HIV-Exposed Uninfected Infants in Zimbabwe: Insights into Health Outcomes in the Pre-Antiretroviral Therapy Era

Comparison of Feeding Practices and Growth of Urbanized African Infants Aged 6-12 Months Old by Maternal HIV Status in Gauteng Province, South Africa

Appropriate feeding practices are protective against malnutrition and poor growth. We compared feeding practices and growth in HIV-exposed-uninfected (HEU) and HIV-unexposed-uninfected (HUU) between 6-12 months of age in urbanized African infants in South Africa. A repeated cross-sectional analysis was used to determine differences in infant feeding practices and anthropometric measures by HIV exposure status at 6, 9, and 12 months in the Siyakhula study. The study included 181 infants (86 HEU; 95 HUU). Breastfeeding rates were lower in HEU vs. HUU infants at 9 (35.6% vs. 57.3%; p = 0.013) and 12 months (24.7% vs. 48.0%; p = 0.005). Introduction to early complementary foods was common (HEU = 16.2 ± 11.0 vs. HUU = 12.8 ± 9.3 weeks; p = 0.118). Lower weight-for-age Z-scores (WAZ) and head circumference-for-age Z-scores (HCZ) were found in HEU infants at birth. At 6 months, WAZ, length-for-age Z-scores (LAZ), HCZ, and mid-upper-arm circumference-for-age Z-scores (MUACAZ) were lower in HEU vs. HUU infants. At 9 months, lower WAZ, LAZ, and MUACAZ were found in HEU vs. HUU infants. At 12 months, lower WAZ, MUACAZ, and weight-for-length Z-scores (-0.2 ± 1.2 vs. 0.2 ± 1.2; p = 0.020) were observed. HEU infants had lower rates of breastfeeding and poorer growth compared to HUU infants. Maternal HIV exposure affects the feeding practices and growth of infants.

Risk factors for stunting in children who are HIV-exposed and uninfected after Option B+ implementation in Malawi

Evidence suggests children HIV-exposed and uninfected (CHEU) experience poor growth. We analysed child anthropometrics and explored factors associated with stunting among Malawian CHEU. Mothers with HIV and their infants HIV-exposed were enroled in a nationally representative prospective cohort within the National Evaluation of Malawi's Prevention of Mother-to-Child HIV Transmission Programme after Option B+ implementation (2014-2018). Anthropometry was measured at enrolment (age 1-6 months), visit 1 (approximately 12 months), and visit 2 (approximately 24 months). Weight-for-age (WAZ) and length-for-age (LAZ) z-scores were calculated using World Health Organization Growth Standards; underweight and stunting were defined as WAZ and LAZ more than 2 standard deviations below the reference median. Multivariable logistic regression restricted to CHEU aged 24 months (±3 months) was used to identify factors associated with stunting. Among 1211 CHEU, 562/1211 attended visit 2, of which 529 were aged 24 months (±3 months) and were included. At age 24 months, 40.4% of CHEU were stunted and/or underweight, respectively. In multi-variable analysis, adjusting for child age and sex, the odds of stunting were higher among CHEU with infectious disease diagnosis compared to those with no diagnosis (adjusted odds ratio = 3.35 [95% confidence interval: 1.82-6.17]), which was modified by co-trimoxazole prophylaxis (p = 0.028). Infant low birthweight was associated with an increased odds of stunting; optimal feeding and maternal employment were correlated with reduced odds. This is one of the first studies examining CHEU growth since Option B+. Interventions to improve linear growth among CHEU should address their multi-faceted health risks, alongside maternal ART prescription, and follow-up of mother-child pairs.

HIV-Infektion und -Exposition bei Kindern und Jugendlichen

Hintergrund

Seit 1997 steht mit den antiretroviralen, kombinierbaren Wirkstoffen eine effektive Prävention und Behandlung einer Infektion mit dem „human immunodeficiency virus“ (HIV) zur Verfügung.

Fragestellung

Was wurde in dieser Zeit durch die Transmissionsprophylaxe und Behandlung der HIV-Infektion bei Kindern in Deutschland erreicht?

Material und Methoden

Darstellung der Entwicklung der Transmissionsprophylaxe und der epidemiologischen Erhebungen des Robert Koch-Instituts, Darstellung der Arzneimittelentwicklung und der Leitlinien zur antiretroviralen Therapie (ART) bei Kindern und Jugendlichen, Vorstellung von Erhebungen der deutschen Kinder-HIV-Kohorte („German pediatric and adolescent HIV cohort“, GEPIC).

Ergebnisse

Die Einführung der HIV-Testung Schwangerer hat die regelmäßige ART HIV-positiver Schwangerer und die Einführung von transmissionsmindernden Maßnahmen möglich gemacht. Damit konnte das Risiko der vertikalen Transmission von ca. 30 % auf < 1 % gesenkt werden. Gegenwärtig wird untersucht, ob HIV-exponierte Kinder ohne Risiko gestillt werden können. Die ART bei Kindern hat die Überlebensraten sowie die körperliche und die kognitive Entwicklung HIV-positiver Kinder entscheidend verbessert. Neue Wirkstoffe haben ein günstigeres Nebenwirkungsprofil. In Deutschland konnten die WHO-Ziele, bei 90 % der Kinder eine vollständige Suppression der Viruslast zu erzielen, erreicht werden. Späte Diagnosen sind bei Kindern und Jugendlichen weiterhin mit schweren Infektionen verbunden. Die HIV-Infektion ist weiterhin eine Erkrankung mit Stigma geblieben und wird deswegen meist gegenüber den Kindern und ihrer Umwelt geheim gehalten.

Schlussfolgerung

Mit der jetzt möglichen Transmissionsprophylaxe und Therapie gelingt es, Transmissionen weitgehend zu verhindern und HIV-positiven Kindern bei frühzeitiger Diagnose ein weitgehend gesundes Leben zu ermöglichen. Das Ziel, dass Kinder ihre Krankheit ohne Angst kennen und nennen können, ist nach wie vor nicht erreicht.

Cardiovascular effects of intrauterine exposure to maternal HIV and antiretroviral therapy in Ethiopian infants followed from fetal life

OBJECTIVE

To assess cardiovascular effects of in-utero HIV and antiretroviral treatment (ART) exposure on offspring of HIV-positive mothers in Ethiopia.

DESIGN

HIV-positive and HIV-negative pregnancies were identified from a prospective cohort of women recruited at their first antenatal care visit in Ethiopia, using a nested case-control design.

METHODS

Fetal standard ultrasound and echocardiography were performed at 2237 weeks of pregnancy to assess fetal biometry and cardiac structure. Postnatal cardiovascular evaluation, including echocardiography and vascular assessment, was performed at 6 months of age. Cardiovascular data were correlated to HIV serostatus, antiretroviral drug exposure and HIV-unrelated maternal characteristics.

RESULTS

Fetuses from 29 HIV-positive and 67 HIV-negative women paired by gestational age at scan were included. Among HIV-positive women, 25 were on ART before conception, and 4 initiated ART during pregnancy. Estimated fetal weight was similar in both groups [mean 1873 g (standard deviation; SD 569) vs. 1839 g (SD 579) P = 0.79, respectively]. Fetal cardiac morphometry was similar with regard to maternal HIV serostatus: cardiothoracic ratio mean 0.26 (SD 0.05) vs. 0.25 (SD 0.06), P = 0.48; and septal wall thickness mean 4.03 mm (SD 0.58) vs. 3.98 mm (SD 0.70), P = 0.94. No significant cardiovascular differences were detected postnatally according to maternal HIV serostatus: septal wall thickness mean 5.46 mm (SD 0.65) vs. 5.49 (SD 0.89); P = 0.896; isovolumic relaxation time 55.08 ms (SD 6.57) vs. 56.56 (SD 6.74); P = 0.359.

CONCLUSION

In offspring of Ethiopian women, intrauterine exposure to HIV and ART were not associated with cardiovascular changes from fetal life up to infanthood.

Impact of HAART Therapy and HIV Infection over Fetal Growth-An Anthropometric Point of View

Human immunodeficiency virus (HIV) infection cannot be completely eliminated from the body because the virus integrates its genetic code into that of the host cell. The prevalence of pregnancy in women with HIV infection has increased due to the efficacy of antiretroviral therapy (ART). Placental insufficiency is associated with a reduction in blood flow and circulatory redistribution, resulting in fetal hypoxia and nutrient deprivation as a consequence of an altered placental function, and it can result in a lower birthweight. The aim of the study was to determine the combined effect of HIV infection and ART on the anthropometric parameters of infants born to HIV-positive pregnant women under ART compared to the values of these parameters in a control group of infants born to healthy mothers. There are no significant differences between the two groups in terms of gestational age at birth. We found a statistically significant lower birth weight in infants born from HIV-positive mothers under ART, with 3041 g in the control group compared to 2758 g in the group of HIV positive pregnant women (p < 0.01). There were statistically significant differences in all anthropometric parameters, these showing higher values in the control group (seronegative pregnant women).

Dynamics of the infant gut microbiota in the first 18 months of life: the impact of maternal HIV infection and breastfeeding

BACKGROUND

Access to antiretroviral therapy (ART) during pregnancy and breastfeeding for mothers with HIV has resulted in fewer children acquiring HIV peri- and postnatally, resulting in an increase in the number of children who are exposed to the virus but are not infected (HEU). HEU infants have an increased likelihood of childhood infections and adverse growth outcomes, as well as increased mortality compared to their HIV-unexposed (HUU) peers. We explored potential differences in the gut microbiota in a cohort of 272 Nigerian infants born to HIV-positive and negative mothers in this study during the first 18 months of life.

