Prevalence of occult hepatitis C infection in chronic hemodialysis and kidney transplant patients

Silent Threat: Fatal Consequences of Occult Hepatitis C Viral Infection in a Kidney Transplant Recipient: A Case Report and Literature Review

We present the case of a 54-year-old female patient with a history of treated hepatitis B who underwent living-related kidney transplantation from her son. The timing of the transplantation and immediate postoperative period was uneventful, with no significant complications. However, within 3 months, she was repeatedly hospitalized because of persistent jaundice, abdominal pain, and diarrhea, and liver function tests indicated considerable liver injury. Extensive investigations have revealed an occult hepatitis C virus infection that occurred before transplantation. The patient subsequently developed acute fulminant liver failure accompanied by severe gastrointestinal bleeding. Despite aggressive medical management, her condition deteriorated rapidly, leading to death. This case underscores the importance of comprehensive viral screening in transplant recipients, particularly those with risk factors or symptoms of hepatitis C virus infection, to prevent potentially life-threatening complications following transplantation.

Prevalence of occult hepatitis C virus infection (OCI) among hemodialysis patients; a cross-sectional study from Lorestan Province, Western Iran

Patients with chronic kidney disorders, such as hemodialysis, are at a higher risk of infection with hepatitis viruses than the other population due to high nosocomial transmission by the dialysis units. The incidence of occult HCV infection (OCI) among chronic hemodialysis (CHD) remains controversial and the real burden of HCV in this population may be affected by the rate of OCI. This study aimed to evaluate the prevalence of OCI among patients with CHD from Lorestan province, Western Iran. In this cross-sectional study, whole blood samples were collected from 122 patients with CHD. Subsequently, anti-HCV antibody and HCV-RNA were assessed in serum/peripheral blood mononuclear cells (PBMCs) using Enzyme-Linked Immunosorbent Assay and Real-Time PCR technique, respectively. Out of the 122 patients, 61.15% were male and 38.8% were female. Regarding HCV results, out of the 122 studied patients, 4 cases (3.3%) were positive for anti-HCV IgM Ab and 3 patients (2.47%) for anti-HCV IgG Ab in their serum. Moreover, none of the 122 patients were positive for HCV-RNA in serum samples, while in PBMC samples, two patients (1.6%) tested positive for HCV-RNA, of which one patient was anti-HCV IgG Ab positive. Furthermore, the prevalence of OCI was correlated with the history of blood transfusion and serum level of transaminases (P = 0.012). The results of the current study suggest that there is a potential risk of occult HCV infection among patients undergoing hemodialysis. Therefore, it is necessary to use appropriate molecular techniques for early diagnosis and treatment of these patients.

Newly diagnosed hepatitis C infection after pancreas transplantation with multiple treatment failures

This case represents the first report of a detected hepatitis C virus (HCV) infection following a pancreas transplantation that failed two different sofosbuvir (SOF)-based treatments. We present the case of a woman in her 30s with a history of kidney transplantation, who developed viremic symptoms 3 months after pancreas transplantation and with two subsequent negative HCV antibody tests. Further work-up revealed a positive HCV RNA test (genotype 1A, treatment naive). Two different direct-acting antiviral agents regimes with SOF failed in our case, and the patient achieved a sustained virological response with a 16-week course of glecaprevir/pibrentasvir.

Laboratory Evaluation of Hepatitis C Virus Infection in Patients Undergoing Hemodialysis from North East India

INTRODUCTION

Subjects undergoing hemodialysis have enhanced vulnerability to hepatitis C virus (HCV) infection due to invasive procedures and poor infection control practices. Early detection and treatment are essential to prevent cross-infection and mortality/morbidity. However, common use anti-HCV antibody tests lack the necessary accuracy, and alternative tests (e.g. core antigen detection kits) which are available need to be examined as a viable alternative.

METHOD

A total of 270 continuous serum samples were collected from patients undergoing dialysis within 15 months of study period. Sequentially, multiple tests were performed - immunochromatography-based rapid test, third-generation ELISA i.e. (anti-HCV antibody detection), fourth-generation ELISA (HCV antigen-antibody combined detection assay), and HCV RNA quantitative real time polymerase chain reaction (qPCR) assay. Diagnostic parameters of serological kits were compared in terms of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and so on. Statistical Package for the Social Sciences was used.

RESULTS

HCV-combined core antigen-antibody assays performed better than other serological assays in reference to the gold standard HCV RNA. This fourth-generation assay yielded a Kappa value of 0.947 compared with the value of 0.747 and 0.619 for anti-HCV ELISA and rapid detection test. Other parameters such as sensitivity, specificity, PPV, NPV, and so on were also better for fourth-generation ELISA compared with third-generation ELISA and other serological assays. HCV RNA was negative in 7.3% of anti-HCV-positive patients and was detected in 11.4% of anti-HCV ELISA-negative patients. In about 1.6% of HCV RNA-positive cases, fourth-generation ELISA was negative and had low HCV viral load (650 IU/ml and below). Fourth generation ELISA detected additional 7.4% HCV positive cases (compared to third generation kits) and upon cost effective analyis, additional cost to be bear for the better detection (by fourth generation kit) was found to be only INR 27 per 1% increased case detection.

CONCLUSION

In resource scant setup, screening and follow-up of patients undergoing hemodialysis can be performed by fourth-generation HCV ELISA (antigen-antibody combined assay) instead of the current practice of anti-HCV antibody ELISA. Better yield in detection rate will compensate for slight addition to costs.

Occult Infection with Hepatitis C Virus: Looking for Clear-Cut Boundaries and Methodological Consensus

The sustained virologic response and elimination of HCV is widely viewed as a true cure of chronic hepatitis C as it associates with amelioration of histological liver damage and improved clinical outcomes. Therefore, the existence and clinical burden of occult HCV infection (OCI) has been a controversial issue for many years. In this review, we summarize recently published data that adds new information on the molecular and clinical background of OCI and its epidemiological significance. We also identify and discuss the most important methodological pitfalls, which can be a source of inconsistency between studies. Data that have accumulated so far, strongly support the existence of extrahepatic HCV replication in individuals negative for serum HCV-RNA by conventional clinical tests. OCI emerges as a condition where the immune system is unable to fully resolve infection but it is continuously stimulated by low levels of HCV antigens, leading to progression of liver pathology and extrahepatic HCV-related complications. Moreover, the development of monitoring strategies or management guidelines for OCI is still hampered by the lack of clear definition and the confusion regarding its clinical significance. Careful study design and the introduction of uniform protocols for the detection of low-level HCV-RNA are crucial for obtaining reliable data on OCI.

Occurrence and clinical characteristics of occult hepatitis C virus infection in hemodialysis units at Ismailia, Egypt

BACKGROUND AND AIMS

Occult hepatitis C infection is defined as the presence of hepatitis C virus RNA in peripheral blood mononuclear cells (PBMC) ± hepatocytes in the absence of HCV-RNA in serum. It has been a lot of debate and controversy in recent years and not discussed well. This issue has not been discussed or investigated in Egypt, especially in patients on hemodialysis in Ismailia. This study is the first one to investigate the prevalence of occult HCV infection in large populations of chronic hemodialysis (CHD) patients in Ismailia, Egypt.

