Decline of hepatitis C infection in hemodialysis patients in Central Brazil: a ten years of surveillance

Global epidemiology of hepatitis C virus in dialysis patients: A systematic review and meta-analysis

Dialysis is a replacement therapy for patients with End-Stage Renal Disease (ESRD). Patients on dialysis are at high risk of acquiring hepatitis C virus (HCV), which has become a leading cause of morbidity and mortality in this population. There is a wide range of prevalence of HCV in dialysis populations around the world. It is still unknown how prevalent HCV infection is among worldwide dialysis patients (including those undergoing hemodialysis and peritoneal dialysis). A review was conducted to estimate the global epidemiology of hepatitis C in dialysis patients. We searched PubMed, Excerpta Medica Database (Embase), Global Index Medicus and Web of Science until October 2022. A manual search of references from relevant articles was also conducted. Heterogeneity was evaluated by the χ2 test on Cochrane's Q statistic, and the sources of heterogeneity were investigated using subgroup analysis. In order to assess publication bias, funnel plots and Egger tests were conducted, and pooled HCV prevalence estimates were generated using a DerSimonian and Laird meta-analysis model. The study is registered with PROSPERO under CRD42022237789. We included 634 papers involving 392160 participants. The overall HCV case fatality rate was 38.7% (95% CI = 28.9-49). The global prevalence of HCV infection in dialysis population group were 24.3% [95% CI = 22.6-25.9]. As indicated by UNSD region, country, dialysis type, and HCV diagnostic targeted; Eastern Europe had the highest prevalence of 48.6% [95% CI = 35.2-62], Indonesia had 63.6% [95% CI = 42.9-82], hemodialysis patients had 25.5% [95% CI = 23.8-27.3], and anti-HCV were detected in 24.5% [95% CI = 22.8-26.2]. Dialysis patients, particularly those on hemodialysis, have a high prevalence and case fatality rate of HCV infection. Hemodialysis units need to implement strict infection control measures.

Persistently high hepatitis C rates in haemodialysis patients in Brazil [a systematic review and meta-analysis]

We conducted a systematic review and meta-analysis of studies assessing HCV infection rates in haemodialysis patients in Brazil (Prospero CRD #42021275068). We included studies on patients under haemodialysis, comprising both convenience samples and exhaustive information from selected services. Patients underwent HCV serological testing with or without confirmation by HCV RNA PCR. Exclusion criteria were the following: absence of primary empirical information and studies without information on their respective settings, study year, accurate infection rates, or full specification of diagnostic tests. Studies with samples ≤ 30 and serial assessments with repeated information were also excluded. Reference databases included PubMed, LILACS, Scopus, and Web of Science for the period 1989–2019. A systematic review was carried out, followed by two independent meta-analyses: (i) studies with data on HCV prevalence and (ii) studies with a confirmatory PCR (i.e., active infection), respectively. A comprehensive set of different methods and procedures were used: forest plots and respective statistics, polynomial regression, meta-regression, subgroup influence, quality assessment, and trim-and-fill analysis. 29 studies and 11,290 individuals were assessed. The average time patients were in haemodialysis varied from 23.5 to 56.3 months. Prevalence of HCV infection was highly heterogeneous, with a pronounced decrease from 1992 to 2001, followed by a plateau and a slight decrease in recent years. The summary measure for HCV prevalence was 34% (95% CI 26–43%) for studies implemented before 2001. For studies implemented after 2001, the corresponding summary measure was 11% (95% CI 8–15%). Estimates for prevalence of active HCV infection were also highly heterogeneous. There was a marked decline from 1996 to 2001, followed by a plateau and a slight increase after 2010. The summary measure for active HCV infection was 19% (95% CI 15–25%) in studies carried out before 2001. For studies implemented after 2001, the corresponding summary measure was 9% (95% CI 6–13%). Heterogeneity was pervasive, but different analyses helped to identify its underlying sources. Besides the year each study was conducted, the findings differed markedly between geographic regions and were heavily influenced by the size of the studies and publication biases. Our systematic review and meta-analysis documented a substantial decline in HCV prevalence among Brazilian haemodialysis patients from 1992 to 2015. CKD should be targeted with specific interventions to prevent HCV infection, and if prevention fails, prompt diagnosis and treatment. Although the goal of HCV elimination by 2030 in Brazil remains elusive, it is necessary to adopt measures to achieve micro-elimination and to launch initiatives towards targeted interventions to curb the spread of HCV in people with CKD, among other high-risk groups. This is of particular concern in the context of a protracted COVID-19 pandemic and a major economic and political crisis.

