Increased vertical transmission of human immunodeficiency virus from hepatitis C virus-coinfected mothers. Women and Infants Transmission Study

Understanding Viral and Immune Interplay During Vertical Transmission of HIV: Implications for Cure

Despite the significant progress that has been made to eliminate vertical HIV infection, more than 150,000 children were infected with HIV in 2019, emphasizing the continued need for sustainable HIV treatment strategies and ideally a cure for children. Mother-to-child-transmission (MTCT) remains the most important route of pediatric HIV acquisition and, in absence of prevention measures, transmission rates range from 15% to 45% via three distinct routes: in utero, intrapartum, and in the postnatal period through breastfeeding. The exact mechanisms and biological basis of these different routes of transmission are not yet fully understood. Some infants escape infection despite significant virus exposure, while others do not, suggesting possible maternal or fetal immune protective factors including the presence of HIV-specific antibodies. Here we summarize the unique aspects of HIV MTCT including the immunopathogenesis of the different routes of transmission, and how transmission in the antenatal or postnatal periods may affect early life immune responses and HIV persistence. A more refined understanding of the complex interaction between viral, maternal, and fetal/infant factors may enhance the pursuit of strategies to achieve an HIV cure for pediatric populations.

Quasispecies Diversity Is a Major Risk Factor for Vertical Hepatitis C Virus Transmission

BACKGROUND

Vertical transmission is the major cause of pediatric hepatitis C virus (HCV) infection. The objective of this study was to better understand HCV pathogenesis in pregnant women and provide insights into risk factors and mechanisms involved in vertical transmission.

METHODS

Evolutionary dynamics of HCV variant spectra and HCV-specific neutralizing antibody responses were examined using high-throughput sequencing and pseudoparticle-based assays in pregnant women monoinfected with HCV (n = 17) or coinfected with HCV and human immunodeficiency virus (HIV)-1 (n = 15).

RESULTS

Overall, statistically significant associations were found between HCV quasispecies diversity, selective pressure exerted on the HCV E2 envelope protein, and neutralizing activity of maternal immunoglobulins. Women with low quasispecies diversity displayed significantly higher mean aspartate aminotransferase and alanine aminotransferase levels throughout pregnancy, but this difference was restricted to monoinfected participants. Low quasispecies diversity and inefficient neutralizing activity were also significantly associated with vertical transmission, but only in the monoinfected group.

CONCLUSIONS

These results indicate that maternal neutralizing antibody responses play a role in the prevention of vertical HCV transmission, but not in presence of HIV-1 coinfection, and suggest that the mechanism of vertical transmission may be different between monoinfected and coinfected women. These findings could inform management strategies for the prevention of vertical HCV transmission.

No. 96-The Reproductive Care of Women Living With Hepatitis C Infection

OBJECTIVE

hepatitis C virus (HCV) is an increasingly important public health problem worldwide. Health care workers providing care to women of childbearing age are uniquely placed in their practices to identify a significant proportion of at-risk patients and to provide appropriate screening and counselling. The primary objective of this guideline is to provide accurate, current information to those offering reproductive care to women living with HCV. This document is also intended to raise awareness of HCV in both the medical and general populations.

OPTIONS

the areas of clinical practice considered in formulating this guideline are disease prevention, targeted screening of individuals at risk of contracting HCV, management of identified patients in the context of reproductive care, and the appropriate referral of patients to those with particular expertise.

OUTCOMES

implementation of these guidelines should facilitate identification of infected individuals. It should also result in improved physical and mental well-being for patients and their families and reduction in transmission rates.

EVIDENCE

the literature between 1966 and 2000, including non- English language publications, was extensively searched utilizing Medline. A multidisciplinary group consisting of experts within the fields of obstetrics and gynaecology, infectious diseases, hepatology, and public health convened in Montreal in February 2000. The working group also included a patient and a representative from the Hepatitis C Society of Canada. The level of evidence for the recommendations has been determined using the criteria described by the Canadian Task Force on Periodic Health Examination.

BENEFITS, HARMS AND COSTS

the public health benefits of increased identification of at-risk individuals, diagnosis, treatment, implementation of risk reduction behaviours, and reduced transmission rates, both on an individual and at the community level, are significant. However, it must be remembered that the diagnosis of a chronic disease may have far reaching effects for the individual patient and her family.

RECOMMENDATIONS

VALIDATION: references were collected through Medline searches and comparison made to existing current guidelines for assessment of consistency. External reviewers expert in their field were also consulted.

Immunogenetic studies of the hepatitis C virus infection in an era of pan-genotype antiviral therapies - Effective treatment is coming

