Mitochondrial disorders among infants exposed to HIV and antiretroviral therapy

Setting the research agenda: involving parents in research on children who are HIV-free

INTRODUCTION

There is growing interest in health, developmental and survival outcomes of children who are born HIV-free to women living with HIV (children born HIV-free). To date, the research agenda has been largely determined by researchers, funders and policy makers, with limited involvement of parents, who are key stakeholders. Researchers at UCL Great Ormond Street Institute of Child Health in partnership with community-based organisation 4M Network of Mentor Mothers conducted two workshops with parents in March 2022 to establish research priorities for children born HIV-free, and key considerations for methodological approaches both to research and engagement with the affected communities.

DISCUSSION

When exploring research on children born HIV-free, we consider the following: what aspects of current research are aligned with women and parents' priorities, what is missing and what approaches would be preferred. A holistic approach to research on children born HIV-free should be prioritised, focussing on a breadth of outcomes and how they intersect. Secondary use of existing data sources should be maximised to facilitate this, with a view of monitoring the long-term effects of fetal antiretroviral drug exposure alongside other key health and developmental outcomes. Involving and engaging with parents, and children where possible, must be at the heart of research design to maximise relevance and impact of findings for the affected communities. Potential barriers to engaging with individuals who were children born HIV-free include parental disclosure and individuals not identifying as a child born HIV-free to a mother living with HIV. Stigma-free language must be incorporated into the vocabulary of researchers and other stakeholders, avoiding reference to exposure; we propose the term "children born HIV-free."

CONCLUSIONS

Mothers and parents living with HIV should be involved in research about their children born HIV-free and are key in identifying research priorities so that findings may translate into an impact on their children's health and wellbeing. Meaningful involvement of women living with HIV through trusted community partners is an effective mechanism by which to elicit views on research about their children.

An International Prospective Cohort Study of HIV and Zika in Infants and Pregnancy (HIV ZIP): Study Protocol

Zika virus (ZIKV) infection may adversely affect pregnancies of women living with HIV (WLHIV). Because no study to date has focused on maternal and child effects of HIV and ZIKV co-infection in pregnant women, we undertook the International Prospective Cohort Study of HIV and Zika in Infants and Pregnancy (HIV ZIP). The aims of this two-phase study of pregnant women and their infants are to compare the incidence of ZIKV infection among pregnant women with and without HIV infection and to determine the risk of adverse maternal and child outcomes associated with ZIKV/HIV co-infection at clinical sites in Brazil, Puerto Rico, and the continental United States. Phase I was designed to enroll pregnant women/infant pairs who were: (1) infected with HIV only, (2) infected with ZIKV only, (3) infected with HIV and ZIKV, and (4) not infected with either HIV or ZIKV. A key goal of this phase was to assess the feasibility of enrolling 200 women/infant pairs within a year, with a target of 150 WLHIV, 50 HIV-uninfected women, and a minimum of 20 who were co-infected with HIV and ZIKV. If the feasibility of Phase I proved successful, Phase II would enroll up to 1,800 additional pregnant women/infant pairs to the same four groups. Enrolled women in both phases were to be followed throughout their pregnancy and up to 6 weeks post-partum. Infants were also to be followed for 1 year after birth. To date, Phase 1 data collection and follow-up have been completed. Delineation of possible harmful effects of HIV/ZIKV co-infection will allow the formulation of standard-of-care recommendations to minimize adverse effects but enable the continuation of preventive HIV therapy. Furthermore, while the prospective HIV ZIP study was developed before the COVID pandemic, it is especially relevant today since it can be easily adapted to provide critically important information on the impact of COVID-19 infection or other still unrecognized new agents among pregnant women and their offspring worldwide.

