[Hepatitis C serum prevalence in hemodialyzed patients]

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.

Association of killer cell immunoglobulin-like receptor polymorphisms with chronic hepatitis C and responses to therapy in Brazil

Soroprevalence for Hepatitis C virus is reported as 2.12% in Northern Brazil, with about 50% of the patients exhibiting a sustained virological response (SVR). Aiming to associate polymorphisms in Killer Cell Immunoglobulin-like Receptors (KIR) with chronic hepatitis C and therapy responses we investigated 125 chronic patients and 345 controls. Additionally, 48 ancestry markers were genotyped to control for population stratification. The frequency of the KIR2DL2 and KIR2DL2+HLA-C^Asp80 gene and ligand was higher in chronic infected patients than in controls (p < 0.0009, OR = 3.4; p = 0.001, OR = 3.45). In fact, KIR2DL3 is a weaker inhibitor of NK activity than KIR2DL2, which could explain the association of KIR2DL2 with chronic infection. Moreover, KIR2DS2 and KIR2DS2+HLA-C^Asp80 (p < 0.0001, OR = 2.51; p = 0.0084, OR = 2.62) and KIR2DS3 (p < 0.0001; OR = 2.57) were associated with chronic infection, independently from KIR2DL2. No differences in ancestry composition were observed between control and patients, even with respect to therapy response groups. The allelic profile KIR2DL2/KIR2DS2/KIR2DS3 was associated with the chronic hepatitis C (p < 0.0001; OR = 3). Furthermore, the patients also showed a higher mean number of activating genes and a lower frequency of the homozygous AA profile, which is likely secondary to the association with non-AA and/or activating genes. In addition, the KIR2DS5 allele was associated with SVR (p = 0.0261; OR = 0.184).The ancestry analysis of samples ruled out any effects of population substructuring and did not evidence interethnic differences in therapy response, as suggested in previous studies.

A shield against a monster: Hepatitis C in hemodialysis patients

Hepatitis C virus (HCV) infection is highly prevalent among patients on hemodialysis (HD). The prevalence of HCV infection in HD patients varies markedly from country to country. Some factors are especially related to these high prevalence rates, such as blood transfusions and length of dialysis time. Nosocomial routes of transmission including the use of contaminated equipment and patient-to-patient exposure is considered more important. Several prophylactic measures have been suggested to avoid infection by HCV in the HD environment.

Prevalence, genotypes and risk factors associated with hepatitis C virus infection in hemodialysis patients in Campo Grande, MS, Brazil

A survey was conducted among the hemodialysis units of the city of Campo Grande, located in the state of Mato Grosso do Sul in the Mid-west region of Brazil, with the aim of investigating the prevalence, risk factors, and genotypes of hepatitis C virus (HCV) infection. A total of 163 patients were interviewed in five dialysis units. Serum samples were screened for anti-HCV. Positive samples were tested for HCV RNA and genotyped. The prevalence of anti-HCV was 11% (95% CI: 6.8-17.1). A history of transfusion with blood that was not screened for anti-HCV and length of time on hemodialysis were associated with HCV infection. HCV RNA was detected in 12 samples: ten were of genotype 1, subtypes 1a (75%) and 1b (8.3%), and two were of genotype 3, subtype 3a (16.7%).