Bone mineral loss through increased bone turnover in HIV-infected children treated with highly active antiretroviral therapy

Health-Related Physical Fitness Evaluation in HIV-Diagnosed Children and Adolescents: A Scoping Review

BACKGROUND

Health-related physical fitness has been widely used to investigate the adverse effects of HIV infection/ART in children and adolescents. However, methods/protocols and cut-points applied for investigating health-related physical fitness are not clear. The aim of this scoping review was to map the literature to identify gaps in knowledge regarding the methods/protocols and cut-points.

METHODS

A scoping review, following the Joana Briggs Institute (JBI) guidelines, was conducted through ten major databases. Search followed the PCC strategy to construct block of terms related to population (children and adolescents), concept (health-related physical fitness components) and context (HIV infection).

RESULTS

The search resulted in 7545 studies. After duplicate removal, titles and abstracts reading and full text assessment, 246 studies were included in the scoping review. Body composition was the most investigated component (n = 244), followed by muscular strength/endurance (n = 23), cardiorespiratory fitness (n = 15) and flexibility (n = 4). The World Health Organization growth curves, and nationals' surveys were the most reference values applied to classify body composition (n = 149), followed by internal cut-points (n = 30) and cut-points developed through small populations (n = 16). Cardiorespiratory fitness was classified through cut-points from three different assessment batteries, as well as cut-points developed through studies with small populations, muscular strength/endurance and flexibility were classified through the same cut-points from five different assessment batteries.

CONCLUSIONS

The research on muscular strength/endurance, cardiorespiratory fitness and flexibility has been scarcely explored. The lack of studies that investigated method usability as well as reference values was evidenced.

Bone health in HIV-infected children on antiretroviral therapy: An Indian study

Aim:

The aim of this study is to determine the bone health in HIV-infected children on antiretroviral therapy (ART).

Materials and Methods:

This cross-sectional study was carried out in 31 HIV-infected children aged 5–18 years. Each patient underwent testing for serum calcium, phosphorous, alkaline phosphatase, and 25(OH) Vitamin D. Bone mineral density (BMD) was done using a DXA scanner. Patients' z scores for BMD of the lumbar spine and left femoral neck were noted. The factors associated with low BMD were analyzed.

Results:

Seven (22.6%) children had a low spinal BMD and 6 (19.4%) had low femoral neck BMD. Low serum calcium was seen in 6 (19.4%) patients and high alkaline phosphatase was seen in 15 (48.4%) patients. Low serum 25 (OH) Vitamin D levels were present in 30 (96.8%) patients, whereas all the patients had normal serum phosphorous. Duration of ART in those with low spinal BMD was 4.6 ± 3.4 years as compared to 6.4 ± 3.2 years in those with normal spinal BMD (P = 0.235) and for low left femoral neck BMD was 3.9 ± 2 years as compared to 6.5 ± 3.4 years for those with normal femoral neck BMD (P = 0.031). Mean 25(OH) Vitamin D levels were 8.4 ± 2.8 ng/ml in those with low femoral neck BMD as compared to 13.6 ± 8.3 ng/ml in those with normal femoral neck BMD (P = 0.015). Type of ART did not have any association with low BMD.

Conclusion:

Over 95% of HIV-infected children have low 25(OH) Vitamin D levels which affect the appendicular BMD. BMD is affected more in children who have been on ART for a shorter time. No particular ART regimen is associated with low BMD.

Persistently lower bone mass and bone turnover among South African children living with well controlled HIV

OBJECTIVE

We evaluated longitudinal trends and associations between bone mass, bone turnover and inflammatory markers among South African children living with HIV (CLHIV) and controls.

DESIGN

We previously reported decreased bone mass among CLHIV independent of marked inflammation and increased bone turnover. The goal of this study was to evaluate longitudinal changes in bone mass, bone turnover and inflammation over 2 years.

METHODS

Longitudinal analyses were conducted among 220 CLHIV and 220 controls. Anthropometric measurements, physical activity, antiretroviral regimen, virologic and immunologic status, whole body (WB) and lumbar spine (LS) bone mineral content (BMC) and bone mineral density (BMD) were collected (enrollment, 12 and 24 months). Bone turnover markers including C-telopeptide of type I collagen (CTx) and procollagen type I N-terminal propeptide (P1NP) and inflammatory markers including interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), soluble CD14 and high-sensitivity C-reactive protein (hsCRP) were collected at enrollment and 24 months.

RESULTS

Compared with controls, CLHIV had significantly lower mean WB-BMC, WB-BMD, WB-BMC z scores, LS-BMC and LS-BMD as well as lower bone formation (P1NP) and resorption (CTx), and higher hsCRP and soluble CD14 over 24 months. CLHIV on efavirenz (EFV) had consistently lower TNF-alpha and IL-6 compared with those on ritonavir-boosted lopinavir (LPV/r) at all time points.

CONCLUSION

Over 2 years of follow-up, South African CLHIV had persistently lower bone mass, bone turnover, and macrophage activation. Lower bone mass and higher pro-inflammatory cytokine profiles were consistently observed among those on LPV/r-based compared with EFV-based regimens.

Impact of HIV-1 Infection and Antiretroviral Therapy on Bone Homeostasis and Mineral Density in Vertically Infected Patients

Daily assumption of antiretroviral drugs and HIV-related immune activation lead to important side effects, which are particularly evident in vertically infected patients. Bone homeostasis impairment and reduction of bone mineral density (BMD) is one of the most important side effects. Primary aim of this study is to assess the prevalence of bone homeostasis alterations in a group of vertically infected patients; secondary aim is to analyze the relationship between bone homeostasis alterations and anthropometric data, severity of HIV infection, and antiretroviral therapy. We studied 67 patients with vertically transmitted HIV-1 (aged 6-31 years), followed by the Pediatric Infectious Disease Unit of the University Hospital of Padua, Italy. We analyzed bone turnover markers (P1NP and CTx) and we performed lumbar spine and femoral dual energy X-ray absorption densitometry (DXA). Personal and anthropometric data and information on HIV-infection severity and antiretroviral therapy were collected for all patients. We found that BMD values recorded by DXA showed a significant correlation with age, race, BMI, physical activity, and antiretroviral therapy duration. P1NP was increased in 43% of patients, while CTX in 61% of them. P1NP alteration was related to age, race, BMI, physical activity, therapy duration, and ever use of protease inhibitors and nucleotide reverse transcriptase inhibitors. CTX alteration was found to be correlated only with age. In conclusion, our study confirms that a wide percentage of HIV vertically infected patients show reduced BMD and impaired bone homeostasis. Strict monitoring is needed in order to early identify and treat these conditions.

Decreased bone turnover in HIV-infected children on antiretroviral therapy

In this study, we evaluated the relationships between immune activation, bone turnover, and bone mass in virally suppressed HIV-infected children and HIV-uninfected children in South Africa. We found that decreased bone mass may occur or persist independent of immune activation and altered bone turnover.

PURPOSE

HIV-infected children and adolescents have deficits in skeletal growth which include decreases in bone mass and alterations in bone microarchitecture. However, the mechanism by which HIV infection compromises bone accrual in children and adolescents is unclear. The goal of this study was to evaluate the relationships between immune activation, bone turnover, and bone mass in a group of pre-pubertal HIV-infected children randomized to remain on ritonavir-boosted lopinavir (LPV/r)-based antiretroviral therapy (ART) or switch to efavirenz-based ART in South Africa virally suppressed at the time of this study.