Viral hepatitis in patients on hemodialysis

Hepatitis B and hepatitis C (HCV) prevalence are higher in people on hemodialysis (HD) than the general population. Through implementation of prevention interventions including vaccines, serologic screening, and post-exposure management, transmissions linked to HD have decreased dramatically. In this manuscript, we review epidemiology of viral hepatitis, summarize current screening and vaccine recommendations, and appraise the available data about efforts to decrease incidence within HD facilities, including isolation of people with viral hepatitis within HD units. Also included is a discussion of the highly effective all-oral HCV treatment options and treatment for HCV in people awaiting kidney transplant.

Decline in hepatitis B and C prevalence among hemodialysis patients in Tocantins, Northern Brazil

Infection control measures have been responsible for a decline in the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections in hemodialysis patients. In Brazil, these measures have been in place since 1996. The aim of this study was to evaluate the current HBV and HCV epidemiology among hemodialysis patients in the State of Tocantins comparing them with those found 14 years ago. There was a significant decline in hepatitis B surface antigen (HBsAg) and anti-HCV prevalence from 4% and 13% in 2001 to 0.8% and 2.8% in 2014-2015, respectively (p < 0.05). Variables related to hemodialysis environment such as working shift and length of time on hemodialysis treatment were no longer associated to HCV and HBV exposure in 2014-2015. A high prevalence of self-reported hepatitis B vaccination was observed in both periods, but only 30% of the individuals showed serological profile of effective previous immunization, suggesting a low compliance with surveillance of hepatitis B immunization in hemodialysis centers. The significant decline in viral hepatitis B and C prevalence in hemodialysis patients in Tocantins underscores the importance of infection control measures, but the low frequency of protective serological profile after immunization against hepatitis B points to the need for greater vigilance of the patients’ vaccination.

[Hepatitis C incidence in hemodialysis patients in Brazil from 2000 to 2003]

The study aimed to estimate the incidence of HCV seroconversion in hemodialysis patients in the Brazilian Unified National Health System (SUS). This was a prospective, non-concurrent study using patients' data identified by deterministic and probabilistic record linkage in the SUS information system. The study included 47,079 patients started on hemodialysis between January 1, 2000, and December 31, 2003, followed until seroconversion or conclusion of the study in 2004. Three percent of hemodialysis patients HCV-seroconverted (1.7 per 100 patient-years). Increased risk of HCV seroconversion was associated with age, glomerulonephritis, geographic region, HIV-positivity, and dialysis service. The observed HCV seroconversion rate was similar to that in developed countries, highlighting evidence of transmission among hemodialysis patients.

Hepatitis C virus in patients on regular hemodialysis in Beni-Suef Governorate, Egypt

BACKGROUND

The prevalence of HCV infection among hemodialysis patients (HD) varies from country to country and from one center to another. Despite the existence of guidelines for a comprehensive infection control program, Egypt is one of the countries with high HCV prevalence. In Egypt, the prevalence of HCV in haemadalysis patients (2015) was 50.7%.

OBJECTIVES

(1) To detect the prevalence of hepatitis C virus (HCV) infection and HCV seroconversion among all hemodialysis patients in Beni-Suef governorate, and (2) To detect factors associated with HCV seroconversion.

MATERIALS AND METHODS

Multicenter retrospective medical records review design was conducted in 13 hemodialysis units in Beni-Suef governorate during May - June 2015; all ESRD (End stage renal disease) patients undergoing hemodialysis were included in the sample. A predesigned questionnaire was used.

RESULTS

The prevalence of the HCV at begin of dialysis was 60.9% and the rate of HCV seroconversion was 9.7%. Univariate analysis confirmed that history of blood transfusion, the non-adherence to infection control guidelines, lack of isolation strategies and history of Shistosomiasis were significant risk factors for seroconversion. Meanwhile multivariate logistic regression analysis confirmed that history of blood transfusion, and history of shistosomiasis were significantly associated with HCV seroconversion.