METHODS

Our study is cross-sectional analytic and included 204 CHD patients; who are negative for HCV infection. Sensitive commercial real-time assay was used to detect HCV-RNA in PBMC. In our study, the presence of genomic HCV-RNA in PBMCs of all these patients was detected by real-time PCR. On the other hand, 22 patients on hemodialysis with an established diagnosis of chronic hepatitis C virus infection were included as a control group and examined by real-time PCR was used to evaluate HCV infection.

RESULTS

Occult HCV infection is defined as the presence of HCV-RNA in PBMNCs in patients on chronic hemodialysis, and it was found in 14/204 (7%) of the patients. Patients who were on CHD for a longer time are susceptible to occult HCV infection, and their mean alanine aminotransferase levels are significantly higher during the last 3 months before study entry. In comparison, chronic HCV patients have elevated bilirubin, aspartate transferase and alanine transferase than occult HCV infection.

CONCLUSIONS

The prevalence of occult HCV infection was 7% in our CHD patients. No available data are showing the virulence of this form of virus. However, further studies in other geographic populations with high HCV endemicity are needed to clarify the significance of occult HCV infection in these patient groups, in addition to test for the presence of negative antigenomic strand to confirm or disconfirm the reliability of occult HCV.

Hepatitis C in Chronic Kidney Disease: An Overview of the KDIGO Guideline

Hepatitis C virus (HCV) infection is a global health problem with significant health and economic burden, which can lead to chronic kidney disease (CKD) and affect multiple organ systems. In addition, prevalence of hepatitis C remains higher in patients with CKD, including those on chronic hemodialysis and in individuals with a kidney transplant than in the general population. There has been a dramatic shift in the management of hepatitis C since Kidney Disease: Improving Global Outcome (KDIGO) published its 2008 guideline for the prevention, diagnosis and management of hepatitis C in CKD. As a result, KDIGO published in 2018 an update to this guideline. In this narrative review, we present a synopsis of the guideline, including recommendations for screening and detection of HCV in CKD, treatment of HCV in patients with CKD, treatment of HCV before and after kidney transplantation, prevention of HCV transmission in hemodialysis units, and treatment of kidney disease related to HCV infection. We focus on the clinical aspects of using direct acting antivirals (DAAs) in patients with advanced CKD (G4 and G5), those on dialysis and kidney transplant recipients. We emphasize the importance of carefully managing drug-drug interactions between DAAs and immunosuppressive agents. We discuss timing of HCV treatment before vs. after kidney transplantation. Finally, we highlight areas of uncertainty where further research is needed before any definitive recommendations can be made.

Prevalence of Hepatitis B, C, and D in Germany: Results From a Scoping Review

Background: One of the five strategic directions in the World Health Organization global health sector strategy on viral hepatitis 2016-2021 is to generate strong strategic information for focused action to understand the viral hepatitis epidemic and focus the response. Knowledge of national prevalence is a cornerstone of strategic information. Germany is considered to be a low prevalence country for viral hepatitis B, C, and D, however the prevalence is likely to be higher among at-risk groups. Methods: The aim of this work was to give a detailed overview of the prevalence of viral hepatitis B (HBsAg, anti-HBc), C (anti-HCV, HCV RNA), and D (anti-HDV, HDV RNA) in different population groups in Germany. Therefore, we analyzed the results of a comprehensive literature search on various aspects of the epidemiological situation of hepatitis B, C, and D in Germany. Eligible publications including information on hepatitis B, C, and D prevalence were extracted from the overall spreadsheet table and summarized and analyzed based on virus and different population groups. A quality appraisal was performed using a checklist developed by Hoy et al. to assess risk of bias in prevalence studies. Results: Overall, 51 publications were identified through the literature search. The overall prevalence of HBsAg in the general (and proxy) population ranged from 0.3 to 1.6%. Among at-risk groups, including clinical populations and health care workers, the HBsAg prevalence ranged from 0.2% (among rheumatic patients) to 4.5% among HIV positive patients. The overall prevalence of anti-HCV in the general (and proxy) population ranged from 0.2 to 1.9%. Among at-risk groups, including clinical populations and health care workers, the anti-HCV prevalence ranged from 0.04% (among health care workers) to 68.0% among people who inject drugs. Conclusions: The hepatitis B and C prevalence in the general population in Germany is low. Prevalence is high to very high among at-risk populations, however for some groups evidence was incomplete or missing completely. To reach the elimination goals in Germany and implement a targeted response, more research among at-risk groups is needed.

Prevalence, risk factors and impact of occult HCV infection on liver morbidity among haemodialysis patients: hospital-based cross-sectional study

OBJECTIVES

Haemodialysis (HD) patients are at risk for blood-borne infections as occult HCV infection, which justifies comprehensive studies. We aimed to determine the prevalence and risk factors of occult HCV infection (OCI) among HD patients.

MATERIAL AND METHODS

One hundred eligible HD patients, with no evidence of overt HCV or HBV and HBV vaccinated were recruited, and tested for HCV, HBV markers and HCV RNA. Two HCV-positive patients were excluded and peripheral mononuclear cells of 98 patients were verified for viraemia.

RESULTS

OCI was detected in eight (8.16%); with a median viral load of 7010copies/ml. Their mean age was 30.63 (±18.87 years) compared to others (41.73 ± 15.93) (p = .069). History of surgery, dental procedure, and blood transfusion was comparably high in both groups (p > .05). All OCI patients underwent dialysis twice weekly compared to 48.9% of non-OCI patients (p = .006). OCI patients had a significantly higher mean duration of dialysis (12.63 ± 6.74 years), and a significantly higher frequency (50%) of HCV Ab compared to 6.48 ± 4.76, and 10%, respectively, in non-OCI patients. None of OCI patients was reactive to HBcAb compared to 34 (37.8%) patients without (p = .048). Evidence of liver morbidity was detected in 5 (62.5%) OCI patients compared to 43 (47.7%) of non-OCI patients (p > .05).

CONCLUSION

Among our HD patients, OCI is considered a comorbid finding associated with mild liver morbidity that warrants strict infection control and periodic testing for blood borne infections.

Eliminating Hepatitis C Virus From a Prevalent Kidney Transplant Recipient Population: A Single-Center Study in Belgium in the Direct-Acting Antivirals Era

BACKGROUND

Direct-acting antivirals (DAAs) have revolutionized the treatment of hepatitis C virus (HCV) infection. Although previous studies have reported positive results with DAAs after kidney transplantation (KT), their impact on the prevalence of HCV viremia (HCVv) in prevalent kidney transplant recipients (KTRs) remains ill defined.

METHODS

We retrospectively reviewed the HCV status of all patients followed at Cliniques Universitaires Saint-Luc, Brussels, Belgium, outpatient KT clinic between January 2014 and December 2018. We collected the clinical features of KTRs treated with DAAs during this period and calculated the annual prevalence of HCVv over this period.

RESULTS

Out of 1451 KTRs, 22 (1.52%) had HCVv in 2014 to 2018. From 2014 to 2018, the annual prevalence of HCVv dropped from 1.97% to 0.43%, (P < .001). Fourteen KTRs were treated with DAAs a median of 197 months (range: 5-374) after KT, mostly (79%) in 2017 after reimbursement restrictions of DAAs for KTRs in Belgium were removed. DAA treatment was safe with a sustained virological response rate at 12 weeks after treatment (SVR12) of 93%. Two patients died 14 months (lymphoma, despite SVR12) and 7 months (hepatocarcinoma, no SVR12) after DAAs initiation, respectively. Among HCVv KTRs not treated with DAAs (n = 8), 2 lost their graft, 5 died, and 1 is initiating therapy. The current prevalence of HCVv in the cohort is 0.08%, with a single patient currently on treatment.