METHODS

This cross-sectional analysis included 219 HIV-infected and 180 HIV-uninfected children enrolled in the CHANGES Bone Study conducted in Johannesburg, South Africa. Whole body (WB) bone mineral content (BMC) was assessed by dual x-ray absorptiometry and WB BMC Z-scores adjusted for sex, age, and height were generated. Bone turnover markers, including C-telopeptide of type 1 collagen (CTx) and procollagen type I N-terminal propeptide (P1NP), were analyzed. Markers of immune activation were also measured, including cytokines IL-6 and TNF-alpha, as well as soluble CD14 and high-sensitivity C-reactive protein (CRP).

RESULTS

Compared to uninfected controls, HIV-infected children had lower WB BMC Z-scores, similar IL-6 and TNF-alpha, higher soluble CD14 and high-sensitivity CRP, and lower markers of bone resorption (CTX) and bone formation (P1NP). Bone turnover markers were not different in those remaining on LPV/r or switched to efavirenz.

CONCLUSIONS

Our findings suggest that in HIV-infected children with viral suppression, decreased bone accrual may occur or persist independent of immune activation and altered bone turnover.

Hepatic, Renal, Hematologic, and Inflammatory Markers in HIV-Infected Children on Long-term Suppressive Antiretroviral Therapy

BACKGROUND

Data on long-term toxicity of antiretroviral therapy (ART) in HIV-infected children are sparse. PENPACT-1 was an open-label trial in which HIV-infected children were assigned randomly to receive protease inhibitor (PI)- or nonnucleoside reverse-transcriptase inhibitor (NNRTI)-based ART.

METHODS

We examined changes in clinical, immunologic, and inflammatory markers from baseline to year 4 in the subset of children in the PENPACT-1 study who experienced viral suppression between week 24 and year 4 of ART. Liver enzyme, creatinine, and cholesterol levels and hematologic parameters were assessed during the trial. Cystatin C, high-sensitivity C-reactive protein (hs-CRP), interleukin 6 (IL-6), d-dimer, and soluble CD14 (sCD14) were assayed from cryopreserved specimens.

RESULTS

Ninety-nine children (52 on PI-based and 47 on NNRTI-based ART) met inclusion criteria. The median age at initiation of ART was 6.5 years (interquartile range [IQR], 3.7-13.4 years), and 22% were aged <3 years at ART initiation; 56% of the PI-treated children received lopinavir/ritonavir, and 70% of NNRTI-treated children received efavirenz initially. We found no evidence of significant clinical toxicity in either group; growth, liver, kidney, and hematologic parameters either remained unchanged or improved between baseline and year 4. Total cholesterol levels increased modestly, but no difference between the groups was found. IL-6 and hs-CRP levels decreased more after 4 years in the NNRTI-based ART group. The median change in IL-6 level was -0.35 pg/ml in the PI-based ART group and -1.0 in the NNRTI-based ART group (P = .05), and the median change in hs-CRP level was 0.25 µg/ml in the PI-based ART group and -0.95 µg/ml in the NNRTI-based ART group (P = .005).

CONCLUSION

These results support the safety of prolonged ART use in HIV-infected children and suggest that suppressive NNRTI-based regimens can be associated with lower levels of systemic inflammation.

Renal and Bone Adverse Effects of a Tenofovir-Based Regimen in the Treatment of HIV-Infected Children: A Systematic Review

INTRODUCTION

Tenofovir disoproxil fumarate (TDF)-containing regimens in the treatment of HIV-infected children have safety concerns with respect to renal and bone toxicity.

OBJECTIVE

The aim of this study was to systematically review and critically appraise the literature relating to the reported renal and bone adverse effects of TDF-based regimens in the treatment of HIV-infected children from 2 to 19 years old.

METHODS

Searches were performed using the Cochrane Central Register of Controlled Trials (CENTRAL), Cumulative Index to Nursing and Allied Health Literature (CINAHL), MEDLINE, OvidSP, ScienceDirect and Web of Science databases and platforms. All primary studies involving tenofovir use in HIV-infected children were sought. Studies that involved the use of TDF for pre- and post-exposure prophylaxis, and treatment of chronic hepatitis B virus infection were excluded. Data on study characteristics, participant's characteristics, therapeutic intervention and adverse effects were extracted using a piloted tool. In addition, pharmacovigilance data from the WHO Adverse Reaction database were included.

RESULTS

We identified 19 studies that reported the presence of renal and bone adverse effects of TDF and these included a total of 1100 study participants. The reports were in distinctly heterogeneous participant groups. A total of 287 renal and bone adverse effects were reported (250 renal and 37 bone adverse effects). Approximately 238 (21.6 %) participants were affected by these adverse effects. Of these, 15 participants stopped their TDF-containing regimen due to these adverse effects. In addition, the pharmacovigilance data from the WHO Adverse Reaction database reported 101 renal and bone adverse effects for patients whose indication was HIV/AIDS.

CONCLUSION

This systematic review summarises the reports of renal and bone adverse effects of a TDF-containing regimen in the treatment of HIV-infected children. Our findings suggest that the benefits of using TDF in children need to be balanced against the potential risk of toxicity.

Efavirenz is associated with higher bone mass in South African children with HIV

BACKGROUND

We investigate if switching from a ritonavir-boosted lopinavir (LPV/r)-based to an efavirenz-based antiretroviral therapy (ART) regimen is associated with beneficial bone development.

METHODS

The CHANGES Bone Study follows HIV-infected children who participated in a noninferiority randomized trial in Johannesburg, South Africa evaluating the safety and efficacy of preemptive switching to efavirenz (n = 106) compared with remaining on LPV/r (n = 113). HIV-uninfected children were also recruited. Whole-body and lumbar spine bone mineral content (BMC) were assessed by dual-energy X-ray absorptiometry at a cross-sectional visit. BMC Z-scores adjusted for sex, age, and height were generated. Physical activity and dietary intake were assessed. CD4 percentage and viral load were measured. We compared bone indices of HIV-infected with HIV-uninfected children and LPV/r with efavirenz by intent-to-treat.

RESULTS

The 219 HIV-infected (52% boys) and 219 HIV-uninfected (55% boys) children were 6.4 and 7.0 years of age, respectively. Mean ART duration for HIV-infected children was 5.7 years. Whole-body BMC Z-score was 0.17 lower for HIV-infected children compared with HIV-uninfected children after adjustment for physical activity, dietary vitamin D and calcium (P = 0.03). Whole-body BMC Z-score was 0.55 higher for HIV-infected children switched to efavirenz compared with those remaining on LPV/r after adjustment for physical activity, dietary vitamin D and calcium, CD4 percentage, and viral load (P < 0.0001).

CONCLUSION

South African HIV-infected children receiving ART have lower bone mass compared with HIV-uninfected controls. Accrued bone mass is positively associated with switching to efavirenz-based ART compared with remaining on LPV/r, providing additional rationale for limiting LPV/r exposure once viral suppression has been achieved.

Physiological and pathophysiological bone turnover - role of the immune system

Osteoporosis develops when the rate of osteoclastic bone breakdown (resorption) exceeds that of osteoblastic bone formation, which leads to loss of BMD and deterioration of bone structure and strength. Osteoporosis increases the risk of fragility fractures, a cause of substantial morbidity and mortality, especially in elderly patients. This imbalance between bone formation and bone resorption is brought about by natural ageing processes, but is frequently exacerbated by a number of pathological conditions. Of importance to the aetiology of osteoporosis are findings over the past two decades attesting to a deep integration of the skeletal system with the immune system (the immuno-skeletal interface (ISI)). Although protective of the skeleton under physiological conditions, the ISI might contribute to bone destruction in a growing number of pathophysiological states. Although numerous research groups have investigated how the immune system affects basal and pathological osteoclastic bone resorption, recent findings suggest that the reach of the adaptive immune response extends to the regulation of osteoblastic bone formation. This Review examines the evolution of the field of osteoimmunology and how advances in our understanding of the ISI might lead to novel approaches to prevent and treat bone loss, and avert fractures.