Myocardial peak systolic velocity-a tool for cardiac screening of HIV-exposed uninfected children

HIV-uninfected children exposed prenatally to the virus and to prophylactic antiretroviral therapy are at an uncertain risk of long-term myocardial dysfunction. This study aimed to analyse the structure and function of their ventricles and to identify potential screening tools for this at-risk population. One hundred and fifteen children (77 exposed vs 38 controls) aged between 2.7 and 16.2 years were included. An echocardiographic study was performed where both ventricles' dimensions and systolic functions were evaluated. In the left ventricle, parameters related to diastolic function were also analysed. Tissue Doppler values were determined in the basal state and after passive leg raising. Serologic analysis of amino-terminal pro-B-type natriuretic peptide (NT-proBNP) was carried out. The two groups had identical ventricular sizes and left ventricular diastolic functions. However, contractility assessed by myocardial peak systolic velocity was significantly inferior in the exposed group. These systolic echocardiographic differences were present despite similar values of NT-proBNP in both groups.Conclusion: HIV-exposed uninfected children may be vulnerable to ventricular systolic dysfunction at long term. Cardiovascular surveillance and periodic monitoring of biventricular function are therefore recommended. Myocardial peak systolic velocity may be a useful screening tool for this purpose.What is Known:• Previous studies on HIV-exposed uninfected children subjected prenatally to antiretroviral therapy have alerted to potential long-term cardiovascular toxicity effects on the left ventricle.What is New:• The study gives new insights on ventricular function and morphology in HIV-exposed uninfected children.• Myocardial peak systolic velocities are significantly inferior in this paediatric sub-group, therefore long-term cardiac surveillance is recommended.

Brain microstructural changes support cognitive deficits in HIV uninfected children born to HIV infected mothers

Introduction

Antiretroviral therapy (ART) is considered the most effective way to prevent perinatal transmission of human immunodeficiency virus (HIV). However, there is little knowledge about the effect of ART on the brain of HIV uninfected children born to HIV infected mothers (HUC). The current study evaluated the brain's microstructural integrity, and cognitive function in HUC compared to healthy children born to normal mothers (CHNM) and HIV infected children born to HIV infected mothers (HIC) to investigate the effect of in-utero exposure of ART on cerebral gray and white matter.

Materials and methods

Forty nine HIC, 12 HUC and 18 CHNM underwent neuropsychological (NP) assessment and a brain MRI. Diffusion tensor imaging (DTI) data was used to generate fractional anisotropy (FA) and mean diffusivity (MD) maps. Voxel wise comparison for FA and MD was performed between three groups using an analysis of covariance (ANCOVA) including age and sex as covariates, and correction for multiple comparisons (false discovery rate (FDR), p ​< ​0.05 with minimum extended cluster size, 150 voxels). NP test scores were also compared between three groups using ANOVA with Post Hoc Bonferroni multiple comparison corrections (p ​< ​0.05). Significantly changed FA and MD values in different brain regions in HIC and HUC compared to CHNM were used for correlation analysis with NP test scores using Pearson's correlation.

Results

HIC and HUC groups showed significantly decreased NP test scores in various domain compared to CHNM. Significantly lower NP test scores was observed in HIC than those of HUC. HIC showed decreased FA and increased MD in multiple brain sites as compared to both CHNM and HUC. Decreased FA along with both increased and decreased MD in different brain regions was present in HUC compared to CHNM. Both positive and negative correlation of altered FA and MD values from different brain regions in HIC and HUC with NP test scores was observed.

Conclusion

The presence of brain tissue changes and neurocognitive function deficit in absence of HIV infection in HUC indicates that ART may have a detrimental impact on the developing brain. The findings of the current study underscore the need for screening of ART exposed children for neurodevelopment and cognitive abnormalities at an early stage and call for access to early interventions, and nutritional and care programs.

Metabolic, mitochondrial, renal and hepatic safety of enfuvirtide and raltegravir antiretroviral administration: Randomized crossover clinical trial in healthy volunteers

CONTEXT

Classical antiretroviral agents may acutely impact on metabolic, mitochondrial, renal and hepatic function in HIV-infected and uninfected persons. Fusion and integrase inhibitors are supposed to be safer, but have been scarcely investigated. To avoid any interference with HIV or other antiretrovirals, we assessed markers of these toxicities in healthy adult volunteers treated with Enfuvirtide (T20) or Raltegravir (RAL).

