Neurological and developmental effects of HIV and AIDS in children and adolescents

Toxoplasma gondii infections in pediatric neurosurgery

Toxoplasma gondii is a parasite that is estimated to infect one-third of the world's population. It is acquired by ingesting contaminated water and food specially undercooked meat, contact with domestic or wild feline feces, and during pregnancy by transplacental transmission.Immunocompetent hosts are usually asymptomatic, and infection will be self-limited, while those patients whose immune system is debilitated by HIV infection, immunosuppressive therapy, long-term steroid treatment, and fetuses infected during gestation will show evidence of systemic activity which is more severe in the central nervous system and eyes due to insufficient immune response caused by their respective blood barriers. Congenital toxoplasmosis has an estimated incidence of 8% in mothers who were seronegative at the beginning of their pregnancy. Infection in the first trimester may result in spontaneous abortion or stillbirth; however, it is estimated that the highest risk for vertical transmission is during the second and third trimesters when blood flow and placenta thickness favor parasitic transmission.Congenital toxoplasmosis can be detected with periodic surveillance in endemic areas, and with appropriate treatment, the risk of vertical transmission can be reduced, and the severity of the disease can be reversed in infected fetuses.While most infected newborns will show no evidence of the disease, those who suffer active intrauterine complications will present with cerebral calcifications in 8-12% of cases, hydrocephalus in 4-30%, and chorioretinitis in 12-15%. Also, seizure disorders, spasticity, and varying degrees of neurocognitive deficits can be found in 12%.Four distinct patterns of hydrocephalus have been described: aqueductal stenosis with lateral and third ventricle dilatation, periforaminal calcifications leading to foramen of Monro stenosis with associated asymmetrical ventricle dilatation, a mix of aqueductal and foramen of Monro stenosis, and overt hydrocephalus without clear evidence of obstruction with predominant dilatation of occipital horns (colpocephaly).While all patients diagnosed with congenital toxoplasmosis should undergo pharmacological treatment, those presenting with hydrocephalus have traditionally been managed with CSF shunting; however, there are reports of at least 50% success when selected cases are treated with endoscopic third ventriculostomy. Successful hydrocephalus management with appropriate treatment leads to better intellectual outcomes.

Immune Dysregulation Is Associated with Neurodevelopment and Neurocognitive Performance in HIV Pediatric Populations-A Scoping Review

HIV-1 is known for its complex interaction with the dysregulated immune system and is responsible for the development of neurocognitive deficits and neurodevelopmental delays in pediatric HIV populations. Considering that HIV-1-induced immune dysregulation and its association with neurodevelopmental and neurocognitive impairments in pediatric populations are not well understood, we conducted a scoping review on this topic. The study aimed to systematically review the association of blood and cerebrospinal fluid (CSF) immune markers with neurocognitive deficits and neurodevelopmental delays in pediatric HIV populations. PubMed, Scopus, and Web of Science databases were searched using a search protocol designed specifically for this study. Studies were selected based on a set eligibility criterion. Titles, abstracts, and full texts were assessed by two independent reviewers. Data from the selected studies were extracted and analyzed by two independent reviewers. Seven studies were considered eligible for use in this context, which included four cross-sectional and three longitudinal studies. An average of 130 (±70.61) children living with HIV, 138 (±65.37) children exposed to HIV but uninfected and 90 (±86.66) HIV-negative participants were included across the seven studies. Results indicate that blood and CSF immune markers are associated with neurocognitive development/performance in pediatric HIV populations. Only seven studies met the inclusion criteria, therefore, these limited the number of significant conclusions which could have been made by using such an approach. All considered, the evidence suggests that immune dysregulation, as in the case of adult HIV populations, also has a significant association with neurocognitive performance in pediatric HIV populations.

Construct Validity Supports Use of a Novel, Tablet-Based Neurocognitive Assessment for Adolescents and Young Adults Affected by Perinatal HIV from Vulnerable Communities in the United States

Construct validity of novel tablet-based neurocognitive tests (in the NeuroScreen app) measuring processing speed, working memory, and executive functioning in adolescents and young adults (AYA) living with perinatally-acquired HIV (PHIV) and perinatal HIV-exposure without infection (PHEU) was examined. Sixty-two AYA (33 PHIV, 29 PHEU) were recruited from an ongoing longitudinal study (CASAH) in New York City. Medium to large and statistically significant correlations were found between NeuroScreen and gold standard, paper-and-pencil tests of processing speed, working memory, and executive functioning. Results provide partial support for NeuroScreen as an alternative to cumbersome paper-and-pencil tests for assessing neurocognition among HIV-affected AYA.

Effectiveness of Maternal Transmission Risk Stratification in Identification of Infants for HIV Birth Testing: Lessons From Zimbabwe

BACKGROUND

In 2017, Zimbabwe adopted a modified version of the World Health Organization 2016 recommendation on HIV birth testing by offering HIV testing at birth only to infants at "high risk" of HIV transmission. There is limited evidence on the effectiveness of this approach. Our study assessed the sensitivity and specificity of birth testing "high risk" infants only.

METHODS

We conducted a cross-sectional study at 10 health facilities from November 2018 to July 2019. A nucleic acid test for HIV was performed on all HIV-exposed infants identified within 48 hours of life, irrespective of risk status. Univariate and bivariate analyses were used to estimate the performance of the risk screening tool.

RESULTS

HIV nucleic acid test was successfully performed on 1970 infants (95%), of whom 266 (13.5%) were classified as high-risk infants. HIV prevalence for all infants tested was 1.5% (95% CI: 1% to 2%), whereas prevalence among high-risk infants and low-risk infants was 6.8% (95% CI: 3.7% to 9.8%) and 0.6% (95% CI: 0.3% to 1%) respectively. Sensitivity and specificity of the maternal risk screening tool was at 62.1% (95% CI: 44.4% to 79.7%) and 87.2% (95% CI: 85.7% to 88.7%), respectively; positive and negative predictive values were 6.8% (95% CI: 3.7% to 9.8%) and 99.4% (95% CI: 99.0% to 99.7%) respectively.