What are the factors that influence human hepatitis C virus (HCV) infection, hepatitis status establishment, and disease progression? Firstly, one has to consider the genetic background of the host and HCV genotypes. The immunogenetic host profile will reflect how each infected individual deals with infection. Secondly, there are environmental factors that drive susceptibility or resistance to certain viral strains. These will dictate (I) the susceptibility to infection; (II) whether or not an infected person will promote viral clearance; (III) the immune response and the response profile to therapy; and (IV) whether and how long it would take to the development of HCV-associated diseases, as well as their severity. Looking at this scenario, this review addresses clinical aspects of HCV infection, following by an update of molecular and cellular features of the immune response against the virus. The evasion mechanisms used by HCV are presented, considering the potential role of exosomes in infection. Genetic factors influencing HCV infection and pathogenesis are the main topics of the article. Shortly, HLAs, MBLs, TLRs, ILs, and IFNLs genes have relevant roles in the susceptibility to HCV infection. In addition, ILs, IFNLs, as well as TLRs genes are important modulators of HCV-associated diseases. The viral aspects that influence HCV infection are presented, followed by a discussion about evolutionary aspects of host and HCV interaction. HCV and HIV infections are close related. Thus, we also present a discussion about HIV/HCV co-infection, focusing on cellular and molecular aspects of this interaction. Pharmacogenetics and treatment of HCV infection are the last topics of this review. The understanding of how the host genetics interacts with viral and environmental factors is crucial for the development of new strategies to prevent HCV infection, even in an era of potential development of pan-genotypic antivirals.

Hepatitis C in Children Co-infected With Human Immunodeficiency Virus

OBJECTIVES

The objective of this systematic review was to summarize evidence regarding hepatitis C in hepatitis C virus/human immunodeficiency virus (HCV/HIV)-co-infected children focusing on mother-to-child transmission, clinical and laboratory features, outcome, and therapies.

METHODS

A literature search was performed using multiple keywords and standardized terminology in MEDLINE, EMBASE, and Cochrane databases dating back to their inception up to April 1, 2015, using the following terms hepatitis C virus, HIV, and child.

RESULTS

Fifty-five of 367 publications were selected for inclusion. In co-infected children, HIV impacted all the different aspects of HCV infection. Maternal HIV infection increased the risk of vertical transmission of hepatitis C. Children with HCV/HIV co-infection presented a lower rate of spontaneous clearance of HCV, were more commonly HCV viraemic, and had higher values of alanine aminotransferase when compared with HCV-monoinfected children. No relevant difference was reported between monoinfection and co-infection with regard to clinical findings. Although the data on the outcome of hepatitis C in the context of co-infection were limited, they were highly suggestive of a more severe outcome in terms of fibrosis in co-infected children. No pediatric data were available on the role of antiretroviral therapy as a cofactor of liver injury in HCV/HIV co-infection. The efficacy of pegylated interferon-α and ribavirin in children with HCV/HIV co-infection was lower than in monoinfected children.

CONCLUSIONS

The effect of HIV co-infection on HCV-related disease was clear with most studies indicating that HIV accelerates HCV progression and reduces the efficacy of the available anti-HCV therapies.

HCV and HIV co-infection: mechanisms and management

HCV and HIV co-infection is associated with accelerated hepatic fibrosis progression and higher rates of liver decompensation and death compared to HCV monoinfection, and liver disease is a leading cause of non-AIDS-related mortality among HIV-infected patients. New insights have revealed multiple mechanisms by which HCV and HIV lead to accelerated disease progression, specifically that HIV infection increases HCV replication, augments HCV-induced hepatic inflammation, increases hepatocyte apoptosis, increases microbial translocation from the gut and leads to an impairment of HCV-specific immune responses. Treatment of HIV with antiretroviral therapy and treatment of HCV have independently been shown to delay the progression of fibrosis and reduce complications from end-stage liver disease among co-infected patients. However, rates of sustained virologic response with PEG-IFN and ribavirin have been significantly inferior among co-infected patients compared with HCV-monoinfected patients, and treatment uptake has remained low given the limited efficacy and tolerability of current HCV regimens. With multiple direct-acting antiviral agents in development to treat HCV, a unique opportunity exists to redefine the treatment paradigm for co-infected patients, which incorporates data on fibrosis stage as well as potential drug interactions with antiretroviral therapy.

The role of co-infections in mother-to-child transmission of HIV

In HIV-infected women, co-infections that target the placenta, fetal membranes, genital tract, and breast tissue, as well as systemic maternal and infant infections, have been shown to increase the risk for mother-to-child transmission of HIV (MTCT). Active co-infection stimulates the release of cytokines and inflammatory agents that enhance HIV replication locally or systemically and increase tissue permeability, which weakens natural defenses to MTCT. Many maternal or infant co-infections can affect MTCT of HIV, and particular ones, such as genital tract infection with herpes simplex virus, or systemic infections such as hepatitis B, can have substantial epidemiologic impact on MTCT. Screening and treatment for co-infections that can make infants susceptible to MTCT in utero, peripartum, or postpartum can help reduce the incidence of HIV infection among infants and improve the health of mothers and infants worldwide.

Mother-to-child transmission of human immunodeficiency virus in aten years period

Objectives

to evaluate mother-to-child transmission (MTCT) rates and related factors in HIV-infected pregnant women from a tertiary hospital between 2000 and 2009.

Subjects and method

cohort of 452 HIV-infected pregnant women and their newborns. Data was collected from recorded files and undiagnosed children were enrolled for investigation. Statistical analysis: qui-square test, Fisher exact test, Student t test, Mann-Whitney test, ANOVA, risk ratio and confidence intervals.