RESULTS

The taxonomic composition of the maternal vaginal and gut microbiota showed no significant differences based on HIV status, and the composition of the infant gut microbiota at birth was similar between HUU and HEU. Longitudinal taxonomic composition of the infant gut microbiota and weight-for-age z-scores (WAZ) differed depending on access to breast milk. HEU infants displayed overall lower WAZ than HUU infants at all time points. We observed a significantly lower relative abundance of Bifidobacterium in HEU infants at 6 months postpartum. Breast milk composition also differed by time point and HIV infection status. The antiretroviral therapy drugs, lamivudine and nevirapine, as well as kynurenine, were significantly more abundant in the breast milk of mothers with HIV. Levels of tiglyl carnitine (C5) were significantly lower in the breast milk of mothers without HIV. ART drugs in the breast milk of mothers with HIV were associated with a lower relative abundance of Bifidobacterium longum.

CONCLUSIONS

Maternal HIV infection was associated with adverse growth outcomes of HEU infants in this study, and these differences persist from birth through at least 18 months, which is a critical window for the development of the immune and central nervous systems. We observed that the relative abundance of Bifidobacterium spp. was significantly lower in the gut microbiota of all HEU infants over the first 6 months postpartum, even if HEU infants were receiving breast milk. Breastfeeding was of benefit in our HEU infant cohort in the first weeks postpartum; however, ART drug metabolites in breast milk were associated with a lower abundance of Bifidobacterium. Video abstract.

Higher prevalence of stunting and poor growth outcomes in HIV-exposed uninfected than HIV-unexposed infants in Kenya

BACKGROUND

With the growing population of HIV-exposed uninfected (HEU) children globally, it is important to determine population-level growth differences between HEU and HIV-unexposed uninfected (HUU) children.

METHODS

We analyzed data from a population-level survey enrolling mother-infant pairs attending 6-week and 9-month immunizations in 140 clinics across Kenya. Weight-for-age (WAZ), length-for-age (LAZ), head circumference-for-age (HCAZ) z-scores and underweight (WAZ < -2), stunting (LAZ < -2), and microcephaly (HCAZ < -2), were compared between HEU and HUU. Correlates of growth faltering and poor growth were assessed using generalized Poisson and linear regression models.

RESULTS

Among 2457 infants, 456 (19%) were HEU. Among mothers living with HIV, 64% received antiretroviral therapy (ART) and 22% were on antiretroviral prophylaxis during pregnancy. At 9 months, 72% of HEU and 98% of HUU were breastfeeding. At 6 weeks, HEU had lower mean WAZ (-0.41 vs. -0.09; P < 0.001) and LAZ (-0.99 vs. -0.31; P = 0.001) than HUU. Stunting was higher in HEU than HUU at 6 weeks (34% vs. 18%, P < 0.001) and 9 months (20% vs. 10%, P < 0.001). In multivariable analyses, HEU had lower mean LAZ at 6 weeks (-0.67, 95% confidence interval [CI]: -1.07, -0.26) and 9 months (-0.57, 95% CI: -0.92, -0.21) and HEU had higher stunting prevalence (week-6 adjusted prevalence ratio [aPR]: 1.88, 95% CI: 1.35, 2.63; month-9 aPR: 2.10, 95% CI: 1.41, 3.13). HEU had lower mean head circumference (-0.49, 95% CI: -0.91, -0.07) and higher prevalence of microcephaly (aPR: 2.21, 95% CI: 1.11, 4.41) at 9 months.

CONCLUSION

Despite high maternal ART coverage, HEU had poorer growth than HUU in this large population-level comparison. Optimizing breastfeeding practices in HEU may be useful to improve growth.

Breastfeeding Outcomes and Associated Risks in HIV-Infected and HIV-Exposed Infants: A Systematic Review

Purpose: To critically appraise recent literature regarding breastfeeding outcomes and associated risks in HIV-infected (HI) and HIV-exposed (HE) infants, using the Preferred Reporting Items for Systematic review and Meta-Analysis Protocols (PRISMA-P) statement guidelines. Materials and Methods: Five electronic databases were systematically searched to obtain English publications from the last 10 years (2010-2020), pertaining to breastfeeding outcomes and associated risks of HI and HE infants and children. Gray literature sources were also included. Data were extracted according to various data items and were synthesized using thematic synthesis. Results: Of the initial 7,151 sources identified, 42 articles were eligible for final inclusion. The final selection included 19 cohort studies and 2 expert committee reports, classified as gray literature. The remaining 21 studies comprised case-control, cross-sectional, and randomized controlled trial studies. The following themes were identified: breastfeeding outcomes in HI and HE infants, risks for suboptimal breastfeeding, HI and HE infant growth and developmental outcomes, and barriers and facilitators to feeding decisions. Most studies highlighted HE infants' growth and developmental outcomes and did not directly interrogate breastfeeding outcomes. The most prevalent risks for suboptimal breastfeeding were maternal factors affecting decision making for breastfeeding. Conclusions: This systematic review adds to the evidence of breastfeeding in HIV-affected mother-infant dyads. Findings reiterated that exclusive breastfeeding has a positive outcome on growth and development of all infants irrespective of HIV status. The review highlighted a dearth of research on breastfeeding outcomes of HI and HE infants. Large-scale prospective comparative studies should profile breastfeeding and developmental outcomes of infants with HIV infection or exposure and antiretroviral treatment exposure to enable early identification and intervention for this vulnerable population in low-income settings.

Immunopathogenesis in HIV-associated pediatric tuberculosis

Tuberculosis (TB) is an increasing global emergency in human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) patients, in which host immunity is dysregulated and compromised. However, the pathogenesis and efficacy of therapeutic strategies in HIV-associated TB in developing infants are essentially lacking. Bacillus Calmette-Guerin vaccine, an attenuated live strain of Mycobacterium bovis, is not adequately effective, which confers partial protection against Mycobacterium tuberculosis (Mtb) in infants when administered at birth. However, pediatric HIV infection is most devastating in the disease progression of TB. It remains challenging whether early antiretroviral therapy (ART) could maintain immune development and function, and restore Mtb-specific immune function in HIV-associated TB in children. A better understanding of the immunopathogenesis in HIV-associated pediatric Mtb infection is essential to provide more effective interventions, reducing the risk of morbidity and mortality in HIV-associated Mtb infection in infants. IMPACT: Children living with HIV are more likely prone to opportunistic infection, predisposing high risk of TB diseases. HIV and Mtb coinfection in infants may synergistically accelerate disease progression. Early ART may probably induce immune reconstitution inflammatory syndrome and TB pathology in HIV/Mtb coinfected infants.

Increased infectious-cause hospitalization among infants who are HIV-exposed uninfected compared with HIV-unexposed

OBJECTIVES

Increased risk of morbidity and hospitalization has been observed in children who are HIV-exposed uninfected (HEU) compared with HIV-unexposed uninfected (HUU). Studies in the era of universal maternal antiretroviral treatment (ART) are limited.

DESIGN

Prospective cohort.

METHODS

We investigated hospitalization between 29 days and 12 months of life in a South African cohort of infants born between February 2017 and January 2019 (HEU = 455; HUU = 458). All mothers known with HIV during pregnancy received ART. We reviewed hospital records and classified and graded infectious diagnoses using a standardized tool. We examined factors associated with infectious-cause hospitalization using mixed-effects Poisson regression.

RESULTS

Infants HEU vs. HUU had higher all-cause and infectious-cause hospitalization (13 vs. 7%, P = 0.004 and 10 vs. 6%, P = 0.014, respectively). Infectious causes accounted for most hospitalizations (77%). More infants HEU were hospitalized with severe or very severe infections than those HUU (9 vs. 6%; P = 0.031). Mortality (<1%) did not differ between groups. HIV exposure was a significant risk factor for infectious-cause hospitalization [adjusted incidence rate ratios (aIRRs) = 2.8; 95% confidence interval (CI) 1.5-5.4]. Although increased incidence of preterm birth (14 vs. 10%; P < 0.05) and shorter duration of breastfeeding (44 vs. 68% breastfed for ≥3 months, P < 0.001) among infants HEU vs. HUU contributed to increased hospitalization, they did not account for all the increased risk.

CONCLUSION

Infectious-cause hospitalization incidence was higher among infants HEU vs. HUU, likely partly because of higher incidence of preterm birth and lower breastfeeding rates among infants HEU. The increased infectious disease burden in HEU infants has important implications for health services in sub-Saharan Africa.

Neurological development of children who are HIV-exposed and uninfected

Widespread use of antiretroviral drugs for pregnant/breastfeeding females with human immunodeficiency virus (HIV) has led to declining vertical transmission. Despite being HIV-uninfected, the increasing number of children who are HIV-exposed and uninfected (CHEU) often present with developmental alterations. We review seminal and recent evidence on the neurological development of CHEU and associations with early life HIV/antiretroviral exposure. Our conceptual model highlights the numerous exposures and universal risk factors for CHEU developmental disorders. Early studies suggest a significant association between HIV exposure and neurological abnormalities, varying according to the burden of HIV-specific exposures and other risk factors. More recent observations from the modern era are inconsistent, although some studies suggest specific antiretrovirals may adversely affect neurological development of CHEU. As the CHEU population continues to grow, alongside simultaneous increases in types and combinations of antiretrovirals used in pregnancy, long-term monitoring of CHEU is necessary for understanding the effects of HIV/antiretroviral exposure on CHEU developmental outcomes. What this paper adds Evidence on the neurological development of children who are human immunodeficiency virus (HIV)-exposed and uninfected (CHEU) is synthesized. Comparisons are made to children who are HIV-unexposed, across treatment eras and settings, and by antiretroviral drug regimens and drug classes. CHEU exposures are complex and include HIV-specific and universal risk factors which may affect development during the early years of life.

Impaired T helper cell responses in human immunodeficiency virus-exposed uninfected newborns

Introduction

HIV‐exposed uninfected (HEU) newborns suffer from higher risks of opportunistic infections during the first months of life compared to HIV‐unexposed uninfected (HUU) newborns. Alterations in thymic mass, amounts of T helper (Th) cells, T‐cell receptor diversity, and activation markers have been found in HEU newborns, suggesting alterations in T cell ontogeny and differentiation. However, little is known about the ability of these cells to produce specialized Th responses from CD4⁺ T cells.