CONCLUSIONS

Despite high negative predictive value, sensitivity was relatively low, with potential of missing 2 in every 5 HIV infected infants. Given the potential benefits of early ART initiation for all exposed infants, where feasible, universal testing for HIV-exposed infants at birth may be preferred to reduce missing infected infants.

Late diagnosis of human immunodeficiency virus infection is linked to higher rates of epilepsy in children in the Eastern Cape of South Africa

BACKGROUND

Human immunodeficiency virus (HIV)-positive children may present with a wide range of neurological disorders. Among these, epilepsy is of key concern because of its lifelong impact and potential for damage to the central nervous system (CNS). Few studies in developing regions have investigated the prevalence and aetiology of epilepsy in HIV-infected children as a key population.

OBJECTIVES

We describe the prevalence of epilepsy, associated neurological disabilities, immunological status, clinical stage and history of CNS infection at epilepsy diagnosis in a cohort of HIV-infected children receiving antiretroviral therapy (ART) in the Eastern Cape of South Africa.

METHODS

We conducted a retrospective study (2004-2014) at two major referral sites for HIV-infected children diagnosed with epilepsy aged 0-16 years. Eligible subjects were extracted from the electronic medicine bridging access to care in excellence (EMBRACE) Paediatric Cohort using the Paediatric ART Data Management Tool (PADMT). Fixed data fields were interrogated for exposures to antiepileptic drugs. Unstructured 'comments' fields were searched for the terms: epilepsy, seizures, fits and szs, as well as abbreviated versions of common antiepileptic drug names. Eligible subject folders were then retrieved to validate the digital data.

RESULTS

From 2139 children enrolled in the two sites, 53 children were diagnosed with epilepsy (2.48%). In these, the median CD4 count was 591 cells/mm3, and the mean viral load was 4.9 log copies/mL, with undetectable viral loads in only seven children (14.0%). World Health Organization (WHO) clinical HIV stage was available for 46 patients of the sample, with 3, 6, 26 and 11 children graded at stages 1, 2, 3 and 4, respectively. Forty percent children had a history of CNS infection prior to the epilepsy diagnosis, and 55% children were reported to have school problems.

CONCLUSIONS

In this descriptive study, the prevalence of epilepsy among children with HIV was 2.48%, mostly diagnosed in advanced HIV-disease stages. Our findings support the usefulness of early detection and initiation of ART in HIV-infected children in order to reduce the risk of epilepsy. In addition, our study demonstrates that novel techniques are effective in accessing cohort-level data that allow interrogation of both structured and unstructured clinical data.

Early Sites of Virus Replication After Oral SIVmac251 Infection of Infant Macaques: Implications for Pathogenesis

Despite optimization of preventative measures for vertical HIV-1 transmission, daily, roughly 400 infants become HIV infected, most of them through breastfeeding. Viral entry has been presumed to occur in the gastrointestinal tract; however, the exact entry site(s) have not been defined. Therefore, we quantified simian immunodeficiency virus (SIV) RNA and DNA in oral, intestinal, and systemic tissues of 15 infant macaques within 48-96 h after oral SIV_mac251 exposure. SIV DNA was detected as early as 48 h, whereas SIV RNA was typically detected at later time points (72-96 h). Transmitted founder viruses were identical or very similar to a single genotype in the SIV_mac251 challenge stock. SIV RNA and DNA were most frequently found in lymph nodes (LNs) draining the oral cavity and in the ileum. Using in situ hybridization, SIV-infected cells in LNs were exclusively represented by CD3⁺ T cells. SIV RNA and DNA were also detected in the lungs of 20% of the animals, and 60% of the animals had detectable SIV DNA in the cerebrum. The early detection of viral RNA or DNA in lung and brain tissues emphasizes the need for early treatment of pediatric HIV infection to prevent damage not only to the immune system but also to the respiratory tract and central nervous system.

Imaging studies of the HIV-infected brain

Human immunodeficiency virus (HIV) enters the brain early after infecting humans and may remain in the central nervous system despite successful antiretroviral treatment. Many neuroimaging techniques were used to study HIV+ patients with or without opportunistic infections. These techniques assessed abnormalities in brain structures (using computed tomography, structural magnetic resonance imaging (MRI), diffusion MRI) and function (using functional MRI at rest or during a task, and perfusion MRI with or without a contrast agent). In addition, single-photon emission computed tomography with various tracers (e.g., thallium-201, Tc99-HMPAO) and positron emission tomography with various agents (e.g., [18F]-dexoyglucose, [11C]-PiB, and [11C]-TSPO tracers), were applied to study opportunistic infections or HIV-associated neurocognitive disorders. Neuroimaging provides diagnoses and biomarkers to quantitate the severity of brain injury or to monitor treatment effects, and may yield insights into the pathophysiology of HIV infection. As the majority of antiretroviral-stable HIV+ patients are living longer, age-related comorbid disorders (e.g., additional neuroinflammation, cerebrovascular disorders, or other dementias) will need to be considered. Other highly prevalent conditions, such as substance use disorders, psychiatric illnesses, and the long-term effects of combined antiretroviral therapy, all may lead to additional brain injury. Neuroimaging studies could provide knowledge regarding how these comorbid conditions impact the HIV-infected brain. Lastly, specific molecular imaging agents may be needed to assess the central nervous system viral reservoir.