CONCLUSION

Treatment with DAAs led to a dramatic decrease of HCVv prevalence in this KTR cohort. DAA use was safe and effective. Elimination of HCV is possible at KT clinics.

The epidemiology of Hepatitis B, C and D in Germany: A scoping review

BACKGROUND

Germany is considered to be a low prevalence country for viral Hepatitis B, C and D (HBV, HCV, HDV). However, the burden of disease can be high among subpopulations. To meet the world Health Organization (WHO) viral hepatitis (VH) elimination goals, a national strategy was developed by the German government in 2016. We performed a scoping review to understand the baseline epidemiological situation in Germany regarding burden of disease, sequelae and care of HBV, HCV and HDV as a reference to monitor the progress of the national VH elimination and to identify further knowledge gaps and research needs.

METHODS

The protocol of the systematic review was prepared following the PRISMA statement guidelines for scoping reviews. Relevant search terms were used to identify eligible studies according to the research questions. We searched six online databases for original work published between January 2005 and March 2017. Based on the identified references, a matrix was developed presenting the eligible literature by targeted population group and outcome category.

RESULTS

104 publications were eligible for extraction covering 299 outcome results. The population groups targeted in the identified studies included the general population and proxy populations, a range of clinical populations, people who inject drugs, men who have sex with men, healthcare workers, people in prisons and different migrant/mobile populations. Other vulnerable populations (e.g. sex workers) were not targeted. Overall, good evidence was found for HBV and HCV prevalence and HBV vaccination coverage in the GP and proxy populations. Evidence for these outcomes was weaker in populations at risk for VH. For HBV and HCV incidence and mortality, we identified large evidence gaps in all population groups. Outcomes on VH sequelae and care were mainly covered by studies in clinical populations of people living with viral hepatitis. For HDV the overall evidence available was scarce.

CONCLUSIONS

We created a comprehensive evidence-based overview on the current epidemiological situation of viral hepatitis in Germany. We identified knowledge gaps for further research and established a baseline for future monitoring of viral hepatitis elimination goals in Germany.

Highly effective treatment response and well tolerability by all oral direct acting antivirals for chronic hepatitis C patients post organ transplantation

BACKGROUND

Immunosuppressant-related acceleration of fibrosis has been documented in chronic hepatitis C (CHC) patients who receive organ transplantation (Tx), and sustained virological response (SVR) rates for these patients by pegylated interferon (IFN)-based therapy are generally poor and associated with unfavorable safety profiles. In addition, IFN treatment varies by patient and poses a high risk of post-renal Tx graft rejection. This study was aimed to investigate the efficacy and safety of all oral direct acting antivirals (DAAs) for CHC patients following organ Tx.

METHODS

A total of 32 organ Tx (liver: 17, kidney: 13, kidney then liver: 1, and heart: 1) patients with CHC on an oral DAA (paritaprevir/ritonavir, ombitasvir, and dasabuvir: 11, daclatasvir and asunaprevir: 4, sofosbuvir-based: 17) were enrolled in the study. DAAs regimen was based by genotype/subtype, patient characteristics, drug interaction profiles, and health insurance coverage.

RESULTS

Mean patient age was 61.4 ± 9.5 years, 50.0% male, and 15.6% with cirrhosis. Fourteen (43.7%) patients experienced unsuccessful IFN treatment. Genotype distribution was as follows: 1a: 6, 1b: 17, 2: 7, 3: 1, and 6: 1. Mean time between Tx and DAAs therapy was 77.3 ± 11.0 months. Baseline HCV RNA before DAAs was 6.20 ± 0.19 log10 IU/mL. After DAAs, the distribution of week 2 HCV RNA was as follows: <15 IU/mL (53.1%), 15 to 50 IU/mL (15.6%), 50 to 100 IU/mL (6.3%), and >100 IU/mL (25.0%), respectively. The rates of undetectable HCV RNA (<15 IU/mL) at week 4 and end-of-treatment were 93.8% and 100%, respectively. Subjective adverse events during therapy were generally mild, with no treatment terminations. After posttreatment follow-up, all 32 patients (100%) achieved SVR12.

CONCLUSION

Highly responsive treatment and favorable tolerability were achieved by all oral DAAs in this difficult-to-treat patient population.

Hepatitis B and C among healthcare workers and patient groups at increased risk of iatrogenic transmission in the European Union/European Economic Area

In the European Union/European Economic Area (EU/EEA) approximately 9 million people are chronically infected with hepatitis B virus (HBV) or hepatitis C virus (HCV), and many are undiagnosed. Targeted active case finding initiatives are needed. Iatrogenic transmission of HBV/HCV is relevant in Europe but people at risk of infection are often overlooked. This study aimed to identify groups at increased risk of HBV/HCV infection due to iatrogenic transmission, including healthcare workers, and to estimate incidence and prevalence. PubMed and Embase were systematically searched in February 2017 using strings combining terms for HBV/HCV, occurrence and population subgroups. All retrieved publications were screened and included articles were quality assessed. A predefined set of variables were extracted, and detailed summary tables were developed per population group of interest, virus and outcome. Thirty-eight articles were included, two reported on HBV, 22 on HCV and 16 on both, contributing 70 estimates of prevalence or incidence among: haemodialysis recipients, diabetes patients, recipients of substances of human origin, recipients of medical/dental procedures and healthcare workers. Estimates varied widely from 0.4% to 11.7% for HBV and from 0.7% to over 90% for HCV with most being higher than in the general population. Despite the limited number of studies retrieved, mostly old and focused on populations with multiple risk factors, our findings highlight the importance of considering population groups at higher risk for HBV/HCV iatrogenic transmission as target groups for active case finding in the EU/EEA. Test offers should be guided by individual risk assessment alongside local epidemiological data and local context.

Frequency of Hepatotropic Viruses Leading To Deranged Liver Function Tests in Renal Transplant Recipients

OBJECTIVES

The preferred modality for renal replacement therapy is renal transplantation. Marked improvements in early graft survival and long-term graft function have made renal transplantation a more cost-effective alternative to dialysis. The presence of liver disease in the posttransplant period adversely affects graft function and survival. Determining the cause of deranged liver function tests can be helpful in treating the underlying cause, leading to improved graft survival and overall quality of life in patients after renal transplant. Here, we determined the frequency of hepatotropic viral infections leading to deranged liver function tests in renal transplant recipients.

MATERIALS AND METHODS

Our study included 132 patients with deranged liver function tests who had undergone renal transplant within the past 6 months. Reactivity and nonreactivity of hepatotropic viruses leading to deranged liver function tests were recorded.

RESULTS

Average age of patients was 37.17 ± 8.75 years. There were 84 male (63.64%) and 48 female (36.36%) patients. Rates of hepatitis C virus antibodies and hepatitis B surface antigen were 62.88% (83/132) and 37.12% (49/132), respectively, whereas no patients had hepatitis E virus immunoglobulin M antibodies or hepatitis A virus immunoglobulin M antibodies.