Method

To characterize the Th cell profile, we evaluated the frequency of Th₁ (CD183⁺CD194⁻CD196⁻/CXCR3⁺CCR4⁻CCR6⁻), Th₂ (CD183⁻CD194⁺CD196⁻/CXCR3⁻CCR4⁺CCR6⁻), Th₁₇ (CD183⁻CD194⁺CD196⁺/CXCR3⁻CCR4⁺CCR6⁺), and CD4⁺CD25⁺⁺ blood T‐cell phenotypes in 50 HEU and 25 HUU newborns. Early activation markers on CD4⁺ T cells and the Th cytokine profile produced from mononuclear cells under polyclonal T cell stimulation were also studied. Additionally, we probed the ability of CD4⁺ T cells to differentiate into interferon (IFN)‐γ‐producing Th₁ CD4⁺ T cells in vitro.

Results

Lower percentages of differentiated Th₁, Th₂, Th_17, and CD4⁺CD25⁺⁺ T cells were found in blood from HEU newborns than in blood from HUU newborns. However, polyclonally stimulated Th cells showed a similar ability to express CD69 and CD279 but produced less secreted interleukin (IL)‐2 and IL‐4. Interestingly, under Th₁ differentiation conditions, the percentages of CD4⁺IFN‐γ⁺ T cells and soluble IFN‐γ were higher in HEU newborns than in HUU newborns.

Conclusion

HEU neonates are born with reduced proportions of differentiated Th₁/Th₂/Th₁₇ and CD4⁺CD25⁺⁺ T cells, but the intrinsic abilities of CD4⁺ T cells to acquire a Th₁ profile are not affected by the adverse maternal milieu during development.

Dried Blood Specimens as an Alternative Specimen for Immune Response Monitoring During HIV Infection: A Proof of Concept and Simple Method in a Pediatric Cohort

Programs to prevent mother-to-child HIV transmission do not reduce the number of infants exposed during pregnancy and breastfeeding. HIV-exposed but uninfected children (HEU) present higher risk of morbidity and mortality than HIV-unexposed and uninfected children (UU). In this line, the study of immune biomarkers in HIV could improve prediction of disease progression, allowing to diminish comorbidity risk. Dried blood specimens (DBS) are an alternative to serum for collecting and transporting samples in countries with limited infrastructure and especially interesting for groups such as pediatrics, where obtaining a high sample volume is challenging. This study explores the usefulness of DBS for immune profile monitoring in samples from 30 children under clinical follow-up in Kinshasa: 10 HIV-infected (HIV+), 10 HEU, and 10 UU. We have measured the gene expression levels of 12 immune and inflammatory markers (CD14, IL-6, TNFα, HVEM, B7.1, HIF-1α, Siglec-10, IRAK-M, CD163, B7H5, PD-L1, and Galectin-9) in DBS samples by reverse transcription of total RNA and RT-qPCR. Principal component analysis, Kruskal-Wallis test, and Mann-Whitney test were performed in order to study group differences. HIV+ children presented significantly higher levels of seven biomarkers (CD14, IL-6 HVEM, B7.1, Siglec-10, HIF-1α, and CD163) than the UU group. In HEU, we found seven biomarkers significantly elevated (CD14, IL-6, HVEM, B7.1, Siglec-10, HIF-1α, and IRAK-M) vs. UU. Six biomarkers (CD14, IL-6, HVEM, B7.1, Siglec-10, and HIF-1α) showed a significantly higher expression in both HIV+ and HEU vs. UU, with HVEM and CD14 being significantly overexpressed among HIV+ vs. HEU. Our data reveal the utility of DBS for immune response monitoring. Moreover, significant differences in specific biomarker expression across groups strongly suggest the effect of HIV infection and/or HIV exposure on these immune biomarkers' expressions.

Growth Faltering and Developmental Delay in HIV-Exposed Uninfected Ugandan Infants: A Prospective Cohort Study

BACKGROUND

HIV-exposed but uninfected (HEU) infants are at increased risk of impaired early linear growth and cognitive development. We examined associations between prenatal and postnatal growth and subsequent neurodevelopment in Ugandan HEU infants, hypothesizing that early insults may explain alterations in both somatic growth and brain development.

METHODS

We prospectively followed a cohort of HEU infants from birth to 18 months of age, and measured length/height, weight, head, and arm circumference longitudinally. The Malawi Development Assessment Tool (MDAT, 12 and 18 months) and the Color Object Association Test (18 months) were used for developmental assessments.

RESULTS

Among 170 HEU infants, the prevalence of low-birth weight and failure to thrive was 7.6% and 37%, respectively. HEU infants had MDAT scores that were similar to the reference population. The mean (SD) score on the Color Object Association Test was 5.5 (3.1) compared with 6.9 (5.3) in developmentally normal children. Developmental ability at age 18 months showed strong cross-sectional correlation with weight-for-age (ρ = 0.36, P < 0.0001), length/height-for-age (ρ = 0.41, P < 0.0001), head circumference-for-age (ρ = 0.26, P = 0.0011), and mid-upper arm circumference-for-age (ρ = 0.34, P = 0.0014). There was a statistically significant correlation between birth weight and MDAT z-score at 18 months (ρ = 0.20, P = 0.010). Failure to thrive was associated with lower MDAT z-score [median -0.13 (IQR -0.75 to +0.14) versus +0.14 (IQR -0.44 to +0.63), P = 0.042].

CONCLUSION

Growth faltering in HEU infants was associated with lower attainment of developmental milestones at age 18 months. Our findings point to a simple screening method for identifying HEU infants at risk for developmental intervention.

Preterm birth and severe morbidity in hospitalized neonates who are HIV exposed and uninfected compared with HIV unexposed

OBJECTIVES

Infants who are HIV exposed but uninfected (HEU) compared with HIV unexposed uninfected (HUU) have an increased risk of adverse birth outcomes, morbidity and hospitalization. In the era of universal maternal antiretroviral treatment, there are few insights into patterns of neonatal morbidity specifically.

DESIGN

A prospective cohort study.

METHODS

We compared neonatal hospitalizations among infants who were HEU (n = 463) vs. HUU (n = 466) born between 2017 and 2019 to a cohort of pregnant women from a large antenatal clinic in South Africa. We examined maternal and infant factors associated with hospitalization using logistic regression.

RESULTS

Hospitalization rates were similar between neonates who were HEU and HUU (13 vs. 16%; P = 0.25). Overall, most hospitalizations occurred directly after birth (87%); infection-related causes were identified in 34%. The most common reason for hospitalization unrelated to infection was respiratory distress (25%). Very preterm birth (<32 weeks) (29 vs. 11%; P = 0.01) as well as very low birthweight (<1500 g) (34 vs. 16%; P = 0.02) occurred more frequently among hospitalized neonates who were HEU. Of those hospitalized, risk of intensive care unit (ICU) admission was higher in neonates who were HEU (53%) than HUU (27%) [risk ratio = 2.1; 95% confidence interval (95% CI) 1.3-3.3]. Adjusted for very preterm birth, the risk of ICU admission remained higher among neonates who were HEU (aRR = 1.8; 95% CI 1.1-2.9).

CONCLUSION

Neonates who were HEU (vs. HUU) did not have increased all-cause or infection-related hospitalization. However, very preterm birth, very low birthweight and ICU admission were more likely in hospitalized neonates who were HEU, indicating increased severity of neonatal morbidity.

Placental decidual arteriopathy and vascular endothelial growth factor A (VEGF-A) expression among women with and without HIV

BACKGROUND

Women with HIV (WHIV) are at higher risk of adverse birth outcomes. Proposed mechanisms for the increased risk include placental arteriopathy (vasculopathy) and maternal vascular malperfusion (MVM) due to antiretroviral therapy (ART) and medical comorbidities. However, these features and their underlying pathophysiologic mechanisms have not been well characterized in WHIV.

METHODS

We performed gross and histologic examination and immunohistochemistry staining for vascular endothelial growth factor A (VEGF-A), a key angiogenic factor, on placentas from women with one or more MVM risk factors including: weight <5 th percentile, histologic infarct or distal villous hypoplasia, nevirapine-based ART, hypertension, and pre-eclampsia/eclampsia during pregnancy. We compared pathologic characteristics by maternal HIV serostatus.

RESULTS

A total of 27/41 (66%) placentas assessed for VEGF-A were from WHIV. Mean maternal age was 27 years. Among WHIV, median CD4 T-cell count was 440 cells/mm 3 and HIV viral load was undetectable in 74%. Of VEGF-A stained placentas, both decidua and villous endothelium tissue layers were present in 36 (88%). VEGF-A was detected in 31/36 (86%) with decidua present, and 39/40 (98%) with villous endothelium present. There were no differences in VEGF-A presence in any tissue type by maternal HIV serostatus (P=0.28-1.0). MVM was more common in placentas selected for VEGF-A staining (51 versus 8%, P<0.001).

CONCLUSIONS

VEGF-A immunostaining was highly prevalent, and staining pattern did not differ by maternal HIV serostatus among those with MVM risk factors, indicating the role of VEGF-A in placental vasculopathy may not differ by maternal HIV serostatus.

Brief Report: Chronic Placental Inflammation Among Women Living With HIV in Uganda

BACKGROUND

HIV-exposed, uninfected (HEU) children have poorer early-life outcomes than HIV-unexposed children. The determinants of adverse health outcomes among HEU children are poorly understood but may result from chronic placental inflammation (CPI).

SETTING AND METHODS

We enrolled 176 pregnant women living with HIV (WLWH) taking antiretroviral therapy in southwestern Uganda and 176 HIV-uninfected women to compare CPI prevalence by maternal HIV serostatus. Placentas were evaluated histologically by an expert pathologist for presence of CPI, defined as chronic chorioamnionitis, plasma cell deciduitis, villitis of unknown etiology, or chronic histiocytic intervillositis. Placentas with CPI were additionally immunostained with CD3 (T cell), CD20 (B cell), and CD68 (macrophage) markers to characterize inflammatory cell profiles.