The physical and psychological effects of HIV infection and its treatment on perinatally HIV-infected children

INTRODUCTION

As highly active antiretroviral therapy (HAART) transforms human immunodeficiency virus (HIV) into a manageable chronic disease, new challenges are emerging in treating children born with HIV, including a number of risks to their physical and psychological health due to HIV infection and its lifelong treatment.

METHODS

We conducted a literature review to evaluate the evidence on the physical and psychological effects of perinatal HIV (PHIV+) infection and its treatment in the era of HAART, including major chronic comorbidities.

RESULTS AND DISCUSSION

Perinatally infected children face concerning levels of treatment failure and drug resistance, which may hamper their long-term treatment and result in more significant comorbidities. Physical complications from PHIV+ infection and treatment potentially affect all major organ systems. Although treatment with antiretroviral (ARV) therapy has reduced incidence of severe neurocognitive diseases like HIV encephalopathy, perinatally infected children may experience less severe neurocognitive complications related to HIV disease and ARV neurotoxicity. Major metabolic complications include dyslipidaemia and insulin resistance, complications that are associated with both HIV infection and several ARV agents and may significantly affect cardiovascular disease risk with age. Bone abnormalities, particularly amongst children treated with tenofovir, are a concern for perinatally infected children who may be at higher risk for bone fractures and osteoporosis. In many studies, rates of anaemia are significantly higher for HIV-infected children. Renal failure is a significant complication and cause of death amongst perinatally infected children, while new data on sexual and reproductive health suggest that sexually transmitted infections and birth complications may be additional concerns for perinatally infected children in adolescence. Finally, perinatally infected children may face psychological challenges, including higher rates of mental health and behavioural disorders. Existing studies have significant methodological limitations, including small sample sizes, inappropriate control groups and heterogeneous definitions, to name a few.

CONCLUSIONS

Success in treating perinatally HIV-infected children and better understanding of the physical and psychological implications of lifelong HIV infection require that we address a new set of challenges for children. A better understanding of these challenges will guide care providers, researchers and policymakers towards more effective HIV care management for perinatally infected children and their transition to adulthood.

Sclerostin and DKK-1: two important regulators of bone metabolism in HIV-infected youths

Reduced bone mineral density (BMD) and altered bone metabolism are common findings in HIV-infected patients. Increased bone formation has been described both in HIV-infected adults and children. Wnt ligands promote bone formation by stimulating osteoblast differentiation and their survival. Sclerostin and dickkopf factor 1 (DKK-1), Wnt antagonists, are important negative regulators of bone formation. We studied 86 HIV-infected patients whose ages ranged from 5.7 to 27.9 years. Patients were all on antiretroviral therapy, but seven who were naïve to treatment. Bone alkaline phosphatase (BAP), sclerostin, and DKK-1 were measured in serum by enzyme immunoassay. BMD was measured by dual-energy X-ray absorptiometry at the lumbar spine and in the whole skeleton. Biochemical indexes were also measured in 143 healthy controls (age range 4.5-27.4 years). HIV-infected patients had lower than normal BMD (spine P < 0.005, and whole skeleton P < 0.03). BAP measurements were significantly higher in HIV-infected patients than controls (P ≤ 0.05). Sclerostin and DKK-1 concentrations were markedly lower than in controls (P ≤ 0.0006, and P ≤ 0.03, respectively). The serum concentration of both analytes of patients naïve to antiretroviral treatment was not different from that of treated patients. No correlations were found between sclerostin, DKK-1, and bone mineral measurements. Our data confirm the alteration of bone metabolism pathways in HIV-infected individuals. The lower concentration of Wnt antagonists is consistent with the increased bone formation markers.

Nutritional Care of the Child with Human Immunodeficiency Virus Infection in the United States

In well-resourced settings, early infant diagnosis and administration of life-saving antiretrovirals (ARVs) have significantly improved clinical outcomes in pediatric human immunodeficiency virus (HIV) infection. The dramatic increase in survival rates is associated with enhancements in overall quality of life, which reflect a multidisciplinary, holistic approach to care. Current optimism starkly contrasts with the outlook and prognosis two decades ago, when failure to thrive and wasting syndrome from uncontrolled pediatric HIV infection resulted from poor oral intake, malabsorption, chronic diarrhea, and a persistently catabolic state. The tenets of care developed from that era still hold true in that all infants, children, and adolescents with HIV require comprehensive nutritional services in addition to effective combination antiretroviral therapy (cART). This chapter will review the principles of nutrition in the pre- and post-cART eras and discuss the etiologic factors associated with malnutrition, with an emphasis on interventions that have favorably impacted the growth and body composition of infants, children and adolescents with HIV.

Bone health in HIV-infected children, adolescents and young adults: a systematic review

BACKGROUND

Children and adolescents, who either acquire HIV infection perinatally, from contaminated blood products or via sexual transmission early in life, have the greatest cumulative exposure to the negative direct and indirect effects of HIV infection and ART on bone, which may lead to increased lifetime risk for osteoporosis and fracture. We conducted a systematic review to evaluate the literature on bone health in children and adolescents with HIV.

METHODS

We performed a comprehensive search of the Medline, Scopus, and Cochrane Library databases (up to April 1, 2014) for studies that reported on bone imaging or bone fractures in HIV-infected children, adolescents, or young adults.

RESULTS

A total of 32 publications met our inclusion criteria. Seventeen studies were cross-sectional and 15 were longitudinal. The majority of studies were conducted in high-income countries, three in middle-income countries and none in low-income countries. Overall, the studies we reviewed indicate that measures of bone mass are reduced, with increased prevalence of low BMD in children and adolescents with HIV. However, the studies are highly variable with respect to comparison sources, measurement methods, adjustment techniques for body size or growth retardation, and highlighted risk factors, including aspects related to medication exposures as well as the effects of HIV infection per se.

CONCLUSION

HIV infection appears to be associated with decreased bone accrual throughout childhood and adolescence. Initial studies indicate that sub-optimal bone accrual may be persistent and result in reduced peak bone mass, an important determinant of future risk of osteoporosis and fracture. Important areas for future research include evaluation of bone mass, bone quality and fracture risk across the life course among those with early-life infection with HIV, particularly in resource-limited settings where the majority of children with HIV live.

Metabolic complications of in utero maternal HIV and antiretroviral exposure in HIV-exposed infants

BACKGROUND

Despite a wide body of literature supporting the use of antenatal antiretrovirals (ARV) for the prevention of mother-to-child transmission, there remains a need for continued monitoring as the intrauterine interval is a critical period during which fetal programming influences the future health and development of the child.

METHODS

We conducted a systematic review of the current literature addressing potential metabolic complications of in utero HIV and ARV exposure. We describe studies evaluating metabolic outcomes such as intrauterine and early postnatal growth, bone health and mitochondrial toxicity.

RESULTS

Overall, infants exposed to HIV/ARV do not appear to exhibit vastly compromised intrauterine or early postnatal growth. However, some studies on the effect of combination antiretroviral therapy on small for gestational age and low birth weight outcomes in low-middle income countries show a risk for small for gestational age/low birth weight while those in the United States do not. Postnatal growth to 1 year does not appear to be affected by intrauterine tenofovir exposure in African studies, but a US study found statistically significant differences in length for age z scores (LAZ) at 1 year. Little data exists on long-term bone health. Mitochondrial toxicity including abnormal mitochondrial morphology and DNA content, as well as neurologic deficits and death, have been demonstrated in HIV/ARV-exposed infants.

