Prevalence and follow-up of occult HCV infection in an Italian population free of clinically detectable infectious liver disease

Global prevalence of occult hepatitis C virus: A systematic review and meta-analysis

BACKGROUND

Occult hepatitis C infection (OCI) is characterized by the presence of hepatitis C virus (HCV) RNA in the liver, peripheral blood mononuclear cells (PBMC) and/or ultracentrifuged serum in the absence of detectable HCV-RNA in serum. OCI has been described in several categories of populations including hemodialysis patients, patients with a sustained virological response, immunocompromised individuals, patients with abnormal hepatic function, and apparently healthy subjects.

AIM

To highlight the global prevalence of OCI.

METHODS

We performed a systematic and comprehensive literature search in the following 4 electronic databases PubMed, EMBASE, Global Index Medicus, and Web of Science up to 6th May 2021 to retrieve relevant studies published in the field. Included studies were unrestricted population categories with known RNA status in serum, PBMC, liver tissue and/or ultracentrifuged serum. Data were extracted independently by each author and the Hoy et al tool was used to assess the quality of the included studies. We used the random-effect meta-analysis model to estimate the proportions of OCI and their 95% confidence intervals (95%CI). The Cochran's Q-test and the I² test statistics were used to assess heterogeneity between studies. Funnel plot and Egger test were used to examine publication bias. R software version 4.1.0 was used for all analyses.

RESULTS

The electronic search resulted in 3950 articles. We obtained 102 prevalence data from 85 included studies. The pooled prevalence of seronegative OCI was estimated to be 9.61% (95%CI: 6.84-12.73) with substantial heterogeneity [I² = 94.7% (95%CI: 93.8%-95.4%), P < 0.0001]. Seropositive OCI prevalence was estimated to be 13.39% (95%CI: 7.85-19.99) with substantial heterogeneity [I² = 93.0% (90.8%-94.7%)]. Higher seronegative OCI prevalence was found in Southern Europe and Northern Africa, and in patients with abnormal liver function, hematological disorders, and kidney diseases. Higher seropositive OCI prevalence was found in Southern Europe, Northern America, and Northern Africa.

CONCLUSION

In conclusion, in the present study, it appears that the burden of OCI is high and variable across the different regions and population categories. Further studies on OCI are needed to assess the transmissibility, clinical significance, long-term outcome, and need for treatment.

Prevalence of Occult Hepatitis C Virus Infection in Egyptian Patients with Lymphoma: A New Vision

Occult hepatitis C virus infection (OCI) is the absence of HCV RNA in serum and the presence of actively replicating HCV RNA in hepatocytes and peripheral blood mononuclear cells (PBMCs), as evidenced by the presence of antigenomic negative sense single-stranded RNA. This study aimed to determine the prevalence of OCI in Egyptian lymphoma patients and assess changes in biochemical parameters in patients with confirmed OCI. The current study was conducted on 100 apparently healthy subjects as control group and 100 patients with lymphoma as a case group. HCV RNA was extracted and detected in both plasma and PBMCs using qRT-PCR. Total protein, albumin, ALT, AST, and total and direct bilirubin were measured in serum. OCI was detected in 6% of the patient group. OCI patients had lower levels of total protein and serum albumin and higher ALT and AST compared with lymphoma patients without OCI. Our study revealed that six out of 100 patients with lymphoma disorders had occult HCV infection (6%). Therefore, the possibility of this infection should be considered in patients with lymphoma.

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.

Fatal Hepatitis C after Chemotherapy in a Patient with Malignant Lymphoma: Possible Reactivation of Seronegative Occult Hepatitis C Virus Infection Due to Chemotherapy

A 79-year-old man with lymphoma who tested negative for anti-hepatitis C virus (HCV) antibody received rituximab-containing chemotherapy. Liver dysfunction of unknown cause had persisted since the second cycle of chemotherapy. Ten months after treatment, he rapidly developed massive ascites and atrophy of the liver, and we detected HCV RNA in his serum using real time polymerase chain reaction. Furthermore, medical interviews showed that the patient had no episodes for acute HCV infection, but he did have a history of unspecified liver dysfunction. These findings support the possibility of the reactivation of seronegative occult HCV infection due to chemotherapy in a cancer patient.