Larger Subcortical Gray Matter Structures and Smaller Corpora Callosa at Age 5 Years in HIV Infected Children on Early ART

Sub-Saharan Africa is home to 90% of HIV infected (HIV+) children. Since the advent of antiretroviral therapy (ART), HIV/AIDS has transitioned to a chronic condition where central nervous system (CNS) damage may be ongoing. Although, most guidelines recommend early ART to reduce CNS viral reservoirs, the brain may be more vulnerable to potential neurotoxic effects of ART during the rapid development phase in the first years of life. Here we investigate differences in subcortical volumes between 5-year-old HIV+ children who received early ART (before age 18 months) and uninfected children using manual tracing of Magnetic Resonance Images. Participants included 61 Xhosa children (43 HIV+/18 uninfected, mean age = 5.4 ± 0.3 years, 25 male) from the children with HIV early antiretroviral (CHER) trial; 27 children initiated ART before 12 weeks of age (ART-Before12Wks) and 16 after 12 weeks (ART-After12Wks). Structural images were acquired on a 3T Allegra MRI in Cape Town and manually traced using MultiTracer. Volumetric group differences (HIV+ vs. uninfected; ART-Before12Wks vs. ART-After12Wks) were examined for the caudate, nucleus accumbens (NA), putamen (Pu), globus pallidus (GP), and corpus callosum (CC), as well as associations within infected children of structure volumes with age at ART initiation and CD4/CD8 as a proxy for immune health. HIV+ children had significantly larger NA and Pu volumes bilaterally and left GP volumes than controls, whilst CC was smaller. Bilateral Pu was larger in both treatment groups compared to controls, while left GP and bilateral NA were enlarged only in ART-After12Wks children. CC was smaller in both treatment groups compared to controls, and smaller in ART-After12Wks compared to ART-Before12Wks. Within infected children, delayed ART initiation was associated with larger Pu volumes, effects that remained significant when controlling for sex and duration of treatment interruption (left β = 0.447, p = 0.005; right β = 0.325, p = 0.051), and lower CD4/CD8 with larger caudates controlling for sex (left β = -0.471, p = 0.002; right β = -0.440, p = 0.003). Volumetric differences were greater in children who initiated ART after 12 weeks. Results suggest damage is ongoing despite early ART and viral load suppression; however, earlier treatment is neuroprotective.

Hippocampal Neuronal Loss in Infant Macaques Orally Infected with Virulent Simian Immunodeficiency Virus (SIV)

The neurological impact of Human Immunodeficiency Virus (HIV) on children includes loss of brain growth, motor abnormalities and cognitive dysfunction. Despite early antiretroviral treatment (ART) intervention to suppress viral load, neurological consequences of perinatal HIV-1 infection persist. Utilizing the pediatric simian immunodeficiency virus (SIV) infection model, we tested the hypothesis that early-life SIV infection depletes neuronal population in the hippocampus. A total of 22 ART-naïve infant rhesus macaques (Macaca mulatta) from previous studies were retrospectively analyzed. Infant macaques were either intravenously (IV) inoculated with highly virulent SIVmac251 at ~1 week of age and monitored for 6-10 weeks, or orally challenged with SIVmac251 from week 9 of age onwards with a monitoring period of 10-23 weeks post-infection (19-34 weeks of age), and SIV-uninfected controls were euthanized at 16-17 weeks of age. We have previously reported that the IV SIVmac251-infected neonatal macaques (Group 1) displayed a 42% neuronal reduction throughout the hippocampal cornu ammonis (CA) fields. The orally-infected infant macaques displayed a 75% neuronal reduction in the CA1 region compared to controls and 54% fewer neurons than IV SIV infants. The CA2 region showed a similar pattern, with a 67% reduction between orally-infected SIV subjects and controls and a 40% difference between IV-and orally-infected SIV groups. In the CA3 region, there were no significant differences between these groups, however both SIV-infected groups had significantly fewer pyramidal neurons than control subjects. There was no correlation between plasma viral load and neuronal populations in any of the CA fields. The loss of hippocampal neurons may contribute to the rapid neurocognitive decline associated with pediatric HIV infection. While each subfield showed vulnerability to SIV infection, the CA1 and CA2 subregions demonstrated a potentially enhanced vulnerability to pediatric SIV infection. These data underscore the need for early diagnosis and treatment, including therapeutics targeting the central nervous system (CNS).

HIV-1 proteins, Tat and gp120, target the developing dopamine system

In 2014, 3.2 million children (< 15 years of age) were estimated to be living with HIV and AIDS worldwide, with the 240,000 newly infected children in the past year, i.e., another child infected approximately every two minutes [1]. The primary mode of HIV infection is through mother-to-child transmission (MTCT), occurring either in utero, intrapartum, or during breastfeeding. The effects of HIV-1 on the central nervous system (CNS) are putatively accepted to be mediated, in part, via viral proteins, such as Tat and gp120. The current review focuses on the targets of HIV-1 proteins during the development of the dopamine (DA) system, which appears to be specifically susceptible in HIV-1-infected children. Collectively, the data suggest that the DA system is a clinically relevant target in chronic HIV-1 infection, is one of the major targets in pediatric HIV-1 CNS infection, and may be specifically susceptible during development. The present review discusses the development of the DA system, follows the possible targets of the HIV-1 proteins during the development of the DA system, and suggests potential therapeutic approaches. By coupling our growing understanding of the development of the CNS with the pronounced age-related differences in disease progression, new light may be shed on the neurological and neurocognitive deficits that follow HIV-1 infection.

Corpus callosum thickness on mid-sagittal MRI as a marker of brain volume: a pilot study in children with HIV-related brain disease and controls

BACKGROUND

Corpus callosum thickness measurement on mid-sagittal MRI may be a surrogate marker of brain volume. This is important for evaluation of diseases causing brain volume gain or loss, such as HIV-related brain disease and HIV encephalopathy.