METHODS

Twenty-six healthy participants were randomized to T20/90mg vs. placebo (n = 12) or RAL/400mg vs. placebo (n = 14) every 12h in two 7-day periods separated by a 4-week washout period. Major end-points were changes in lipid profile (total cholesterol, high-density-lipoprotein (HDL)-cholesterol, low-density-lipoprotein (LDL)-cholesterol, triglycerides), insulin resistance (glucose) and mitochondrial toxicity (mitochondrial DNA content-mtDNA-in peripheral blood mononuclear cells). Renal and hepatic toxicity (creatinine, alanine transaminase (AST), alanine aminotransferase (ALT), bilirubin and total plasma proteins) and overall safety were also analysed. Effect of period, treatment, and basal measures were evaluated for each end-point.

RESULTS

Neither T20-administration nor RAL-administration yielded to any statistic significant change in the markers of metabolic, mitochondrial, renal or hepatic toxicity assessed. No symptoms indicative of drug toxicity were neither found in any subject.

CONCLUSIONS

In absence of HIV infection, or concomitant treatment, short-term exposure to T20 or RAL in healthy adult volunteers did not lead to any indicative changes in toxicity markers thus presuming the safe profile of both drugs.

Infant peripheral blood repetitive element hypomethylation associated with antiretroviral therapy in utero

The use of combination antiretroviral therapy (cART) to prevent HIV mother-to-child transmission during pregnancy and delivery is generally considered safe. However, vigilant assessment of potential risks of these agents remains warranted. Epigenetic changes including DNA methylation are considered potential mechanisms linking the in utero environment with long-term health outcomes. Few studies have examined the epigenetic effects of prenatal exposure to pharmaceutical agents, including antiretroviral therapies, on children. In this study, we examined the methylation status of the LINE-1 and ALU-Yb8 repetitive elements as markers of global DNA methylation alteration in peripheral blood mononuclear cells obtained from newborns participating in the Pediatric HIV/AIDS Cohort Study SMARTT cohort of HIV-exposed, cART-exposed uninfected infants compared to a historical cohort of HIV-exposed, antiretroviral-unexposed infants from the Women and Infants Transmission Study Cohort. In linear regression models controlling for potential confounders, we found the adjusted mean difference of AluYb8 methylation of the cART-exposed compared to the -unexposed was -0.568 (95% CI: -1.023, -0.149) and for LINE-1 methylation was -1.359 (95% CI: -1.860, -0.857). Among those exposed to cART, subjects treated with atazanavir (ATV), compared to those on other treatments, had less AluYb8 methylation (-0.524, 95% CI: -0.025, -1.024). Overall, these results suggest a small but statistically significant reduction in the methylation of these repetitive elements in an HIV-exposed, cART-exposed cohort compared to an HIV-exposed, cART-unexposed historic cohort. The potential long-term implications of these differences are worthy of further examination.

Growth and body composition of uninfected children exposed to human immunodeficiency virus: comparison with a contemporary cohort and United States National Standards

OBJECTIVE

To compare growth and body composition of uninfected children exposed to HIV with a contemporary HIV-unexposed group and to US references.

STUDY DESIGN

Uninfected children exposed to HIV under 2 years were enrolled into a longitudinal observational study and unexposed children under 2 years of age in a cross-sectional evaluation. Weights, lengths, head circumferences, skinfold thicknesses, and arm and thigh circumferences were measured and adjusted for age using Centers for Disease Control and National Health and Nutrition Examination Survey standards. Uninfected children exposed to HIV were compared with an unexposed nearest-neighbor matched comparison group. Uninfected children exposed to HIV were compared by age to Centers for Disease Control standards for growth measures and National Health and Nutrition Examination Survey standards for body composition.