CONCLUSION

HCV infection still remains a predominant problem among patients on maintenance HD in Beni- Suef governorate History of blood transfusion and history of shistosomiasis were significant risk factors for acquiring HCV infection in these patients.

Hepatitis C Genotype Prevalence in Monastir Region, Tunisia: Correlation between 5' Untranslated Region (5'UTR), Non-structural 5B (NS5B), and Core Sequences in HCV Subtyping

Hepatitis C virus (HCV) is a causative agent of chronic liver disease, cirrhosis, and hepatocellular carcinoma. It constitutes a major public health around the world. There is no vaccine available against HCV, and current therapies are effective in only small percentage of patients. HCV has wide population-specific genotype variability. Genotype knowledge and viral load assessment are equally important for designing therapeutic strategies. Taking into account that the molecular epidemiology of HCV variants circulating in Tunisia is not yet well elucidated, and that, at present, little is known about the distribution pattern of HCV in Monastir region (Tunisia), we aimed, herein, to evaluate the prevalence of HCV genotypes in Monastir and to identify risk-related factors. For this purpose, 50 anti-HCV antibody-positive cases were diagnosed and subjected to viral RNA extraction, amplification, genotyping, and viral load quantification. Molecular epidemiology was studied by 5' untranslated region (5' UTR) sequencing as compared with the non-structural 5B (NS5B) and core region sequences. Overall concordance between 5' UTR, core, and NS5B sequencing was 100 %. The highest prevalent genotype was 1b (50 %) followed by genotypes 1a (16 %), 4a (12 %), 2a (10 %), 2c (8 %), and 3a (4 %). Interestingly, the subtype 1b had a statistically significant higher viral load than the other genotypes followed by subtype 1a. Based on these data, this study revealed a high prevalence of HCV genotype 1 (subtypes 1b and 1a) compared to other genotypes. A continued monitoring of HCV and knowledge of circulating genotypes could impact on future vaccine formulations.

Hepatitis B and C virus infections among patients with end stage renal disease in a low-resourced hemodialysis center in Vietnam: a cross-sectional study

BACKGROUND

Hemodialysis services in Vietnam are being decentralised outside of tertiary hospitals. To identify the challenges to infection control standards for the prevention of bloodborne infections including hepatitis B virus (HBV) and hepatitis C virus (HCV) we tested the magnitude of HBV and HCV infections in the largest unit in Ho Chi Minh City servicing patients with end stage renal disease.

METHODS

All 113 patients provided consent HBV surface antigen (HBsAg) and HCV core antigen (HCV-coreAg) testing. Positive patients were tested for viral genotypes. All participants completed a questionnaire on demographic characteristics, risk factors and previous attendance to other hemodialysis units.

RESULTS

Seroprevalence of 113 patients enrolled was 7% (8/113, 95% CI 2.3%-11.8%) HBsAg, 6% (7/113, 95% CI 1.7%-10.6%) HCV-coreAg and 1% (1/113, 95% CI 0.8%-2.6%) co-infection. Having a HBV positive sexual partner significantly increased the risk of acquiring HBV (P = 0.016, Odds Ratio (OR) =29, 95% CI 2-365). Risk factors for HCV included blood transfusion (P = 0.049), multiple visits to different hemodialysis units (P = 0.048, OR = 5.7, 95% CI 1.2-27.5), frequency of hemodialysis (P = 0.029) and AST plasma levels >40 IU/L (P = 0.020, OR = 19.8, 95% CI 2.3-171). On multivariate analysis only blood transfusion remained significant risk factor for HCV (P = 0.027, adjusted OR = 1.2).

CONCLUSIONS

HCV screening for HCV of blood products must improve to meet the infection prevention challenges of decentralizing hemodialysis services. The level of HCV and HBV in our hemodialysis unit is a warning that universal precautions will be the next challenge for decentralised hemodialysis services in Vietnam.

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.

