GB virus C infection in children with perinatal human immunodeficiency virus infection

BACKGROUND

GB virus C (GBV-C) infection occurs in 20-40% of human immunodeficiency virus (HIV)-infected adults, and coinfection is associated with improved HIV disease outcome.

METHODS

To determine the prevalence of GBV-C infection in children who were perinatally infected with HIV, we conducted a cross-sectional prevalence survey in a cohort of perinatally infected HIV-positive children selected from a large, multicenter observational protocol. A blood specimen was obtained and tested for GBV-C viremia with the use of a qualitative GBV-C RNA assay and screened for past GBV-C infection with enzyme-linked immunosorbent assay to detect antibodies to the GBV-C envelope protein E2 (E2 Ab).

RESULTS

The 354 children who participated in the substudy were relatively healthy, with a median CD4 of 784 cells/mm and median HIV-1 viral load of 1055 copies/mL. The prevalence of GBV-C viremia was 20 of 353 or 5.7% (95% confidence interval, 3.5-8.6%), and the prevalence of E2 Ab was 12 of 354 or 3.4% (95% confidence interval, 1.8-5.8%). GBV-C viremic patients were older than patients without past GBV-C infection (median age, 12.8 years versus 10.7 years). Median CD4 lymphocyte counts were highest in subjects without GBV-C infection and lowest in those with E2 Ab.

CONCLUSIONS

GBV-C prevalence rates are lower in children with perinatal HIV infection than those reported for HIV-infected adults. With the exception of evidence that GBV-C viremic children had lower rates of Centers for Disease Control and Prevention HIV disease category C disease before GBV-C testing, we did not find evidence of improved HIV disease outcome in coinfected patients, but the number of HIV/GBV-C-coinfected children was small.

Amniotic fluid has higher relative levels of lentivirus-specific antibodies than plasma and can contain neutralizing antibodies

BACKGROUND

The in utero transmission rate of HIV-1 is estimated to be 10-15% in the absence of interventions and breastfeeding. Natural protective mechanisms involving lentivirus-specific antibodies may therefore exist to limit in utero transmission of lentiviruses.

OBJECTIVES

HIV-1- and SIV-specific immunoglobulin G (IgG) levels in amniotic fluid samples from humans and rhesus macaques were assessed.

STUDY DESIGN

HIV-1- and SIV-specific immunoglobulin G levels, relative to total IgG concentrations in amniotic fluid samples from humans and rhesus macaques, were determined using a quantitative Western blotting procedure. Amniotic fluid from rhesus macaques was tested for the ability to neutralize SIV infection of CEMX174 cells.

RESULTS

The levels of HIV-1- and SIV-specific immunoglobulin G, relative to total IgG concentrations in amniotic fluid samples from humans and rhesus macaques, were approximately 3-10-fold higher than in plasma. The ability of antibodies in human amniotic fluid samples to neutralize viral infectivity could not be assessed, because zidovidine was present in the samples. Most amniotic fluid samples from rhesus macques not treated with antiretrovirals were able to neutralize SIV infectivity, except for a sample from a SIV positive rhesus whose infant was infected in utero.

CONCLUSIONS

Active immunity to HIV-1 resulting in virus-specific antibodies in amniotic fluid exists, and may be a natural barrier to in utero infection. This may provide hope for stimulating neutralizing antibody via vaccine design.

Hepatitis C Prevalence in Children With Perinatal Human Immunodeficiency Virus Infection Enrolled in a Long-term Follow-up Protocol

OBJECTIVE

To evaluate the prevalence of hepatitis C virus (HCV) infection in children with perinatal human immunodeficiency virus (HIV) infection.

DESIGN

Cross-sectional substudy.

SETTING

Multicenter study from 41 sites in the United States.

PATIENTS

Children with perinatal HIV infection were randomly selected from a large, long-term, follow-up protocol.

MAIN OUTCOME MEASURE

Hepatitis C infection was defined as having positive test results on both HCV antibody and HCV RNA assays.