RESULTS

WLWH and HIV-uninfected women had similar age, parity, and gestational age. Among WLWH, the mean CD4 count was 480 cells/µL, and 74% had an undetectable HIV viral load. We detected CPI in 16 (9%) placentas from WLWH and 24 (14%) from HIV-uninfected women (P = 0.18). Among WLWH, CPI was not associated with the CD4 count or HIV viral load. Villitis of unknown etiology was twice as common among HIV-uninfected women than WLWH (10 vs. 5%, P = 0.04). Among placentas with CPI, more villous inflammatory cells stained for CD3 or CD68 among HIV-uninfected women than WLWH (79% vs. 46%, P = 0.07).

CONCLUSIONS

CPI prevalence did not differ by HIV serostatus. T-cell (CD3) and macrophage (CD68) markers were more prevalent in placental inflammatory cells from HIV-uninfected women. Our results do not support CPI as a leading mechanism for poor outcomes among HEU children in the antiretroviral therapy era.

Growth Trajectories of HIV Exposed and HIV Unexposed Infants. A Prospective Study in Gweru, Zimbabwe

Background

With the increasing HIV seroprevalence among women of childbearing age in sub-Saharan Africa, limited data on growth outcomes of HIV exposed infants under current policies of universal maternal antiretroviral therapy exist.

Methods

The longitudinal growth patterns of 114 HIV exposed and unexposed infants were assessed and compared. The prevalence and factors associated with malnutrition were established. Infants under prevention of mother to child transmission care were recruited at 6 weeks post-delivery as were their HIV unexposed counterparts. Weight and length measurements were recorded at birth, 6 and 16 weeks postpartum.

Results

HIV vertical transmission rate was 8.8%. HIV exposed infants had significantly lower mean birth weights compared to HIV unexposed infants (2.9 ± 0.3; 3.2 ± 0.5; P < .001) respectively. Mean weight/length-for-age z-scores for HIV exposed, uninfected (HEU) infants were significantly below those of the HIV unexposed infants during follow up. By 6 weeks of age, 28.5% of HEU infants were malnourished while no malnutrition was evident in HIV unexposed infants. A gestational age <37 weeks (OR: 3.83; 95% CI: 1.03-14.30; P = .045) and HIV exposure (OR: 1.62; 95% CI: 0.17-15.73; P = .017) substantially increased the risk of stunting.

Conclusion

Growth deficits were witnessed in HIV exposed infants compared to HIV unexposed infants. There is need for early nutritional monitoring and support among HIV exposed infants.

Mortality, Human Immunodeficiency Virus (HIV) Transmission, and Growth in Children Exposed to HIV in Rural Zimbabwe

BACKGROUND

Clinical outcomes of children who are human immunodeficiency virus (HIV)-exposed in sub-Saharan Africa remain uncertain.

METHODS

The Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial evaluated improved infant and young child feeding (IYCF) and/or improved water, sanitation, and hygiene in 2 rural Zimbabwean districts with 15% antenatal HIV prevalence and > 80% prevention of mother-to-child transmission (PMTCT) coverage. Children born between February 2013 and December 2015 had longitudinal HIV testing and anthropometry. We compared mortality and growth between children who were HIV-exposed and HIV-unexposed through 18 months. Children receiving IYCF were excluded from growth analyses.

RESULTS

Fifty-one of 738 (7%) children who were HIV-exposed and 198 of 3989 (5%) children who were HIV-unexposed (CHU) died (hazard ratio, 1.41 [95% confidence interval {CI}, 1.02-1.93]). Twenty-five (3%) children who were HIV-exposed tested HIV positive, 596 (81%) were HIV-exposed uninfected (CHEU), and 117 (16%) had unknown HIV status by 18 months; overall transmission estimates were 4.3%-7.7%. Mean length-for-age z score at 18 months was 0.38 (95% CI, .24-.51) standard deviations lower among CHEU compared to CHU. Among 367 children exposed to HIV in non-IYCF arms, 147 (40%) were alive, HIV-free, and nonstunted at 18 months, compared to 1169 of 1956 (60%) CHU (absolute difference, 20% [95% CI, 15%-26%]).

CONCLUSIONS

In rural Zimbabwe, mortality remains 40% higher among children exposed to HIV, vertical transmission exceeds elimination targets, and half of CHEU are stunted. We propose the composite outcome of "alive, HIV free, and thriving" as the long-term goal of PMTCT programs.

CLINICAL TRIALS REGISTRATION

NCT01824940.

Inflammation, cytomegalovirus and the growth hormone axis in HIV-exposed uninfected Zimbabwean infants

OBJECTIVES

Despite avoiding HIV infection, HIV-exposed uninfected (HEU) infants have poorer clinical outcomes than HIV-unexposed infants, including impaired growth. The growth hormone (GH) axis is an important regulator of infant growth through hepatic synthesis of insulin-like growth-factor-1 (IGF-1), and may be disrupted by chronic inflammation and acute infections, including cytomegalovirus (CMV). We tested the hypothesis that these factors lead to disruption of the GH axis in HEU infants, which might contribute to their impaired growth.

DESIGN

Substudy of 343 infants from the ZVITAMBO trial in Harare, Zimbabwe.

METHODS

IGF-1, growth parameters, C-reactive protein (CRP) and CMV viraemia were evaluated in 243 HEU infants and 100 HIV-unexposed infants. Univariable linear and logistic regression models were used to determine associations between IGF-1 and growth parameters, CRP and CMV.

RESULTS

Mean 6-week IGF-1 was significantly lower in HEU compared with HIV-unexposed infants (29.6 vs. 32.6 ng/ml; P = 0.014), and associated with subsequent linear and ponderal growth through 6 months of age. CRP was inversely correlated with IGF-1 in all infants regardless of HIV exposure status (β = -0.84; P = 0.03). CMV viral loads were inversely correlated with IGF-1 in HEU (β = -1.16; P = 0.008) but not HIV-unexposed (β = 0.21; P = 0.83) infants.

CONCLUSION

Overall, we found evidence for greater disruption of the GH axis in HEU compared with HIV-unexposed infants as early as 6 weeks of age, suggesting a role for reduced IGF-1 in mediating growth impairment in HEU infants. Inflammation and coinfections may be drivers of growth impairment in HEU infants by disrupting the GH axis.

The University of Zimbabwe College of Health Sciences (UZ-CHS) BIRTH COHORT study: rationale, design and methods

BACKGROUND

Commencing lifelong antiretroviral therapy (ART) immediately following HIV diagnosis (Option B+), has greatly improved maternal-infant health. Thus, large and increasing numbers of HIV-infected women are on ART during pregnancy, a situation concurrently increasing numbers of HIV-exposed-uninfected (HEU) infants. Compared to their HIV-unexposed-uninfected (HUU) counterparts, HEU infants show higher rates of adverse birth outcomes, mortality, infectious/non-communicable diseases including impaired growth and neurocognitive development. There is an urgent need to understand the impact of HIV and early life ART exposures, immune-metabolic dysregulation, comorbidities and environmental confounders on adverse paediatric outcomes.

METHODS

Six hundred (600) HIV-infected and 600 HIV-uninfected pregnant women ≥20 weeks of gestation will be enrolled from four primary health centres in high density residential areas of Harare. Participants will be followed up as mother-infant-pairs at delivery, week(s) 1, 6, 10, 14, 24, 36, 48, 72 and 96 after birth. Clinical, socio-economic, nutritional and environmental data will be assessed for adverse birth outcomes, impaired growth, immune/neurodevelopment, vertical transmission of HIV, hepatitis-B/C viruses, cytomegalovirus and syphilis. Maternal urine, stool, plasma, cord blood, amniotic fluid, placenta and milk including infant plasma, dried blood spot and stool will be collected at enrolment and follow-up visits. The composite primary endpoint is stillbirth and infant mortality within the first two years of life in HEU versus HUU infants. Maternal mortality in HIV-infected versus -uninfected women is another primary outcome. Secondary endpoints include a range of maternal and infant outcomes. Sub-studies will address maternal stress and malnutrition, maternal-infant latent tuberculosis, Helicobacter pylori infections, immune-metabolomic dysregulation including gut, breast milk and amniotic fluid dysbiosis.

DISCUSSION

The University of Zimbabwe-College of Health-Sciences-Birth-Cohort study will provide a comprehensive assessment of risk factors and biomarkers for HEU infants' adverse outcomes. This will ultimately help developing strategies to mitigate effects of maternal HIV, early-life ART exposures and comorbidities on infants' mortality and morbidity.

TRIAL REGISTRATION

ClinicalTrial.gov Identifier: NCT04087239 . Registered 12 September 2019.

Umbilical cord interleukin-6 predicts outcome in very low birthweight infants in a high HIV-burden setting: a prospective cohort study

OBJECTIVES

South Africa has a double burden of high neonatal mortality and maternal HIV prevalence. Common to both is a proinflammatory in utero and perinatal milieu. The aim of this study was to determine cytokine profiles in HIV exposed (HE) and HIV unexposed (HU) very low birthweight (VLBW) infants and to determine whether these were associated with predischarge outcomes.

DESIGN

Single-centre, prospective cohort study conducted from 1 June 2017 to 31 January 2019.

PATIENTS

Inborn infants with birth weight of <1500 g were enrolled and cord blood was collected for interleukin (IL)-6 and tumour necrosis factor alpha (TNF-α) assays. Participants provided informed consent and ethics approval was obtained.

OUTCOME MEASURES

The primary outcome was umbilical cord cytokine levels according to maternal HIV status. Secondary outcomes included death and/or serious neonatal infection, necrotising enterocolitis, intraventricular haemorrhage, periventricular leucomalacia, chronic lung disease and haemodynamically significant patent ductus arteriosus before discharge.