Prevalence of occult hepatitis C virus infection in hemodialysis patients

BACKGROUND

Via hemodialysis, viral infections can be transmitted in patients a new definition of this infection with no increase in liver enzymes, negative HCV-PCR in serum and presence of virus in the liver and peripheral blood mononuclear cell (PBMC) called occult hepatitis C virus (HCV) infection (OCI). We decided to examine the prevalence of occult hepatitis C infection on hemodialysis cases.

METHODS

The current research is a cross-sectional study on patients with end-stage renal disease (ESRD) who were at three hemodialysis centers in Mazandaran province in Iran during 2012-2014. In this study of 356 patients who were undergoing hemodialysis, 54 patients were excluded due to positive HCV Ab, and the remaining 302 patients were enrolled. The test of all serum samples for HCV-RNA detection of plasma and PBMCs was done by real-time polymerase chain reaction (real-time PCR).

RESULTS

There was a significant association between the duration of dialysis with the prevalence of occult HCV infection (P=0.017). Eight (2.65%) patients were positive for HBs Ag and with OCI, but none of them was infected with both hepatitis C and B obviously. Also among the total number of patients, nine patients tested positive for HCV RT-PCR in PBMC in which one of them was positive for serum HCV RNA PCR and was excluded from the study.

CONCLUSION

The results showed that eight patients had an OCI. There was not any association found between age and sex with OCI, but there was a significant relationship between the duration of dialysis with the prevalence of OCI.

Occult HCV and occult HBV coinfection in Iranian human immunodeficiency virus-infected individuals

The presence of hepatitis C virus (HCV) genome in liver biopsy or peripheral blood mononuclear cell (PBMC) specimens in the absence of detectable HCV-RNA in plasma of the people with or without anti-HCV antibodies has defined as occult HCV infection (OCI), whereas occult hepatitis B virus infection (OBI) is detection of hepatitis B virus (HBV) genome in the absence of traceable hepatitis B surface antigen in the plasma samples of patients. The purpose of this study is to determine the presence of OBI and OCI in human immunodeficiency virus (HIV)-infected individuals. In this cross-sectional research, 190 Iranian HIV-infected individuals were enrolled from September 2015 to February 2019. All participants were tested regarding various serological markers for HCV and HBV infections. Viral RNA and DNA were extracted from plasma and PBMC specimens, and the presence of HCV-RNA in plasma and PBMC samples was tested using reverse transcriptase-nested polymerase chain reaction (PCR), HBV viral load was determined in plasma samples using COBAS TaqMan 48 Kit, and also the presence of the HBV-DNA in PBMC samples was tested by real-time PCR. In this study, the prevalence of OBI and OCI in HIV-infected individuals was 3.1% and 11.4%, respectively. The genotypes of HCV in the patients with OCI were as follows: 57.1% were infected with subtype 3a, 35.7% were infected with subtype 1a, and 7.1% was infected with subtype 1b. It is noteworthy that in this study, two patients (1.1%) had OCI/OBI coinfections. The present study revealed that 1.1% of Iranian HIV-infected individuals had OBI and OCI at the same time. Therefore, it seems that designing prospective surveys to determine the presence of this coinfection in HIV-infected individuals is informative.

Understanding occult hepatitis C infection

BACKGROUND

Occult hepatitis C infection (OCI) is a type of hepatitis C virus (HCV) infection, defined as the presence of HCV RNA in hepatocytes or peripheral blood mononuclear cells (PBMCs) and the absence of HCV RNA in serum.

STUDY DESIGN AND METHODS

A literature review was conducted to identify articles that characterized OCI as a disease, including its epidemiology, mode of transmission, pattern of infection, progression, and treatment.

RESULTS

OCI patients experience a milder degree of inflammatory and cirrhotic changes than patients with chronic hepatitis C. OCI is transmissible parenterally both in vivo and in vitro, however the duration and outcome of OCI remains unclear. OCI is most consistently found in patients with previous hepatitis C disease and hemodialysis patients. Beyond the at-risk populations, OCI has also been demonstrated among healthy individuals and blood donors.

CONCLUSIONS

This review summarises our current understanding of OCI and suggests areas for further research to improve our understanding of this phenomenon, including a better understanding of its epidemiology and full clinical course. The current understanding of OCI and its clinical implications remain limited. Further standardized detection methods, ongoing surveillance, and investigation of its potential transmissions are required.