CONCLUSION

Although gross measures of metabolic well-being appear to be reassuring, careful vigilance of even small risks for potential serious adverse effects to infants exposed to intrauterine HIV/ARVs is warranted as intrauterine fetal metabolic programming may substantially impact the future health of the child.

Antiretroviral therapy and mother-to-child transmission of HIV-1

The advent of highly active antiretroviral therapy has facilitated the virtual elimination of mother-to-child transmission of HIV infection in developed countries, reducing transmission rates to approximately 1 to 2%. In these settings, highly active antiretroviral therapy has also transformed pediatric HIV infection into a chronic disease; although there are associated costs in terms of side effects and the heavy pill burden. In less developed settings, easier-to-use adaptations of antiretroviral therapy regimens, such as short-course and single-dose antiretroviral strategies or neonatal postexposure prophylaxis can also substantially prevent mother-to-child transmission, although to a lesser degree than highly active antiretroviral therapy. However, postnatal transmission of infection through breastfeeding significantly reduces the longer-term efficacy of these strategies. Ongoing research is focusing on the use of antiretroviral therapy in the breastfeeding period.

Early loss of bone mineral density is correlated with a gain of fat mass in patients starting a protease inhibitor containing regimen: the prospective Lipotrip study

BACKGROUND

HIV-infected patients starting antiretroviral treatment (ART) experience deep and early disorders in fat and bone metabolism, leading to concomitant changes in fat mass and bone mineral density.

METHODS

We conducted a prospective study in treatment-naive HIV-infected patients randomized to receive two nucleoside reverse transcriptase inhibitors in combination with either a protease inhibitor (PI) or a non-nucleosidic reverse transcriptase inhibitor (NNRTI), to evaluate early changes in body composition, bone mineral density and metabolic markers as differentially induced by antiretroviral therapies. We measured changes in markers of carbohydrate, of fat and bone metabolism, and, using dual-emission X-ray absorptiometry (DXA), body composition and bone mineral density (BMD). Complete data on changes between baseline and after 21 months treatment were available for 35 patients (16 in the PI group and 19 in the NNRTI group).

RESULTS

A significant gain in BMI and in total and lower limb fat mass was recorded only in patients receiving PI. A loss of lumbar BMD was observed in both groups, being higher with PI. Plasma markers of bone metabolism (alkaline phosphatase, osteocalcin, collagen crosslaps) and levels of parathormone and of 1,25diOH-vitamin D3 significantly increased in both groups, concomitant with a decline in 25OH-vitamin D3. Lipids and glucose levels increased in both groups but rise in triglyceride was more pronounced with PI. A correlation between loss of BMD and gain of fat mass is observed in patients starting PI.

CONCLUSIONS

We evidenced an early effect of ART on lipid and bone metabolisms. PI lead to a significant gain in fat mass correlated with a sharp drop in BMD but active bone remodelling is evident with all antiretroviral treatments, associated with low vitamin D levels and hyperparathyroidism. In parallel, signs of metabolic restoration are evident. However, early increases in lean and fat mass, triglycerides, waist circumference and leptin are much more pronounced with PI.

Metabolic complications and treatment of perinatally HIV-infected children and adolescents

The benefits of long-term antiretroviral therapy (ART) are recognized all over the world with infected children maturing into adults and HIV infection becoming a chronic illness. However, the improved survival is associated with serious metabolic complications, including lipodystrophy (LD), dyslipidemia, insulin resistance, lactic acidosis and bone loss. In addition, the dyslipidemia mainly seen with protease inhibitors may increase the risk of cardiovascular disease in adulthood and potentially in children as they mature into adults. Nucleoside reverse transcriptase inhibitors, particularly stavudine, zidovudine and didanosine are linked to development of LD and lactic acidosis. Perinatally infected children initiate ART early in life; they require lifelong therapy with multiple drug regimens leading to varying toxicities, all potentially impacting their quality of life. LD has a significant impact on the mental health of older children and adolescents leading to poor self-image, depression and subsequent poor adherence to therapy. Reduced bone mineral density (BMD) is reported in both adults and children on ART with the potential for children to develop more serious bone complications than adults due to their rapid growth spurts and puberty. The role of vitamin D in HIV-associated osteopenia and osteoporosis is not clear and needs further study. Most resource-limited settings are unable to monitor lipid profiles or BMD, exposing infected children and adolescents to on-going toxicities with unclear long-term consequences. Improved interventions are urgently needed to prevent and manage these metabolic complications. Longitudinal cohort studies in this area should remain a priority, particularly in resource-limited settings where the majority of infected children reside.

Bone and vitamin D metabolism in HIV

Human immunodeficiency virus (HIV) infection has progressed to a chronic disease and HIV positive individuals are living longer lives. This has lead to an increase in morbidity and mortality due to secondary issues, one being HIV bone disease. HIV infected pediatric and adult populations have a greater incidence in reduction of BMD as compared to the controls. Osteoporosis has been reported to be present in up to 15 % of HIV positive patients. We are starting to understand the mechanism behind the changes in HIV bone disease. Viral proteins interfere with osteoblastic activity either by direct interaction or by the inflammatory process that they induce. Anti-viral management, including highly active antiretroviral therapy (HAART), protease inhibitors, and nucleoside/nucleotide reverse transcriptase inhibitors (NRTI) also are involved in disrupting proper bone metabolism. Vitamin D levels have strong correlation with bone disease in HIV patients, and are dependent not only to chronic disease state, but interaction of pharmacologic management and inflammatory process as well. Work up of the secondary causes of osteopenia and osteoporosis should be undertaken in all patients. DEXA scan is recommended in all post-menopausal women with HIV, all HIV infected men 50 years of age or older and in those with a history of fragility fractures regardless of age or gender. Preventive measures include adequate nutrition, calcium and Vitamin D intake daily, muscle strengthening and balance exercises to increase BMD and reduce fractures. Bisphosphonates are considered to be the first line for the treatment of HIV associated bone disease. This review will describe how the balanced mechanism of bone metabolism is interrupted by the HIV infection itself, the complications that arise from HIV/AIDS, and its treatment options.

Factors associated with low bone mineral density in a Brazilian cohort of vertically HIV-infected adolescents

OBJECTIVE

To assess the prevalence and factors associated with low bone mineral density (BMD) in HIV-infected adolescents.

METHODS

This was a cross-sectional study of a Brazilian cohort of vertically HIV-infected adolescents. Body composition and lumbar spine (LS) and total body (TB) BMD were estimated by dual-energy X-ray absorptiometry (DXA). Low BMD was considered for a Z-score ≤-2 standard deviations. Pubertal development, anthropometric data, laboratory measurements, antiretroviral regimen, and time of immunological and virological recovery were evaluated as factors associated with a low BMD.

RESULTS

Seventy-four adolescents aged 17.3 ± 1.8 years were studied. Low BMD was present in 32.4% of them. LS and TB BMD Z-scores were positively correlated with weight, body mass index (BMI), BMI Z-score, total body fat, and nutritional status. Patients on tenofovir had lower LS and TB BMD Z-scores. Time on tenofovir was indirectly correlated with LS and TB BMD Z-scores. No difference was found regarding levels of calcium, parathyroid hormone, or 25-hydroxyvitamin D according to BMD status.

CONCLUSIONS

Control of the HIV infection, especially before the initiation of puberty, might have a positive influence on bone gain. Body composition and nutritional status had a positive influence on BMD that was more evident in females, suggesting that nutritional intervention may have a positive impact on BMD.

Bone effects of rosiglitazone in HIV-infected patients with lipoatrophy

OBJECTIVES

Thiazoledinediones increase limb fat in HIV+ patients with lipoatrophy. However, their use in the general population has been associated with bone loss and fracture. We sought to determine the effects of rosiglitazone on bone metabolism in HIV-infected patients.