Results

MTCT occurred in 3.74%. The study population displayed a mean age of 27 years; 86.5% were found to have acquired HIV through sexual contact; 55% were aware of the diagnosis prior to the pregnancy; 62% were not using HAART. Mean CD4 cell-count was 474 cells/ml and 70.3% had undetectable viral loads in the third trimester. HAART included nevirapine in 35% of cases and protease inhibitors in 55%; Zidovudine monotherapy was used in 7.3%. Mean gestational age at delivery was 37.2 weeks and in 92% by caesarian section; 97.2% received intravenous zidovudine. Use of AZT to newborn occurred in 100% of them. Factors identified as associated to MTCT were: low CD4 cell counts, elevated viral loads, maternal AIDS, shorter periods receiving HAART, other conditions (anemia, IUGR (intra uterine growth restriction), oligohydramnium), coinfecctions (CMV and toxoplasmosis) and the occurrence of labor. Use of HAART for longer periods, caesarian and oral zidovudine for the newborns were associated with a decreased risk. Poor adhesion to treatment was present in 13 of the 15 cases of transmission; in 7, coinfecctions were diagnosed (CMV and toxoplasmosis).

Conclusion

Use of HAART and caesarian delivery are protective factors for mother-to-child transmission of HIV. Maternal coinfecctions and other conditions were risk factors for MTCT.

Host factors that influence mother-to-child transmission of HIV-1: genetics, coinfections, behavior and nutrition

Mother-to-child transmission (MTCT) is the most important mode of HIV-1 acquisition among infants and children and it can occur in utero, intrapartum and postnatally through breastfeeding. Great progress has been made in preventing MTCT through use of antiretroviral regimens during gestation, labor/delivery and breastfeeding. The mechanisms of MTCT, however, are multifactorial and remain incompletely understood. This review focuses on select host factors affecting MTCT, in particular genetic factors, coexisting infections, behavioral factors and nutrition. Whereas much emphasis has been placed on decreasing maternal HIV-1 viral load, an important determinant of MTCT, through use of antiretroviral agents, complementary focus on overall maternal health is often neglected. By addressing coinfections in mothers and infants, improving the mother's nutritional status and modifying risky behaviors and practices, not only is maternal and child health improved, but a direct benefit in reducing MTCT can be derived. The study of genetic variations in susceptibility to HIV-1 infection is rapidly evolving, and the future is likely to bring revolutionary changes in HIV-1 prevention by enhancing natural resistance to infection and by individually tailoring pharmacologic regimens.

Human immunodeficiency virus-hepatitis C virus co-infection in pregnant women and perinatal transmission to infants in Thailand

OBJECTIVES

The objectives of this study were to assess the prevalence and factors associated with hepatitis C virus (HCV) infection in human immunodeficiency virus (HIV)-infected and -uninfected Thai pregnant women and the rate of HCV transmission to their infants.

PATIENTS AND METHODS

Study subjects included 1435 HIV-infected pregnant women and their infants, enrolled in a perinatal HIV prevention trial, and a control group of 448 HIV-uninfected pregnant women. Women were screened for HCV antibodies with an enzyme immunoassay. Positive results were confirmed by recombinant immunoblot and HCV RNA quantification. Infants were tested for HCV antibodies at 18 months or for HCV RNA at between 6 weeks and 6 months.

RESULTS

Of the HIV-infected women, 2.9% were HCV-infected compared to 0.5% of HIV-uninfected women (p=0.001). Only history of intravenous drug use was associated with HCV infection in HIV-infected women. Ten percent of infants born to co-infected mothers acquired HCV. The risk of transmission was associated with a high maternal HCV RNA (p=0.012), but not with HIV-1 load or CD4 count.

CONCLUSIONS

Acquisition of HCV through intravenous drug use partially explains the higher rate of HCV infection in HIV-infected Thai women than in HIV-uninfected controls. Perinatal transmission occurred in 10% of infants of HIV-HCV-co-infected mothers and was associated with high maternal HCV RNA.

Maternal neutralizing antibody and transmission of hepatitis C virus to infants

To determine whether lower levels of hepatitis C virus (HCV)-specific neutralizing antibodies (nAb) are associated with an increased risk of mother-to-child transmission (MTCT) of HCV, HCV nAb titers were assessed in 63 mothers coinfected with HCV and human immunodeficiency virus (HIV) type 1. Of the mothers, 16 transmitted HCV to their infant, but no difference was detected between the ability of maternal plasma from transmitters and nontransmitters to neutralize heterologous HCV pseudoparticles (median nAb titer, 1:125 vs. 1:100; P = .23). In the setting of HIV/HCV coinfection, we found no evidence that HCV nAbs are associated with the prevention of MTCT of HCV.

The challenge of hepatitis C in the HIV-infected person

Hepatitis C virus (HCV) coinfection occurs in an estimated one quarter of HIV-infected persons in Europe, Australia, and the United States. As use of highly active antiretroviral drugs has markedly reduced opportunistic infections, HCV-related liver disease has emerged as a leading cause of death. HIV infection adversely affects both the natural history and the treatment of hepatitis C. Because there are no experimental models of coinfection and because the pathogenesis of each infection is incompletely understood, how HIV infection alters hepatitis C is not clear. This review considers the epidemiology, natural history, treatment, and pathogenesis of hepatitis C in HIV-infected persons.

