Lipodystrophy in patients naive to HIV protease inhibitors

Specific Biological Features of Adipose Tissue, and Their Impact on HIV Persistence

Although white AT can contribute to anti-infectious immune responses, it can also be targeted and perturbed by pathogens. The AT's immune involvement is primarily due to strong pro-inflammatory responses (with both local and paracrine effects), and the large number of fat-resident macrophages. Adipocytes also exert direct antimicrobial responses. In recent years, it has been found that memory T cells accumulate in AT, where they provide efficient secondary responses against viral pathogens. These observations have prompted researchers to re-evaluate the links between obesity and susceptibility to infections. In contrast, AT serves as a reservoir for several persistence pathogens, such as human adenovirus Ad-36, Trypanosoma gondii, Mycobacterium tuberculosis, influenza A virus, and cytomegalovirus (CMV). The presence and persistence of bacterial DNA in AT has led to the concept of a tissue-specific microbiota. The unexpected coexistence of immune cells and pathogens within the specific AT environment is intriguing, and its impact on anti-infectious immune responses requires further evaluation. AT has been recently identified as a site of HIV persistence. In the context of HIV infection, AT is targeted by both the virus and the antiretroviral drugs. AT's intrinsic metabolic features, large overall mass, and wide distribution make it a major tissue reservoir, and one that may contribute to the pathophysiology of chronic HIV infections. Here, we review the immune, metabolic, viral, and pharmacological aspects that contribute to HIV persistence in AT. We also evaluate the respective impacts of both intrinsic and HIV-induced factors on AT's involvement as a viral reservoir. Lastly, we examine the potential consequences of HIV persistence on the metabolic and immune activities of AT.

Impact of HIV/simian immunodeficiency virus infection and viral proteins on adipose tissue fibrosis and adipogenesis

OBJECTIVE

HIV-infected patients receiving antiretroviral treatment (ART) often present adipose tissue accumulation and/or redistribution. adipose tissue has been shown to be an HIV/SIV reservoir and viral proteins as Tat or Nef can be released by infected immune cells and exert a bystander effect on adipocytes or precursors. Our aim was to demonstrate that SIV/HIV infection per se could alter adipose tissue structure and/or function.

DESIGN

Morphological and functional alterations of subcutaneous (SCAT) and visceral adipose tissue (VAT) were studied in SIV-infected macaques and HIV-infected ART-controlled patients. To analyze the effect of Tat or Nef, we used human adipose stem cells (ASCs) issued from healthy donors, and analyzed adipogenesis and extracellular matrix component production using two dimensional (2D) and three-dimensional (3D) culture models.

METHODS

Adipocyte size and index of fibrosis were determined on Sirius red-stained adipose tissue samples. Proliferating and adipocyte 2D-differentiating or 3D-differentiating ASCs were treated chronically with Tat or Nef. mRNA, protein expression and secretion were examined by RT-PCR, western-blot and ELISA.

RESULTS

SCAT and VAT from SIV-infected macaques displayed small adipocytes, decreased adipogenesis and severe fibrosis with collagen deposition. SCAT and VAT from HIV-infected ART-controlled patients presented similar alterations. In vitro, Tat and/or Nef induced a profibrotic phenotype in undifferentiated ASCs and altered adipogenesis and collagen production in adipocyte-differentiating ASCs.

CONCLUSION

We demonstrate here a specific role for HIV/SIV infection per se on adipose tissue fibrosis and adipogenesis, probably through the release of viral proteins, which could be involved in adipose tissue dysfunction contributing to cardiometabolic alterations of HIV-infected individuals.

The Lipodystrophy Syndrome in HIV-Infected Children under Antiretroviral Therapy: A First Report from the Central Africa

Background

Despite the high prevalence of the HIV/AIDS, few studies focused on the prevalence of lipodystrophy in pediatric HIV patients on antiretroviral therapy (ARV) in sub-Saharan African countries. The aim of this study was to assess the prevalence and to identify the risk factors of metabolic disorders related to ARV therapy in this population.

Methods

A cross-sectional study was completed in Kinshasa, the Democratic Republic of Congo. HIV-infected children aged between six and 18 years on ARV were consecutively recruited. For each case, two control children (one non-HIV infected child and one HIV-infected antiretroviral therapy-naïve child) were also recruited.