CONCLUSIONS

Among the hepatotropic viral infections leading to deranged liver function tests in renal transplant recipients, hepatitis B virus accounted for a small fraction. In contrast, hepatitis C virus was highly prevalent in transplant recipients who developed deranged liver function tests. Renal transplant recipients with hepatic viral infections have worse patient and allograft survival after transplant compared with noninfected renal transplant recipients. We recommend that transplant candidates be screened for hepatitis B and C virus infection, thus allowing increased graft survival and improved quality of life in renal transplant recipients.

Living kidney donation in individuals with hepatitis C and HIV infection: rationale and emerging evidence

PURPOSE OF REVIEW

HIV-infected (HIV+) and hepatitis C virus-infected (HCV+) individuals with end-stage renal disease (ESRD) have decreased access to kidney transplantation. With new opportunities provided by the HIV Organ Policy Equity (HOPE) Act and direct-acting antivirals (DAAs) for HCV, we explore the potential risks and benefits of living donor kidney transplantation from HIV+ or HCV+ donors, from the perspective of both donor health and recipient outcomes.

RECENT FINDINGS

The HOPE Act permits organ donation from both deceased and living HIV+ persons to HIV+ recipients; however, there is only clinical experience with HIV+ deceased donors to date. Empirical evidence demonstrates a low but acceptable risk of ESRD in potential HIV+ living donors without comorbidities who have well-controlled infection in the absence of donation. With the availability of potent DAAs for eradication of HCV infection, growing evidence shows good outcomes with HCV seropositive and/or viremic deceased kidney donors, providing rationale to consider HCV+ living donors.

SUMMARY

HIV+ and HCV+ living donor kidney transplantation may improve access to transplant for vulnerable ESRD populations. Careful evaluation and monitoring are warranted to mitigate potential risks to donors and recipients.

Balancing the risk and rewards of utilizing organs from hepatitis C viremic donors

PURPOSE OF REVIEW

Owing to long waitlist times and high waitlist morbidity and mortality, strategies to increase utilization of hepatitis C viremic-deceased donor organs are under investigation in kidney, liver, heart, and lung transplantation.

RECENT FINDINGS

Direct-acting antiviral medications for hepatitis C virus infection have high cure rates and are well tolerated. Small, single-center trials in kidney and heart transplant recipients have demonstrated that with early posttransplant direct-acting antiviral therapy, 100% of uninfected recipients of hepatitis C viremic organs have been cured of infection after transplantation.

SUMMARY

In this manuscript, we review the risks and rewards of utilizing hepatitis C viremic organs for transplantation.

Hepatitis C virus infection in kidney transplantation-changing paradigms with novel agents

Hepatitis C virus (HCV) is a common cause of increased morbidity and mortality in kidney transplant patients. It is associated with posttransplant glomerulonephritis, chronic allograft nephropathy, and New Onset Diabetes after Transplant (NODAT). In the past, HCV was difficult to treat due to the presence of interferon alpha-based therapies that were difficult to tolerate and were associated with adverse side-effects, such as the risk of rejection. With the advent of oral directly acting antiviral therapies, the landscape for HCV and transplantation has changed. These agents are highly effective and well tolerated with minimal side-effects. Sustained viral response rates in excess of 90% are achieved with most current treatment regimens active against all HCV genotypes. These new agents may show an improvement in graft and patient survival while essentially eliminating the risk of acute rejection from the use of prior interferon-based HCV therapies. These agents may also result in an improvement in organ allocation for HCV donor/HCV recipient transplantation. This review is meant to discuss the epidemiology of HCV, the new oral direct-acting antiviral agents (DAAs) and future opportunities for research in the field of HCV related transplantation.

Timing of hepatitis C virus infection treatment in kidney transplant candidates

Hepatitis C virus (HCV) infection is prevalent in patients with kidney disease including transplant candidates and recipients. It is associated with increased morbidity and mortality in end-stage renal disease patients and also increases the risk of allograft rejection and decreases allograft and patient survival post-transplant. Newly developed direct acting antivirals have revolutionized the way HCV is treated. Whether patients are treated before or after kidney transplantation, the cure rates with direct acting antivirals are >90%. Great debate has formed revolving the optimal timing to treat kidney transplant candidates. On the one hand, treatment before transplantation decreases early post-transplant complications related to HCV. On the other, postponing treatment until after transplantation opens the possibility of transplanting a kidney from a HCV positive donor, which is associated with shorter waiting time and improved organ utilization by expanding the organ donor pool. Most patients living in an area where waiting time is reduced by accepting an HCV positive kidney would benefit by the strategy of treatment post-transplantation, but this decision needs to be individualized in a patient-by-patient basis given that there are special circumstances (i.e., severe HCV-related extrahepatic manifestations, availability of live donors, etc.) in which treatment before transplant might be preferred.

Low prevalence of occult hepatitis B virus infection in chronic haemodialysis and kidney transplant patients

BACKGROUND

Occult hepatitis B virus infection (OBI) is defined as the presence of hepatitis B virus (HBV) DNA in serum and/or liver in HBsAg-negative patients. We investigated the prevalence of OBI in large chronic haemodialysis (CHD) and kidney transplant recipients (KTxR) cohorts, including determination of HBV DNA in peripheral blood mononuclear cells (PBMCs).

METHODS

HBV DNA was determined in both serum and PBMCs in 417 CHD patients, 417 KTxR, 20 HBsAg-positive non-CHD non-KTx patients (positive controls) and 40 HBsAg-negative healthy subjects (negative controls).

RESULTS

Chronic haemodialysis group: two of 376 patients were HBsAg-positive. The 374 HBsAg-negative patients tested negative for HBV DNA in both serum and PBMCs. KTxR group: 14 of 417 patients were HBsAg-positive. One of 403 HBsAg-negative patients tested positive for HBV DNA in serum but not in PBMCs. Positive controls: six of 20 patients were under antiviral therapy and had negative HBV DNA in both serum and PBMCs. In 11 of 14 remaining patients, HBV DNA was detected in serum and in both serum and PBMCs in 3 patients. Negative controls: All 34 patients were anti-HBc-negative and HBV DNA-negative in both serum and PBMCs. In the long term, the only case of anti-HBc-negative OBI lost anti-HBs 5 years after inclusion in the study and showed HBV reactivation with HBsAg re-seroconversion.

CONCLUSIONS

We found nil prevalence of OBI in CHD patients and a very low prevalence (<1%) in KTxR suggesting that routine screening for HBV DNA is not required in CHD population in our region. However, in KTxR, pretransplant screening with HBV DNA should be considered. Testing for HBV DNA in PBMCs does not seem to be of additional value.

Significance of Occult Hepatitis C Virus Infection in Liver Transplant Patients With Cryptogenic Cirrhosis

OBJECTIVES

Investigations into the viral causes of end-stage liver disease in liver transplant patients with cryptogenic underlying disease remain of interest. Hepatitis C virus infection, especially in its silent (occult) form, may play a key role in the introduction and development of cryptogenic cirrhosis. We aimed to determine the prevalence of occult hepatitis C virus infection in liver transplant recipients with cryptogenic cirrhosis.