Parasite co-infection and interaction as drivers of host heterogeneity

We examined the hypothesis that the interaction between concomitant infecting parasites modifies host susceptibility, parasite intensity and the pattern of parasite distribution within the host population. We used a 26 year time series of three common parasites in a natural population of rabbits: two gastrointestinal nematodes (Trichostrongylus retortaeformis and Graphidium strigosum) and the immunosuppressive myxoma virus. The frequency distribution of nematodes in the host population and the relationship between host age and nematode intensity were explored in rabbits with either single or dual nematode infections and rabbits infected with the nematodes and myxoma virus. The aggregation of T. retortaeformis and G. strigosum among the rabbits varied with the nature of the co-infection both in male and female hosts. The two nematodes exhibited different age-intensity profiles: G. strigosum intensity increased exponentially with host age while T. retortaeformis intensity exhibited a convex shape. The presence of a secondary infection did not change the age-intensity profile for G. strigosum but for T. retortaeformis co-infection (either both nematodes or myxoma-nematodes) resulted in significantly greater intensities in adult hosts. Results suggest that multi-species infections contributed to aggregation of parasites in the host population and to seasonal variation in intensity, but also enhanced differences in parasitism between sexes. This effect was apparent for T. retortaeformis, which appears to elicit a strong acquired immune response but not for G. strigosum which does not produce any evident immune reaction. We concluded that concomitant infections mediated by host immunity are important in modifying host susceptibility and influencing heterogeneity amongst individual hosts.

Mother-to-infant transmission of multiple blood-borne viral infections from multi-infected mothers

Infants born from mothers with multiple blood-borne viral infections are at risk of multiple transmissions. Whether the risk of transmission of multiple infections increases with the number of viruses infecting the mother is still unknown. The aim of this study was to describe the risk of mother-to-infant transmission of multiple infections from multi-infected mothers. Sixty-four pregnant women infected by at least two viruses among human immunodeficiency virus-type 1 (HIV-1), hepatitis C virus, TT virus, and GB virus type C, together with their 64 infants, were studied. Maternal blood samples were collected in the third trimester of pregnancy and all infants were prospectively followed for evaluation of transmission within 3 months after birth and two times in the subsequent 24 months. Transmission of single and of dual infection from mothers infected by two viruses was, respectively, 10/40 (25%) and 5/40 (12.5%) and from mothers infected by three viruses 9/20 (45%) and 2/20 (10%). One (25%) infant infected by one virus was born from the four mothers infected by four viruses. Transmission of single or dual infection was not significantly associated with the number of viruses infecting the mother (P = 0.9) in the linear regression analysis. Present study suggests the absence of a synergistic effect from viral interactions toward mother-to-infant transmission of multiple infections and supports the hypothesis that transmission from multi-infected mothers is the result of the specific interaction between each virus and the host. These observations may be of clinical relevance in perinatal counseling.

Transcytosis of Human immunodeficiency virus 1 across the placenta is enhanced by treatment with tumour necrosis factor alpha

The human placenta is relatively resistant to Human immunodeficiency virus 1 (HIV-1), but obstetric complications associated with inflammatory processes, including chorioamnionitis and spontaneous preterm delivery, are associated with increased rates of vertical transmission. It was hypothesized that the pro-inflammatory mediator tumour necrosis factor alpha (TNF-alpha), which promotes HIV-1 transmission across endothelial membranes, increases HIV-1 transmission across the placenta. Flow cytometry and immunostaining studies were performed, which demonstrated that the HIV-1 receptors CD4, CCR5 and CXCR4 were not expressed by villous trophoblast cells. Consequently, primary villous trophoblast cells were not infected with cell-free HIV-1 isolates, as measured by in situ PCR and quantitative PCR, but villous trophoblast cells were infected by HIV-1-infected peripheral blood mononuclear cells (PBMC). HIV-1 from infected PBMC was rapidly transported across confluent transformed trophoblast cell monolayers by transcytosis, and TNF-alpha significantly upregulated transcytosis of HIV-1 across the trophoblast layer without disrupting cell viability or confluency. Inhibitors of TNF-alpha (antibodies against TNF-alpha and TNF-alpha receptors) and an anti-inflammatory drug (tenidap) significantly reduced transcytosis rates. It was concluded that the villous trophoblast is resistant to infection by cell-free HIV-1 but susceptible to transcytosis of HIV-1 from infected PBMC, and inflammatory mediators such as TNF-alpha may play a critical role in promoting maternal-fetal transmission of HIV-1.

Management of Hepatitis C Infection in the HIV-Infected Patient

Morbidity and mortality associated with HIV infection have rapidly decreased with the introduction of highly active antiretroviral therapy. Of recent concern is the increase of unusual opportunistic infections, particularly hepatitis C virus in this population. Because of the shared route of transmission, a significant number of HIV-infected patients are also coinfected with hepatitis C virus. HIV infection has been demonstrated to increase the rate of hepatitis C virus disease progression. New data on the use of pegylated interferon plus ribavirin indicate that while cure of hepatitis C virus in the coinfected patient is a clinical challenge, it is possible. Aggressive management of anemia, drug-induced depression, and drug interactions increase the opportunity for clinical response and positive patient outcomes.

