, whereas the haplotype ATA was more frequent in the healthy group (p<0.006). It was also observed that the genotypes GG and AG in the region -1082 were significantly more frequent among patients infected with HCV who were in advanced stages of fibrosis and cirrhosis (p=0.042). No association was observed between polymorphisms of IL-10 and sustained virologic response (SVR).
Assuntos
Antivirais/uso terapêutico , Predisposição Genética para Doença , Hepacivirus/fisiologia , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Interleucina-10/genética , Polimorfismo de Nucleotídeo Único/genética , Alelos , Antivirais/farmacologia , Brasil , Estudos de Casos e Controles , Demografia , Feminino , Frequência do Gene , Haplótipos/genética , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/virologia , Humanos , Inflamação/genética , Cirrose Hepática/genética , Masculino , Pessoa de Meia-Idade , Regiões Promotoras GenéticasRESUMO
UNLABELLED: 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.
Assuntos
Hepacivirus/isolamento & purificação , Hepatite C/epidemiologia , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Diálise Peritoneal/efeitos adversos , Diálise Renal/efeitos adversos , Carga Viral , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Infecção Hospitalar/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Anticorpos Anti-Hepatite C/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , RNA Viral/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de RiscoRESUMO
BACKGROUND: Hepatitis C virus infection is a serious public health problem. Hemodialysis is considered one of the main risk factors of HCV infection, due to several invasive medical procedures and potential nosocomial transmission that patients with chronic renal failure (CRF) are continuously submitted. The aims of this study were to determine the prevalence of HCV and its genotypes in patients with CRF in hemodialysis units in southern Brazil. METHODS: Demographic data and risk factors for HCV transmission were collected and analyzed. These data were obtained from patients undergoing hemodialysis treatment from January 2009 to August 2010, on two dialysis units of Rio Grande, southern Brazil. Genotyping was carried out by sequencing analysis of HCV NS5b, core-E1 junction and 5'UTR genomic regions. RESULTS: One hundred fifty-nine patients under regular hemodialysis treatment were studied. HCV prevalence was 23.3%. HCV-infected patients had been on dialysis treatment for 91.9 months, a more prolonged period compared to HCV-negative patients (p = 0.001). While HCV genotypes 1b and 3a were identified as the most frequent strains, a surprisingly high proportion of genotype 2b was observed among patients in one of the dialysis centers compared to the general HCV-infected population of the same area. Hemodialysis treatment exposure time and healthcare working were associated with HCV infection. CONCLUSIONS: Besides the efforts to minimize nosocomial transmission of HCV, some events of transmission are still evidenced in dialysis units.