MATERIALS AND METHODS

In this cross-sectional study, 127 liver transplant recipients confirmed to have cryptogenic cirrhosis were included. Plasma samples of the patients underwent evaluation for hepatitis C virus antibody using the enzyme-linked immunosorbent assay method. Plasma samples and paraffin-embedded liver tissue samples were tested for hepatitis C virus RNA using nested reverse transcriptase-polymerase chain reaction.

RESULTS

Hepatitis C virus RNA was detected in liver tissue sections of 10 patients (7.9%). However, none of the cryptogenic patients had hepatitis C virus RNA or antibody in their plasma samples. None of the patients had hepatitis C or G virus coinfection, but simultaneous detection of hepatitis B and hepatitis C virus was diagnosed in 4 liver tissue samples.

CONCLUSIONS

A finding of hepatitis C virus RNA in liver tissue samples of transplant recipients presents the historical possibility of occult hepatitis C virus infection as underlying disease in our patients with cryptogenic cirrhosis. Results present an important and determinative role of occult hepatitis C virus infection in the pathogenesis of cryptogenic cirrhosis, which needs further confirmation in additional studies.

Occult Hepatitis C Infection Among Hemodialysis Patients: A Prevalence Study

INTRODUCTION AND AIM

Occult hepatitis C infection (OHCI) is the presence of HCV-RNA in the liver or peripheral blood mononuclear cells (PBMC) accompanying with negative serologic results. The aim of this study was to evaluate the prevalence of OHCI among Iranian chronic hemodialysis (HD) patients.

MATERIAL AND METHODS

In this cross sectional study 200 chronic HD patients with negative HCV antibody enrolled the study. Blood sample of patients were obtained, followed by Polymerase Chain reaction (PCR) testing for detection of HCV RNA. Patients with positive serum HCV RNA were considered as manifest hepatitis C infection (MHCI). However, patients with negative serum HCV RNA underwent further tests on PBMCs for detection of OHCI.

RESULTS

Serum HCV RNA was positive in 2 (1%) patients whom considered as MHCI, and 6 (3.03%) patients had positive PBMC HCV RNA.

CONCLUSION

In conclusion, chronic HD patients have been considered as a high risk group for hepatitis C infection. The results of this study suggest that these patients are also at risk for OHCI. Furthermore, evaluating PBMCs to detect HCV RNA would be a sensitive diagnostic method to find OHCI patients.

Prevalence of occult hepatitis C virus among hemodialysis patients in Tanta university hospitals: a single-center study

Occult hepatitis C virus infection (OCI) is a newly defined type of infection by the chronic hepatitis virus (HCV) distinguished by the existence of HCV RNA in liver tissue and/or peripheral blood mononuclear cells (PBMCs) in patients whose plasma are devoid of both positive serology and RNA. Patients on maintenance hemodialysis evince a higher HCV prevalence than the general population due to high nosocomial transmission by the dialysis units. We investigated the prevalence of occult HCV infection in patients attending our university hemodialysis centers for maintenance hemodialysis. Sixty-two CHD patients negative for serum HCV tests were enrolled in the study. PMNCs were tested by real-time PCR for the presence of HCV RNA. For the 62 patients, the average duration since starting dialysis was 32.7 months and the mean (SD) alanine transaminase and aspartate transaminase were 25.74 ± 9.75 and 28.81 ± 11.32 IU/l, respectively. Out of the 62 CHD patients negative for serum anti-HCV and HCV RNA patients, only three (4.84%) were shown to have HCV RNA in their PBMCs implying the diagnosis of OCI; their viral load range was 1.24-4.15 IU/ml. All three OCI-proven patients gave no history of hepatic disease. In this study, we found that patients considered to be free of HCV can have HCV replicating in their PBMCs. This awareness points to the possibility of HCV being transmitted from apparently uninfected persons. A positive HCV RNA detection in PBMCs is dependable in determining OCI among high-risk subjects particularly when a liver biopsy is not an option. HCV transmission can occur through hemodialysis units signaling incorrect application of infection control measures in our Egyptian dialysis units. Additional studies on hemodialysis patients are necessary to realize the true magnitude of OCI among this patient group and to highlight the importance of incorporating HCV viral assays in PBMCs into the diagnostic algorithm.

Direct-acting antiviral therapy for hepatitis C virus infection in the kidney transplant recipient

Hepatitis C virus infection (HCV) is a common comorbidity in patients who have undergone kidney transplantation and is associated with increased morbidity and mortality compared with recipients who do not have chronic HCV infection. Because interferon-α-based therapies can precipitate acute rejection, they are relatively contraindicated after kidney transplantation. Thus, the majority of kidney transplant recipients with HCV remain untreated. There are now all-oral, interferon-free direct-acting antiviral therapies for HCV infection that are extremely effective and well tolerated in the general population. Recent reports in the literature demonstrate that direct-acting antiviral therapies effectively cured HCV in 406 of 418 kidney transplant recipients (97%); the majority were treated with sofosbuvir-based regimens. Smaller numbers of kidney transplant recipients have been treated with paritaprevir-ritonavir, ombitasvir and dasabuvir, elbasvir-grazoprevir, or glecaprevir-pibrentasvir with excellent success. Direct-acting antiviral therapies were well tolerated and did not increase the rate of acute rejection. The latest advances include approval of regimens that can treat patients with advanced allograft dysfunction (eGFR < 30 ml/min per 1.73 m²) and "pan-genotypic" regimens that have activity against all 6 major genotypes of HCV. This review summarizes what is known about the epidemiology of HCV infection in kidney transplant recipients, and presents the landscape of direct-acting antiviral therapies and areas in need of further investigation.

Occult HCV Infection (OCI) Diagnosis in Cirrhotic and Non-cirrhotic Naïve Patients by Intra-PBMC Nested Viral RNA PCR

Background and Aims: Occult HCV infections (OCIs) include IgG antibody seronegative cryptogenic (COCIs), as well as seropositive secondary naïve (SNOCIs) and experienced (SEOCIs) cases. We used peripheral-blood-mononuclear-cell (PBMC)-PCR to evaluate COCIs and SNOCIs prevalence, serum HCV spontaneous disappearance (SCSD) in naïve cirrhotics and non-cirrhotics, intra-PBMC HCV-RNA strands in relation to cirrhosis density in naïve non-viremia cases, and HCV-RNA seroconversion after 1 year of solitary naïve intra-PBMC infection. Methods: The anti-HCV IgG antibody-positive naïve-patients (n = 785) were classified into viremic (n = 673) and non-viremic [n = 112, including non-cirrhotics (n = 55) and cirrhotics (n = 57)], and 62 controls without evidence of HCV-infection. Controls and post-HCV non-viremia cases (n = 62+112 = 174) were submitted to hepatic Fibroscan-Elastography evaluation. All subjects (n = 847) were screened for intra-PBMC HCV-RNA sense and antisense strands by nested-PCR. Results: Naïve-OCI cases (4.84%) that were diagnosed by PBMC-PCR significantly raised the total numbers of HCV-infection to 714 (p = 0.01). The percent positivity of SNOCIs (34.82%) was significantly higher than for asymptomatic-COCIs (3.125%, p = 0.0001). Comparing PBMC-PCR with single-step-reverse-transcription (SRT)-PCR for identification of SCSD in naïve IgG antibody-positive non-viremia patients (n = 112) revealed a decline in SCSD prevalence by PBMC-PCR (from 14.27% to 9.3%), regardless of presence of hepatic cirrhosis (p = 0.03). SCSD was found to be higher by PBMC-PCR in non-cirrhotics compared to cirrhotics (p = 0.0001), with an insignificant difference when using SRT-PCR (p = 0.45). Intra-PBMC HCV-RNA infection was significantly more frequent in cirrhotics compared to both non-cirrhotics and controls (p < 0.0005). An increased hepatic fibrosis density was recognized in intra-PBMC HCV-RNA infection with sense (p = 0.0001) or antisense strand (p = 0.003). HCV-RNA seroconversion was associated with intra-PBMC infection when both sense and antisense strands were detected (p = 0.047). Conclusions: Intracellular HCV-RNA evaluation is crucial for diagnosing OCIs and addressing relapse probability.