Genetic diversity of hepatitis C virus quasispecies in chronic renal failure patients in Midwest Brazil

Hepatitis C virus (HCV) quasispecies constitute a dynamic population in a continuous process of variation and selection. To investigate effect of the immune system on the genetic variability of HCV, we compared the hypervariable region 1 (HVR1) of immunosuppressed patients with chronic renal failure (CRF group) to immunocompetent patients with HCV chronic infection (control group). The HVR1 from ten samples of each group was amplified, cloned and sequenced. The HCV quasispecies from the control group had a higher frequency of variable sites in HVR1 (83.9 % vs 59.3 %, p < 0.05), as well as a greater diversity within (intra-patient) and between samples, compared to the CRF group. The clustering of the majority of the quasispecies of the CRF group in the phylogenetic tree also showed the limited diversity of the quasispecies in immunosuppressed patients. Moreover, a higher variability of amino acids at positions 384, 386, 391, 394, 397, 398, 400, 405 and 410 was observed in the control group than in the CRF group, which showed a greater variability only at position 388 (p < 0.05). These data corroborates the hypothesis that the major selective pressure factor is the immune system, which promotes a high degree of diversity in the viral progeny and contributes to a constant evolution of HCV.

Prevalence and risk factors of hepatitis C and B virus infections in hemodialysis patients and their spouses: a multicenter study in Beijing, China

Hemodialysis patients are at risk for hepatitis C and B virus infections. This study investigated the prevalences and risk factors of HCV and HBV infection and the distribution of HCV genotypes among hemodialysis patients and their spouses. From August to November 2011, a cross-sectional study was conducted on 20 hemodialysis units in Beijing to investigate prevalences and risk factors for markers of HCV and HBV among 2,120 patients and 409 spouses. In hemodialysis patients, prevalences of anti-HCV, HCV RNA, and hepatitis B surface antigen (HBsAg) were 6.1%, 4.6%, and 7.0%, respectively. The prevalence of HCV antibodies among spouses was 0.5%, of HCV RNA was 0.2%, and of HBsAg was 4.2%. Risk factors for HCV infection were dialysis duration, blood transfusion, and attending more than one dialysis unit. HBV infection was independently associated with age, family member with hepatitis infection, gender, and surgery. The predominant HCV genotypes were 1b (89.0%) and 2a (7.7%), and genotypes 3a, 3b, and 6a were each 1.1%. A significant decrease in HCV and HBV prevalences in Chinese dialysis units showed that infection control measures were effective. However, because nosocomial transmissions persist, strict adherence to infection control measures should be emphasized to reduce the risk of transmission.

Evidence of association between hepatitis C virus genotype 2b and nosocomial transmissions in hemodialysis centers from southern Brazil

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.

Hepatitis viruses in heamodialysis patients: an added insult to injury?

Hepatitis B (HBV) and hepatitis C (HCV) viruses are the most important causes of chronic liver disease in patients with end stage renal disease on hemodialysis. The prevalence of hepatitis infection among hemodialysis patients is high and varies between countries and between dialysis units within a single country. This case-control study was undertaken to estimate the occurrence of HBV and HCV infections in patients undergoing hemodialysis in our tertiary care center. All patients receving hemodialysis at our centre with HCV or HBV infection were included in the study. The total number of patients admitted for hemodialysis during the study period was 1710. Among these, 26 patients were positive for HBV, 19 were positive for HCV, and 2 were positive for both HCV and HBV. Mean age of the infected cases in our study was 48.63 years. Mean duration of dialysis for infected cases was 4.8 years while that of the noninfected controls was 3.18 years. The mean dialysis interval was twice a week. Interventions to reduce the occurrence of these infections are of utmost need to reduce the risk of long-term complications among hemodialysis patients.

Evaluation of an isolation program of hepatitis C virus infected hemodialysis patients in some hemodialysis centers in egypt

Introduction. Hepatitis C virus (HCV) infection is a significant cause of morbidity and mortality in hemodialysis (HD) patients. Several studies demonstrated nosocomial transmission of HCV among HD patients. Aim. We aimed to evaluate the isolation program of HCV seropositive patients among a group of Egyptian haemodialysis patients to decrease the incidence of HCV seroconversion. Methods. One hundred and fourteen HCV seronegative patients who were receiving regular haemodialysis in different four haemodialysis units in Egypt. The first group included forty six patients on regular hemodialysis in two centers following strict isolation of the HCV seropositive patients, and the second group included sixty eight patients on regular hemodialysis in the other two centers not following this strict isolation. All these patients were followed up over a period of 36 months. Results. There was a significantly higher incidence of HCV seroconversion of patients on hemodialysis in units not following strict isolation of HCV seropositive patients (42.9%) than those on regular hemodialysis in units following strict isolation (14.8%). Conclusions. In HD units with a high prevalence of HCV+ patients, strict isolation of HCV+ patients in combination with implementation of universal prevention measures can limit the spread of HCV infection in HD patients.