METHODS

HIV+ patients with lipoatrophy were randomized to rosiglitazone versus placebo for 48 weeks in a double-blind, placebo-controlled trial. Limb fat, bone mineral density (BMD), bone formation markers (procollagen type 1 amino-terminal propeptide [P1NP], osteocalcin [OC]) and bone resorption markers (C-terminal telopeptide of type I collagen [CTX]) were measured, along with receptor activator for nuclear factor kappa β ligand (RANKL), osteoprotegerin (OPG), and inflammatory cytokines.

RESULTS

Seventy-one subjects were randomized to rosiglitazone or placebo: 17% female and 51% white. Total BMD did not change significantly in either group. In the rosiglitazone group, P1NP showed statistically significant decreases at 24 and 48 weeks; however, changes compared to placebo were only significant at 24 weeks. OC decreased significantly in the rosiglitazone group at 24 weeks, but there were no between-group differences. CTX, RANKL, or OPG did not change for either group. Multivariable regression within the rosiglitazone arm showed P1NP changes were inversely associated with limb fat changes, protease inhibitors, and tenofovir use.

CONCLUSION

Rosiglitazone use was associated with decreased bone formation, but it did not alter bone resorption or total BMD. The increase in limb fat that accompanies rosiglitazone use appears to be associated with decreased osteoblast activity. Further studies are needed to determine the effect of thiazoledinediones on bone health in HIV-infected persons.

Low bone mass in behaviorally HIV-infected young men on antiretroviral therapy: Adolescent Trials Network Study 021B

BACKGROUND

Peak bone mass is achieved in adolescence/early adulthood and is the key determinant of bone mass in adulthood. We evaluated the association of bone mass with human immunodeficiency virus (HIV) infection and antiretroviral therapy (ART) during this critical period among behaviorally HIV-infected young men and seronegative controls.

METHODS

HIV-positive men (N = 199) and HIV-negative controls (N = 53), ages 14-25 years, were studied at 15 Adolescent Trials Network for HIV/AIDS Interventions sites. HIV-positive participants were recruited on the basis of ART status: ART-naive (N = 105) or on a regimen containing a nonnucleoside reverse transcriptase inhibitor (NNRTI; N = 52) or protease inhibitor (PI; N = 42). Bone mineral density (BMD) and content (BMC) and body composition were measured by dual-energy X-ray absorptiometry (DXA). Results were compared across groups by linear modeling. Bone results were adjusted for race, body mass index (BMI), and type of DXA (Hologic/Lunar).

RESULTS

The HIV-positive and HIV-negative groups had comparable median age (21 years) and racial/ethnic distribution. Median times since HIV diagnosis were 1.3, 1.9, and 2.2 years in the ART-naive, NNRTI, and PI groups, respectively (P = .01). Total and regional fat were significantly lower in the ART-naive group compared with seronegative controls. Mean BMD and Z scores were generally lower among HIV-positive participants on ART, particularly in the PI group. Average Z scores for the spine were below zero in all 4 groups, including controls.

CONCLUSIONS

Young men on ART with a relatively recent diagnosis of HIV infection have lower bone mass than controls. Longitudinal studies are required to determine the impact of impaired accrual or actual loss of bone during adolescence on subsequent fracture risk.

A randomized study of tenofovir disoproxil fumarate in treatment-experienced HIV-1 infected adolescents

BACKGROUND

There are few data on the safety and antiviral activity of tenofovir disoproxil fumarate (TDF) in HIV-1 infected adolescents.

METHODS

A randomized, double-blinded, placebo-controlled study was conducted. Ninety adolescents (12 to <18 years) who were viremic while receiving antiretroviral treatment were randomized to receive TDF 300 mg (mean, 216.8 mg/m(2)) or placebo in combination with an optimized background regimen (OBR) for 48 weeks. The primary efficacy endpoint was time-weighted average change in plasma HIV-1 RNA from baseline at week 24

RESULTS

Eighty-seven subjects (45 TDF, 42 placebo) received the study drug. Through week 24, the median time-weighted average change in plasma HIV-1 RNA was not different between the TDF and placebo groups (-1.6 versus -1.6 log(10)copies/mL, P = 0.55). The percentages of subjects who achieved HIV-1 RNA <400 copies/mL were similar at week 24 (40.9 versus 41.5%). One fourth of subjects in the TDF and placebo groups (24.4 versus 28.6%) had at least 3 active agents in the OBR. Many subjects in both groups had baseline genotypic resistance to TDF (48.9 versus 33.3%). TDF was generally safe and well tolerated. There were no statistically significant differences in changes of renal function and bone mineral density between the 2 groups.

CONCLUSION

This study of TDF in combination with an OBR in antiretroviral-experienced adolescents did not meet its primary or secondary efficacy endpoints. The effectiveness of the OBR and baseline genotypic resistance to TDF in both groups may have confounded the efficacy findings. No clinically relevant TDF-related renal or bone toxicities were observed in this adolescent population.

Bone turnover, osteoprotegerin/RANKL and inflammation with antiretroviral initiation: tenofovir versus non-tenofovir regimens

BACKGROUND

Bone mineral density decreases with antiretroviral therapy (ART) initiation, although the pathogenesis, including the role of tenofovir (TDF), is unclear. This study assessed changes in bone-turnover markers, osteoprotegerin (OPG), soluble receptor activator for nuclear factor-κβ ligand (sRANKL), and inflammation in subjects initiating TDF- versus non-TDF-containing regimens, and determined the relationship between bone turnover, OPG/sRANKL and inflammation.

METHODS

This was a longitudinal observational study comparing levels of bone turnover markers (C-terminal telopeptide of type I collagen [CTX] and osteocalcin [OC]), OPG, sRANKL and inflammatory cytokines (soluble tumour necrosis factor [TNF]-α receptor [sTNFR]-I, sTNFR-II and interleukin-6) prior to ART and 6-12 months after ART initiation with a TDF- versus non-TDF-containing regimen in HIV-infected subjects 18-50 years old.

RESULTS

A total of 87 subjects were enrolled (TDF n=44 and non-TDF n=43). Groups were similar except subjects on TDF had a lower CD4(+) T-cell nadir (P<0.01) and were more likely to receive a protease inhibitor (PI; P=0.03). At pre-ART, 35% and 1% of subjects had CTX and OC above the normal range, respectively. Both increased with ART initiation, whereas OPG, sRANKL and inflammatory markers significantly decreased. In multivariate models, increases in OC were associated with TDF use, PI use and pre-ART levels of sTNFR-I, whereas increases in CTX were associated with CD4(+) T-cell nadir <50 cell/mm³. Increases in bone markers were unrelated to pre-ART levels of OPG/sRANKL and changes in OPG/sRANKL after ART initiation.

CONCLUSIONS

TDF use, PI use, TNF-α activity and advanced HIV disease are associated with changes in bone turnover markers, underscoring the complicated interaction between ART, bone turnover, inflammation and immune status, which extend beyond the OPG/RANKL system.

Effect of supplementation with cholecalciferol and calcium on 2-y bone mass accrual in HIV-infected children and adolescents: a randomized clinical trial

BACKGROUND

Skeletal abnormalities have been reported in HIV-infected children and adolescents. Although the etiology is not well understood, vitamin D deficiency may be involved.

OBJECTIVE

The study objective was to evaluate the effect of vitamin D and calcium supplementation on bone mass accrual in HIV-infected youth.

DESIGN

Perinatally HIV-infected children were randomly assigned to receive vitamin D (100,000 IU cholecalciferol given every 2 mo) and calcium (1 g/d) (supplemented group) or double placebo (placebo group) for 2 y. The total-body bone mineral content (TBBMC), total-body bone mineral density (TBBMD), spine bone mineral content (SBMC), and spine bone mineral density (SBMD) were assessed by using dual-energy X-ray absorptiometry at baseline and at 2 annual follow-up visits.