Diagnostic Dilemmas in Hepatitis C Virus Infection for Hemodialysis Patients

BACKGROUND

Hepatitis C virus (HCV) is a leading cause of chronic hepatitis in dialysis patients. The diagnosis of HCV infection in these patients is predominantly based on laboratory tests because of the specificity of the clinical course of the disease.

AIM

The present prospective study aimed at determining very accurately the prevalence rate of HCV infection in patients on dialysis by simultaneously testing them for anti-HCV and for HCV RNA levels.

MATERIALS AND METHODS

For the present cross-sectional longitudinal study we recruited and followed up 93 patients from St George University Hospital Hemodialysis Unit between July 2013 and December 2014. All patients were tested for anti-HCV and HCV RNA. The anti-HCV negative patients were tested for anti-HCV and HCV RNA at least twice at intervals of 6 months or more (up to 12 months). Anti-HCV antibodies were identified using a third generation ELISA assay. Commercial kits for real-time polymerase chain reaction (RT-PCR) were used to detect HCV RNA in the plasma and mononuclear cells. Aminotransferase and gammaglutamyl transpeptidase levels were studied to find if liver inflammation was present.

RESULTS

The total seroprevalence in 68 patients was 20.6% (14). Of these, 10 patients were viremic (HCV RNA+/anti-HCV+), and 4 patients (5.9%) had discordant results (anti-HCV+/HCV RNA-). Acute hepatitis was detected in one patient. Duration of dialysis in HCV viremic patients was longer than that in aviremic patients (p=0.005).

CONCLUSIONS

The present study suggests that HCV infection in dialysis patients can be diagnosed more accurately if these patients are tested using two diagnostic methods - a serological test and a biomolecular assay. Further studies with larger sample size may prove the feasibility of such approach for all dialysis patients in this country.

Occult hepatitis C virus infection among Egyptian hemodialysis patients

Occult hepatitis C virus (HCV) infection (OCI) was reported in an apparently disease-free state in the absence of liver disease, anti-HCV and HCV-RNA in the serum. The existing data examining the clinical significance of OCI and its potential as a source of HCV infection among hemodialysis patients are very limited. We examined the presence of OCI among patients on maintenance hemodialysis at Minia Governorate, Egypt; an HCV endemic country. A total of 81 subjects with negative markers for HCV were enrolled. HCV-RNA was tested in PBMCs by real-time PCR. For the 81 subjects, the average dialysis duration was 32.7 ± 21.7 months and the average ALT level (±SD) was 26 ± 12 U/L while that of AST was 29 ± 16 U/L. Out of the 81 subjects, three (3.7%) were HCV-RNA positive in PBMCs in the absence of serum anti-HCV and HCV-RNA indicating OCI. The viral load of the OCI subjects ranged from 172 to 4150 IU/ml. History of liver disease was positive in one of the three positive patients. These results highlight the potential risk of HCV transmission from patients within hemodialysis units in Egypt. J. Med. Virol. 88:1388-1393, 2016. © 2016 Wiley Periodicals, Inc.

Prevalence of occult hepatitis C virus infection in the Iranian patients with human immunodeficiency virus infection

Occult hepatitis C virus (HCV) infection is a new form of chronic HCV infection described by the presence of the genomic HCV-RNA in liver biopsy and/or peripheral blood mononuclear cell (PBMC) samples, and undetectable levels or absence of HCV-RNA and in the absence or presence of anti HCV antibodies in the plasma specimens. The aim of the present study was to evaluate the occurrence of occult HCV infection (OCI) among Iranian subjects infected with human immunodeficiency virus (HIV) using RT-nested PCR. From March 2014 until April 2015, 109 Iranian patients with established HIV infection were enrolled in this cross-sectional study. After extraction of viral RNA from the plasma and PBMC samples, HCV-RNA status was examined by RT-nested PCR using primers from the 5'-NTR. HCV genotyping was conducted using RFLP analysis. For the confirmation of HCV genotyping by RFLP method, the PCR products were sequenced. Of the 109 patients, 50 were positive for antibodies against HCV. The HCV-RNA was detected in PBMC specimens in 6 (10.2%) out of the total 59 patients negative for anti-HCV Abs and undetectable plasma HCV-RNA and also from 4 (8.0%) out of the total 50 patients positive for anti-HCV Abs and undetectable plasma HCV-RNA. HCV genotyping analysis showed that 6 (60.0%) patients were infected with HCV subtype 3a, 3 (30.0%) were infected with HCV subtype 1a and 1 (10.0%) patient was infected with HCV subtype 1b. This study revealed the incidence of OCI (9.2%) in HIV-infected Iranian patients. Hence, designing prospective studies focusing on the detection of OCI in these patients would provide more information. J. Med. Virol. 88:1960-1966, 2016. © 2016 Wiley Periodicals, Inc.

Prevalence of occult hepatitis C virus infection in Iranian patients with beta thalassemia major

Occult hepatitis C virus infection (OCI) is a new pathological form of chronic hepatitis virus (HCV) infection characterized by the presence of HCV RNA in liver biopsy and/or peripheral blood mononuclear cell (PBMC) specimens and the absence of HCV RNA and anti-HCV antibodies (Abs) in plasma samples. β-thalassemia major is a hereditary recessive blood disease with deficiency in the hemoglobin beta chain. Thalassemic patients need blood transfusion therapy; repeated blood transfusion increases the risk of viral blood-borne infection. The aim of this study was to determine the prevalence of OCI in Iranian patients with β-thalassemia major. From February 2015 to November 2015, a total of 147 Iranian patients with β-thalassemia major were enrolled in this cross-sectional study. After extraction of viral RNA from the plasma and PBMC samples, HCV genomic RNA in the specimens was amplified by RT-nested PCR using primers from the 5'-UTR. The HCV genotypes of the positive specimens were tested using the RFLP assay. To confirm the HCV genotypes, the 5'-UTR fragment was amplified and cloned into the pJET1.2/blunt cloning vector and then sequenced. Out of 147 patients, 106 (72.1 %) were negative for anti-HCV Abs and HCV RNA. HCV RNA was found in PBMC specimens of six (5.7 %) patients, from a total of 106 patients with undetectable plasma HCV RNA and anti-HCV Abs. Therefore, six out of 106 patients had OCI. HCV genotyping revealed that three patients were infected with HCV subtype 1b, two patients were infected with HCV subtype 3a, and one patient was infected with HCV subtype 1a. These results revealed that Iranian patients with beta-thalassemia major might have OCI. Therefore, it seems that the design of a study to identify this infection in patients with β-thalassemia major would provide valuable information.