Results

80 HIV-infected on ARV therapy children (group 1), 80 noninfected children (group 2) and 65 HIV-infected antiretroviral therapy-naïve children (group 3) were recruited. The frequency of lipoatrophy was not statistically different between group 1 (16.3%) and group 3 (21.5%). A significantly higher proportion of lipohypertrophy, hypercholesterolemia, and lactic acidosis was noted in children of group 1, compared to the controls (p<0.05). Mixed form was rarely observed in this series. The frequency of hypertriglyceridemia was not different between the 3 groups (p>0.05).

Conclusion

Lipohypertrophy, hypercholesterolemia, and lactic acidosis emerge as a frequent metabolic disorders due to ARV therapy.

Treatment of dyslipidemia in HIV

Patients infected with HIV have a high risk of developing dyslipidemia. Effective therapeutic strategies can be challenging due to an increase risk of drug interactions and other comorbidities. Understanding the underlying pathophysiology and the principles of pharmacological and non-pharmacological therapeutic interventions can be of value in the appropriate management of dyslipidemia in the HIV-infected patient.

HIV-1 Vpr induces adipose dysfunction in vivo through reciprocal effects on PPAR/GR co-regulation

Viral infections, such as HIV, have been linked to obesity, but mechanistic evidence that they cause adipose dysfunction in vivo is lacking. We investigated a pathogenic role for the HIV-1 accessory protein viral protein R (Vpr), which can coactivate the glucocorticoid receptor (GR) and co-repress peroxisome proliferator-activated receptor γ (PPARγ) in vitro, in HIV-associated adipose dysfunction. Vpr circulated in the blood of most HIV-infected patients tested, including those on antiretroviral therapy (ART) with undetectable viral load. Vpr-mediated mechanisms were dissected in vivo using mouse models expressing the Vpr transgene in adipose tissues and liver (Vpr-Tg) or infused with synthetic Vpr. Both models demonstrated accelerated whole-body lipolysis, hyperglycemia and hypertriglyceridemia, and tissue-specific findings. Fat depots in these mice had diminished mass, macrophage infiltration, and blunted PPARγ target gene expression but increased GR target gene expression. In liver, we observed blunted PPARα target gene expression, steatosis with decreased adenosine monophosphate-activated protein kinase activity, and insulin resistance. Similar to human HIV-infected patients, Vpr circulated in the serum of Vpr-Tg mice. Vpr blocked differentiation in preadipocytes through cell cycle arrest, whereas in mature adipocytes, it increased lipolysis with reciprocally altered association of PPARγ and GR with their target promoters. These results delineate a distinct pathogenic sequence: Vpr, released from HIV-1 in tissue reservoirs after ART, can disrupt PPAR/GR co-regulation and cell cycle control to produce adipose dysfunction and hepatosteatosis. Confirmation of these mechanisms in HIV patients could lead to targeted treatment of the metabolic complications with Vpr inhibitors, GR antagonists, or PPARγ/PPARα agonists.

HIV-induced alteration in gut microbiota: driving factors, consequences, and effects of antiretroviral therapy

Consistent with an important role for adaptive immunity in modulating interactions between intestinal bacteria and host, dramatic alteration in the composition of gut microbes during chronic HIV infection was recently reported by ourselves and independently by four other research groups. Here we evaluate our results in the context of these other studies and delve into the effects of antiretroviral therapy (ART). Although gut microbiota of HIV-positive individuals on ART usually does not resemble that of HIV-negative individuals, the degree to which ART restores health-associated prevalence varies across bacterial taxa. Finally, we discuss potential drivers and health consequences of gut microbiota alterations. We propose that understanding the mechanism of HIV-associated gut microbiota changes will elucidate the role of adaptive immunity in shaping gut microbiota composition, and lay the foundation for therapeutics targeting the microbiota to attenuate HIV disease progression and reduce the risk of gut-linked disease in people with HIV.

Pharmacological management of cardiovascular conditions and diabetes in older adults with HIV infection

This review looks at the evidence for potential and theoretical risks of combining antiretroviral treatment with drugs prescribed for cardiovascular disease and diabetes. These conditions are common in the HIV-infected population as a result of ageing and the increased risk associated with both HIV infection and antiretroviral intake.