OBJECTIVE

To determine if thickness of the corpus callosum on mid-sagittal MRI is a surrogate marker of brain volume in children with HIV-related brain disease and in controls without HIV.

MATERIALS AND METHODS

A retrospective MRI analysis in children (<5 years old) with HIV-related brain disease and controls used a custom-developed semi-automated tool, which divided the midline corpus callosum and measured its thickness in multiple locations. Brain volume was determined using volumetric analysis. Overall corpus callosum thickness and thickness of segments of the corpus callosum were correlated with overall and segmented (grey and white matter) brain volume.

RESULTS

Forty-four children (33 HIV-infected patients and 11 controls) were included. Significant correlations included overall corpus callosum (mean) and total brain volume (P = 0.05); prefrontal corpus callosum maximum with white matter volume (P = 0.02); premotor corpus callosum mean with total brain volume (P = 0.04) and white matter volume (P = 0.02), premotor corpus callosum maximum with white matter volume (P = 0.02) and sensory corpus callosum mean with total brain volume (P = 0.02).

CONCLUSION

Corpus callosum thickness correlates with brain volume both in HIV-infected patients and controls.

Clinical associations of white matter damage in cART-treated HIV-positive children in South Africa

A range of factors contributes to white matter damage in vertically infected HIV-positive children. These may include combination antiretroviral treatment (cART) regimen, sociodemographic factors, nutritional-hematological status, HIV-relevant clinical variables, and cognitive functioning. We explored associations between a number of these factors and diffusion tensor imaging (DTI) measures in 50 cART-treated children aged 6 to 15 years. Fractional anisotropy (FA), mean diffusion (MD), radial diffusion (RD), and axial diffusion (AD) were derived from 48 cerebral white matter regions. Significant associations between a number of the clinical variables and white matter integrity were found. Decreased FA, a measure of neuronal damage, was associated with being on second-line cART, low hemoglobin, and younger age. Children with increased MD, a measure of neuronal damage, were younger, had reduced albumin and hemoglobin, and increased viral load. Decreased AD, a measure of axonal damage, was associated with increased viral load and total protein, decreased albumin and hemoglobin, younger age, poorer fronto-striatal cognition, and being on second-line cART. Increased RD, a measure of myelin loss, was associated with younger age, low current CD4 count, low albumin and hemoglobin, and higher viral load and total protein. The current findings underline the possible association of first-line treatment failure with white matter brain dysfunction in pediatric neuroHIV and the importance of examining the effects of HIV disease in the context of treatable clinical variables such as anemia and nutritional status.

Neurocognitive functioning in a Romanian cohort of young adults with parenterally-acquired HIV-infection during childhood

The Romanian cohort can provide valuable information about the effect of chronic HIV-infection and exposure to combined antiretroviral therapy (cART) on the developing brain, based on its unique characteristics: young adults infected parenterally with HIV clade F in the late 1980s and exposed to cART for a decade. We conducted a prospective study using a neuropsychological test battery validated in other international HIV cohorts, in order to evaluate the rate and severity of neurocognitive impairment in a group of young Romanian adults. The 49 HIV-infected (HIV+) participants and the 20 HIV negative (HIV-) controls were similar for age and gender, although the HIV- group tended to be more educated. We found higher cognitive impairment prevalence in the HIV+ group (59.1 %) versus the HIV- group (10 %), and the impairment rate remained significantly higher even when the groups were matched based on the educational level (38.7 % for the HIV+ group vs. 10.0 % for the HIV- controls; p = 0.025). The nadir CD4 count was <200 in 71.4 % of patients, but at the time of neurocognitive assessment, 89.5 % of patients had normal immunological status and 81.8 % undetectable HIV load. Among the HIV-impaired group, 26 % of the participants had syndromic impairment while the other 74 % had asymptomatic neurocognitive impairment. We found a high prevalence of neurocognitive dysfunction in the Romanian young adults growing-up with HIV. The greatest HIV-related cognitive deficits were in the domains of executive and motor functioning, consistent with a frontosubcortical pattern.

Correlating brain volume and callosal thickness with clinical and laboratory indicators of disease severity in children with HIV-related brain disease

BACKGROUND

Objective MRI markers of central nervous system disease severity may precede subjective features of HIV encephalopathy in children. Previous work in HIV-infected adults shows that brain atrophy was associated with low CD4 and with neuropsychological impairment. Significant thinning of the corpus callosum (CC), predominantly anteriorly, was also found in HIV-infected adults and correlated with CD4 levels. These findings have not been tested in children.

PURPOSE

The aim of this study was to determine if brain volume and midsagittal CC linear measurements (thickness and length) on MRI in children with HIV-related brain disease correlate with clinical and laboratory parameters of disease severity.

METHODS

Retrospective MRI analysis in children with HIV-related brain disease used a volumetric analysis software and a semi-automated tool to measure brain volume and callosal thickness/length, respectively. Each measure was correlated with clinical parameters of disease severity including Griffiths Mental Development scores (GMDS), absolute CD4 counts (cells/mm(3)), nadir CD4 (the lowest CD4 recorded, excluding baseline), duration of HAART, and decreased brain growth.

RESULTS

Thirty-three children with HIV-related brain disease were included. Premotor segment of the CC mean thickness correlated with age (p = 0.394). Motor CC maximum thickness correlated significantly with general developmental quotient (p = 0.0277); CC length correlated with a diagnosis of acquired microcephaly (p = 0.0071) and to CD4 level closest to date of the MRI scan (p = 0.04).

CONCLUSIONS

Length of the CC and the "motor CC segment" may represent surrogate clinical biomarkers of central nervous system disease severity and with decreased level of immunity in HIV-infected patients that precede established HIV encephalopathy.