Vertically acquired paediatric coinfection with HIV and hepatitis C virus

Both HIV and hepatitis C virus (HCV) can be transmitted from mother to child during pregnancy and delivery. Vertical transmission of HIV and HCV separately is most likely from HIV/HCV-coinfected mothers; however, transmission of both infections is less frequent. The effect of HCV coinfection on HIV-related disease remains unclear; whereas most studies indicate no effect, recent results suggest HCV in adults accelerates HIV progression. Little is known about how HIV coinfection affects HCV progression in children and the information available is based on small numbers of patients. Paediatric HIV treatment is extremely successful and it is vital to determine if HCV coinfection alters the effectiveness of this treatment. The hepatotoxicity of many HIV therapies and the possible negative impact of HCV on this treatment, alongside the interactions and contraindications of many HIV and HCV therapies, further limits the choice of paediatric treatments for coinfected children. Future research must therefore focus on vertically acquired HIV/HCV coinfection to inform treatment trials addressing coinfection management.

Presence of hepatitis C virus (HCV) RNA in the genital tracts of HCV/HIV-1-coinfected women

BACKGROUND

Hepatitis C virus (HCV)-infected women--in particular, those coinfected with human immunodeficiency virus type 1 (HIV-1)--can transmit infection to their children and sex partners.

METHODS

The present study was conducted to analyze the presence of HCV RNA in cervicovaginal lavage (CVL) fluid from 71 women (58 HCV/HIV-1-coinfected women and 13 HCV-infected, HIV-1-uninfected women) enrolled in the Women's Interagency HIV Study.

RESULTS

HCV RNA was detected (by a commercial polymerase chain reaction assay) in CVL fluid from 18 (29%) of the HIV-1-infected women and from none of the HIV-1-uninfected women (P<.05). Multivariate analysis revealed that risk factors for the presence of HCV RNA in CVL fluid were HCV viremia (odds ratio [OR], 16.81; P=.02) and HIV-1 RNA in CVL fluid (OR, 19.87; P=.02). This observation suggests local interactions between HIV-1 and HCV in the genital tract compartment. There was no correlation between HCV RNA in CVL fluid and CD4, CD8, or CD3 cell counts, HIV-1 RNA viremia, the number of leukocytes in CVL fluid, or HIV-1 therapy. Furthermore, in 3 of 5 analyzed patients who had a detectable CVL HCV RNA load, we found viral variants differing in the 5' untranslated region that were present neither in plasma nor in peripheral-blood mononuclear cells.

CONCLUSIONS

Our observations point to the importance of the genital tract compartment, in which local HCV replication could be facilitated by local HIV-1 replication.

A Study to Investigate the Impact of the Initiation of Highly Active Antiretroviral Therapy on the Hepatitis C Virus Viral Load in HIV/HCV-Coinfected Patients

Changes in the hepatitis C virus (HCV) viral load (VL) were assessed in a retrospective study of 50 HIV/HCV-coinfected patients who initiated highly active antiretroviral therapy (HAART). Most patients responded to HAART [during the first 6 months, plasma HIV VL fell by a mean 1.39 log10, becoming undetectable (<400 copies/ml) in 22% and CD4+ T cells increased by a mean of 100 cells/μl], but surprisingly, 27 (54%) showed some rise and 25 (50%) showed a significant increase in the HCV VL. This figure was considered to be a minimum estimate. A majority of the patients showed an increase of less than 1 log10 that was associated with a rapid decrease in the HIV VL, whereas an increase in the HCV VL of greater than 1 log10, noted in eight patients, was associated with a baseline CD4+ cell count of less than 200 cells/μl. The increase in the HCV VL was not associated with hepatitis as determined by raised alanine transferase.

Hepatitis C-HIV coinfection: current and future therapy

Coinfection with hepatitis C in HIV-infected patients has been reported in 15-70% of patients depending on the mode of acquisition of both viruses. As recent advances in HIV-directed antiviral therapy have markedly delayed HIV progression and mortality, the incidence of complications arising from hepatitis C-associated liver disease in coinfected patients is increasing exponentially. The interaction of HIV and hepatitis C is complex. It is clear that HIV infection negatively affects the natural history of hepatitis C, while HIV-directed therapy may enhance immunologic response and exacerbate hepatocellular injury induced by hepatitis C via immune reconstitution. In this review, the pathobiology, inter-relation of hepatitis C and HIV infection in coinfected patients as well as present and future treatment in this unique patient population are discussed.

Treatment of the hepatitis C virus in patients coinfected with HIV

Hepatitis C virus (HCV) coinfection is common among individuals with HIV, and the progression of liver disease is accelerated in coinfected individuals compared with those with HCV alone. HCV coinfection also can decrease tolerability of highly active antiretroviral therapy. Additionally, the presence of HCV appears to increase morbidity and mortality in these individuals, and as such the management of both HCV and HIV in coinfected individuals requires careful consideration. Although coinfected patients should be considered for HCV therapy, the limited information to date indicates a lower rate of virologic response with current HCV therapies. Moreover, interactions between HCV and HIV antiviral medications may occur and potentially affect treatment efficacy. Thus, the decision to undertake HCV treatment must be individualized.

Influence of maternal human immunodeficiency virus (HIV) co-infection on vertical transmission of hepatitis C virus (HCV): a meta-analysis

BACKGROUND

Maternal co-infection with human immunodeficiency virus (HIV) has been implicated as a potentially important co-factor for enhanced vertical transmission of hepatitis C virus (HCV). In previous reports, however, methodological issues (notably small sample sizes) have limited accurate evaluation of the contribution of maternal co-infection with HIV on the risk of vertical transmission of HCV.