RESULTS

A total of 279 cases were included with 269 cytokine assays performed on 122 HEs and 147 HUs. Median IL-6 levels were 53.0 pg/mL in HEs and 21.0 pg/mL in HUs (p=0.07). Median TNF-α levels were 7.2 pg/mL in HEs and 6.5 pg/mL in HUs (p=0.6). There was significantly more late-onset sepsis in the HE group compared with the HU group (41.2% vs 27.9%) (p=0.03). IL-6 levels were significantly higher for those with any adverse outcome (p=0.006) and death and/or any adverse outcome (p=0.0001). TNF-α levels did not differ according to predischarge outcomes.

CONCLUSION

There is no significant difference in IL-6 and TNF-α levels in cord blood of HE compared with HU VLBWs. However, IL-6 levels are significantly higher in VLBWs with adverse predischarge outcomes, and VLBW HEs are at increased risk of adverse predischarge outcomes compared with HUs, particularly late-onset sepsis.

Differences in Growth of HIV-exposed Uninfected Infants in Ethiopia According to Timing of In-utero Antiretroviral Therapy Exposure

BACKGROUND

There are concerns about the adverse effect of in-utero exposure to antiretroviral therapy (ART) on the growth of HIV exposed-uninfected (HEU) infants. We compared growth of HEU-infants according to the timing and type of ART exposure.

METHODS

A retrospective cohort study was conducted by abstracting clinical data from HIV-infected mothers and HEU-infants in Addis Ababa, Ethiopia between February 2013 and October 2016. Mixed-effects linear models were used to compare changes in weight and length and cox proportional hazard models were used to evaluate stunting (length-for-age z score <-2.0) and underweight (weight-for-age z score <-2.0).

RESULTS

A total of 624 HEU-infants were included in the analyses. Infants exposed to ART from conception had a lower rate of change in length [β = -0.54, 95% confidence interval (CI): -1.00 to -0.08] the first 3 months of life, as compared with infants exposed from late pregnancy. Risk of stunting was 51.9 per 100 person-years and risk of underweight was 26.7 per 100 person-years. Exposure to ART from conception was associated with a higher rate of stunting as compared with exposure from late pregnancy (adjusted hazard ratio = 1.95, 95% CI: 1.27-2.99). Infants born to mothers with advanced disease had a higher incidence of underweight compared with infants born to mothers with early-stage disease adjusted hazard ratio = 1.99, 95% CI: 1.32-3.03).

CONCLUSIONS

In HEU-infants, exposure to ART from conception was associated with decrease growth during early infancy and higher incidence of stunting compared with treatment exposure later in pregnancy. Close monitoring of HEU-infants' growth and prompt nutritional intervention is essential.

Examining the relationship between diarrhea and linear growth in Kenyan HIV-exposed, uninfected infants

BACKGROUND

Diarrhea in infancy can compromise linear growth and this relationship is likely influenced by diarrhea severity, number of episodes, and the timing of those episodes. HIV exposed, uninfected infants (HEU) have higher risk of growth faltering, infectious morbidity and mortality than HIV-unexposed infants and may be representative of children particularly vulnerable to diarrhea-associated linear growth faltering.

METHODOLOGY/PRINCIPAL FINDINGS

We utilized data from a cohort of Kenyan HEU infants followed from birth to 12 months of age. Infant length and morbidity were ascertained at monthly study visits and sick visits. Longitudinal models estimated the association between diarrhea severity and length-for-age Z-score (LAZ) in the following month, at 12 months of age, and in 6-month intervals. The 372 enrolled infants experienced an average of 2.15 episodes (range: 0-8) of diarrhea and 0.54 episodes (0-4) of moderate-to-severe diarrhea (MSD) between birth and 12 months. Surviving infants had a mean LAZ of -0.97 (standard deviation: 1.2) at 12 months. MSD was significantly associated with an average loss of 0.14 (95% Confidence Interval [CI]: -0.24, -0.05, p = 0.003) in LAZ one month after the episode. Linear growth outcomes were not predicted by cumulative episodes of diarrhea, or timing of diarrhea during infancy.

CONCLUSIONS/SIGNIFICANCE

Diarrhea severity influenced the relationship between diarrhea and subsequent linear growth. HEU infants with MSD may benefit from nutritional interventions following severe diarrhea to protect against linear growth faltering.

Escherichia coli Antimicrobial Susceptibility Reduction amongst HIV-Infected Individuals at the University Teaching Hospital, Lusaka, Zambia

Increased antimicrobial resistance among Human Immunodeficiency Virus (HIV)-infected individuals to commonly used antibiotics in the treatment of gastroenteritis is a public health concern, especially in resource-limited settings. We set out to compare the antimicrobial susceptibility pattern of Escherichia coli (E. coli) isolates from HIV-infected and HIV-uninfected individuals at a tertiary hospital in Lusaka, Zambia. An analytical cross-sectional study was conducted at the University Teaching Hospital from May 2019 to August 2019. Stool samples were screened, and 79 HIV-infected individuals matched by age and sex with 84 HIV-uninfected individuals that presented with E. coli associated gastroenteritis were studied. Demographics were collected from the Laboratory Information System (LIS) and stool samples were collected in a sterile leak-proof container. Samples were cultured and only those where E. coli was isolated were included in the study and tested for antimicrobial susceptibility by the Kirby-Bauer disk diffusion technique. HIV-positive individuals were 3 times (adjusted odds ratio (AOR) = 3.17; 95% CI (1.51, 6.66); p < 0.001) more likely to be resistant to quinolones compared with their HIV-negative counterparts. Similarly, HIV-positive individuals were almost 4 times (AOR = 3.97, 95% CI (1.37, 11.46); p = 0.011) more likely to have multidrug-resistant E. coli compared with those who were HIV-negative. HIV infection was associated with reduced E. coli susceptibility to commonly used antibiotics, and most cases showed resistance.

Growth and Neurodevelopment of HIV-Exposed Uninfected Children: a Conceptual Framework

Purpose of Review

The population of HIV-exposed uninfected (HEU) children is expanding rapidly, and over one million HEU infants are born each year globally. Several recent studies have reported that HEU children, particularly in low- and middle-income countries, are at risk of poor outcomes, including impaired growth and neurodevelopment. However, the reasons for poor clinical outcomes amongst HEU children remain unclear.

Recent Findings

We summarise the findings from recent large studies that have characterised growth and neurodevelopment in HEU children, identified risk factors and explored underlying mechanistic pathways. We propose a conceptual framework to explain how exposure to HIV and antiretroviral therapy (ART) may lead to adverse growth and neurodevelopment in uninfected children, and review the available evidence and research gaps.

Summary

We propose that HEU children are affected both indirectly, through the augmentation of universal risk factors underlying poor growth and neurodevelopment, and directly through HIV/ART-specific pathways, which ultimately may converge through a series of common pathogenic mechanisms. In the era of universal ART, a better understanding of these pathways is crucial to inform future prevention and intervention strategies.

Current trends and new developments in HIV research and periodontal diseases

With the advent of combined antiretroviral therapies, the face of HIV infection has changed dramatically from a disease with almost certain mortality from serious comorbidities, to a manageable chronic condition with an extended lifespan. In this paper we present the more recent investigations into the epidemiology, microbiology, and pathogenesis of periodontal diseases in patients with HIV, and the effects of combined antiretroviral therapies on the incidence and progression of these diseases both in adults and perinatally infected children. In addition, comparisons and potential interactions between the HIV-associated microbiome, host responses, and pathogenesis in the oral cavity with the gastrointestinal tract and other areas of the body are presented. Also, the effects of HIV and combined antiretroviral therapies on comorbidities such as hyposalivation, dementia, and osteoporosis on periodontal disease progression are discussed.

Maternal and child health outcomes in rural South African mothers living with and without HIV

In the era of widespread antiretroviral therapy (ART), consequences of being HIV-exposed is unclear for children, especially in rural communities. A population sample of consecutive births (470/493) in the Eastern Cape of South Africa (SA) were recruited and reassessed at five points over the first 24 months. Maternal and child outcomes between mothers living with and without HIV were assessed using multiple linear and logistic regressions. At birth, 28% of the sample was mothers living with HIV and five additional mothers seroconverted. All mothers living with HIV reported taking ART. The rate of depressed mood and IPV was similar across serostatus. However, mothers living with HIV significantly decreased their alcohol use after learning about their pregnancy and were more likely to exclusively breastfeed when compared to mothers without HIV. Despite maternal HIV status, children had similar growth across the first 24 months of life. Future work is needed to assess if these developmental trajectories will persist.

Caries experience and oral health related quality of life in a cohort of Ugandan HIV-1 exposed uninfected children compared with a matched cohort of HIV unexposed uninfected children

Background

Very few studies consider the oral health status and quality of life in HIV-1 exposed uninfected (HEU) children. The aim of this study was to estimate the prevalence of caries in primary teeth and its oral health related quality of life impacts in HEU children compared to HIV-unexposed-uninfected (HUU) children, whilst adjusting for confounding covariates.

Methods

This study uses data from the Ugandan site of the ANRS 121741 PROMISE- PEP trial (ClinicalTrials.gov, number NCT00640263) conducted in 2009–2013 that recruited mothers with HIV-1 and their uninfected children. Of 244 HEU-children-caretaker pairs available at the end of the one-year trial, 166 were re-enrolled in the ANRS 12341 PROMISE-PEP M&S study at 5–7 years and 164 were included in this study. These were age and sex-matched with 181 HUU children-caretaker comparators. Caries experience was recorded using World Health Organization’s Decayed, Missed and Filled teeth (dmft/DMFT) indices. The Early Childhood Oral health Impact Scale (ECOHIS) was used for assessment of oral health related quality of life. Mixed effects logistic regression was conducted with dmft and ECOHIS scores as outcomes and HIV-1 exposure status as the main exposure.