White matter signal abnormalities in children with suspected HIV-related neurologic disease on early combination antiretroviral therapy

BACKGROUND

The natural history and manifestation of HIV-related neurologic disease have been ameliorated by combination antiretroviral therapy (ART). We describe the characteristics of white matter signal abnormalities (WMSA) on magnetic resonance imaging in children with HIV-related neurologic disease.

METHODS

We reviewed magnetic resonance imaging scans of children with suspected HIV-related neurologic disease despite early ART and correlated with clinical, neurodevelopmental data, virologic markers and time on ART. These children were also on the Children with HIV Early Antiretroviral (CHER) trial.

RESULTS

Magnetic resonance imaging scans were performed at a mean age 31.9 months (range 8-54) on 44 children: 10 on deferred and 34 on early treatment arms, commencing ART at mean age of 18.5 and 8 weeks, respectively. Multiple high signal intensity lesions on T2/fluid attenuated inversion recovery were documented in 22 patients (50%), predominantly in frontal (91%) and parietal (82%) white matter. No differences in neurodevelopmental scores comparing children with and without WMSA were found. Neither lesion load nor distribution showed significant correlation with neurodevelopmental scores or neurologic examination. Normal head growth was more common in the WMSA group (P = 0.01). There was a trend for association of WMSA and longer time on ART (P = 0.13) and nadir CD4% (P = 0.08).

CONCLUSIONS

Half of children referred with HIV-related brain disease had WMSA on T2/fluid attenuated inversion recovery. Our findings of the association with normal head growth and duration of ART require further study. We suspect that WMSA can occur early and that initiating ART by 8 weeks of life may be too late to prevent HIV from entering the central nervous system.

Perinatally HIV-infected youth presenting with acute stroke: progression/evolution of ischemic disease on neuroimaging

BACKGROUND AND PURPOSE

Although HIV infection is decreasing in infants and children, there is a steady cohort of perinatally HIV-infected (PHIV) children that are growing older. Increased risk of acute stroke has been reported in PHIV children. Our goal was to evaluate evolution/progression of neuroimaging findings in PHIV youth initially presenting with acute stroke.

MATERIALS AND METHODS

The medical records of PHIV pediatric patients (n = 179) from 1996 to 2010 were reviewed and patients with clinical documentation of acute stroke referred to the neuroradiology service were eligible for the study. Neuroimaging (brain CT, MRI, and MRA) and charts were evaluated; clinical and neuroimaging findings at the initial acute stroke and at the last presentation to the neuroradiology service were documented and analyzed.

RESULTS

Eight PHIV patients with clinical findings of acute stroke referred to the neuroimaging were identified. CT and MRI findings of infarction were found in all (8/8) patients in their first and/or last neuroimaging study; including basal ganglia-thalami (BGT) infarction (7/8), focal cortical infarction (4/8), and internal capsule infarction (4/8). Imaging depicted cortical atrophy (5/8), BGT calcification (3/8), and posterior reversible encephalopathy syndrome, wallerian degeneration, and periventricular white matter hyperintense T2 signal each in one patient. No tumors or infectious masses, cysts or abscesses were identified. Subsequent available neuroimaging revealed progression of the cerebrovascular disease in seven patients, 5/7 in the absence of new clinical signs or symptoms. Segmental occlusion, narrowing or narrowing/dilatation in the circle of Willis was found in 6/6 patients who underwent MR angiography and fusiform aneurysms were detected in three of them, a saccular aneurysm in one patient.

CONCLUSION

Asymptomatic progression of cerebrovascular disease was found in PHIV adolescents with prior stroke. These findings may have implications for long-term risk and outcomes for this patient population. There should be a low threshold to evaluate for CNS pathology even with minor symptoms in this population. More studies are necessary to determine if there is a benefit from screening of asymptomatic patients.

Intra-uterine exposure to maternal opiate abuse and HIV: the impact on the developing nervous system

BACKGROUND

Both intra-uterine exposure to maternal drugs and HIV are known to adversely affect the developing central nervous system.

AIMS

(1) To describe the quality of GMs in infants who were intra-uterinely exposed to maternal opiate abuse and HIV; and (2) to analyze to what extent (a) perinatal events, (b) status of HIV-infection, and (c) the quality of GMs are associated with the neurodevelopmental outcome at 2 to 3years of age.

PATIENTS AND METHOD

Seventy-seven children intra-uterinely exposed to both maternal opiate abuse and HIV in utero (41 boys and 36 girls; 39 born preterm) were videoed twice: first during the first 2months after term (writhing GMs) and again at 3-5months (fidgety GMs). Neurodevelopmental outcome was assessed at 2-3years of age.

RESULTS

Thirty-eight infants showed abnormal writhing GMs; 25 infants had abnormal or absent fidgety movements; 22 children had an adverse neurodevelopmental outcome. The association between GM trajectories and outcome revealed a Cramer-V=0.75 (p<0.001). Those infants with active HIV-infection (n=10) did not differ from the 67 infants who were HIV-exposed but uninfected with respect to their GM quality or outcome.

CONCLUSIONS

Serial assessment of GMs in infants who were intra-uterinely exposed to maternal opiates and to HIV can be utilized for early identification of infants at a higher risk for later deficits and needing early intervention.

Two-dimensional 1H MR spectroscopy of the brain in human immunodeficiency virus (HIV)-infected children

PURPOSE

To measure cerebral metabolites in brains of human immunodeficiency virus (HIV)-infected patients using two-dimensional (2D) proton ((1)H) magnetic resonance spectroscopy (MRS), which enables more sensitive detection of metabolites at lower concentrations and delineation of the components of the different choline (Ch) groups in the frequency domain when compared to one dimensional (1D) (1)H-MRS.