Pharmacokinetics, safety and efficacy of a full dose sofosbuvir-based regimen given daily in hemodialysis patients with chronic hepatitis C

BACKGROUND & AIMS

Hepatitis C virus (HCV) infection is an independent risk factor for chronic kidney disease and leads to faster liver disease progression in patients requiring hemodialysis than in those with normal renal function. Little is known about the use of a sofosbuvir-containing regimen for infected patients on hemodialysis. We aimed to describe the pharmacokinetics, safety and efficacy of sofosbuvir in 2 dosing regimens and associated antiviral agents in HCV-infected patients requiring hemodialysis.

METHODS

Multicenter, prospective and observational study of patients receiving sofosbuvir, 400mg once daily (n=7) or 3 times a week (n=5), after hemodialysis with simeprevir, daclatasvir, ledipasvir or ribavirin was conducted. Drug plasma concentrations were determined by liquid chromatography-tandem mass spectrometry before and after a 4h hemodialysis and 1.5h after last drug intake at the end of hemodialysis.

RESULTS

Plasma concentrations of sofosbuvir or its inactive metabolite sofosbuvir-007 did not accumulate with either regimen between hemodialysis sessions or throughout the treatment course. Sofosbuvir-007 extraction ratio (52%) was consistent with historical data. In one patient receiving the once daily regimen, sofosbuvir-007 half-life was slightly higher (38h) than for patients with normal renal function receiving a full dose. Hemodialysis did not remove any other associated anti-HCV agents. Clinical and biological tolerance was good for all patients. Two relapses occurred with the 3 times a week regimen and none with the once daily.

CONCLUSIONS

A regimen including sofosbuvir, 400mg once daily, could be proposed for HCV-infected patients requiring hemodialysis and should be associated with close clinical, biological, cardiovascular, and therapeutic drug monitoring.

LAY SUMMARY

Hepatitis C Virus (HCV) infection in hemodialysis patients is prevalent and aggressive. Effective anti-HCV treatment in these patients may stabilize their renal disease. However, sofosbuvir, the cornerstone of most anti-HCV-containing regimens, should not be administered to these patients until more data is available. In this pharmacokinetic study, sofosbuvir full dose (400mg once daily) administered every day with another direct antiviral agent did not accumulate in hemodialysis patients and was safe and effective.

Epidemiological Aspects of Hepatitis B and C and Human Immunodeficiency Viruses Among Hemodialysis Patients in Mazandaran Province, Iran

BACKGROUND

Hemodialysis patients are potentially susceptible to infection with blood-borne viral agents, especially hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV).

OBJECTIVES

The aim of this study was to evaluate the prevalence and incidence of HBV, HCV, and HIV infections in hemodialysis patients.

PATIENTS AND METHODS

This study was carried out in 482 hemodialysis patients who had been referred to eight dialysis centers in the Mazandaran province in Iran from 2012 - 2014. HBs Ag, HCV Ab, HBs Ab and HIV Ab were assessed every three months for two years. The patients' demographic characteristics, including age, gender, area of residence, and duration of dialysis, were noted. The prevalence of each virus was also determined.

RESULTS

From a total of 482 patients, 253 (52.5%) males and 229 (47.5%) females were evaluated. The mean age of all patients was 54.96 ± 16.1 years, and all participants were HIV negative. One subject had both HBV and HCV infections. HBs Ag and anti-HCV were detected in 10 (2.1%) and 40 (8.27%) patients, respectively. The mean age of HCV-positive patients was 55.4 ± 16.4, while HCV-negative patients were an average of 51.6 ± 10.7 years old (P = 0.002). The incidence of HCV was higher in people from 40-59 years of age (P < 0.001). No patients had HBV, and incidence of HCV was 0.5% in the first year and 0.75 in the second year. No cases of HIV were identified.

CONCLUSIONS

The results show that the prevalence rates of HBV and HCV in hemodialysis patients were moderate to low in the Mazandaran province. Based upon the obtained levels of these viruses, these incidence rates are therefore reasonable.

Decreasing Hepatitis C Virus Infection in Thailand in the Past Decade: Evidence from the 2014 National Survey

Hepatitis C virus (HCV) infection affects ≥ 180 million individuals worldwide especially those living in developing countries. Recent advances in direct-acting therapeutics promise effective treatments for chronic HCV carriers, but only if the affected individuals are identified. Good treatment coverage therefore requires accurate epidemiological data on HCV infection. In 2014, we determined the current prevalence of HCV in Thailand to assess whether over the past decade the significant number of chronic carriers had changed. In total, 5964 serum samples from Thai residents between 6 months and 71 years of age were obtained from 7 provinces representing all 4 geographical regions of Thailand and screened for the anti-HCV antibody. Positive samples were further analyzed using RT-PCR, sequencing, and phylogenetic analysis to identify the prevailing HCV genotypes. We found that 56 (0.94%) samples tested positive for anti-HCV antibody (mean age = 36.6±17.6 years), while HCV RNA of the core and NS5B subgenomic regions was detected in 23 (41%) and 19 (34%) of the samples, respectively. The seropositive rates appeared to increase with age and peaked in individuals 41-50 years old. These results suggested that approximately 759,000 individuals are currently anti-HCV-positive and that 357,000 individuals have viremic HCV infection. These numbers represent a significant decline in the prevalence of HCV infection. Interestingly, the frequency of genotype 6 variants increased from 8.9% to 34.8%, while the prevalence of genotype 1b declined from 27% to 13%. These most recent comprehensive estimates of HCV burden in Thailand are valuable towards evidence-based treatment coverage for specific population groups, appropriate allocation of resources, and improvement in the national public health policy.

Occult Hepatitis C Virus Infection in Hemodialysis Patients; Single Center Study

INTRODUCTION

A new form of hepatitis C virus infection, known as occult hepatitis C virus (HCV) infection, is characterized by the presence of HCV_RNA in the liver or peripheral blood mononuclear cells (PBMCs). However, no serological markers of infection occur and there is not as much damage to the liver damage as is produced by chronic hepatitis C. There is a high incidence of HCV infection among hemodialysis patients, there is significant concern about viral transmission. HCV infection is a major problem in hemodialysis (HD) units even though blood products are screened for anti-HCV antibodies and other precautions are taken. The aim of this study was to determine the prevalence of occult HCV infection in PBMC in chronic hemodialysis (CHD) patients in the dialysis unit at Theodor Bilharz Research Institute (TBRI) with HCV antibodies and HCV RNA negativity irrespective of their liver function tests.

METHODS

Fifty-three patients who were repeatedly were anti-HCV negative and serum HCV-RNA negative and on regular hemodialysis for > six months were enrolled in the study, which was conducted in the dialysis unit of Nephrology Department at TBRI; there were 10 healthy matched controls. The patients were classified into two groups according to the result HCV RNA in their PBMCs. Serological markers of HCV infection, including anti-HCV antibody and serum HCV-RNA, were repeatedly negative for all patients included in the study. We collected serum and PBMC samples from the patients on the day they entered the study. The test of all serum samples for anti-HCV antibodies and HCV-RNA was repeated by RT-PCR to ensure that the patients did not have these HCV serologic markers, We also measured their ALT and GGT levels.