Alterations in the gut microbiota associated with HIV-1 infection

Understanding gut microbiota alterations associated with HIV infection and factors that drive these alterations may help explain gut-linked diseases prevalent with HIV. 16S rRNA sequencing of feces from HIV-infected individuals revealed that HIV infection is associated with highly characteristic gut community changes, and antiretroviral therapy does not consistently restore the microbiota to an HIV-negative state. Despite the chronic gut inflammation characteristic of HIV infection, the associated microbiota showed limited similarity with other inflammatory states and instead showed increased, rather than decreased, diversity. Meta-analysis revealed that the microbiota of HIV-infected individuals in the U.S. was most similar to a Prevotella-rich community composition typically observed in healthy individuals in agrarian cultures of Malawi and Venezuela and related to that of U.S. individuals with carbohydrate-rich, protein- and fat-poor diets. By evaluating innate and adaptive immune responses to lysates from bacteria that differ with HIV, we explore the functional drivers of these compositional differences.

Accelerated Aging in HIV Patients

Life expectancy has been increasing in the last few decades in the Western world and is accompanied by higher occurrence of age-related diseases like metabolic, cardiovascular, and renal diseases and also with a decline in immune functions. In HIV-infected people, due to the use of combination antiretroviral therapy (cART), life expectancy has increased. As a result, non-AIDS conditions which are age-associated have become more prevalent and appear earlier, resulting in accelerated aging in HIV patients. These non-AIDS conditions in HIV patients are associated with CD4+ T cell counts: lower counts are associated with higher rates of liver, cardiovascular, renal, and neurocognitive disorders. The effect of viral load and cART on the earlier occurrence of age-associated diseases is less significant than the CD4 count effect. Thus, the loss of immune functions in HIV-infected patients may enhance aging.

Body changes: antiretroviral therapy and lipodystrophy syndrome in people living with HIV/aids

OBJECTIVE: to identify the different types of morphological alterations from lipodystrophy syndrome (LS) in outpatients and relate them to the therapeutic regimen used. METHOD: a cross-sectional study which recruited 60 patients with HIV and LS and 79 without LS, who consented to interview and data collection from their medical notes. RESULTS: the region most affected by lipoatrophy was the face; by lipohypertrophy, the abdomen, and by the mixed form, the alterations to the abdomen, face, and upper and lower limbs. CONCLUSION: among the therapeutic regimens, that comprised of zidovudine, lamivudine and efavirenz seemed to protect against LS. Nursing can act in the early identification of the changes, as well as providing guidance and support for patients affected by the changes in their body image.

Biochemical Manifestation of HIV Lipodystrophy Syndrome

OBJECTIVES

Highly active anti-retroviral therapy (HAART), including protease inhibitors (PI) have led to dramatic improvements in the quality and quantity of life in patients with acquired immunodeficiency syndrome (AIDS). However, a significant number of AIDS patients on HAART develop characteristic changes in body fat redistribution referred to as lipodystrophy syndrome (LDS). Features of LDS include hypertrophy in the neck fat pad (buffalo hump), increased fat in the abdominal region (protease paunch), gynecomastia and loss of fat in the mid-face and extremities.

METHODS

The aim of this paper is to review the current knowledge regarding this syndrome. This article reviews the published investigations on biochemical manifestation of HIV lipodystrophy syndrome.

RESULTS

It is estimated that approximately 64% of patients treated with PI will experience this syndrome. Biochemically, these patients have increased triglycerides (Trig), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C) and extremely low high-density lipoprotein-cholesterol (HDL-C).

CONCLUSIONS AND PUBLIC HEALTH IMPLICATIONS

It is hoped that awareness of this syndrome would aid in early diagnosis and better patient management, possibly leading to a lower incidence of cardiovascular complications among these patients.