RESULTS

Fifty-nine participants, aged 6-16 y, were randomly assigned to either the supplemented (n = 30) or the placebo (n = 29) group. At enrollment, supplemented and placebo groups did not differ with respect to age, sex, dietary intakes of vitamin D and calcium, mean baseline serum 25-hydroxyvitamin D [25(OH)D] concentration, TBBMC, TBBMD, SBMC, or SBMD. Significant increases in serum 25(OH)D were observed in the supplemented group but not in the placebo group. TBBMC, TBBMD, SBMC, and SBMD increased significantly at 1 and 2 y in both groups. No between-group differences were observed at any time before or after adjustment for stage of sexual maturation by mixed linear model analysis.

CONCLUSION

One gram of calcium per day and oral cholecalciferol at a dosage of 100,000 IU every 2 mo administered to HIV-infected children and adolescents did not affect bone mass accrual despite significant increases in serum 25(OH)D concentrations. This trial was registered at clinicaltrials.gov as NCT00724178.

Exposure to antiretroviral agents during pregnancy does not alter bone status in infants

The use of combined antiretroviral agents during pregnancy is important to prevent mother-to-child transmission of human immunodeficiency virus (HIV). Antiretroviral treatment (ARV) is associated with reduced bone mass and altered bone metabolism in HIV-infected patients. There are no data regarding the effect of ARV exposure during pregnancy on newborns and infants. We therefore studied 38 subjects born from HIV-infected mothers, and we measured the speed-of-sound (SOS) at the tibia by quantitative ultrasonography (QUS) just after birth. QUS measurements at mid-tibia is easily performed in infants with the appropriate probe. Nevertheless, at this skeletal site only cortical bone is present, and therefore QUS measurements reflect the status of only one kind of bone tissue. We also measured bone alkaline phosphatase (BAP) and C-terminal telopeptide of type I collagen (CTX) in the cord blood as bone formation and resorption markers, respectively. SOS measurements were repeated at 4 and 12 months of age. As a control group we studied 94 subjects born from HIV-negative mothers. At birth the median (range) SOS of ARV-exposed neonates was 3006 (2870-3168) m/s, while that of control subjects was 3007 (2757-3311) m/s. The difference was not significant. BAP concentration of ARV-exposed was 103.6 (31.6-182.8) U/L, not different from that of control subjects (104.4 [43.2-227.2] U/L). CTX concentrations were 1.07 (0.26-2.8) ng/mL, and 1.38 (0.34-4.2) ng/mL in ARV-exposed and control subjects, respectively. SOS measurements at 4 months and 12 months of age were available for 17 ARV-exposed subjects and for 57 control subjects. SOS values changed significantly over time in both groups (F=6.1; P<0.0001). No differences were present between ARV-exposed and control subjects at 4 and 12 months. Our study suggests that ARV exposure during intrauterine life does not affect negatively bone metabolism and bone development, and that the changes occurring in bone QUS measurements during the first year of life in ARV-exposed subjects are similar to those occurring in healthy control infants.

Osteopenia and osteoporosis in people living with HIV: multiprofessional approach

Increasing bone mineralization abnormalities observed among people living with HIV (PLWHIV) result from various factors relating to the host, the virus, and the antiretrovirals used. Today, HIV infection is considered to be a risk factor for bone mineralization disorders. The test most recommended for diagnosing osteoporosis is measurement of bone mineral density by means of dual energy X-ray absorptiometry at two sites. Osteoporosis treatment has the aims of bone mass improvement and fracture control. A combination of calcium and vitamin D supplementation may reduce the risk of fractures. Antiresorptive drugs act by blocking osteoclastic activity and reducing bone remodeling. On the other hand, bone-forming drugs stimulate osteoblastogenesis, thereby stimulating the formation of bone matrix. Mixed-action medications are those that are capable of both stimulating bone formation and inhibiting reabsorption. Antiresorptive drugs form the group of medications with the greatest quantity of scientific evidence confirming their efficacy in osteoporosis treatment. Physical activity is a health promotion strategy for the general population, but only preliminary data on its real value and benefit among PLWHIV are available, especially in relation to osteoporosis.

Severe malnutrition and metabolic complications of HIV-infected children in the antiretroviral era: clinical care and management in resource-limited settings

More than 2 million children globally are living with HIV infection and >90% of these reside in sub-Saharan Africa. Severe acute malnutrition (SAM) remains a major problem for HIV-infected children who live in resource-limited settings (RLS), and SAM is an important risk factor for mortality. SAM in HIV-infected children is associated with complications including electrolyte disorders, micronutrient deficiencies, and severe infections, which contribute to the high mortality. Access to antiretroviral therapy (ART) has significantly improved the survival of HIV-infected children, although the response to ART of children with SAM remains undocumented in the literature. Immune and virologic responses to ART in RLS are similar to those of infected children in resource-rich settings, but delays in initiation of therapy have led to a high early mortality. Antiretroviral drug toxicities have been described in children who receive therapy and may affect their quality of life and long-term survival. Metabolic complications of ART include lipodystrophy, dyslipidemia, lactic acidosis, insulin resistance, and osteopenia. These complications have been well described in adults and children from developed countries, but data from RLS are limited, and these complications may be compounded by SAM. In this article we review the epidemiology, clinical presentation, and complications of SAM in HIV-infected children and the metabolic complications of HIV-infected children in the era of ART, and discuss future research priorities for RLS.

Vitamin D status in children and young adults with perinatally acquired HIV infection

BACKGROUND & AIMS

To assess vitamin D (Vit-D) [serum 25-hydroxyvitamin D (25-OHD) concentrations] in children and young adults with perinatally acquired HIV compared to geographically similar healthy children.

METHODS

25-OHD in children and young adults with HIV was compared to a healthy group. Vit-D deficiency and insufficiency were defined as 25-OHD <11 ng/mL and 25-OHD <30 ng/mL, respectively.

RESULTS

Children with HIV (n = 81), mean age 13.8 ± 4.1 years, 48% female, 83% Black, were compared to healthy subjects (n = 372), mean age 12.4 ± 3.4 years, 51% female, 37% Black. For the HIV group, 84% were on HAART, 54% had plasma HIV RNA <400 cpm, and 35% had moderate to severe immunosuppression (CD4+ count <500 cells/mm). Vit-D deficiency/insufficiency was present in 36% and 89% of those with HIV, and 15% and 84% of the comparison group, respectively. Vit-D deficiency was more prevalent in those with HIV (unadjusted odds ratio: 3.25; 95% CI: 1.9-5.5). For both groups, prevalence of Vit-D deficiency increased with age, BMI Z-score, Black race, and in winter/spring months. Vit-D deficiency was associated with a greater degree of immunosuppression in the subjects with HIV.

CONCLUSIONS

Vit-D deficiency was increased in subjects with perinatally acquired HIV and may be associated with disease severity.

Contraception in HIV-positive female adolescents

Sexual behavior of HIV-positive youths, whether infected perinatally, through risky behavior or other ways, is not substantially different from that of HIV-uninfected peers. Because of highly active antiretroviral therapy, increasing number of children, infected perinatally, are surviving into adolescence and are becoming sexually active and need reproductive health services. The objective of this article is to review the methods of contraception appropriate for HIV-positive adolescents with a special focus on hormonal contraceptives. Delaying the start of sexual life and the use of two methods thereafter, one of which is the male condom and the other a highly effective contraceptive method such as hormonal contraception or an intrauterine device, is currently the most effective option for those who desire simultaneous protection from both pregnancy and sexually transmitted diseases. Health care providers should be aware of the possible pharmacokinetic interactions between hormonal contraception and antiretrovirals. There is an urgent need for more information regarding metabolic outcomes of hormonal contraceptives, especially the effect of injectable progestins on bone metabolism, in HIV-positive adolescent girls.