RESULTS

One hundred eleven uninfected children exposed to HIV and 82 children not exposed to HIV were evaluated. For the matched comparison for both groups, the mean age was 10 months, 59% were male, and 73% were African American. No statistical differences were found in anthropometric measurements between uninfected children who were or were not exposed to HIV. Uninfected children exposed to HIV were smaller than US standards at birth with mean (SD) weight-for-age and weight-for-length z-scores of -0.39 (1.06); P = .002 and -0.35 (1.04); P = .005, respectively. Over the first 2 years of life, there was a trend toward increasing weight-for-age z-score, length-for-age z-score, and weight-for-length z-score in uninfected children exposed to HIV. Subscapular and triceps skinfolds among uninfected children exposed to HIV were lower than national standards and there was a trend that mid-upper arm circumference decreased over time.

CONCLUSIONS

Growth and body composition of uninfected children who were or were not exposed to HIV were similar. Uninfected children exposed to HIV weigh less at birth and show a pattern of slightly accelerated growth in the first 2 years of life. Uninfected children exposed to HIV had less subcutaneous fat and decreasing mid-upper arm circumference over time when compared with US standards.

Safety of perinatal exposure to antiretroviral medications: developmental outcomes in infants

BACKGROUND

This study evaluated effects of perinatal exposure to antiretroviral (ARV) medications on neurodevelopment of HIV-exposed, uninfected infants.

METHODS

HIV-exposed, uninfected infants (age 9-15 months) enrolled in Surveillance Monitoring for Antiretroviral Therapy Toxicities, a multisite prospective surveillance study, completed the Bayley Scales of Infant and Toddler Development-Third Edition (Bayley-III), assessing cognition, language, motor skills, social-emotional development and adaptive behavior. Linear regression models were used to evaluate associations between Bayley-III outcomes in infants with and without perinatal and neonatal ARV exposure, by regimen (combination ARV [cARV] versus non-cARV), type of regimen (defined by drug class) and individual ARVs (for infants with cARV exposure), adjusting for maternal and infant health and demographic covariates.

RESULTS

As of May 2010, 374 infants had valid Bayley-III evaluations. Median age at testing was 12.7 months; 49% male, 79% black and 16% Hispanic. Seventy-nine percent were exposed to regimens containing protease inhibitors (9% of protease inhibitor-containing regimens also included non-nucleoside reverse transcriptase inhibitors), 5% to regimens containing non-nucleoside reverse transcriptase inhibitors (without protease inhibitor) and 14% to regimens containing only nucleoside reverse transcriptase inhibitors. Overall, 83% were exposed to cARV. No Bayley-III outcome was significantly associated with overall exposure to cARV, ARV regimen or neonatal prophylaxis. For individual ARVs, following sensitivity analyses, the adjusted group mean on the Language domain was within age expectations but significantly lower for infants with perinatal exposure to atazanavir (P = 0.01).

CONCLUSIONS

These results support the safety of perinatal ARV use. Continued monitoring for adverse neurodevelopmental outcomes in older children is warranted, and the safety of atazanavir merits further study.

Blood mitochondrial DNA mutations in HIV-infected women and their infants exposed to HAART during pregnancy

OBJECTIVES

Nucleo(s/t)ide reverse transcriptase inhibitors given to HIV-infected pregnant women to prevent vertical transmission may adversely affect mitochondrial DNA (mtDNA). We hypothesized that HAART-exposed/HIV-uninfected infants may show higher blood mtDNA mutation burden than controls born to HIV-uninfected mothers.

METHODS

Blood was collected from in-utero HIV/HAART-exposed infants and controls, as well as from a subset of their mothers. The presence of mtDNA A→C/T→G (AC/TG) mutations was measured by cloning and sequencing D-loop PCR amplicons. Relationships with maternal characteristics were examined.