High prevalence of occult hepatitis C virus infection in injection drug users with HIV infection

One of the pathological forms of chronic hepatitis C is occult HCV infection (OCI), in which there is no detectable HCV RNA in plasma specimens but HCV RNA is present in PBMCs and liver biopsy specimens. The aim of this study is to estimate the prevalence of OCI in HIV-positive people who are injection drug users (IDUs). From April 2015 to August 2018, 161 Iranian IDUs with HIV infection enrolled in the study. Viral RNA was extracted from plasma and PBMC samples of participants, and the presence of HCV RNA was examined using RT nested PCR with primers from two conserved regions (5´-UTR and NS5B). HCV genotyping was performed using RFLP and sequencing methods. Of the 161 patients, 134 (83.2%) were positive for anti-HCV antibodies. All 27 patients who were negative for anti-HCV were also negative for HCV RNA in plasma, but five of them (18.5%) were positive for HCV RNA in PBMCs. Importantly, 9 out of 50 patients (18.0%) who apparently had recovered from HCV infection (i.e., were anti-HCV positive and HCV RNA negative) were positive for HCV RNA in PBMCs. Overall, 18.1% of the patients who had no signs of previous HCV infection or had apparently recovered from the disease had OCI. The HCV genotypes of the cases with OCI were as follows: five patients (35.7%) were infected with subtype 1a, eight patients (57.1%) were infected with subtype 3a, and one patient (7.1%) was infected with genotype 4. Thus, it seems that the prevalence of OCI in HIV-positive IDUs is extremely significant in Iran and is likely to delay the global eradication of HCV infection until 2030.

Prevalence and predictors of occult hepatitis C virus infection among Egyptian patients who achieved sustained virologic response to sofosbuvir/daclatasvir therapy: a multi-center study

Background

Occult hepatitis C virus (HCV) infection (OCI) is characterized by the detection of HCV-RNA in non-serum reservoirs, such as peripheral blood mononuclear cells (PBMCs) and/or hepatocytes with undetectable HCV-RNA or antibodies in the serum. In this study, we tried to evaluate the prevalence and possible predictors of OCI in patients who achieved sustained virologic response (SVR) post sofosbuvir/daclatasvir (SOF/DCV) therapy.

Patients and methods

A cross-sectional multicenter study was designed to enroll 1,280 HCV-infected patients who received SOF (400 mg) plus DCV (60 mg) once daily ± ribavirin regimen for 12 weeks and achieved SVR 12 weeks post treatment. They were randomly recruited from three dedicated Egyptian centers for management of HCV. Real-time PCR was performed to detect HCV-RNA in serum and PBMCs and to evaluate the different risk factors pertaining to the existence of OCI.

Results

HCV-RNA was detected in PBMCs of 50 (3.9%) of them. All OCI cases exhibited significant fibrosis score and raised pre-treatment alanine aminotransferase (ALT) levels. Logistic regression analysis comparing OCI with non-OCI revealed that high pre-treatment viral load, raised ALT, advanced fibrosis score, prolonged prothrombin time, low albumin, Child B score, antiviral experienced patients, and raised bilirubin are the most significant predictor for the possibility of OCI presence with Odds Ratio as 7.03, 5.13, 4.4, 2.68, 2.52, 1.9, 1.5, and 1.2, respectively.

Conclusion

In spite of its remote possibility, OCI post SOF/DCV therapy may be present in some cases, and this may entail a re-auditing for the definition of SVR by dual testing in both serum and PBMCs.

Molecular diagnosis of occult hepatitis C virus infection in Iranian injection drug users

Occult HCV infection (OCI) has been described as the presence of hepatitis C virus (HCV) genomic RNA in hepatocytes and/or peripheral blood mononuclear cell (PBMC) specimens and the lack of HCV genomic RNA and anti-HCV antibodies (Abs) in plasma samples. Injection drug users (IDUs) are the most important high-risk group for infection with blood-borne viruses, particularly HCV. The purpose of this study was to determine the presence of OCI in IDUs. A prospective cross-sectional study of 126 consecutive Iranian IDUs was performed from March 2017 to January 2018. PBMCs were separated from blood samples from the participants, and after extraction of the viral RNA from the plasma and PBMC specimens, HCV RNA was detected in the samples using RT-nested PCR by amplification of the 5'-NTR of HCV. HCV genotyping was carried out using restriction a fragment length polymorphism (RFLP) assay. The viral RNA was amplified using RT-nested PCR with specific primers for the NS5B gene, and the PCR products were sequenced to confirm the results obtained by HCV RNA detection and HCV genotyping. Out of the 126 IDUs studied, 105 (83.3%) were negative for anti-HCV Abs and HCV RNA in plasma samples, whereas HCV RNA was detected in the PBMC samples of six (5.7%) participants, indicating that these individuals had OCI. Moreover, HCV genomic RNA was detected in PBMC samples from five (23.8%) of the 21 IDUs studied who were positive for anti-HCV Abs and negative for HCV genomic RNA in plasma specimens. These IDUs also had OCI. The HCV genotypes in the PBMC samples from the subjects with OCI were determined. Six (54.5%) subjects were infected with HCV subtype 3a, and five (45.5%) were infected with HCV subtype 1a. This study showed that 8.7% of the Iranian IDUs had OCI, and therefore, a study focusing on the diagnosis of OCI in these individuals can be valuable and informative.