METHODS

A systematic review and subsequent meta-analysis of current published and unpublished reports was performed. Odds ratios (OR) and 95% CI for individual studies were calculated with maternal HIV serostatus as the exposure measure and HCV vertical transmission as the outcome measure. Overall summary estimates were then calculated using a random effects model that estimates a weighted average of OR from individual studies.

RESULTS

In total, 2382 infants from 10 studies were included in an analysis of HCV-infected mothers (defined by anti-HCV+ antibody assays) with and without concomitant HIV infection. The risk estimate (OR) of HCV vertical transmission was 2.82 (95% CI: 1.78-4.45; P = 0.00001) from anti-HCV+/HIV+ co-infected mothers compared with anti-HCV+/HIV- mothers. In a subanalysis of 1327 infants born to viraemic (HCV RNA+) mothers, the risk estimate of HCV vertical transmission was 1.97 (95% CI: 1.04-3.74; P = 0.04) from HCV viraemic/HIV+ co-infected mothers compared with HCV viraemic/HIV- mothers.

CONCLUSIONS

Results from this meta-analysis of observational studies suggest that the risk of HCV vertical transmission is higher in infants born to HIV co-infected mothers.

Hepatitis C virus infection in children coinfected with HIV: epidemiology and management

Mothers with hepatitis C virus (HCV) and HIV coinfection are the major source of HCV/HIV coinfection in infancy and childhood. There is no known intervention capable of interrupting HCV spread from mother to child, while the majority of infant HIV infections occurring in the developed world can be prevented by antiretroviral prophylaxis in the mother and child, elective caesarean section, and formula-feeding. In the era preceding treatment of HIV infection with highly active antiretroviral therapy, HCV coinfection was of little concern because the short-term survival of patients with HIV infection prevented the slowly developing consequences of chronic hepatitis C. As the life expectancy of patients with HIV infection increased with therapy, HCV has emerged as a significant pathogen. Several lines of evidence in adult patients suggest that liver disease may be more severe in patients coinfected with HIV and that progression of HIV disease may be accelerated by HCV coinfection. Whether coinfected children may share these clinical patterns remains a matter of speculation. Chronic hepatitis C in otherwise healthy children is usually a mild disease; liver damage may be sustained and fibrosis may increase over the years, suggesting slow progression of the disease. Interferon-alpha has been the only drug used in the past decade to treat hepatitis C in children and adolescents, with average response rates of 20%. Preliminary results of treatment with interferon-alpha and ribavirin suggest that the efficacy would be greater with combined therapy. These treatment protocols have not yet been applied to children coinfected with HIV, but the increasing number of long-term survivors will probably prompt further investigation in the near future. At present, treating HIV disease and monitoring HCV infection and hepatotoxicity induced by antiretroviral drugs seem to be the more reasonable approach to HCV/HIV coinfection in childhood.

Hepatitis C in the HIV-infected patient

Hepatitis C virus infection is common in people with HIV and represents an increasingly important public health problem. Thus, although there remains a considerable amount of uncertainty about whom to treat and the best way to treat, providers must use available information generated chiefly from patients without HIV to manage HCV infection in coinfected patients. Future efforts should include prospective studies that demonstrate the natural history and optimal management of HIV/HCV-coinfected patients, including the feasibility of liver transplantation.

Assisted reproductive technology for men and women infected with human immunodeficiency virus type 1

In 2001, the World Health Organization reported 4.3 million new human immunodeficiency virus (HIV) infections in adults globally, 41% of which were in women. During the year 2000, 27% of newly diagnosed HIV infections in the United States occurred in women. In developed countries, the perception of HIV infection has changed from an acute, lethal infection to a chronic illness; the introduction of highly active antiretroviral therapy has decreased morbidity and mortality, and new drug therapies have dramatically decreased perinatal transmission. In view of these advances, some HIV-infected individuals are considering reproduction. Following the lead of organizations in other developed countries, the American College of Obstetricians and Gynecologists has recently endorsed the use of reproductive technology in HIV-infected patients. Which patients should be offered assisted reproduction and what the optimal methods are of decreasing heterosexual and perinatal HIV transmission must be determined.

Hepatitis C in the setting of HIV co-infection

Hepatitis C virus (HCV) co-infection is common among HIV-infected individuals and can lead to increased morbidity and mortality in this population. HIV adversely impacts the natural history of HCV disease with higher rates of liver disease progression but the effect of HCV on the natural history of HIV is disputed. Additionally, presence of HCV may decrease tolerability of highly active antiretroviral regimens for HIV treatment due to a potential increase in hepatotoxicity. Currently there is limited information available regarding HCV therapy in the setting of HIV co-infection but the HCV virologic response to interferon regimens appears to be similar to those individuals with HCV infection alone. However, additional information is required to assess the efficacy and safety of HCV therapy including possible interaction of HCV and HIV anti-viral medications in these co-infected individuals.