HIV and HAART-Associated Dyslipidemia

Effective highly active antiretroviral therapy (HAART) for human immunodeficiency virus-1 (HIV) infection has led to marked improvement in life-expectancy for those infected with HIV. Despite reductions in the incidence of AIDS with effective treatment, patients continue to experience considerable morbidity and mortality from non-AIDS illness such as premature cardiovascular disease, liver failure and renal failure. These morbidities, particularly premature cardiovascular disease, are thought to be related to a combination of the effects of an ageing HIV-infected population coupled with long-term effects of HIV infection and antiretroviral therapy (ART). One of the principle drivers behind the well documented increase in the risk of cardiovascular disease in HIV-infected patients is dyslipidemia.

This review will focus on the clinical presentation of HIV and ART-associated dyslipidemia, what is known of its patho-physiology, including associations with use of specific antiretroviral medications, and suggest screening and management strategies.

Treatment of dyslipidemia in HIV-infected patients

IMPORTANCE OF THE FIELD

Patients infected with HIV are at high risk for dyslipidemia, insulin resistance and cardiovascular disease. Therapies to reverse these risks are complex, sometimes controversial, and not uniformly effective.

AREAS COVERED IN THIS REVIEW

Pathophysiology of the lipid abnormalities in HIV is discussed, including the causes of alterations in triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and insulin resistance. We discuss the therapy of dyslipidemia in HIV using a combination of available clinical evidence and expert opinion based on extensive clinical experience, with discussions of lifestyle intervention and diet, conventional pharmacotherapy with lipid-lowering medications including statins, fibrates, niacin and thiazolidinediones for dyslipidemia, and newer therapeutic approaches including omega fatty acids, acipimox, growth hormone and leptin.

WHAT THE READER WILL GAIN

A detailed understanding of the pathophysiology and rational or evidence-based approach to therapy of lipid abnormalities in patients infected with HIV.

TAKE HOME MESSAGE

Treatment of dyslipidemia in patients with HIV is challenging and complicated by the risk of drug interactions. Appropriate therapy requires a sound understanding of pathophysiology and the principles of pharmacological and nonpharmacological therapeutic interventions. An evidence-based approach that combines lifestyle changes and drugs that are both safe and effective, singly and in combination, is described.

Association between HIV replication and serum leptin levels: an observational study of a cohort of HIV-1-infected South African women

Background

Advanced HIV infection can result in lipoatrophy and wasting, even in the absence of ongoing opportunistic infections, suggesting that HIV may directly affect adipose tissue amount and distribution.

Methods

We assessed the relationship of fat (measured using anthropometry, DEXA, MRI scans) or markers related to glucose and lipid metabolism with viral load in a cross-sectional sample of 83 antiretroviral-naïve HIV-1-infected South African women. A multivariable linear model was fitted to log₁₀VL to assess the combined effect of these variables.

Results

In addition to higher T cell activation, women with viral load greater than the population median had lower waist circumference, body mass index and subcutaneous abdominal fat, as well as lower serum leptin. We demonstrate that leptin serum levels are inversely associated with viral replication, independent of the amount of adipose tissue. This association is maintained after adjusting for multiple variables associated with disease progression (i.e., cellular activation and innate immunity effector levels).

Conclusions

Our results demonstrate that serum leptin levels are inversely associated with viral replication, independent of disease progression: we postulate that leptin may affect viral replication.

Interleukin-18 and interferon-gamma polymorphisms in Brazilian human immunodeficiency virus-1-infected patients presenting with lipodystrophy syndrome

Cytokines play important roles in the pathogenesis of lipodystrophy syndrome (LS). Single nucleotide polymorphisms (SNPs) at positions -607(C/A) and -137(C/G) in the promoter region of the interleukin-18 (IL-18) gene and at position +874(T/A) of the interferon-gamma (IFN-gamma) gene are related to the expression of these cytokines. To examine whether IL-18 and IFN-gamma polymorphisms are associated with LS, these SNPs were genotyped in 88 human immunodeficiency virus (HIV)-infected patients presenting LS, 79 HIV-infected without LS, and 133 healthy controls. The -607A allele, -607AA genotype, and -137G/-607A and -137C/-607A haplotypes in the IL-18 gene were over-represented in HIV patients presenting LS. The -137G/-607C haplotype was associated with protection against LS. These results indicate that the -607(C/A) SNP is associated with LS development in HIV-infected patients.