Results

Forty-eight percent of HEU children and 60% of HUU had dmft> 0. Corresponding figures for ECOHIS> 0 were 12% of HEU and 22% of HUU. The crude analysis showed differences related to HIV-1 exposure in caries experience and oral health related quality of life. Mixed effect logistic regression analyses were not significant when adjusted for use of dental care and toothache. If caregivers’ DMFT> 0, the adjusted odds ratio for caries experience (dmft> 0) was 1.6 (95% CI: 1.0–2.8) while if dmft> 0 the adjusted odds ratio for quality of life impacts (ECOHIS> 0) was 4.6 (95% CI: 2.0–10.6).

Conclusion

The prevalence of untreated caries in primary teeth and quality of life impacts was high in this study population. HIV-1 exposed uninfected children were not more likely than HUU children to experience dental caries or have impaired oral health related quality of life. Given the global expansion of the HEU child population, the present findings indicating no adverse effect of pre- and post-natal HIV-1 exposure on caries in deciduous teeth are reassuring.

Association of maternal HIV-1 severity with dental caries: an observational study of uninfected 5- to 7-yr-old children of HIV-1-infected mothers without severe immune suppression

Treatment programs to prevent perinatal and postnatal HIV-1 transmission have become available in sub-Saharan Africa, leading to an emerging population of HIV-1 exposed uninfected (HEU) children. Exposure to HIV-1 in utero and during breastfeeding may increase the risk of morbidity and mortality in HEU children. This study estimated the association of the severity of maternal HIV-1 infection as assessed by CD4 count and viral load at baseline (7 d postpartum), with  dmft count of their 5- to 7-yr-old HEU offspring. A follow-up study was conducted of HIV-1-infected mother-HEU children pairs (n = 164) from the Ugandan site of the ANRS 12341-PROMISE- PEP trial (ClinicalTrials.gov, number NCT00640263). HIV-1-infected mothers were interviewed and the HEU children were examined for caries using the World Health Organization's survey methods for field conditions and the dmft index. Directed acyclic graphs and negative binomial regression were used for analyses. The prevalence of 1 or more dmft was 48%. Negative binomial regression showed no association between the dmft count and maternal CD4 counts 7 d postpartum but a 10% lower dmft count with longer breastfeeding duration was found. Maternal CD4 count at birth was not associated with the dental caries experience in uninfected children born to women without severe immune suppression, while there appeared to be a protective effect of high viral load and breastfeeding duration.

Detectable HIV-RNA Viral Load Among HIV-Infected Pregnant Women on Treatment in Northern Uganda

BACKGROUND / OBJECTIVES

Detectable HIV viral load among HIV-infected pregnant women remains a public health threat. We aimed to determine factors associated with detectable viral load among HIV-infected pregnant women in Lira, Northern Uganda.

METHODS

We conducted a cross-sectional survey among 420 HIV-infected pregnant women attending Lira Regional Referral Hospital using a structured questionnaire and combined it with viral load tests from Uganda National Health Laboratories. We conducted multivariable logistic regression while adjusting for confounders to determine the factors associated with detectable viral load and we report adjusted odds ratios and proportion of women with viral load less than 50 copies/ml and above 1000 copies, respectively.

RESULTS

The prevalence of detectable viral load (>50 copies/ml) was 30.7% (95%CI: 26.3% - 35.4%) and >1000 copies/ml was 8.1% (95% CI: 5.7% - 11.1%). Factors associated with detectable viral load were not belonging to the Lango ethnicity (adjusted odds ratio = 1.92, 95%CI: 1.05 - 3.90) and taking a second-line (protease inhibitor-based) regimen (adjusted odds ratio = 4.41, 95%CI: 1.13 - 17.22).

CONCLUSIONS AND GLOBAL HEALTH IMPLICATIONS

HIV-infected pregnant women likely to have detectable viral load included those taking a protease inhibitor-based regimen and those who were not natives of Lira. We recommend intensified clinical and psychosocial monitoring for medication compliance among HIV-infected pregnant women that are likely to have a detectable viral load to significantly lower the risk of vertical transmission of HIV in Lira specifically those taking a protease inhibitor-based regimen and those who are non-natives to the study setting. Much as the third 90% of the global UNAIDS 90-90-90 target has been achieved, the national implementation of PMTCT guidelines should be tailored to its contextual needs.

Influence of maternal HIV infection on fetal thymus size

Objective To reveal the effect of a maternal human immunodeficiency virus (HIV) infection on the fetal thymus size. Methods The sonographic fetal thymus size was measured retrospectively in 105 pregnancies with maternal HIV infection and in 615 uncomplicated singleton pregnancies. The anteroposterior thymic and the intrathoracic mediastinal diameter were determined in the three-vessel view and their quotient, the thymic-thoracic ratio (TT ratio), was calculated. The study group was subdivided into three groups by the maternal viral load on the date of ultrasound (<50 cop./mL, 50-1000 cop./mL, >1000 cop./mL). Furthermore, an association between prognostic factors of the HIV infection such as the lymphocyte count, CD4/CD8 ratio, HIV medication and the thymus size, was investigated using correlation analyses. Results Fetal thymus size in pregnancies of HIV-positive mothers showed to be noticeably larger than in uncomplicated pregnancies. The mean TT ratio in the HIV-positive group was 0.389 and in the control group 0.345 (P < 0.001). There was no association between any maternal HIV parameter or medication and the size of the thymus gland. Conclusion Maternal HIV infection was associated with an increased fetal thymus size. Further consequences of intrauterine HIV exposure for fetal outcome and the development of the immune system of HIV-exposed uninfected (HEU) infants must be discussed.

Birth size and early pneumonia predict linear growth among HIV-exposed uninfected infants

Stunting remains a global health priority, particularly in sub-Saharan Africa. Identifying determinants of linear growth in HIV-exposed uninfected (HEU) infants can inform interventions to prevent stunting in this vulnerable population. HIV-infected mothers and their uninfected infants were followed monthly from pregnancy to 12-month post-partum in Nairobi, Kenya. Mixed-effects models estimated the change in length-for-age z-score (LAZ) from birth to 12 months by environmental, maternal, and infant characteristics. Multivariable models included factors univariately associated with LAZ. Among 372 HEU infants, mean LAZ decreased from -0.54 (95% confidence interval [CI] [-0.67, -0.41]) to -1.09 (95% CI [-1.23, -0.96]) between 0 and 12 months. Declines in LAZ were associated with crowding (≥2 persons per room; adjusted difference [AD] in 0-12 month change: -0.46; 95% CI [-0.87, -0.05]), use of a pit latrine versus a flush toilet (AD: -0.29; 95% CI [-0.57, -0.02]), and early infant pneumonia (AD: -1.14; 95% CI [-1.99, -0.29]). Infants with low birthweight (<2,500 g; AD: 1.08; 95% CI [0.40, 1.76]) and birth stunting (AD: 1.11; 95% CI [0.45, 1.78]) experienced improved linear growth. By 12 months of age, 46 infants were stunted, of whom 11 (24%) were stunted at birth. Of the 34 infants stunted at birth with an available 12-month LAZ, 68% were not stunted at 12 months. Some low birthweight and birth-stunted HEU infants had significant linear growth recovery. Early infant pneumonia and household environment predicted poor linear growth and may identify a subgroup of HEU infants for whom to provide growth-promoting interventions.

Unmasking the vulnerabilities of uninfected children exposed to HIV

Although programmes to reduce vertical transmission of HIV mean fewer children are acquiring HIV, more needs to be done to understand the longer term outcomes of exposure, say Vundli Ramokolo and colleagues

The impact of in utero HIV exposure on gut microbiota, inflammation, and microbial translocation

HIV-exposed but uninfected (HEU) children represent a growing population and show a significantly higher number of infectious diseases, several immune alterations, compromised growth, and increased mortality rates when compared to HIV-unexposed children. Considering the impact that the gut microbiota has on general host homeostasis and immune system development and modulation, we hypothesized that HEU children present altered gut microbiota that is linked to the increased morbidity and the immune system disorders faced by them. Our experiments revealed no differences in beta and alpha diversity of the gut microbiota between HEU and unexposed children or between HIV-infected and uninfected mothers. However, there were differences in the abundance of several taxa from the gut microbiota between HEU and unexposed children and between HIV-infected and uninfected mothers. Functional prediction based on 16S rRNA sequences also indicated differences between HEU and unexposed children and between infected and uninfected mothers. In addition, we detected no differences between HEU and unexposed children in relation to weight, weight-for-age z scores, albumin serum levels, or microbial translocation and inflammation markers. In summary, HIV-infected mothers and their HIV-exposed children present alterations in the abundance of several taxa in the gut microbiome and the predicted functional metagenome when compared to uninfected mothers and unexposed children. Knowledge about the gut microbiome of HEU children in different settings is essential in order to determine better treatments for this susceptible population.

Feeding difficulties in infants with unrepaired cleft lip and palate and HIV-exposure

BACKGROUND

There is limited description of the feeding characteristics of infants with unrepaired cleft lip and palate, exposed to HIV, but not necessarily infected.

OBJECTIVE

To compare the feeding characteristics of infants with unrepaired cleft lip and palate and HIV-exposure, to infants with unrepaired cleft lip and palate only.

METHOD

A two-group comparative design with a validated measure, the Neonatal Feeding Assessment Scale was used. The effectiveness of oral feeding skills were included as objective measure. Twelve participants with unrepaired cleft lip and palate and HIV-exposure and 13 with unrepaired cleft lip and palate were matched according to cleft type and use of feeding obturator. There were no differences between the groups for mean age, birth weight and gestation. Participants were between two and 89 days old, bottle fed, and had no syndrome/co-occurring disorder.

RESULTS

Nine (75%) participants in the research group and only two (15.38%) in the control grouppresented with the likelihood of oropharyngeal dysphagia. Apart from feeding difficulties as a result of structural impairment, the research group showed symptoms of neurological involvement.

CONCLUSION

The research group presented with distinctive symptoms of oropharyngeal dysphagia. More studies using different measuring tools are required to strengthen the evidence.