RESULTS

Five hundred thirty children enrolled in the substudy; definitive HCV test results were available for 525 children. Eighty-three percent were of a minority race or ethnicity. They were equally distributed by sex, had a median age of 10.7 years, and were relatively healthy, with 75% having CD4+ lymphocyte counts greater than 500 cells/mm3. Eight of 525 children (1.5%; 95% confidence interval [CI], 0.7%-3.0%) infected with HIV were coinfected with HCV. In contrast, the rate of HCV infection in a serosurvey of more than 2700 children aged 6 to 11 years from the National Health and Nutrition Examination Survey was 0.2% (95% CI, 0.04%-0.6%). In our study, there were no differences between children coinfected with HIV and HCV and those without HCV infection in terms of demographic characteristics, CD4+ or CD8+ T-lymphocyte counts, HIV 1 RNA levels, preterm or mode of delivery, or liver disease; however, the number of children coinfected with HIV and HCV was small.

CONCLUSION

While HCV prevalence infection rates are low in children with perinatal HIV infection, they are 8 to 10 times higher than reported in HCV serosurveys of children in the United States.

Reported adherence as a determinant of response to highly active antiretroviral therapy in children who have human immunodeficiency virus infection

OBJECTIVE

The complexity of highly active antiretroviral therapy (HAART), with multiple medications, formulations, and dosing intervals, makes adherence challenging. Little is known about the adherence of children to HAART. The objective of this study was to identify correlates of adherence to HAART and the relationship between adherence and study outcomes in a pediatric clinical trial.

METHODS

Pediatric AIDS Clinical Trials Group 377 is a phase I/II randomized trial of 4 HAART regimens in antiretroviral-experienced, clinically stable children aged 4 months to 17 years. The 4 treatment arms include various 3- or 4-drug combinations of d4T, 3TC, nevirapine, ritonavir, and nelfinavir. After informed consent was obtained, 193 children were enrolled between December 1997 and September 1998. Questionnaires were developed to collect subject- or caregiver-reported adherence to study medications and to identify problems associated with medication administration. Every 3 months, the number of doses of each medication missed during the 3 days preceding the study visit was recorded. Full adherence (FA) and non-full adherence were defined as missing no doses and missing at least 1 dose, respectively.

RESULTS

Adherence data from study week 48 or the most recent study visit were available for 125 children (week 48 for 109 children). Overall, 70% of children reported FA and 30% reported non-full adherence. Adherence did not differ by treatment arm, age, or the child's knowledge of his or her human immunodeficiency virus infection status. There was a suggestion that adherence was less for white than nonwhite children (40% vs 73% FA) and did not differ between black and Hispanic children. Rates of FA were 82% for d4T, 79% for 3TC, 83% for nevirapine, 84% for ritonavir, and 68% for nelfinavir. Despite the similar rates of FA, difficulties with taking specific medications were reported most frequently for ritonavir and nelfinavir. These included poor taste, patient refusal, and scheduling problems. Adherence was associated with the virologic response: FA was seen in 92% of children with > or =2 log10 drop in viral load and in 64% with <2 log10 drop in viral load.

CONCLUSION

In children, reported adherence predicts the virologic response to HAART therapy and is a useful measure of adherence. Interventions and regimens to increase adherence to HAART should result in an improved outcome.

Pulmonary infections in children with HIV infection

The epidemic of pediatric acquired immunodeficiency syndrome (AIDS) in the United States, which peaked during the mid-1980s and early 1990s, was characterized by a variety of opportunistic infections in children infected with human immunodeficiency virus (HIV), often as the presenting illness of their HIV infection. Pneumocystis carinii pneumonia (PCP) during infancy was responsible for significant morbidity and mortality, followed by many other opportunistic infections, including recurrent, serious bacterial infections; disseminated cytomegalovirus infection; and disseminated Mycobacterium avium complex (MAC) infection. Many of these infections involve the lower respiratory tract either as a primary site of infection or as one of the sites involved in disseminated disease. Since the mid- to late 1990s, the pediatric HIV epidemic in the United States has witnessed a dramatic decrease in the frequency of most opportunistic infections and other severe manifestations of HIV infection in children, primarily because of lower rates of mother-to-child HIV transmission, development and implementation of guidelines for PCP prophylaxis, and availability of highly active antiretroviral therapy. Far fewer children are at risk for clinical progression of HIV disease and for opportunistic infections. Despite these successful trends, pulmonary opportunistic infections and pulmonary disease remain common clinical manifestations of pediatric HIV disease.