Prevalence and impact of body physical changes in HIV patients treated with highly active antiretroviral therapy: results from a study on patient and physician perceptions

Patients infected with HIV treated with highly active antiretroviral therapy (HAART) frequently develop body physical changes (BPC) that have an important psychosocial burden. The purpose of this study was to determine the prevalence of BPC observed by HIV-infected patients and their attending physicians and to assess the impact BPC had on daily life. In this epidemiologic multicenter study, patients with HIV infection and their treating physicians filled out parallel questionnaires about their perceptions of specific BPC and their impact on daily activities. A total of 965 patient-physician questionnaires were collected across 98 health centers. Patient's mean age was 43.7 +/- 8.5 years and 72.6% were men. Adjusted prevalence of perceived BPC by patients and physicians was 55.1% (95% confidence interval [CI]: 52.0-58.1) and 55.2% (95% CI: 52.1-58.2), respectively (p = 1.000). Overall patient-physician agreement concerning perception of BPC was 83% (p < 0.0005). The most common BPC was lipoatrophy, described by 46.8% (95% CI: 43.7-49.8) of patients and 49.4% (95% CI: 46.3-52.5) of physicians (p = 0.033) followed by lipohypertrophy. No gender differences were observed in the global prevalence of BPC (p = 0.649). However, significantly more women reported lipoatrophy of the lower limbs (p = 0.009) and buttocks (p = 0.007), as well as lipohypertrophy (p = 0.007), than men; 58.2% (95% CI: 54.0-62.4) patients noted that BPC negatively affected their daily activities. This study reflects the high prevalence of patient and physician-perceived BPC in the HIV population, and the adverse impact on daily life. Physicians should be aware of the psychosocial consequences of BPC in HIV patients in order to improve patient well-being.

The effect of individual antiretroviral drugs on body composition in HIV-infected persons initiating highly active antiretroviral therapy

OBJECTIVE

To examine the long-term effects of individual antiretroviral drugs on body composition among 416 persons initiating antiretroviral therapy (ART).

METHODS

In a substudy of a clinical trial of persons initiating ART, changes in body composition attributable to individual ART were examined. ARTs assessed were as follows: indinavir, ritonavir, nelfinavir, efavirenz, nevirapine, stavudine (d4T), zidovudine (ZDV), lamivudine (3TC), didanosine, and abacavir. Skinfolds and circumferences were measured at baseline and every 4 months. Mid arm, mid thigh, and waist subcutaneous tissue areas and nonsubcutaneous tissue areas were calculated. Rates of change per year of exposure to each individual ART drug were determined using multivariate longitudinal regression.

RESULTS

d4T and ZDV use was associated with losses in subcutaneous tissue area and skinfold thickness. 3TC use was associated with gains in all subcutaneous tissue areas and skinfold thickness, whereas abacavir use was associated with an increase in waist subcutaneous tissue area. Indinavir was associated with gains in waist subcutaneous tissue area, whereas indinavir, efavirenz, and nevirapine were associated with increases in upper back skinfolds. d4T use was also associated with increases in all nonsubcutaneous tissue areas; 3TC use was associated with the greatest increase in waist nonsubcutaneous tissue area.

CONCLUSION

In this prospective nonrandomized evaluation, the nucleoside reverse transcriptase inhibitors d4T and ZDV were associated with decreases in subcutaneous tissue areas, whereas 3TC use was associated with increased subcutaneous tissue areas and waist nonsubcutaneous tissue area.

Mitochondrial function, morphology and metabolic parameters improve after switching from stavudine to a tenofovir-containing regimen

OBJECTIVES

HIV-associated lipoatrophy has been associated with mitochondrial dysfunction induced by nucleoside reverse transcriptase inhibitor therapy. We hypothesize that lipid profiles and markers of mitochondrial function will improve in HIV-lipoatrophic patients switched to the nucleotide analogue tenofovir.