Safety and Immunogenicity of Measles Vaccination in HIV-Infected and HIV-Exposed Uninfected Children: A Systematic Review and Meta-Analysis

BACKGROUND

HIV-infected and HIV-exposed uninfected (HEU) children have an increased risk of measles that may be due to altered immune responses or suboptimal timing of measles vaccination. We aimed to evaluate the safety and immunogenicity of measles vaccination in HIV-infected and HEU children.

METHODS

For this systematic review and meta-analysis, we searched PubMed, Embase, Cochrane Library, CINAHL, Global Health Library and IndMED on May 9, 2018. Studies were included if they reported on safety or seroresponse (either seroprotection/seropositivity/seroconversion) after measles vaccination in HIV-infected or HEU children. We calculated pooled estimates to compare immunogenicity outcomes between HIV-infected, HEU and HIV-unexposed children, using risk ratios [RRs] (with 95%CIs). PROSPERO registration number: CRD42017057411.

FINDINGS

Seventy-one studies met the inclusion criteria (15,363 children). Twenty-eight studies reported on safety; vaccine-associated adverse events and deaths were uncommon. Sixty-two studies reported on immunogenicity, 27 were included in the meta-analysis. HIV-infected children had lower seroresponse rates after primary vaccination compared with HIV-unexposed (RR 0.74; 95%CI: 0.61-0.90, I 2  = 85.9%) and HEU children (0.78; 0.69-0.88, I 2  = 77.1%), which was mitigated by antiretroviral therapy and time interval between vaccination and serology. HEU and HIV-unexposed children had similar seroresponses. Vaccination at 6-months resulted in similar proportions of HIV-infected children having seroresponse compared with HIV-unexposed (0.96; 0.77-1.19) and HEU children (1.00; 0.73-1.37, I 2  = 63.7%).

INTERPRETATION

Primary measles vaccination at 6-months of age may provide protection against measles during early infancy in settings with high prevalence of maternal HIV-infection, however, further studies are needed to evaluate this strategy in HEU children and HIV-infected children receiving antiretroviral therapy.

FUNDING

South African Research Chairs Initiative of the Department of Science and Technology and National Research Foundation in Vaccine Preventable Diseases; Medical Research Council: Respiratory and Meningeal Pathogens Research Unit.

Oral microbiota in youth with perinatally acquired HIV infection

BACKGROUND

Microbially mediated oral diseases can signal underlying HIV/AIDS progression in HIV-infected adults. The role of the oral microbiota in HIV-infected youth is not known. The Adolescent Master Protocol of the Pediatric HIV/AIDS Cohort Study is a longitudinal study of perinatally HIV-infected (PHIV) and HIV-exposed, uninfected (PHEU) youth. We compared oral microbiome levels and associations with caries or periodontitis in 154 PHIV and 100 PHEU youth.

RESULTS

Species richness and alpha diversity differed little between PHIV and PHEU youth. Group differences in average counts met the significance threshold for six taxa; two Corynebacterium species were lower in PHIV and met thresholds for noteworthiness. Several known periodontitis-associated organisms (Prevotella nigrescens, Tannerella forsythia, Aggregatibacter actinomycetemcomitans, and Filifactor alocis) exhibited expected associations with periodontitis in PHEU youth, associations not observed in PHIV youth. In both groups, odds of caries increased with counts of taxa in four genera, Streptococcus, Scardovia, Bifidobacterium, and Lactobacillus.

CONCLUSIONS

The microbiomes of PHIV and PHEU youth were similar, although PHIV youth seemed to have fewer "health"-associated taxa such as Corynebacterium species. These results are consistent with the hypothesis that HIV infection, or its treatment, may contribute to oral dysbiosis.

Altered Toll-Like Receptor-4 Response to Lipopolysaccharides in Infants Exposed to HIV-1 and Its Preventive Therapy

Pathogen sensing and recognition through pattern recognition receptors, and subsequent production of pro-inflammatory cytokines, is the cornerstone of the innate immune system. Despite the fact that HIV-exposed uninfected (HEU) infants are prone to serious bacterial infections, no study has focused on the functionality of their bacteria recognition system. This is the first study to investigate baseline levels of three critically important immune response molecules in this population: complement component (C)-3, toll-like receptor (TLR)-4, and C-reactive protein (CRP). We enrolled 16 HEU and 6 HIV-unexposed (HU) infants. TLR4 function was investigated by stimulating whole blood with increasing concentrations of TLR4-agonist ultrapure lipopolysaccharides. TLR4/TLR4-agonist dose response were assessed by measuring IL-6 secretion. Complement C3 and CRP were measured by photo spectrometry. Data showed no significant differences in baseline concentration of CRP between HEU and HU infants. Complement C3 was significantly higher in HEU infants than HU infants. TLR4 anergy was observed in 7 of 12 HEU infants, whereas the rest of HEU infants (n = 4) and the control HU infants tested (n = 3) showed responsive TLR4. None of the HEU infants investigated in this study had severe infections in the year after their birth. In conclusion, TLR4 anergy can occur in HEU infants without necessarily translating to increased vulnerability to infectious diseases.

Surviving and Thriving-Shifting the Public Health Response to HIV-Exposed Uninfected Children: Report of the 3rd HIV-Exposed Uninfected Child Workshop

Great gains were achieved with the introduction of the United Nations' Millennium Development Goals, including improved child survival. Transition to the Sustainable Development Goals (SDGs) focused on surviving, thriving, and transforming, representing an important shift to a broader public health goal, the achievement of which holds the promise of longer-term individual and societal benefits. A similar shift is needed with respect to outcomes for infants born to women living with HIV (WLHIV). Programming to prevent vertical HIV transmission has been successful in increasingly achieving a goal of HIV-free survival for infants born to WLHIV. Unfortunately, HIV-exposed uninfected (HEU) children are not achieving comparable health and developmental outcomes compared with children born to HIV-uninfected women under similar socioeconomic circumstances. The 3rd HEU Child Workshop, held as a satellite session of the International AIDS Society's 9th IAS Conference in Paris in July 2017, provided a venue to discuss HEU child health and development disparities. A summary of the Workshop proceedings follows, providing current scientific findings, emphasizing the gap in systems for long-term monitoring, and highlighting the public health need to establish a strategic plan to better quantify the short and longer-term health and developmental outcomes of HEU children.

Breastfeeding Behaviors and the Innate Immune System of Human Milk: Working Together to Protect Infants against Inflammation, HIV-1, and Other Infections

The majority of infants’ breastfeeding from their HIV-infected mothers do not acquire HIV-1 infection despite exposure to cell-free virus and cell-associated virus in HIV-infected breast milk. Paradoxically, exclusive breastfeeding regardless of the HIV status of the mother has led to a significant decrease in mother-to-child transmission (MTCT) compared with non-exclusive breastfeeding. Although it remains unclear how these HIV-exposed infants remain uninfected despite repeated and prolonged exposure to HIV-1, the low rate of transmission is suggestive of a multitude of protective, short-lived bioactive innate immune factors in breast milk. Indeed, recent studies of soluble factors in breast milk shed new light on mechanisms of neonatal HIV-1 protection. This review highlights the role and significance of innate immune factors in HIV-1 susceptibility and infection. Prevention of MTCT of HIV-1 is likely due to multiple factors, including innate immune factors such as lactoferrin and elafin among many others. In pursuing this field, our lab was the first to show that soluble toll-like receptor 2 (sTLR2) directly inhibits HIV infection, integration, and inflammation. More recently, we demonstrated that sTLR2 directly binds to selective HIV-1 proteins, including p17, gp41, and p24, leading to significantly reduced NFκB activation, interleukin-8 production, CCR5 expression, and HIV infection in a dose-dependent manner. Thus, a clearer understanding of soluble milk-derived innate factors with known antiviral functions may provide new therapeutic insights to reduce vertical HIV-1 transmission and will have important implications for protection against HIV-1 infection at other mucosal sites. Furthermore, innate bioactive factors identified in human milk may serve not only in protecting infants against infections and inflammation but also the elderly; thus, opening the door for novel innate immune therapeutics to protect newborns, infants, adults, and the elderly.

Intestinal Damage and Inflammatory Biomarkers in Human Immunodeficiency Virus (HIV)-Exposed and HIV-Infected Zimbabwean Infants

Background

Disease progression is rapid in human immunodeficiency virus (HIV)–infected infants. Whether intestinal damage and inflammation underlie mortality is unknown.

Methods

We measured plasma intestinal fatty acid binding protein (I-FABP), soluble CD14 (sCD14), interleukin 6 (IL-6), and C-reactive protein (CRP) at 6 weeks and 6 months of age in 272 HIV-infected infants who either died (cases) or survived (controls), and in 194 HIV-exposed uninfected (HEU) and 197 HIV-unexposed infants. We estimated multivariable odds ratios for mortality and postnatal HIV transmission for each biomarker using logistic regression.

Results

At 6 weeks, HIV-infected infants had higher sCD14 and IL-6 but lower I-FABP than HIV-exposed and HIV-unexposed infants (P < .001). CRP was higher in HIV-exposed than HIV-unexposed infants (P = .02). At 6 months, HIV-infected infants had highest sCD14, IL-6, and CRP concentrations (P < .001) and marginally higher I-FABP than other groups (P = .07). CRP remained higher in HIV-exposed vs HIV-unexposed infants (P = .04). No biomarker was associated with mortality in HIV-infected infants, or with odds of breast-milk HIV transmission in HIV-exposed infants.

Conclusions

HIV-infected infants have elevated inflammatory markers by 6 weeks of age, which increase over time. In contrast to adults and older children, inflammatory biomarkers were not associated with mortality. HEU infants have higher inflammation than HIV-unexposed infants until at least 6 months, which may contribute to poor health outcomes.

Child Growth According to Maternal and Child HIV Status in Zimbabwe

BACKGROUND

Growth failure is common among HIV-infected infants, but there are limited data on the effects of HIV exposure or timing of HIV acquisition on growth.