MATERIALS AND METHODS

We examined metabolite/creatine (Cr) and metabolite/Ch ratios in the left frontal brain of 10 HIV-infected (mean age 13.7 +/- 4.7 years) and 11 control (mean age 15.3 +/- 4.6 years) adolescents and children using 2D localized chemical shift correlated spectroscopy (L-COSY). The integrated volume under each 2D metabolite peak was calculated with reference to the diagonal creatine methyl peak (Cr_d) or the diagonal choline trimethylamine peak (Ch_d).

RESULTS

In the HIV-infected patients, myoinositol (mI)/Cr_d (P = 0.009) and mI/Ch_d (P = 0.006) were elevated. The ratios of the following metabolites were also significantly elevated (P < 0.05): mI-Ch/Cr_d, gamma-aminobutyrate (GABA)/ Cr_d, GABA/Ch_d, threonine-lactate (Thr-Lac)/Cr_d, Thr-Lac/Ch_d, and N-acetyl aspartate (NAA)/Cr_d.

CONCLUSION

We have demonstrated for the first time the feasibility of 2D-MRS in HIV-infected children and adolescents to assess cerebral metabolites and found elevated mI and elevated GABA, in the left frontal brain of clinically stable HIV-infected patients. A larger study population is needed to confirm these pilot GABA findings.

Does HIV-1/AIDS-associated frontotemporal neuropathology following perinatal infection influence the development of moral behaviour?

While HIV encephalopathy and the AIDS dementia complex are considered hallmark neurologic manifestations of HIV-1 infection, increasing evidence of a continuum of nervous system involvement indicates the existence of an unrecognized number of individuals with milder, mostly cognitive and/or behavioural effects. Questions are raised whether HIV-related frontotemporal neuropathology during critical developmental stages could affect development of the brain networks documented to be involved in moral decisions, and whether this could contribute to the phenomenon of delinquency in an unknown percentage of the current generation of approximately 18-25 year old survivors of early childhood or vertically acquired HIV infection. Carefully planned and executed long term, prospective controlled studies using environmental, clinical, neurological, behavioural, genetic, immune and functional neuroimaging correlates would be required to elucidate whether HIV-specific neuropathology could indeed act as an independent risk factor for the development of a frontotemporal sociopathy syndrome. If such an association is proven, the accelerated development of neurospecific therapies should be a priority, especially for clinically and immunologically stable HIV-infected children. It may be necessary to institute such treatment as early as possible in perinatally infected cases, and maybe even during intrauterine life if HIV-1 is demonstrated to also act as a neurobehavioural teratogen for the developing fetal brain. It may, however, prove to be difficult to separate primary neurobiological from environmental factors, since the epigenetic effects on the host genome of retroviral insertion influencing behavioural gene expression characteristics, and altered gene expression following early life stresses may involve overlapping neurodevelopmental gene regulatory networks. In the meantime it remains necessary to prevent or ameliorate frequent neuropsychiatric morbidity from whatever causes.

Neurodevelopmental functioning in HIV-infected infants and young children before and after the introduction of protease inhibitor-based highly active antiretroviral therapy

OBJECTIVES

The purpose of this work was to examine the effects of HIV infection and the impact of highly active antiretroviral treatment with protease inhibitors on neurodevelopmental functioning during the first 3 years of life.

PATIENTS AND METHODS

Pediatric AIDS Clinical Trials Group 219/219C is a longitudinal cohort study that has enrolled HIV-infected (HIV+) and HIV-exposed but uninfected (HIV-) infants and children since 1993. Longitudinal profiles of neurodevelopmental functioning as measured by the Bayley Scales of Infant Development were compared by HIV-infection status before and after the availability of highly active antiretroviral therapy with a protease inhibitor and within infants with Bayley tests available before and after initiating protease inhibitor therapy.

RESULTS

In the pre-protease inhibitor era, mean mental and motor scores in HIV+ (n = 54) infants <1 year of age were significantly lower than those among HIV- infants (n = 221) and remained lower up to 2 years of age. After protease inhibitors became available, mean mental and motor functioning of HIV+ infants (n = 91) <1 year of age were still significantly lower than those of HIV- infants (n = 838). However, against a background of declining scores among the HIV- infants, there was evidence of limited improvement in the HIV+ infants relative to their uninfected peers. Among infants who had Bayley II evaluations before and after starting a protease inhibitor, there was a trend to improved mental and motor scores after initiation of protease inhibitor therapy.

CONCLUSIONS

The suppression of systemic viral replication and subsequent substantial improvements in survival and immunologic status brought about by highly active antiretroviral therapy have been followed by limited improvements in neurodevelopmental functioning in young children. Additional longitudinal research is needed to better understand the role of antiretroviral therapy as well as the impact of genetic and environmental factors on neurodevelopmental functioning in children affected by HIV.

Mutations in genes encoding ribonuclease H2 subunits cause Aicardi-Goutières syndrome and mimic congenital viral brain infection

Aicardi-Goutières syndrome (AGS) is an autosomal recessive neurological disorder, the clinical and immunological features of which parallel those of congenital viral infection. Here we define the composition of the human ribonuclease H2 enzyme complex and show that AGS can result from mutations in the genes encoding any one of its three subunits. Our findings demonstrate a role for ribonuclease H in human neurological disease and suggest an unanticipated relationship between ribonuclease H2 and the antiviral immune response that warrants further investigation.