METHODS

Ten patients receiving stavudine, lamivudine and lopinavir/ritonavir (Kaletra(R)) for over 6 years were switched from stavudine to tenofovir for 48 weeks. Subcutaneous fat tissue biopsies, fasting metabolic tests, HIV RNA, CD4 cell count and whole body dual energy X-ray absorptiometry (DEXA) scans were obtained at study entry and week 48. Mitochondrial DNA (mtDNA) copies/cell and mitochondrial morphology were assessed in adipose tissue biopsies, mtDNA 8-oxo-deoxyguanine in peripheral blood mononuclear cells, and glutathione (GSH) and F2-isoprostane in plasma.

RESULTS

There was no change in limb fat mass by DEXA; however, trunk fat mass increased by 18.9% (P = 0.01). Fasting total cholesterol decreased by 33 mg/dL (P = 0.005) and serum glucose decreased by 4 mg/dL (P = 0.039). mtDNA copies/cell increased from 386 to 1537 (P < 0.001). Transmission electron microscopy showed that mitochondrial cristae were lacking or poorly defined at study entry, whereas mitochondrial inner structures were more well defined and outer membranes were intact at 48 weeks. Oxidative damage decreased in 8/10 patients, GSH increased and F2-isoprostane decreased.

CONCLUSIONS

The results from this study demonstrate that systemic and peripheral fat mitochondria improve in patients switched to tenofovir following long-term exposure to stavudine, while continuing protease inhibitor therapy.

Abordagem metabólica e nutricional da lipodistrofia em uso da terapia anti-retroviral

A terapia anti-retroviral altamente ativa, usada contra o Vírus da Imunodeficiência Humana, vem possibilitando a melhora do quadro clínico-laboratorial de portadores da Síndrome da Imunodeficiência Adquirida. Contudo, alterações metabólicas e complicações morfológicas, associadas ao uso da terapia, vêm sendo investigadas. A utilização prolongada desta terapia tem um impacto importante sobre o estado nutricional dos pacientes. Antes da sua utilização, a perda de peso e a desnutrição, conseqüências das infecções oportunistas, eram os maiores problemas nutricionais. Atualmente, o foco principal das discussões têm sido as complicações metabólicas e morfológicas, dentre elas a lipodistrofia, com a dislipidemia, a resistência à insulina, a osteopenia, e a distribuição alterada da gordura corporal, aumentando assim os riscos de doenças cardiovasculares. A nutrição desempenha um papel fundamental no suporte da saúde desses pacientes, integrando as equipes multiprofissionais, promovendo a melhora da adesão à terapia anti-retroviral e do prognóstico da doença. No entanto, para que se tenha mais conhecimento sobre a terapia, as proporções de seus efeitos adversos, e o perfil nutricional desses pacientes, a curto e a longo prazos, é de suma importância que se estude mais sobre este assunto, a fim de permitir perspectivas de um regime terapêutico mais seguro dentro de seus alcances metodológicos, proporcionando uma melhor qualidade de vida aos pacientes.

[Corporal fat distribution and lipidic and glicemic profiles of HIV-infected patients]

The aims of this study were to describe anthropometric data and glycemic and lipidic profiles of HIV-infected patients treated or not with antiretrovirals (ARV) drugs, and to assess association between these drugs and body composition changes, lipid and glucose homeostasis disturbances. There were 176 patients included (133 ARV-treated patients and 43 ARV-naïve). The patients were submitted to clinical evaluation, laboratorial analysis, ultrasonographic measurements, bioelectrical impedance analysis and skin folds thickness measurements. The ARV-treated group showed higher waist-to-hip ratio (p= 0.0002), higher intra-abdominal fat thickness measured by ultrasonography (p= 0.003) and lower bicipital (p= 0.01) and tricipital (p= 0.0002) skin folds. This group also showed higher triglyceride (p= 0.0002), total cholesterol (p= 0.00007), HDL cholesterol (p= 0.009), glucose measurements one hour (p= 0.01) and two hours (p= 0.001) after dextrose load, higher levels of fasting insulin (p= 0.03) and higher HOMAR index (p= 0.02). The antiretroviral drugs are associated with increased visceral fat and decreased peripheral fat pads. Beside that, these drugs are associated with atherogenic lipid profile and insulin resistance, two independent risk predictors of cardiovascular disease.

Experience in the treatment of HIV-associated lipodystrophy

AIM

To evaluate the outcome of patients with HIV-associated lipodystrophy treated within the Edinburgh unit to date.