Vertical transmission of human immunodeficiency virus

Sensitive detection methods, such as DNA PCR and RNA PCR suggest that vertical transmission of human immunodeficiency virus (HIV) occurs at three major time periods; in utero, around the time of birth, and postpartum as a result of breastfeeding (Fig. 1). Detection of proviral DNA in infant's blood at birth suggests that transmission occurred prior to delivery. A working definition for time of infection is that HIV detection by DNA PCR in the first 48 h of life indicates in utero transmission, while peripartum transmission is considered if DNA PCR is negative the first 48 h, but then it is positive 7 or more days later [1]. Generally, in the breastfeeding population, breast milk transmission is thought to occur if virus is not detected by PCR at 3-5 months of life but is detected thereafter within the breastfeeding period [2]. Using these definitions and guidelines, studies has suggested that in developed countries the majority, or two thirds of vertical transmission occur peripartum, and one-third in utero [3-6]. The low rate of breastfeeding transmission is due to the practice of advising known HIV-positive mothers not to feed breast milk. However, since the implementation of antiretroviral treatment in prophylaxis of HIV-positive mothers, some studies have suggested that in utero infection accounts for a larger percentage of vertical transmissions [7]. In developing countries, although the majority of infections occurs also peripartum, a significant percentage, 10-17%, is thought to be due to breastfeeding [2, 8, 9].

Hepatitis C and human immunodeficiency virus coinfections

Hepatitis C virus (HCV) has become a major contributor to morbidity and mortality in patients with human immunodeficiency virus (HIV). It is estimated that 30% to 50% of patients with HIV are coinfected with HCV. Advances in antiretroviral therapy and improved life expectancy of HIV patients have resulted in an emergence of HCV-induced liver disease as a leading cause of significant morbidity and death in this population. Clinically, hepatitis C is a more severe disease in HIV-infected individuals, characterized by rapid progression toward end-stage liver disease. Highly active antiretroviral therapy is the mainstay of current acquired immunodeficiency syndrome management. One of the limiting side effects of combination therapy for HIV is hepatotoxicity, which is more common and often more serious in patients with underlying liver disease. Management of coinfected patients has no strict guidelines, but it is generally accepted that HIV infection needs to be treated before HCV. Hepatitis C in coinfected individuals is probably best treated using combination therapy (interferon alpha and ribavirin). It appears that combination therapy can safely be administered to this population and that previous concerns about ribavirin/zidovudine antagonism are unsubstantiated in clinical practice. Although initial results using only interferon alpha showed poor results in HIV coinfected patients, combination therapy seems to be as effective as in the general population. All HIV-HCV coinfected patients should be vaccinated against hepatitis B and hepatitis A; vaccines are safe and effective.

An epidemiological survey of hepatitis C virus infection in Italian children in the decade 1990-1999

BACKGROUND

A retrospective-prospective survey of Italian children with hepatitis C virus (HCV) infection was planned in 1998 to explore the epidemiologic features of infection during the past decade.

METHODS

Anti-HCV-positive patients (or HCV RNA-positive infants) aged 1 month to 16 years, consecutively observed in 20 pediatric Institutions, were considered. An anonymous epidemiologic questionnaire based on clinical records was used.

RESULTS

From 1990 through March 1999, 606 patients were observed (296 boys, average age 5.8 years). Maternal infection (46% of cases) and blood transfusions (34%) were the most frequent risk factors. Of 279 infected mothers, 61% did not recall a putative source of infection (by history, many could possibly have had exposure through routes such as therapeutic injections with nondisposable material), whereas 94 (34%) admitted drug abuse, including 49 (17%) coinfected with human immunodeficiency virus (HIV). Only 157 (26%) children were born after 1991: 90% of their mothers were infected (11% were HIV coinfected vs. 25% mothers of older children, P < 0.01).

CONCLUSIONS

Maternal infection is a prominent source of pediatric HCV infection in Italy. The fact that most mothers had a history of covert exposure to HCV, probably through percutaneous routes that are no longer operating, and that the number of those with HIV coinfection has decreased suggests that the frequency of pediatric infection could decrease in the future.

Severe, rapidly progressive human immunodeficiency virus type 1 disease in newborns with coinfections

AIM

To describe a severe form of rapidly progressive HIV-1 infection manifesting in the neonatal period.

METHOD

Prospective cohort study, King Edward VIII Hospital, Durban, South Africa. HIV-1-exposed neonates with hepatosplenomegaly, lymphadenopathy or persistent pneumonia within the first 28 days of life were investigated for perinatal infections. Confirmation of neonatal HIV-1 infection, HIV-1 subtype and clinical outcomes were studied.

RESULTS

Twenty-three (72%) of 32 symptomatic HIV-1-exposed neonates recruited at a mean of 15.2 days were HIV-1-infected. HIV-1 infection was detected in 5 patients who were tested within 48 h of birth, confirming congenital infection. Congenital infection was not excluded in any case. Median neonatal viral load at recruitment was 471,932 copies/ml and median CD4 was 777 cells/mm3. The predominant clinical presentation was growth retardation and prematurity. Perinatal infections detected included: tuberculosis (8), syphilis (6) and cytomegalovirus (10). All of the neonates with perinatal tuberculosis were HIV-1-coinfected. Maternal and neonatal viral load and CD4 at recruitment were not statistically different between the groups with tuberculosis vs. other coinfections. Gag gene sequence analysis confirmed closely aligned HIV-1 subtype C in mothers and neonates. Nineteen (83%) died by 9 months, with a mean age at death of 3.5 months.