Occult hepatitis C virus infection among haemodialysis patients

BACKGROUND AND STUDY AIMS

Hepatitis C virus (HCV) infection is a severe problem among patients on maintenance haemodialysis who are at particular risk for blood-borne infections because of prolonged vascular access and potential for exposure to contaminated equipment. Occult hepatitis C virus infection (OCI) is defined as the presence of HCV RNA in liver or peripheral blood mononuclear cells (PBMCs) in the absence of detectable HCV antibody or HCV RNA in the serum. In this study, we aimed to investigate the existence of occult hepatitis C virus infection in PBMCs of haemodialysis (HD) patients in one center. Moreover, we tried to link the condition to risk factors associated with HCV infection in those patients.

PATIENTS AND METHODS

We included 40 patients with renal diseases undergoing regular haemodialysis who were repeatedly anti-HCV negative. HCV RNA detection was tested by Quantitative Real time PCR in serum and PBMCs.

RESULTS

The results of this study revealed that 23% of our haemodialysis patients have occult hepatitis C virus infection. There was a highly significant increase in ALT levels in patients with OCI versus the negative group. Also, there is a significant increase of history of blood transfusion in patients with occult HCV (p = 0.03) while the duration of haemodialysis showed no statistical significant difference between both groups. The viral load of the occult hepatitis C virus infection subjects ranged from 581to 74,307 copies/ml.

CONCLUSION

These results highlight the potential risk of hepatitis C virus transmission from patients within haemodialysis units in Egypt. Isolation of patients on dialysis machines depending on the results of hepatitis serological markers is not enough. Testing for hepatitis C virus -RNA in peripheral blood mononuclear cells is more reliable in identifying patients with an OCI when a liver biopsy is not available.

Occult Hepatitis C Virus Infection: A Review

Occult hepatitis C virus (HCV) infection (OCI), first described in 2004, is defined as the presence of HCV RNA in hepatocytes or peripheral blood mononuclear cells without detectable HCV RNA in the serum. Here, we aimed to review the epidemiology, diagnostic methods, clinical implications and potential management recommendations currently described in the literature, as well as the future directions for investigation of this entity. PubMed and Cochrane databases were searched with combination of the following keywords: "occult", "hepatitis C virus", and "occult HCV infection". There are data to support OCI as a potential culprit in cryptogenic liver disease. There are also consistent data demonstrating the existence of OCI in specific populations, such as dialysis, human immunodeficiency virus-infected and hepatitis B virus-infected patients, and also in the general population. While the gold standard for diagnosis is liver biopsy, examination of peripheral blood mononuclear cells may be a reliable, safer alternative method of diagnosis. Occult HCV infection is likely associated with liver fibrosis and progression of liver disease. Additional studies are required to determine the infectivity of OCI patients, as well as clarify the natural course and specific clinical implications of OCI. Lastly, studies are needed to determine whether treatment of OCI leads to decreased morbidity and/or mortality.

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.

Global elimination of hepatitis C virus infection: Progresses and the remaining challenges