Interaction between Plasmodium falciparum and human immunodeficiency virus type 1 on the central nervous system of African children

Plasmodium falciparum and human immunodeficiency virus type 1 (HIV-1) infections are common in children living in sub-Saharan Africa (SSA). Both of these pathogens affect the central nervous system (CNS). Most HIV-1 infection of children in this region is acquired from infected mothers, particularly during breast-feeding and at the time of delivery. Over a third of children infected by birth will have died before their first birthday, before overt CNS manifestations have developed. The most common manifestations of primary CNS infection include neurodevelopmental delay, impaired brain growth, motor deficits, and behavioral problems. These deficits may also result from infections, neoplasm, or stroke. Cognitive impairments become more evident if the child survives for longer, but in Africa, children rarely survive past their fifth birthday. In malaria endemic areas, severe falciparum malaria usually develops after 6 months of age, and most of the CNS manifestations are more common in children over 1 year old. About 11% of children develop neurological deficits following cerebral malaria, most of which improve within 2 years of the insult. However, up to 24% of children may have neurocognitive impairments following severe malaria. The effect of milder malaria and coincidental parasitization on cognitive function is unknown. Other comorbidities that are common in SSA, such as malnutrition or micronutrient deficiencies, may influence children's neurodevelopment. The coinfection of malaria and HIV-1 may aggravate the neurodevelopmental impairments documented in these children. However, to date there are little published data, although it may have a profound effect of children living in SSA.

Use of Intrathecal Baclofen in a Child With Spastic Paraparesis Related to Human Immunodeficiency Virus Infection: A Case Report

This case report describes a 2-year treatment course of a 6-year-old with spastic paraparesis due to human immunodeficiency virus (HIV) encephalopathy. She continued to develop worsening musculoskeletal problems and a decline in mobility despite aggressive antispasticity interventions. In addition to meeting the usual clinical criteria for treatment with continuous intrathecal baclofen (ITB), she was believed to be an appropriate candidate for ITB because of adequate treatment of her HIV infection and associated overall low risk of mortality. For over 12 months, she has been successfully treated with ITB and has not developed any complications related to her HIV infection. To my knowledge, this is the first reported successful treatment of spasticity with ITB in a patient with stable HIV infection.

Health, neurologic, and cognitive status of HIV-infected, long-surviving, and antiretroviral-naive Ugandan children

OBJECTIVE

The purpose of this study was to assess the health status and school-age neurodevelopmental progress of antiretroviral treatment (ARVT)-naive, HIV-infected Ugandan children who had been followed as part of cohorts of children born to HIV-infected and -noninfected mothers between 1989 and 1993.

METHODS

Twenty-eight children, aged 6 to 12 years, vertically infected with HIV-1 and never treated with ARVT were evaluated in terms of health status, neurologic, and psychometric testing. A randomly selected group of 42 seroreverters and 37 HIV-1 negative children who were age- and gender-matched and who had been followed in the same cohorts were evaluated also. The families studied were homogenous in their socioeconomic status. None of the mothers or children had received ARVT or been exposed to illicit drugs.

RESULTS

The HIV-infected children showed significantly more evidence of acute malnutrition. They also had more illness, especially parotitis, otitis media, upper respiratory infections, and lymphadenopathy. However, they did not differ significantly in neurologic and cognitive assessments when compared with age- and gender-matched seroreverter and HIV-negative children. They were in the normal range with respect to neurologic and psychometric development measures.

CONCLUSIONS

These children seem to represent a significant subgroup of HIV-infected child survivors for whom the progress of the disease is less aggressive throughout early life. Given the fact that many infants, especially in developing countries, continue to be born without the benefit of perinatal ARVT, there will likely continue to be many older HIV-infected children in the same situation as those described in this follow-up study. They will not have been recognized as being HIV-infected. It is important that such children be identified and offered access to ARVT and other appropriate support services.

Neurocognitive outcomes in pediatric HIV

Cognitive impairment has long been associated with the natural history of HIV among vertically infected children. In children, HIV may have a direct or indirect impact on the developing brain, may lead to global or highly specific consequences, and may be responsible for minor cognitive consequences or, conversely, long-term and severe disability. This differential impact is related to multiple factors that influence the individual expression of the virus in any given child. This review provides an overview of the relevant literature on neurocognitive outcomes for infants, children, and youth vertically infected with HIV, with attention to those factors impacting neurocognitive outcome within a developmental framework. Research findings in both the era preceding and following the introduction of combined therapies are reviewed, since many of the issues identified prior to state-of-the-art treatment currently available in the United States and other developed countries still apply in much of the developing world. Intervention issues and directions for future research are also discussed.

Youths and HIV/AIDS: psychiatry's role in a changing epidemic

OBJECTIVE

To review the past 10 years of published research on human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) in the United States, including psychosocial and psychiatric risk factors, epidemiology, biology, neurocognitive and psychiatric sequelae, disclosure issues, prevention strategies, and biological and behavioral treatments.

METHOD

Researchers reviewed the English-language literature with a focus on child and adolescent risk factors associated with HIV/AIDS, prevention, and treatment.

RESULTS

Substantial scientific advances have occurred over the past two decades leading to decreased morbidity and mortality in the United States from AIDS-related opportunistic infections. At the same time, rates of HIV infection are increasing in teenagers, young women, and minorities, and growing numbers of youths are living with an infected family member. Understanding HIV risk behavior requires a broad theoretical framework. Comprehensive HIV prevention programs have led to reduced risk behavior among HIV-affected youths and teens at risk of infection. Biological and behavioral treatments of HIV infection continue to evolve and have led to longer life span, improved quality of life, and fewer psychiatric problems.

CONCLUSIONS

HIV/AIDS has significant mental health implications, and psychiatry can play a critical role in curbing the epidemic. With minimal effort, mental health professionals can adapt and apply the strategies that they use to treat psychiatric symptoms to prevent HIV transmission behaviors.