Incidence of hepatitis C virus infection in patients on hemodialysis: a systematic review and meta-analysis

Hepatitis C virus infection is a perennial concern for hemodialysis units because the prevalence of hepatitis C is significantly higher there than in the general population. Through a systematic review and meta-analysis, we aim to assess the incidence rate of hepatitis C virus infection in hemodialysis units and explore its potential risk factors. Five electronic databases were used to search articles from 1990 to 2012, including PubMed, Embase, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, and Wanfang. A random-effects analysis was used to estimate the overall incidence rate of hepatitis C virus infection. A subgroup analysis and meta-regression analysis were conducted to explore factors associated with heterogeneity between studies. Twenty-two eligible articles were found, including 23 incidence rate estimates. The overall incidence rate of hepatitis C virus infection was 1.47 per 100 patient-years (95% confidence interval [CI] 1.14 to 1.80). In the subgroup analysis, the pooled incidence rate was 4.44 (CI 2.65, 6.23) per 100 patient-years in the developing world and 0.99 (CI 0.66, 1.29) per 100 patient-years in the developed world. [Correction added on 2 November 2012, after first online publication: Pooled incidence rate in the developed world has been changed.] In addition, in hemodialysis units with higher prevalence, the incidence rate of hepatitis C virus infection also tended to be higher. Meta-regression analysis showed that the country's development level and initial HCV prevalence combined could explain 67.91% of the observed heterogeneity. The incidence rate of hepatitis C virus infection among patients on hemodialysis was significantly high. Efforts should be taken to control hepatitis C virus infection in hemodialysis units, especially in developing countries.

Kinetics of hepatitis C virus load and hemodialysis: is there any influence of the reuse of dialysis membrane on HCV viremia?

BACKGROUND

Patients with chronic kidney disease (CKD) on regular hemodialysis are at increased risk of acquiring hepatitis C virus (HCV). Although controversial, a distinct dynamic of the HCV load has been reported in this group - a lower HCV viremia compared to non-uremic patients. The reasons for this remain unclear, but the host immune response related to the hemodialysis procedure and the reuse of dialysis membranes are the most investigated factors.

METHODS

We analyzed the kinetics of HCV RNA viremia in 21 hemodialysis patients infected with genotype 1, through a highly sensitive quantitative method (real-time polymerase chain reaction), immediately before and at the end of the first use and the last reuse of the cellulose diacetate dialysis membrane.

RESULTS

Initial HCV load did not correlate with demographic or biochemical parameters, but higher HCV viremia was associated with a longer time on hemodialysis (r = 0.44, p = 0.04). Although not significant, HCV RNA decreased in 11/21 (52.3%) patients after the first dialysis session (median 279,000 vs 176,000 IU/ml, p = 0.91). However, a significant increase in HCV RNA viremia was observed in 17/21 (80.9%) patients after the tenth session (median 187,000 vs 342,000 IU/ml, p = 0.009).

CONCLUSIONS

Except for the first session of hemodialysis, we did not confirm a decrease in HCV viremia related to the time on hemodialysis or with the reuse of the dialysis membrane. Factors other than the reuse of the dialysis membrane might be involved in the multifaceted kinetics of HCV RNA in CKD patients on hemodialysis.

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.

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.

Co-infecção por HIV/HCV em hospital universitário de Recife, Brasil

OBJETIVO: Estimar a prevalência do vírus da hepatite C (HCV) e fatores de risco associados com a co-infecção em pessoas soropositivas para HIV. MÉTODOS: Estudo do tipo transversal, descritivo e analítico, com 343 portadores do HIV atendidos em um hospital universitário de Recife (PE), no período de março a dezembro de 2003. Os pacientes foram submetidos a um questionário padronizado sobre os fatores de risco. Nas amostras de soro foram pesquisados o anti-HCV pelo ELISA, o HCV-RNA por meio da RT-PCR e a identificação dos genótipos foi realizada no equipamento ABI377 (PE Biosystems®). As análises estatísticas utilizadas foram a univariada, a multivariada e a regressão logística múltipla. RESULTADOS: A prevalência encontrada para o HCV foi de 4,1% (14/343) pelo ELISA e de 3,2 % (11/343) quando utilizada a RT-PCR. Os genótipos mais freqüentes foram 1b (45%), 3 (33%) e 1a (22%). A faixa etária com maior proporção de co-infectados foi a de 30 a 39 anos, com predomínio do sexo masculino (64,3%). Após regressão logística múltipla, apenas a variável transfusão sangüínea permaneceu como fator de risco para o HCV (OR=4,28; IC 95%: 1,44;12,73). CONCLUSÕES: A prevalência da co-infecção HIV/HCV foi baixa, a transfusão sangüínea foi um fator de risco e o genótipo 1b do HCV foi o mais freqüente.