Today, with the introduction of interferon-free direct-acting antivirals and outstanding progresses in the prevention, diagnosis and treatment of hepatitis C virus (HCV) infection, the elimination of HCV infection seems more achievable. A further challenge is continued transmission of HCV infection in high-risk population specially injecting drug users (IDUs) as the major reservoir of HCV infection. Considering the fact that most of these infections remain undiagnosed, unidentified HCV-infected IDUs are potential sources for the rapid spread of HCV in the community. The continuous increase in the number of IDUs along with the rising prevalence of HCV infection among young IDUs is harbinger of a forthcoming public health dilemma, presenting a serious challenge to control transmission of HCV infection. Even the changes in HCV genotype distribution attributed to injecting drug use confirm this issue. These circumstances create a strong demand for timely diagnosis and proper treatment of HCV-infected patients through risk-based screening to mitigate the risk of HCV transmission in the IDUs community and, consequently, in the society. Meanwhile, raising general awareness of HCV infection, diagnosis and treatment through public education should be the core activity of any harm reduction intervention, as the root cause of failure in control of HCV infection has been lack of awareness among young drug takers. In addition, effective prevention, comprehensive screening programs with a specific focus on high-risk population, accessibility to the new anti-HCV treatment regimens and public education should be considered as the top priorities of any health policy decision to eliminate HCV infection.

Genotype and genetic variation of HCV infections with low-risk factors in Putian coastal regions, China

Hepatitis C virus (HCV) infection is one of the leading causes of death and morbidity associated with liver disease. Risk factors identified for the transmission of HCV include contaminated blood products, intravenous drug use, body piercing, an infected mother at birth, sexual activity, and dental therapy, among others. However, the exact diversity of the HCV genotype and genetic variation among patients with low-risk factors is still unknown. In this study, we briefly described and analysed the genotype distribution and genetic variation of HCV infections with low-risk factors using molecular biology techniques. The results suggested that genotype 1b was predominant, followed by genotypes 2a and 1a. Genetic variations in the 5' UTR sequences of HCV were identified, including point mutations, deletions, and insertions. The frequency of genetic variations in 1b was higher than in 2a. This study provides considerable value for the prevention and treatment of liver disease caused by HCV among patients with low-risk factors and for the development of HCV diagnostic reagents and vaccines.

Prevalence of Occult Hepatitis C Virus Infection among Blood Donors in Jiangsu, China

OBJECTIVE

In 2010, only 1 donor blood sample was found to be anti-hepatitis C virus (HCV) negative and HCV RNA positive, as detected by nucleic acid testing. In occult HCV infection (OCI), HCV RNA is found in peripheral blood mononuclear cells (PBMCs). We investigated the prevalence of OCI among blood donors.

METHODS

We collected 513 samples from 334 eligible and 179 deferred donors, including 55 anti-HCV-positive, 113 alanine aminotransferase (ALT)-elevated, and 11 hepatitis B virus surface antigen (HBsAg)-positive blood donors. PBMCs were isolated, the 5'-untranslated region of HCV RNA was amplified by reverse transcription nested PCR, and the genotype of the core region was determined.

RESULTS

No HCV RNA was detected among the eligible samples. Among the deferred donors, 15 (27.2%) had detectable HCV RNA in 55 anti-HCV PBMC specimens. HCV RNA was detected in 1 (9.1%) HBsAg-positive and 9 (8%) ALT-elevated samples. The prevalence of OCI in the blood donors was 2.2% (10/458). HCV genotypes were determined in 10 subjects, indicating that 2 (20.0%) were subtype 2a, 7 (70.0%) were 1b, and 1 (10%) was 6a.

CONCLUSIONS

This study showed that OCI does exist among Chinese blood donors. However, to determine the epidemiology and outcome of this HCV infection, further follow-up with more participants and patients receiving blood components with OCI is needed.

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.

Interleukin-28B polymorphisms and interferon gamma inducible protein-10 serum levels in seronegative occult hepatitis C virus infection

Polymorphisms upstream interleukin (IL)-28B gene and serum levels of interferon gamma inducible protein-10 (IP-10) are associated with spontaneous and treatment-induced hepatitis C virus (HCV) clearance. Patients with seronegative occult HCV infection are anti-HCV and serum HCV-RNA negative but have viral RNA in liver and abnormal values of liver enzymes. We examined if the rs12979860 polymorphism of IL-28B and serum IP-10 levels differ between chronic and seronegative occult CV infection. IL-28B polymorphism was determined with allele specific TaqMan probes in total DNA isolated from peripheral blood mononuclear cells and IP-10 by an enzyme-linked immunosorbent assay in serum from 99 patients with seronegative occult HCV infection and 130 untreated patients with chronic hepatitis C. IL-28B genotypes were also determined in 54 healthy volunteers. Prevalence of the IL-28B CC genotype was significantly higher in seronegative occult HCV infection (52/99; 52.5%) than in chronic hepatitis C (32/130; 24.6%, P < 0.0001) or healthy controls (19/54: 32.5%, P = 0.039). Among patients with seronegative occult HCV infection, HCV-RNA load in liver was significantly lower in those with the IL-28B CC genotype than in those with CT + TT genotypes (2.8 × 10(5)  ± 5.8 × 10(4) vs. 4.1 × 10(5)  ± 5.9 × 10(4)  copies/μg of total RNA respectively; P = 0.023). Mean serum IP-10 levels were significantly lower in patients with seronegative occult HCV infection than in patients with chronic hepatitis C (160.8 ± 17.9 vs. 288.7 ± 13.3 pg/ml respectively; P < 0.0001). These findings suggest that the host immune response plays an important role in seronegative occult HCV infection in comparison with chronic hepatitis C.