CONCLUSIONS

A distinct group of HIV-1-infected babies may clinically manifest in the neonatal period with perinatal coinfections, subsequent rapidly progressive HIV-1 and early death.

[Management of pregnant women infected with HIV at Bichat Hospital between 1990 and 1998: analysis of 202 pregnancies]

OBJECTIVE

To describe medical and obstetrical prenatal care of pregnant women infected by HIV-1 emphasizing the role of cesarean section.

DESIGN

A retrospective study of 202 pregnancies followed between 1990 and 1998 in a french hospital in Paris.

RESULTS

56.9% of the women were born in subsaharian Africa; 80.2% were infected by sexual intercourse and the seropositivity was discovered during the pregnancy in 51% of the cases. Viral coinfections by hepatitis B virus, hepatitis C virus and Human papillomavirus were found respectively in 14.7%, 16.5% and 13% of the pregnancies. Prematurity occurred in 15% of the deliveries. Efficacy of antiretroviral therapy was confirmed in this study: 5.7% of the children were infected despite the antiretrovial treatment versus 19.3% without treatment (p < 0.03). Prophylactic cesarean section was proposed to the patients since 1994; the morbidity of cesarean was 8.8% (69 cesarean sections).

CONCLUSION

The policy of the association of prophylactic cesarean section and monotherapy by Zidovudine is validated by recent studies. The extension of prophylatic cesarean section to all the pregnant women infected by HIV is proposed. However the evaluation of the morbidity of the cesarean section in HIV infected women needs a prospective case-control study.

Vertical human immunodeficiency virus type 1--HIV-1--transmission--a review

Several factors appear to affect vertical HIV-1 transmission, dependent mainly on characteristics of the mother (extent of immunodeficiency, co-infections, risk behaviour, nutritional status, immune response, genetical make-up), but also of the virus (phenotype, tropism) and, possibly, of the child (genetical make-up). This complex situation is compounded by the fact that the virus may have the whole gestation period, apart from variable periods between membrane rupture and birth and the breast-feeding period, to pass from the mother to the infant. It seems probable that an extensive interplay of all factors occurs, and that some factors may be more important during specific periods and other factors in other periods. Factors predominant in protection against in utero transmission may be less important for peri-natal transmission, and probably quite different from those that predominantly affect transmission by mothers milk. For instance, cytotoxic T lymphocytes will probably be unable to exert any effect during breast-feeding, while neutralizing antibodies will be unable to protect transmission by HIV transmitted through infected cells. Furthermore, some responses may be capable of controlling transmission of determined virus types, while being inadequate for controlling others. As occurrence of mixed infections and recombination of HIV-1 types is a known fact, it does not appear possible to prevent vertical HIV-1 transmission by reinforcing just one of the factors, and probably a general strategy including all known factors must be used. Recent reports have brought information on vertical HIV-1 transmission in a variety of research fields, which will have to be considered in conjunction as background for specific studies.

Hepatitis C virus infection as an opportunistic disease in persons infected with human immunodeficiency virus

Hepatitis C virus (HCV) is an RNA virus of the Flaviviridae family and is a major cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Owing to shared routes of transmission, HCV and human immunodeficiency virus (HIV) coinfection are common, affecting approximately one-third of all HIV-infected persons in the United States. In addition, HIV coinfection is associated with higher HCV RNA level and a more rapid progression of HCV-related liver disease, which leads to an increased risk of cirrhosis. HCV infection may also impact the course and management of HIV disease, particularly by increasing the risk of antiretroviral drug-induced hepatotoxicity. Thus, chronic HCV infection acts as an opportunistic disease in HIV-infected persons, because the incidence of infection is increased and the natural history of HCV infection is accelerated in coinfected persons. Strategies to prevent primary HCV infection and to modify the progression of HCV-related liver disease are urgently needed for HIV-HCV-coinfected individuals.

Treatment of chronic hepatitis C virus infection in children

Hepatitis C virus (HCV) infection may occur in infants and children, although it is much less common than it is in adults. The main transmission routes include mother-to-infant transmission, use of HCV infected blood products, unsterile needles or syringes and other invasive procedures. The natural course of HCV infection in children is variable: some (20-40%) develop an acute resolving infection and spontaneous regression occurs in approximately one-third of infants of HCV infected mothers before 2 years of age. Approximately 60-80% of HCV infected children develop a chronic infection with varying degrees of activity and fibrosis, mostly mild during childhood. However, the potential risks of liver cirrhosis and hepatoma during later life are obvious. Interferon is the main agent used to treat HCV infection in children. The response to interferon at the end of 4-12 months of therapy ranges from 25-90%. A sustained response was found in 36-56% of children 6-36 months after the end of therapy. The duration of therapy is recommended to be 12 months. At the end of 3 months, an evaluation of the response is indicated in the majority of children, except those with thalassemia, in whom evaluation of response should be conducted at the end of 6 months of therapy. The benefit of other therapies, such as combination therapy with interferon and ribavirin in children with hepatitis C is currently under investigation.

Hepatitis C epidemiology

Hepatitis C virus infection occurs in all parts of the world. Infection is generally due to percutaneous exposures, though sexual and perinatal transmission may occur. While further study is needed to elucidate the biology of HCV transmission and develop vaccines for prevention, new HCV infections can be reduced by economic development and education regarding blood-borne infections.