RESULTS

No significant difference was found between the percentage of HIV/HAART-exposed infants with AC/TG mutations (N = 15/57, 26.3%) and controls (N = 10/70, 14.3%) before (P = 0.090) or after controlling for covariates (P = 0.058), although a tendency was observed. However, significantly more HIV/HAART-exposed mothers (N = 18/42, 42.9%) harboured AC/TG mutations compared with controls (N = 7/39, 17.9%) before (P = 0.015) and after (P = 0.012) controlling for covariates. AC/TG mutations were more prevalent in HIV/HAART-exposed mothers than in their infants (N = 42, 42.9 vs. 23.8%, P = 0.033), however, this difference disappeared after controlling for covariates. No difference was seen between control mothers and their infants (N = 39, both 17.9%). In HIV/HAART-exposed mothers, only a detectable HIV plasma viral load near delivery predicted AC/TG mutations.

CONCLUSION

Our results suggest that HIV and/or HAART exposure are associated with increased prevalence of AC/TG mtDNA mutations in mothers and show a similar tendency in infants exposed during pregnancy. As accumulation of mtDNA mutations has been linked with aging and age-associated diseases, this may raise concerns in the long term for HIV and HAART-exposed populations.

[Recommendations issued by the Spanish Society of Pediatric Infectious Diseases for the follow-up of the child exposed to the human immunodeficiency virus and to antiretroviral drugs during pregnancy and the neonatal period]

Human immunodeficiency virus vertical transmission in developed countries has dramatically decreased to less than 2% over the last 15 years due to the consecutive implementation of different prophylactic measures, including the use of antiretrovirals, elective cesarean section and refraining from breastfeeding. The follow-up of these otherwise healthy children is, by far, the most common situation related to HIV infection that general pediatricians currently face in routine clinical care in Spain. These recommendations issued by the Spanish Society of Pediatric Infectious Diseases attempt to summarize the main aspects of this follow-up, including birth management, type of feeding, neonatal antiretroviral prophylaxis, HIV infection diagnosis, common early comorbidities, short- and mid-term toxicities, vaccination and other prophylactic measures and long-term follow-up.

Mutational analysis of the mitochondrial tRNA genes and flanking regions in umbilical cord tissue from uninfected infants receiving AZT-based therapies for prophylaxis of HIV-1

A sensitive vertical denaturing gradient gel electrophoresis (DGGE) method, using 13 unipolar psoralen-clamped PCR primer pairs, was developed for detecting sequence variants in the 22 tRNA genes and flanking regions (together spanning approximately 21%) of the human mitochondrial genome. A study was conducted to determine (i) if mitochondrial DNA (mtDNA) polymorphisms and/or mutations were detectable in healthy newborns and (ii) if prepartum 3'-azido-2',3'-dideoxythymidine (AZT) based HIV-1 prophylaxis was associated with significant increases in mtDNA mutations and changes in the degree of heteroplasmy of sequence variants in uninfected infants born to HIV-1-infected mothers. DGGE analysis of umbilical cord tissue (where vascular endothelium and smooth muscle cells are the major source of mtDNA) showed that mtDNA sequence variants were significantly elevated by threefold in AZT-treated infants compared with unexposed controls (P < 0.001), with 24 changes observed in 19/52 (37%) treated newborns (averaging 0.46 changes/subject) versus only eight changes found in 7/55 (13%) unexposed newborns (averaging 0.15 changes/subject). Six distinct sequence variants occurring in unexposed controls were predominately synonymous and homoplasmic, representing previously reported polymorphisms. Uninfected infants exposed to a combination of AZT and 2',3'-dideoxy-3'-thiacytidine and "maternal HIV-1" had a significant shift in the spectrum of mutations (P = 0.04) driven by increases in nonsynonymous heteroplasmic sequence variants at polymorphic sites (10 distinct variants) and novel sites (four distinct variants). While the weight of evidence suggests that prepartum AZT-based prophylaxis produces mtDNA mutations, additional research is needed to determine the degree to which fetal responses to maternal HIV-1 infection, in the absence of antiretroviral treatment, contribute to prenatal mtDNA mutagenesis.