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.

Epidemiology of hepatitis C virus in Iran

In Iran, the prevalence of hepatitis C virus (HCV) infection is relatively low according to the population-based epidemiological studies. However, the epidemiology of HCV is changing and the rate of HCV infection is increasing due to the growth in the number of injecting drug users in the society. In addition, a shift has occurred in the distribution pattern of HCV genotypes among HCV-infected patients in Iran. Genotype 1a is the most prevalent genotype in Iran, but in recent years, an increase in the frequency of 3a and a decrease in 1a and 1b have been reported. These variations in the epidemiology of HCV reflect differences in the routes of transmission, status of public health, lifestyles, and risk factors in different groups and geographic regions of Iran. Health policy makers should consider these differences to establish better strategies for control and prevention of HCV infection. Therefore, this review was conducted to present a clear view regarding the current epidemiology of HCV infection in Iran.

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.

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.

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

BACKGROUND & AIMS

Detection of hepatitis C virus (HCV) RNA in peripheral blood mononuclear cells (PBMC) and/or hepatocytes in absence of HCV RNA in serum, designated as 'occult HCV infection', has been a matter of controversy in recent years. We investigated for the first time the prevalence of occult HCV infection in large cohorts of chronic hemodialysis (CHD) and kidney transplant (KTx) patients.

METHODS

We enrolled 417 CHD patients, 417 KTx recipients and 2 control groups - 25 anti-HCV (antibody against HCV)-positive and HCV RNA-positive patients with chronic hepatitis C, and 40 anti-HCV-, HCV RNA-, and HBsAg-negative healthy subjects. HCV RNA was tested in serum and PBMC using a sensitive commercial assay.

RESULTS

In CHD patients, the prevalence of anti-HCV was 3.6% (15/417) and of positive serum HCV RNA 2.4% (10/417). HCV RNA was detected in PBMC in 1/407 (0.25%) HCV serum RNA-negative patients ("occult HCV infection"). In KTx recipients, prevalence of anti-HCV was 4.8% (20/417) and of positive serum HCV RNA 4.6% (19/417). Occult HCV infection was found in 2/398 (0.5%) serum HCV RNA-negative patients. On a mean longitudinal follow-up of 30months of the 3 patients with occult HCV infection, there was no clinical or virological evidence of HCV infection.

CONCLUSIONS

The prevalence of occult HCV infection was very low in our CHD and KTx patients, and it did not appear to be clinically relevant. Further studies in geographic populations with high HCV endemicity are required to clarify the significance of occult HCV infection in these patient groups.

High prevalence of occult hepatitis C virus infection in patients with primary and secondary glomerular nephropathies

The association of hepatitis C virus (HCV) infection and glomerulonephritis is well known. However, the relationship between immune-mediated glomerulonephritis and occult HCV, characterized by the presence of HCV-RNA in liver or in peripheral blood mononuclear cells in the absence of serological markers, is unknown. We tested this in 113 anti-HCV-negative patients; 87 with immune-mediated glomerulonephritis and 26 controls with hereditary glomerular nephropathies. All patients were serum HCV-RNA negative by conventional real-time PCR. Significantly, occult HCV-RNA (detectable viral RNA in peripheral blood mononuclear cells or in serum after ultracentrifugation) was found in 34 of 87 patients with immune-mediated glomerulonephritis versus 1 of 26 control patients. The serum creatinine levels were significantly higher in patients with immune-mediated glomerulonephritis with than in those without occult HCV (1.5 versus 1.1 mg/dl, respectively). A multivariate analysis adjusted for gender showed a significantly increased risk of occult HCV in patients with immune-mediated glomerulonephritis versus the controls (odds ratio of 13.29). Progression to end-stage renal disease tended to be faster in patients with immune-mediated glomerulonephritis and occult HCV than in the negative cases. Thus, occult HCV is strongly associated with immune-mediated glomerulonephritis and may have a role in the progression of the disease.