Short communication: HIV infection, antiretrovirals, and apoptosis: studies on skeletal muscle

Increased apoptosis in CD4+ T lymphocytes plays an important role in the pathogenesis of HIV infection and it has also invoked some HIV-related as well as antiretroviral-related adverse events. We assessed whether increased apoptosis is also present in the skeletal muscle of HIV-infected patients. We included 36 consecutive individuals, 18 without (group A) and 18 with HIV infection. The latter group consisted of five asymptomatic antiretroviral-naive HIV-infected individuals (group B), six asymptomatic HIV-infected individuals on highly active antiretroviral therapy (HAART, group C), and seven HIV-infected individuals on HAART with lipodystrophy (group D). Immunohistochemical reaction using deoxyribonucleotidyltransferase-mediated- dUTP-biotin nick-end labeling (TUNEL) was performed on skeletal muscle samples. None of the uninfected patients (group A) showed data of increased apoptosis, while 16 out of 18 infected patients did (p < 0.001). All subgroups of infected subjects (groups B-D) showed a significant increase of apoptosis in TUNEL with respect to uninfected individuals, but the comparison between the different subgroups of infected patients did not reveal significant differences. We conclude that skeletal muscle of HIV-infected patients exhibits increased apoptosis compared with that of uninfected patients, but the role of HAART in inducing apoptosis remains to be established.

Sonographic lenticulostriate vasculopathy in infancy with tic and other neuropsychiatric disorders developed after 7 to 9 years of follow-up

On gray-scale transfontanel sonography, the small arteries supplying the basal ganglia are indistinct from the brain parenchyma in normal infants. Bright linear 'branched candlestick' stripes in these regions, suggesting sonographic lenticulostriate vasculopathy, were reported in more than 200 infants in the English literature; including 34 our own patients. To identify its long-term outcome, a prospective study was accomplished on our 34 infants with sonographic lenticulostriate vasculopathy which included 13 cryptogenic cases and 21 with distinct etiologies. At the age of 7 to 9 years in the cryptogenic group, 7 in 13 patients developed tics, attention deficits, hyperactivity, and/or obsession/compulsion; while in the symptomatic group only 2 of 21 patients had tics. The rate of mortality (33% vs. 0%), developmental delay (24% vs. 8%), mental retardation (24% vs. 0%), and neurologic deficits (29% vs. 0%) were significantly higher in the symptomatic group than the cryptogenic group. Comparatively, the occurrence rate of attention deficit-hyperactivity disorder (10% vs. 54%), tics (10% vs. 38%), and obsessive-compulsive disorder (5% vs. 13%) were significantly lower in the symptomatic group than the cryptogenic group. The rates of these neuropsychiatric disorders were 10% in the symptomatic group and 54% in the cryptogenic group. We concluded that idiopathic sonographic lenticulostriate vasculopathy in infancy may predict development of neuropsychiatric disorders later in childhood.

Neuroimaging in spasticity and movement disorders

Advances in neuroimaging provide unique opportunities to evaluate brain structure, biochemistry, and function. Although a number of imaging techniques have been used in newborns, cranial ultrasonography in premature infants and nuclear magnetic resonance modalities, including magnetic resonance imaging and diffusion-weighted imaging, in high-risk term infants are of foremost benefit. Interpretation is based on knowledge of characteristic imaging findings in specific childhood neurologic disorders and an understanding of differential diagnosis in cerebral palsy syndromes, such as spastic diplegia and various subtypes of extrapyramidal cerebral palsy. This review focuses on imaging studies that can be effectively used in at-risk infants and in children with spasticity and movement disorders to refine diagnosis and guide therapeutic interventions.

Zidovudine: a review of its use in the management of vertically-acquired pediatric HIV infection

Zidovudine is a thymidine analog that, after intracellular phosphorylation to zidovudine triphosphate metabolite, inhibits HIV-specific reverse transcriptase and terminates proviral DNA. Zidovudine administered to mildly symptomatic women with HIV infection in the antepartum (100mg orally 5 times/day), intrapartum (2 mg/kg intravenously over 1 hour then 1 mg/kg/h) and then to the neonate for 6 weeks (2 mg/kg), significantly reduced the rate of vertical HIV transmission by about two thirds, in the absence of breast-feeding (The Pediatric AIDS Clinical Trials Group 076 trial, standard protocol). Shorter zidovudine regimens, reduced the risk of transmission of HIV by 50% in a non-breast-feeding population and by about 37% in breast-feeding populations. Zidovudine (standard protocol) in combination with lamivudine was superior to zidovudine alone. A short oral zidovudine regimen was not as effective as a two-dose oral nevirapine regime, although the combination of short-course zidovudine plus lamivudine was as effective. Suppression of viral replication in neonates, infants and children has been achieved with zidovudine when used in triple-therapy regimens that include other antiviral drugs. Results from a trial of treatment-naive children indicate that the antiviral efficacy of combinations of zidovudine and lamivudine or abacavir, given with the protease inhibitor nelfinavir, is superior to treatment with this combination minus nelfinavir. When zidovudine was used in other highly active antiretroviral therapy regimens significant improvements in surrogate markers were consistently seen. Changing to ritonavir-containing regimens was superior to changing to treatment with two new nucleoside reverse transcriptase inhibitors. Short- and long-term (up to 5.6 years) outcomes from clinical trials showed that prenatal and neonatal exposure to zidovudine was generally well tolerated with the exception of mild anemia that resolved spontaneously after treatment cessation. Zidovudine was generally well tolerated as monotherapy in clinical trials of pediatric patients with HIV infection, and adverse events were similar to those reported in adults, with anemia and neutropenia being the most common.

CONCLUSION

Zidovudine, as monotherapy or in combination with other antiretroviral agents, remains a first-choice therapy for the prophylaxis of mother-to-child HIV transmission as shown by substantial reductions in transmission rates. Where feasible, the optimal strategy to prevent vertical transmission is to combine drug therapy with Cesarean section delivery and no breast-feeding. In addition, zidovudine in combination with another nucleoside analogue and a protease inhibitor is a first- or second-choice therapy for the treatment of pediatric HIV infection as significant and sustained reductions in viral load have been shown in both plasma and cerebrospinal fluid.