Tenofovir disoproxil fumarate and bone mineral density: a 60-month longitudinal study in a cohort of HIV-infected youths

BACKGROUND

Decreased bone mineral density (BMD) has been associated with the use of tenofovir disoproxil fumarate (TDF) in HIV-infected adults. The data in HIV-infected children are conflicting. The aim of this study was to assess the safety of a TDF-containing antiretroviral (ARV) regimen on BMD in paediatric patients. We report the results of a longitudinal 60-month follow-up study.

METHODS

A total of 21 vertically HIV-infected Caucasian youths (10 male and 11 female) on ARV treatment containing lamivudine, efavirenz and TDF were enrolled (age range 4.9-17.9 years at baseline). BMD was measured at the lumbar spine and in the whole skeleton by DXA. Bone-specific alkaline phosphatase (BAP) was measured as a bone formation marker and urinary N-telopeptide of type-I collagen (NTx) was measured as a bone resorption index.

RESULTS

Baseline mean (±sd) BMD measurements of HIV-infected patients expressed as z-scores were -0.7 (±0.9) for lumbar spine and -0.13 (±1.0) for the whole skeleton. BMD measurements did not change significantly during the 60-month observation period. Both BAP and NTx concentrations were higher than a reference group of controls at baseline and remained unchanged throughout the study.

CONCLUSIONS

Our data indicate that a TDF-containing regimen does not decrease the BMD of HIV-infected youths.

Prospective study of renal function in HIV-infected pediatric patients receiving tenofovir-containing HAART regimens

AIM

to describe the impact of tenofovir disoproxil fumarate (TDF) use on renal function in HIV-infected pediatric patients.

DESIGN

it is a prospective, multicenter study. The setting consisted of five third-level pediatric hospitals in Spain. The study was conducted on patients aged 18 years and younger who had received TDF for at least 6 months. The intervention was based on the study of renal function parameters by urine and serum analyses. The main outcome measures were renal function results following at least 6 months of TDF therapy.

RESULTS

forty patients were included (32 were white and 26 were diagnosed with AIDS). Median (range) duration of TDF treatment was 77 months (16-143). There were no significant changes in the estimated creatinine clearance. Urine osmolality was abnormal in eight of 37 patients, a decrease in tubular phosphate absorption was documented in 28 of 38 patients, and 33 of 37 patients had proteinuria. A statistically significant decrease in serum phosphate and potassium concentrations was observed during treatment (P = 0.005 and P = 0.003, respectively), as well as a significant relationship between final phosphate concentration and tubular phosphate absorption (P = 0.010). A negative correlation was found between phosphate concentration and time on TDF.

CONCLUSIONS

TDF use showed a significant association with renal tubular dysfunction in HIV-infected pediatric patients. Periodic assessment of tubular function may be advisable in the follow-up of this population.

Bone disease in HIV infection: a practical review and recommendations for HIV care providers

Low bone mineral density (BMD) is prevalent in human immunodeficiency virus (HIV)-infected subjects. Initiation of antiretroviral therapy is associated with a 2%-6% decrease in BMD over the first 2 years, a decrease that is similar in magnitude to that sustained during the first 2 years of menopause. Recent studies have also described increased fracture rates in the HIV-infected population. The causes of low BMD in individuals with HIV infection appear to be multifactorial and likely represent a complex interaction between HIV infection, traditional osteoporosis risk factors, and antiretroviral-related factors. In this review, we make the point that HIV infection should be considered as a risk factor for bone disease. We recommend screening patients with fragility fractures, all HIV-infected post-menopausal women, and all HIV-infected men ⩾50 years of age. We also discuss the importance of considering secondary causes of osteoporosis. Finally, we discuss treatment of the more severe cases of bone disease, while outlining the caveats and gaps in our knowledge.

Antiretroviral therapy and bone mineral measurements in HIV-infected youths

Reduced bone mass measurements are often found in HIV-infected youths. Both in vitro and human studies demonstrated a role of antiretroviral treatment in determining bone mass alteration. Nevertheless, the data regarding the responsibility of different antiretroviral drugs on bone health in children and adolescents are highly controversial. The purpose of the current study was to relate antiretroviral treatment to bone mass measurements in a large cohort of HIV-infected children and adolescents. Bone mineral content (BMC) was measured in 86 HIV-infected youths (aged 4.8-22.1 years), and in 194 healthy controls (aged 4.9-21.9 years). Fifteen patients were naive to antiretroviral treatment, 11 were receiving a dual nucleoside reverse transcriptase inhibitor (NRTIs) combination, 32 a protease inhibitor (PI)-based antiretroviral treatment, and 28 a non-nucleoside reverse transcriptase inhibitor (NNRTIs)-based regimen. Comparisons between healthy and HIV-infected children and adolescents have been performed by multiple regression analyses to correct for differences in age, sex, and anthropometric measurements. Patients receiving a PI-based treatment had lumbar spine and whole body BMC values significantly lower than healthy children (P<0.05). BMC measurements of patients on other therapeutic regimens or naive to antiretroviral treatment did not differ significantly from those of healthy children. Among patients receiving a PI-based regimen, those receiving full dose Ritonavir had significantly lower lumbar spine BMC values compared to other patients. Lumbar spine and whole body BMC measurements of patients receiving a Stavudine-containing regimen were lower compared to healthy controls, naive patients, and patients on other antiretroviral regimens. Multivariate analyses showed that patients receiving both Stavudine and full dose Ritonavir had significantly lower BMC values both at the lumbar spine (P=0.0033), and in the whole skeleton (P=0.05). In conclusion, antiretroviral treatment may have a detrimental effect on bone health of HIV-infected youths: the use of Ritonavir full dose alone or in combination with Stavudine is associated to lower bone mass measurements. The use of antiretroviral regimens including these drugs should thus be monitored closely in HIV-infected youths.

Impact of antiretroviral therapy on growth, body composition and metabolism in pediatric HIV patients

Highly active antiretroviral therapy improves survival and growth in children with HIV infection. However, its use can be associated with adverse changes in body composition and metabolism. Bone mineral density can be adversely affected in HIV-positive children due to nutritional compromise or certain antiretrovirals. HIV-associated lipodystrophy, consisting of redistribution of adipose tissue, insulin resistance, and dyslipidemia, has also been described in children. Pediatric HIV patients may be at greater risk for these problems because of their longer potential lifetime exposure to these agents and because childhood is normally a period of rapid growth and tissue accretion. Healthcare providers for children with HIV infection must be aware of the potential complications associated with HIV antiretrovirals so that their antiviral efficacy can be balanced against their risk for side effects. In this review, we discuss the alterations in childhood growth and body composition that occur in HIV-infected children, and describe the impact of antiretroviral therapy on these outcomes. The problem of HIV-associated lipodystrophy syndrome in children is also discussed. Children with HIV should have their growth and body composition systematically monitored. Antiretroviral regimens should be tailored to optimize adherence and viral suppression while minimizing the potential for adverse side effects.