Occult hepatitis C virus infection in candidates for liver transplant with cryptogenic cirrhosis

BACKGROUND

Occult hepatitis C virus (HCV) infection is a new entity described by the presence of HCV-RNA in liver biopsy and/or peripheral blood mononuclear cell (PBMC) specimens, and undetectable levels or absence of HCV-RNA and in the absence or presence of anti HCV antibodies in plasma by current laboratory methods.

OBJECTIVES

To evaluate the detection of HCV-RNA in PBMC specimens of the liver transplant candidates with cryptogenic cirrhosis by reverse transcriptase-nested polymerase chain reaction (RT-nested PCR).

PATIENTS AND METHODS

From November 2007 to March 2013, 45 patients from Liver Transplant Center of Imam Khomeini Hospital, Tehran, were enrolled in this cross sectional study. PBMC specimens were separated from the peripheral blood sample. After extraction of RNA from plasma and PBMC specimens, HCV-RNA status was tested by RT-nested PCR. The 5'-untranslated region (5'-UTR) genotyping of HCV-RNA amplified from PBMC specimens was performed by a standard methodology with the INNO-LiPA(TM) HCV II kit. The PCR products of 5'-UTR were sequenced after cloning into the pJET1.2 / blunt cloning vector.

RESULTS

Of 45 patients, 4 (8.9% [95% CI: 4.4-15.6]) had detectable genomic HCV-RNA in their PBMC specimens. HCV genotypes were determined in the PBMCs of these subjects showed that 2 (50.0%) subjects with occult HCV infection had HCV subtype 3a, and 2 (50.0%) had HCV subtype 1b.

CONCLUSIONS

This study found that 8.9 % of the Iranian candidates for liver transplant with cryptogenic cirrhosis had occult HCV infection. Therefore, designing prospective studies focusing on the diagnosis of occult HCV infection in these subjects prior to liver transplantation could be valuable.

Durability of SVR in chronic hepatitis C patients treated with peginterferon-α2a/ribavirin in combination with a direct-acting anti-viral

BACKGROUND

The introduction of direct-acting anti-virals has increased sustained virological response (SVR) rates in chronic hepatitis C genotype 1 infection. At present, data on long-term durability of viral eradication after successful triple therapy are lacking.

AIM

To evaluate the long-term durability of viral eradication in patients treated with triple therapy, including direct-acting anti-virals.

METHODS

Patients who participated in randomised, controlled trials or an extended access programme of treatment with peginterferon-α2a/ribavirin in combination with a direct-acting anti-viral (telaprevir, danoprevir, faldaprevir, simeprevir, mericitabine, balapiravir) were followed after achieving SVR. The median follow-up after the patients was 21 (range: 7-64) months.

RESULTS

One hundred and three patients with chronic hepatitis C genotype 1 infection [f/m: 34/69; GT-1b: 67 GT-1a: 34, GT-4: 2; mean age: 47.6 years (45.5-49.7; 95% CI)] achieving a SVR triple therapy were followed. Two cases of late relapses (2/103, 1.9%; 95% CI: 0.24-6.8) were observed. One patient was cirrhotic, both carried the genotype 1b and completed the prescribed treatment. The relapses occurred 8 and 12 months after cessation of anti-viral treatment. Cloning sequencing revealed identical sequence in both patients. Resistance analysis revealed no presence of viral resistance.

CONCLUSION

Like the SVR after peginterferon-α2/ribavirin combination treatment, HCV eradication after triple therapy remains durable after long-term follow-up.

High prevalence of occult hepatitis C virus infection in patients with chronic hepatitis B virus infection

Hepatitis C virus (HCV) infection in the absence of detectable antibodies against HCV and of viral RNA in serum is called occult HCV infection. Its prevalence and clinical significance in chronic hepatitis B virus (HBV) infection is unknown. HCV RNA was tested for in the liver samples of 52 patients with chronic HBV infection and 21 (40 %) of them were positive for viral RNA (occult HCV infection). Liver fibrosis was found more frequently and the fibrosis score was significantly higher in patients with occult HCV than in negative ones, suggesting that occult HCV infection may have an impact on the clinical course of HBV infection.