METHODS

Fourteen thousand one hundred ten infants were enrolled in the Zimbabwe Vitamin A for Mothers and Babies trial in Zimbabwe before the availability of antiretroviral therapy or co-trimoxazole. Anthropometric measurements were taken from birth through 12-24 months of age. Growth outcomes were compared between 5 groups of children: HIV-infected in utero (IU), intrapartum (IP) or postnatally (PN); HIV-exposed uninfected (HEU); and HIV unexposed.

RESULTS

Growth failure was common across all groups of children. Compared with HIV-unexposed children, IU-, IP- and PN-infected children had significantly lower length-for-age and weight-for-length Z scores throughout the first 2 years of life. At 12 months, odds ratios for stunting were higher in IU [6.25, 95% confidence interval (CI): 4.20-9.31] and IP infants (4.76, 95% CI: 3.58-6.33) than in PN infants (1.70, 95% CI: 1.16-2.47). Compared with HIV-unexposed infants, HEU infants at 12 months had odds ratios for stunting of 1.23 (95% CI: 1.08-1.39) and wasting of 1.56 (95% CI: 1.22-2.00).

CONCLUSIONS

HIV-infected infants had very high rates of growth failure during the first 2 years of life, particularly if IU or IP infected, highlighting the importance of early infant diagnosis and antiretroviral therapy. HEU infants had poorer growth than HIV-unexposed infants in the first 12 months of life.

Cytomegalovirus viraemia is associated with poor growth and T-cell activation with an increased burden in HIV-exposed uninfected infants

Objective:

Factors associated with poor health in HIV-exposed-uninfected (HEU) infants are poorly defined. We describe the prevalence and correlates of cytomegalovirus (CMV) viraemia in HEU and HIV-unexposed-uninfected (HUU) infants, and quantify associations with anthropometric, haematological, and immunological outcomes.

Design:

Cross-sectional, including HEU and HUU infants from rural coastal Kenya.

Methods:

Infants aged 2–8 months were studied. The primary outcome was CMV viraemia and viral load, determined by quantitative PCR. Correlates were tested by logistic and linear regression; coefficients were used to describe associations between CMV viraemia and clinical/immunological parameters.

Results:

In total, 42 of 65 (64.6%) infants had CMV viraemia [median viral load, 3.0 (interquartile ranges: 2.7–3.5) log₁₀ IU/ml]. Compared to community controls, HEU infants had six-fold increased odds of being viraemic (adjusted odds ratio 5.95 [95% confidence interval: 1.82–19.36], P = 0.003). Age, but not HEU/HUU status, was a strong correlate of CMV viral load (coefficient = −0.15, P = 0.009). CMV viral load associated negatively with weight-for-age (WAZ) Z-score (coefficient =  −1.06, P = 0.008) and head circumference-for-age Z-score (coefficient =  −1.47, P = 0.012) and positively with CD8⁺ T-cell coexpression of CD38/human leucocyte antigen DR (coefficient = 15.05, P = 0.003).

Conclusion:

The odds of having CMV viraemia was six-fold greater in HEU than HUU infants when adjusted for age. CMV viral load was associated with adverse growth and heightened CD8⁺ T-cell immune activation. Longitudinal assessments of the clinical effects of primary CMV infection and associated immunomodulation in early life in HEU and HUU populations are warranted.

Cytomegalovirus Acquisition and Inflammation in Human Immunodeficiency Virus-Exposed Uninfected Zimbabwean Infants

Cytomegalovirus (CMV) acquisition and inflammation were evaluated in 231 human immunodeficiency virus (HIV)–exposed uninfected (HEU) and 100 HIV-unexposed Zimbabwean infants aged 6 weeks. The HEU and HIV-unexposed infants had a similarly high prevalence of CMV (81.4% vs 74.0%, respectively; P = .14), but HEU infants had higher CMV loads (P = .005) and >2-fold higher C-reactive protein (CRP) concentrations (P < .0001). The CMV-positive HEU infants had higher CRP than the CMV-negative HEU infants; this association disappeared after adjusting for maternal HIV load. Overall, CMV acquisition is high in early life, but HEU infants have higher CMV loads and a proinflammatory milieu, which may be driven partly by maternal HIV viremia.

Altered Natural Killer Cell Function in HIV-Exposed Uninfected Infants

Objectives

HIV-exposed uninfected (HEU) infants have higher rates of severe and fatal infections compared with HIV-unexposed (HUU) infants, likely due to immune perturbations. We hypothesized that alterations in natural killer (NK) cell activity might occur in HEU infants and predispose them to severe infections.

Design

Case–control study using cryopreserved peripheral blood mononuclear cells (PBMCs) at birth and 6 months from HEU infants enrolled from 2002 to 2009 and HUU infants enrolled from 2011 to 2013.

Methods

NK cell phenotype and function were assessed by flow cytometry after 20-h incubation with and without K562 cells.

Results

The proportion of NK cells among PBMCs was lower at birth in 12 HEU vs. 22 HUU (1.68 vs. 10.30%, p < 0.0001) and at 6 months in 52 HEU vs. 72 HUU (3.09 vs. 4.65%, p = 0.0005). At birth, HEU NK cells demonstrated increased killing of K562 target cells (p < 0.0001) and increased expression of CD107a (21.65 vs. 12.70%, p = 0.047), but these differences resolved by 6 months. Stimulated HEU NK cells produced less interferon (IFN)γ at birth (0.77 vs. 2.64%, p = 0.008) and at 6 months (4.12 vs. 8.39%, p = 0.001), and showed reduced perforin staining at 6 months (66.95 vs. 77.30%, p = 0.0008). Analysis of cell culture supernatants indicated that lower NK cell activity in HEU was associated with reduced interleukin (IL)-12, IL-15, and IL-18. Addition of recombinant human IL-12 to stimulated HEU PBMCs restored IFNγ production to that seen in stimulated HUU cultures.

Conclusion

NK cell proportion, phenotype, and function are altered in HEU infants. NK cell cytotoxicity and degranulation are increased in HEU at birth, but HEU NK cells have reduced IFNγ and perforin production, suggesting an adequate initial response, but decreased functional reserve. NK cell function improved with addition of exogenous IL-12, implicating impaired production of IL-12 by accessory cells. Alterations in NK cell and accessory cell function may contribute to the increased susceptibility to infection in HEU infants.

Stunting Mediates the Association between Small-for-Gestational-Age and Postneonatal Mortality

BACKGROUND

In sub-Saharan Africa, one-third of all births are small for gestational age (SGA), and 4.4 million children are stunted; both conditions increase the risk of child mortality. SGA has also been shown to increase the risk of stunting.

OBJECTIVE

We tested whether the association between SGA and postneonatal mortality is mediated by stunting.

METHODS

We used longitudinal data from children aged 6 wk to 24 mo (n = 12,155) enrolled in the ZVITAMBO (Zimbabwe Vitamin A for Mothers and Babies) trial. HIV exposure was defined based on maternal HIV status at baseline. SGA was defined as birthweight <10th percentile of the INTERGROWTH-21st (International Fetal and Newborn Growth Consortium for the 21st Century) standards. We used a standard mediation approach by comparing the attenuation of the risk when the mediator was added to the model. We used Cox proportional hazards models first to regress SGA on postneonatal mortality, controlling for age. Stunting (length-for-age z score <-2) was then included in the model to test mediation.

RESULTS

Approximately 20% of children were term SGA, and 23% were stunted before their last follow-up visit. In this cohort, 31% of children were exposed to HIV; the HIV-exposed group represented a pooled group of HIV-infected and HIV-exposed but uninfected children. Postneonatal mortality was significantly higher among children born SGA (HR: 1.5; 95% CI: 1.3, 1.7). This association was attenuated and not statistically significant when stunting was included in the model, suggesting a mediation effect (HR: 1.1; 95% CI: 0.91, 1.3). When stratified by HIV exposure status, we observed a significant attenuation of the risk, suggesting mediation, only among HIV-exposed children (model 1, HR: 1.3; 95% CI: 1.1, 1.6; model 2, HR: 1.1; 95% CI: 0.88, 1.3).

CONCLUSIONS

This analysis aids in investigating pathways that underlie an observed SGA-mortality relation and may inform survival interventions in undernourished settings.

Linking Susceptibility to Infectious Diseases to Immune System Abnormalities among HIV-Exposed Uninfected Infants

HIV-exposed uninfected (HEU) infants experience increased overall mortality from infectious causes when compared to HIV-unexposed uninfected (HU) infants. This is the case in both the resource-rich and resource-limited settings. Here, we explore the concept that specific types of infectious diseases that are more common among HEU infants could provide clues as to the potential underlying immunological abnormalities. The most commonly reported infections in HEU vs. HU infants are caused by encapsulated bacteria, suggesting the existence of a less effective humoral (antibody, complement) immune response. Decreased transplacental transfer of protective maternal antibodies has consistently been observed among HEU newborns, suggesting that this may indeed be one of the key drivers of their susceptibility to infections with encapsulated bacteria. Reassuringly, HEU humoral response to vaccination appears to be well conserved. While there appears to be an increase in overall incidence of acute viral infections, no specific pattern of acute viral infections has emerged; and although there is evidence of increased chronic viral infection from perinatal transmission of hepatitis C and cytomegalovirus, no data exist to suggest an increase in adverse outcomes. Thus, no firm conclusions about antiviral effector mechanisms can be drawn. However, the most unusual of reported infections among the HEU have been opportunistic infections, suggesting the possibility of underlying defects in CD4 helper T cells and overall immune regulatory function. This may relate to the observation that the immunological profile of HEUs indicates a more activated T cell profile as well as a more inflammatory innate immune response. However, both of these observations appear transient, marked in early infancy, but no longer evident later in life. The causes of these early-life changes in immune profiles are likely multifactorial and may be related to in utero exposure to HIV, but also to increased environmental exposure to pathogens from sicker household contacts, in utero and postnatal antiretroviral drug exposure, and, in certain circumstances, differences in mode of feeding. The relative importance of each of these factors will be important to delineate in an attempt to identify those HEU at highest risk of adverse outcomes for targeted interventions.