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%).

Molecular analysis and patterns of ALT and hepatitis C virus seroconversion in haemodialysis patients with acute hepatitis

BACKGROUND

Haemodialysis (HD) continues to carry the risk of hepatitis C virus (HCV) transmission, with delayed seroconversion and often normal alanine aminotransferase (ALT) values increasing the likelihood of undetected infection and thus uninterrupted spread of HCV. The aim of this study was to identify the characteristic patterns of ALT changes and seroconversion during an outbreak of HCV in a HD unit. We also wanted to establish the relationship between infecting viruses using molecular analysis.

METHODS

All patients (n = 72) and staff (n = 23) of the HD unit were prospectively followed for 14 months. Serial measurements for ALT, HCV antibody and HCV-RNA were performed besides HCV sequence analysis.

RESULTS

The initial screening for anti-HCV and HCV-RNA confirmed chronic infection in 16/72 (22%) subjects and identified three subjects with recent seroconversion. In addition, five cases were reverse transcription-polymerase chain reaction positive alone for a total of eight recent cases. The interval between the initial observation of ALT changes and seroconversion varied from 1 to 8 months, and in several individuals ALT fluctuations only below the upper limit of normal were detected. However, relating each subject's ALT values to ALT at baseline, ALT levels increased between 1.6- and 4.7-fold. Molecular analysis provided evidence for transmission from two chronically infected source patients, probably because of inappropriate infection control measures.

CONCLUSION

Our data highlight the importance of well-implemented safety precautions and regular HCV-RNA testing to prevent the further spread of HCV in this population, and suggest the use of ALT baseline values to identify infections that may remain unnoticed otherwise.

Hepatitis C in hemodialysis patients: current global magnitude, natural history, diagnostic difficulties, and preventive measures

Hepatitis C virus (HCV) infection is a significant cause of morbidity and mortality in hemodialysis (HD) patients. The reported prevalence of HCV among the HD population has varied greatly from 1.9 to 84.6% in different countries in recent years. The length of time on HD is generally believed to be associated with HCV acquisition in HD subjects. Nevertheless, several recent reports failed to recognize any significant role of blood transfusion. Although there are some considerations about the accuracy of serologic testing in detecting HCV in HD patients, the accumulated data in this review suggest the false-negativity rate to be not more than 1.66% (153/9,220). Therefore, substituting virologic for serologic testing in the routine diagnosis of HCV infection in HD patients seems unreasonable. Several phylogenetic analyzes of viral isolates suggested nosocomial patient-to-patient transmission of HCV among HD patients for which the main potential source is believed to be contaminated hands and articles. However, isolation of HCV-infected HD patients and use of dedicated machines are currently unjustified while strict adherence to universal precautions seems to be enough to control disease spread in HD units. The present article is an update on epidemiological and clinical features of HCV in HD population.

Infection by the hepatitis C virus in chronic renal failure patients undergoing hemodialysis in Mato Grosso state, central Brazil: a cohort study

BACKGROUND

Hepatitis C virus (HCV) is a significant problem for patients undergoing hemodialysis therapy. This situation has never been studied in Mato Grosso state, central Brazil. This study was conducted aiming to estimate the prevalence of the anti-HCV and the incidence of seroconversion in the main metropolitan region of the state.

METHODS

433 patients from the six hemodialysis units were interviewed and anti-HCV was tested by a third-generation enzyme immunoassay. An open cohort of patients who tested negative for anti-HCV at the entry of the study was created and seroconversions was assessed monthly. The staff responsible for the units were interviewed to assess whether the infection control measures were being followed. Logistic and Cox regression analysis were performed in order to assess risk factor to HCV.