RESULTS

Occult hepatitis C virus infection (OCI) was detected in 15.1% of our CHD patients without any evidence of chronic liver disease.

CONCLUSION

Occult HCV infection was present among the hemodialysis patients irrespective of whether they had persistent abnormal values of liver enzymes for which no cause had been identified. Further study is required to determine the clinical significance of occult HCV infections in these patients.

Occult HCV Infection: The Current State of Knowledge

CONTEXT

Occult HCV infection (OCI) is defined as the presence of HCV-RNA in hepatocytes and the absence of HCV in the serum according to usual tests. We aimed to define OCI and provide information about the currently available diagnostic methods. Then we focus on specific groups that are at high risk of OCI and finally investigate immune responses to OCI and the available treatment approaches.

EVIDENCE ACQUISITION

PubMed, Scopus and Google Scholar were comprehensively searched with combination of following keywords: "occult", "hepatitis C virus" and "occult HCV infection". The definition of OCI, diagnostic methods, specific groups that are at high risk and available treatment approaches were extract from literature. An analysis of available articles on OCI also was done based on Scopus search results.

RESULTS

OCI has been reported in several high-risk groups, especially in hemodialysis patients and subjects with cryptogenic liver disease. Furthermore, some studies have proposed a specific immune response for OCI in comparison with chronic hepatitis C (CHC).

CONCLUSIONS

With a clinical history of approximately 11 years, occult HCV infection can be considered an occult type of CHC. Evidences suggest that considering OCI in these high-risk groups seems to be necessary. We suggest that alternative diagnostic tests should be applied and that there is a need for the participation of all countries to determine the epidemiology of this type of HCV infection. Additionally, evaluating OCI in blood transfusion centers and in patients who receive large amounts of blood and clotting factors, such as patients with hemophilia, should be performed in future projects.

A New Twist to a Chronic HCV Infection: Occult Hepatitis C

Background. The prevalence of occult hepatitis C infection (OCI) in the population of HCV-RNA negative but anti-HCV positive individuals is presently unknown. OCI may be responsible for clinically overt recurrent disease following an apparent sustained viral response (SVR) weeks to years later. Purpose. To review the available current literature regarding OCI, prevalence, pathogenic mechanisms, clinical characteristics, and future directions. Data Sources. Searching MEDLINE, article references, and national and international meeting abstracts for the diagnosis of OCI (1990-2014). Data Synthesis. The long-term followup of individuals with an OCI suggests that the infection can be transient with the loss of detectable HCV-RNA in PPBMCs after 12-18 months or alternatively exist intermittently and potentially long term. The ultimate outcome of HCV infection is decided by interplay between host immune responses, antiviral therapies, and the various well-identified viral evasion mechanisms as well as the presence of HCV infection within extrahepatic tissues. Conclusion. The currently widely held assumption of a HCV-cure in individuals having had "SVR" after 8-12 weeks of a course of DAA therapy as recently defined may not be entirely valid. Careful longitudinal followup utilizing highly sensitive assays and unique approaches to viral isolation are needed.

Management of hepatitis C in patients with chronic kidney disease

Hepatitis C virus (HCV) infection is highly prevalent among chronic kidney disease (CKD) subjects under hemodialysis and in kidney transplantation (KT) recipients, being an important cause of morbidity and mortality in these patients. The vast majority of HCV chronic infections in the hemodialysis setting are currently attributable to nosocomial transmission. Acute and chronic hepatitis C exhibits distinct clinical and laboratorial features, which can impact on management and treatment decisions. In hemodialysis subjects, acute infections are usually asymptomatic and anicteric; since spontaneous viral clearance is very uncommon in this context, acute infections should be treated as soon as possible. In KT recipients, the occurrence of acute hepatitis C can have a more severe course, with a rapid progression of liver fibrosis. In these patients, it is recommended to use pegylated interferon (PEG-IFN) in combination with ribavirin, with doses adjusted according to estimated glomerular filtration rate. There is no evidence suggesting that chronic hepatitis C exhibits a more aggressive course in CKD subjects under conservative management. In these subjects, indication of treatment with PEG-IFN plus ribavirin relies on the CKD stage, rate of progression of renal dysfunction and the possibility of a preemptive transplant. HCV infection has been associated with both liver disease-related deaths and cardiovascular mortality in hemodialysis patients. Among those individuals, low HCV viral loads and the phenomenon of intermittent HCV viremia are often observed, and sequential HCV RNA monitoring is needed. Despite the poor tolerability and suboptimal efficacy of antiviral therapy in CKD patients, many patients can achieve sustained virological response, which improve patient and graft outcomes. Hepatitis C eradication before KT theoretically improves survival and reduces the occurrence of chronic graft nephropathy, de novo glomerulonephritis and post-transplant diabetes mellitus.

Hepatitis C virus infection and kidney transplantation in 2014: what's new?

Chronic hepatitis C virus (HCV) infection remains an important health problem, which is associated with deleterious consequences in kidney transplant recipients. Besides hepatic complications, several extrahepatic complications contribute to reduced patient and allograft survival in HCV-infected kidney recipients. However, HCV infection should not be considered as a contraindication for kidney transplantation because patient survival is better with transplantation than on dialysis. Treatment of HCV infection is currently interferon-alpha (IFN-α) based, which has been associated with higher renal allograft rejection rates. Therefore, antiviral treatment before transplantation is preferable. As in the nontransplant setting, IFN-free treatment regimens, because of their greater efficacy and reduced toxicity, currently represent promising and attractive therapeutic options after kidney transplantation as well. However, clinical trials will be required to closely evaluate these regimens in kidney recipients. There is also a need for prospective controlled studies to determine the optimal immunosuppressive regimens after transplantation in HCV-infected recipients. Combined kidney and liver transplantation is required in patients with advanced liver cirrhosis. However, in patients with cleared HCV infection and early cirrhosis without portal hypertension, kidney transplantation alone may be considered. There is some agreement about the use of HCV-positive donors in HCV-infected recipients, although data regarding posttransplant survival rates are controversial.

Seronegative occult hepatitis C virus infection: clinical implications

Occult hepatitis C virus infection (OCI) was first described in anti-HCV and serum HCV-RNA negative patients with abnormal values of liver enzymes but who presented HCV-RNA in liver and in peripheral blood mononuclear cells. Up to now, two types of OCI are recognized: seronegative OCI (anti-HCV and serum HCV-RNA negative) and seropositive OCI (anti-HCV positive and serum HCV-RNA negative). The concept of OCI is still a matter of debate, probably because both types of OCI are not considered as different entities. This review focuses on seronegative OCI. The existence of seronegative OCI has been documented all around the world with the implication of different HCV genotypes (1-4). Seronegative OCI is associated with cryptogenic chronic hepatitis and liver cirrhosis and it may be involved in the appearance of hepatocellular carcinoma. Also seronegative OCI may increase the histological liver damage in chronic hepatitis B and in HIV-infected patients. It may have a negative influence in the natural history of hemodialysis patients and in immune-mediated glomerulonephritis. Seronegative OCI has been detected also in patients with haematological diseases, among healthy subjects and in drug users. Other publications indicate the potential infectivity of seronegative OCI in the setting of family members, sexual partners and liver transplantation. In summary, seronegative OCI may play a role in liver diseases and other human pathologies and may be present in healthy people but larger studies are needed to confirm these findings.