Growing up with HIV: children, adolescents, and young adults with perinatally acquired HIV infection

Tremendous success in the prevention and treatment of pediatric HIV in high-resource countries has changed the face of the epidemic. A perinatally HIV-infected child now faces a chronic disease rather than a progressive, fatal one. However, these successes pose new challenges as perinatally HIV-infected youth survive into adulthood. These include maintaining adherence to long-term, likely life-long therapy; selecting successive antiretroviral drug regimens, given the limited availability of pediatric formulations and the lack of pharmacokinetic and safety data in children; and overcoming extensive drug resistance in multi-drug-experienced children. Pediatric HIV care now focuses on morbidity related to long-term HIV infection and its treatment. Survival into adulthood of perinatally HIV-infected youth in high-resource countries encourages expansion of pediatric treatment programs in low-resource countries, where most HIV-infected children live, and provides important lessons about how the epidemic changes with increasing access to antiretroviral therapy for children.

Effect of bimonthly supplementation with oral cholecalciferol on serum 25-hydroxyvitamin D concentrations in HIV-infected children and adolescents

OBJECTIVE

Vitamin D insufficiency occurs commonly in HIV-infected youth in the United States. In light of the importance of vitamin D for skeletal and nonskeletal health, including innate immunity, developing methods for improving vitamin D status in HIV-infected children and adolescents is an important area of clinical research. The objective of this study was to evaluate the effect of administration of oral cholecalciferol, 100,000 IU every 2 months, and 1 g/day calcium on serum 25-hydroxyvitamin D concentrations, serum and urine calcium, and HIV disease progression during a 12-month period.

METHODS

HIV-infected children and adolescents who were aged 6 to 16 years were randomly assigned to receive vitamin D (100,000 IU bimonthly) and calcium (1 g/day; n = 29) or double placebo (n = 27). Serum 25-hydroxyvitamin D concentrations as measured by radioimmunoassay, albumin-corrected calcium concentrations, and spot urinary calcium-creatinine ratios were determined monthly.

RESULTS

No abnormalities in serum calcium concentration were observed. One participant who received placebo developed hypercalciuria. No group differences were seen in the change in CD4 count or CD4% or viral load during 12 months. The overall mean monthly serum 25-hydroxyvitamin D concentrations were higher in the group that received vitamin D and calcium than in the placebo group, as was the monthly serum 25-hydroxyvitamin D area under the curve. After completing 12 months of study, 2 (6.7%) participants in the group that received vitamin D and calcium had a trough serum 25-hydroxyvitamin D concentration <20 ng/mL compared with 14 (50%) in the placebo group. Twelve (44.4%) in the group that received vitamin D and calcium had a trough serum 25-hydroxyvitamin D concentration of > or =30 ng/mL compared with 3 (11.1%) in the placebo group.

CONCLUSIONS

Administration of oral cholecalciferol to HIV-infected children and adolescents at a dosage of 100,000 IU every 2 months, together with 1 g/day calcium, is safe and results in significant increases in serum 25-hydroxyvitamin D concentrations.

ORTHOPEDIC COMPLICATIONS IN HIV PATIENTS

The considerable increase of the life expectancy of HIV-infected patients in the age of highly-powerful antiretroviral treatment results in important metabolic and bone-joint changes resulting from a long-lasting viral infection time and from this treatment. The most common orthopaedic complications are bone mineralization changes, osteonecrosis, carpal tunnel syndrome and gleno-humeral adhesive capsulitis, with different clinical presentation features, natural disease progression and therapeutic response compared to the overall population. Literature reports are initial, and the experience of the multidisciplinary service of the University of Sao Paulo's Institute of Orthopaedics and Traumatology enables us a more indepth knowledge about the various pathologies involved and the development of treatment protocols that are appropriate to these diagnoses.

Long-term effects of highly active antiretroviral therapy on CD4+ cell evolution among children and adolescents infected with HIV: 5 years and counting

BACKGROUND

Lower percentages of CD4(+) T lymphocytes are associated with adverse clinical outcomes among children and adolescents infected with human immunodeficiency virus (HIV). CD4(+) lymphocyte percentage generally increases with receipt of highly active antiretroviral therapy (HAART), but long-term follow-up is required to assess whether these increases in CD4(+) cell percentage are maintained and whether they lead to normal CD4(+) cell percentages in children with severe immunosuppression.

METHODS

The study population included 1236 children and adolescents perinatally infected with HIV who were enrolled in a US-based multicenter prospective cohort study (Pediatric AIDS Clinical Trials Group 219/219C) and who were not receiving HAART at study initiation. We estimated the effects of HAART, HAART with protease inhibitors, and HAART with nonnucleoside reverse-transcriptase inhibitors on CD4(+) cell percentage, using marginal structural models to account for confounding by severity.

RESULTS

Initiation of any type of HAART increased CD4(+) cell percentage by 2.34% (95% confidence interval, 1.35%-3.33%) in the first year, relative to noninitiation of HAART. The substantial increases in CD4(+) cell percentage observed after the first year of experience with these combination therapies were followed by relatively smaller increases that continued for 5 years after initiation. Although larger increases in CD4(+) cell percentage were observed among children with a greater degree of immunosuppression at baseline, the mean CD4(+) cell percentage after 5 years of HAART did not reach normal levels.

CONCLUSIONS

Our study supports the initiation of HAART in children before severe immunosuppression occurs for long-term maintenance of normal CD4(+) cell percentages. This beneficial result must be weighed against the evidence of potential adverse events associated with the prolonged use of such therapy.

Metabolic complications of antiretroviral therapy in HIV-infected children

The purpose of this review is to describe the metabolic complications associated with antiretroviral therapy in HIV-infected children. As a result of extensive research over the last 10 years, there is a greater awareness and understanding of these conditions. However, in resource-limited settings, where the majority of HIV-infected children live, the prevalence and risk factors of metabolic complications are largely unknown. Limited diagnostic resources contribute to this impediment. Therapies for these conditions are still under investigation, including prevention and optimal treatment of reduced bone mineral density, osteopaenia and osteoporosis. Future research goals should be directed towards closing the diagnostic and treatment gaps between rich and poor settings.

Alterations in circulating osteoimmune factors may be responsible for high bone resorption rate in HIV-infected children and adolescents

OBJECTIVES

Bone metabolism derangements have been reported in HIV-infected children and adolescents. Nuclear factor kappa B ligand (RANKL) and osteoprotegerin potently stimulate and inhibit, respectively, osteoclast formation and activity. We investigated the possible role of RANKL and osteoprotegerin on bone metabolism alterations in paediatric patients.

DESIGN

A prospective controlled longitudinal study. Measurements were obtained before and 6 months after switching antiretroviral regimen.

METHODS

We studied 27 vertically HIV-infected children and adolescents (aged 4.9-17.3 years) on long-term HAART (70.1 +/- 1.5 months). All patients received lamivudine, stavudine and one protease inhibitor (PI). During follow-up, the PI was replaced with efavirenz and stavudine with tenofovir. We also enrolled 336 healthy children, aged 4.8-17.9 years. Concentrations of bone-specific alkaline phosphatase (BALP), N-terminal telopeptide of type I collagen (NTx), RANKL, and osteoprotegerin were measured at baseline and 6 months after switching.

RESULTS

BALP serum concentrations and NTx urine levels of HIV-infected patients were significantly higher than those of healthy children both at baseline and after 6 months (P < 0.001). Baseline osteoprotegerin and RANKL concentrations of HIV-infected patients were significantly higher than in healthy children (P < 0.0001). Both concentrations decreased after 6 months, and RANKL levels were no longer different to controls. At baseline the RANKL/osteoprotegerin ratio was significantly higher (P = 0.02) in HIV-infected children (0.27 +/- 0.07) compared with healthy children (0.078 +/- 0.01).

CONCLUSION

A marked alteration in the RANKL/osteoprotegerin system is present in patients receiving PI-based HAART. Short-term data indicate that replacing stavudine and PI with tenofovir and efavirenz restores the RANKL/osteoprotegerin equilibrium, and may thus lead to a reduction in the bone resorption rate.