RESULTS

The entry on the study took place between January 2002 and June 2005. 73 out of 433 (16.9%, CI 95%: 13.3-20.8) was found to be anti-HCV reactive. The multivariate analysis indicated as risk factors associated to anti-HCV the duration of the hemodialysis treatment, the number of transfusions received, and the unit of treatment. An open cohort of 360 patients who tested negative for anti-HCV was created, with a following average of 24 (+/- 15) months. Forty seroconversions were recorded corresponding to an incidence density of 4.6/1000 patient-months, ranges 0 to 30 among the units. Cox regression indicated the time of hemodialysis (RR = 2.2; CI 95%: 1.1-4.6; p < 0.05) and the unit where treatment was performed (RR = 42.4; CI 95%: 9.9-180.5; p < 0.05) as risk factors for seroconversion. The three units with highest anti-HCV prevalence and incidence were identified as those that more frequently failed to apply control measures.

CONCLUSION

The study demonstrated high prevalence and incidence of anti-HCV in some of the hemodialysis units. Time on hemodialysis therapy was an independent factor associated to HCV. Blood transfusion was associated with anti-HCV in initial survey but was not important in incident cases. Failure of applying control measures was more evident in units with the highest HCV prevalence and incidence. The results suggest that nosocomial transmission was the main spread factor of HCV in the studied population.

Low prevalence of hepatitis C virus infection in Amerindians from Western Venezuela

Previous studies have not found hepatitis C virus (HCV) infection in Amerindians from Western Venezuela. A survey of 254 Bari and Yukpa natives aged 10-60 years (mean +/- SD age = 35 +/- 5.4 years) from four communities, two Bari and two Yukpa, in this area were studied to assess the prevalence of antibodies to HCV (anti-HCV) and HCV RNA among these indigenous populations. Serum samples were examined initially for anti-HCV by a four generation enzyme-linked immunosorbent assay (ELISA). Reactive samples were then tested using a third generation recombinant immunoblot assay (RIBA-3). Viral RNA was investigated in all immunoblot-reactive samples by a nested polymerase chain reaction (PCR) method. Six (2.3%) of 254 natives were positive by ELISA, one (2.2%) of these reactive samples were positive by RIBA, and four (1.5%) were indeterminate. Only two (0.8%) were positive by PCR, corresponding to 1 (2.1%) of 47 inhabitants of a Yukpa community and to 1 (2.2%) of 45 subjects of a Bari community. Iatrogenic is thought to play a role in acquisition of the infection. The findings indicate a HCV focus of low endemicity and are compatible with a low degree of exposures of the natives to the virus. Studies are necessary to assess the risk factors for infection in these Amerindians.

Molecular and epidemiological study on nosocomial transmission of HCV in hemodialysis patients in Brazil

An epidemiological and molecular study of hepatitis C virus (HCV) infection was carried out in Brazilian hemodialysis centers. A total of 1,095 patients in all 15 hemodialysis centers in the State of Goiás, Brazil, were studied. All patients were interviewed for possible risk factors to HCV infection and serum samples tested for anti-HCV by ELISA and for HCV RNA by nested RT-PCR of the 5' NC region. For sequence analysis, HCV RNA amplification for the NS5B region (nt 8,279-8,619) was performed. The phylogenetic tree was generated with MrBayes, and clusters with support values above 0.85 were considered epidemiologically related. Of the 1,095 patients, 180 were anti-HCV and/or HCV RNA positive, resulting in an overall prevalence of 16.4% (95% CI: 14.3-18.7). The prevalence of HCV infection in the dialysis centers ranged from 0% to 47.7%. Multivariate analysis of risk factors revealed that history of blood transfusion not screened for anti-HCV and length of time on hemodialysis were independently associated with HCV infection in this population. One hundred six samples could be amplified and sequenced in the NS5B region. Among them, plylogenetic tree analysis revealed that 69 sequences form 13 separated clusters, which were supported by credibility intervals ranging from 85% to 100%, indicating a very close relationship among the HCV isolates and therefore a likely transmission of the virus between patients. By combining phylogenetic analysis with epidemiological data, routes of transmission between the clustered-related-patients could be suggested. These findings provide evidence for nosocomial transmission of HCV in Brazilian hemodialysis centers.