METHODS

Information was collected from the medical case notes on the clinical features, method of treatment, postoperative complications, and length of follow up for each patient. A questionnaire was devised to assess patient satisfaction and facial volume was evaluated using three-dimensional imaging.

RESULTS

Forty-six patients with HIV-associated lipodystrophy were treated over a 3-year period. Twenty-six patients received Coleman fat injections, 10 patients were treated with Newfill, eight patients were treated with Bio-alcamid, 21 patients received liposuction, and three patients had a minimal access cranial suspension facelift. Follow up ranged from 1 to 14 months. Patient and surgeon satisfaction was high with autologous fat injections although fat resorption occurred in nine patients. Aesthetic improvement with Newfill was moderate and required up to seven treatment sessions. The results of treatment with Bio-alcamid were good immediately postoperatively, although two patients required further corrective procedures. Two patients who had liposuction to the dorso-cervical fat pad reported recurrence at 5 and 9 months, respectively.

CONCLUSIONS

Based on our experience, a treatment algorithm has been devised to aid management decisions. We favour the use of autologous fat injections for facial lipoatrophy but have found fillers to be useful in patients with inadequate fat reserves.

Impact of HIV infection on total body composition in treatment-naive men evaluated by dual-energy X-ray absorptiometry comparison of 90 untreated HIV-infected men to 241 controls

The aim of this study was to establish the contribution of human immunodeficiency virus (HIV) itself on body composition changes evaluated by dual-energy X-ray absorptiometry (DXA). Body composition evaluated by DXA in 90 HIV never treated men, without comorbidity, or current or past opportunistic infections were compared with 241 healthy volunteers. The mean duration of seropositivity from HIV diagnosis was 41+/-62 mo, mean CD4 and viral load at the time of DXA were 402/mm(3)+/-263 (control values 500-1200/mm(3)) and 4.2 log copies/mL+/-1.3. Mean age (41 vs 39 yr, respectively, for HIV never treated patients and controls) and mean height (174.5 vs 176 cm) were not different, but mean weight was lower among HIV never treated patients (69.8 vs 78.7 kg). Mean total body bone mineral density (BMD) of naive HIV-infected patients was lower than that of controls (1.20 vs 1.23 g/cm(2), p=0.01) but not after adjustment on age, height, lean mass (LM), and fat mass ratio (FMR=% trunk fat mass/% lower limb fat mass). Fat mass (13.2 vs 16.5 kg, p<0.0001) and LM (53.5 vs 59 kg, p<0.0001) of naive HIV-infected patients were lower whatever the adjustment variables. The FMR was lower in naive HIV-infected men (1.0 vs 1.3, p<0.0001) because of a decreased trunk fat mass. After adjustment on age, height, LM, and fat mass, the lower limbs fat mass percentage was higher in HIV-infected men. The profile of naïve HIV-infected patients displayed low lean and fat masses, and a fat mass repartition characterized by a predominant loss in the trunk. Those alterations may result from the catabolic effect of the chronic HIV infection.

Increased serum lipids are associated with higher CD4 lymphocyte count in HIV-infected women

OBJECTIVE

Highly active antiretroviral therapy (HAART) has been associated with dyslipidaemia; however, the roles of immune status and non-HIV-disease risk factors remain unclear.

METHODS

A cross-sectional analysis of fasting lipids was carried out for 231 women, of whom 132 were HIV-infected and 99 were uninfected. The concentrations of total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides, and apolipoprotein B (apo B) were measured. CD4 lymphocyte count, hepatitis C status, demographics, diet, and anthropometrics were also assessed.

RESULTS

A total of 132 women were HIV-infected [30 were antiretroviral-naive, 68 were on protease inhibitors (PIs), and 34 were on non-PI HAART]. HIV infection was associated with higher triglycerides, lower HDL-C, and, among obese women, higher total cholesterol and LDL-C. Non-PI and PI HAART were each independently associated with higher total cholesterol, LDL-C, and apo B, compared with being ART-naive. Among HIV-infected women, after adjustment for HAART use, women with a CD4 lymphocyte count > or =500 cells/microL had total cholesterol 41.8 mg/dL (P = 0.002) and LDL-C 28.8 mg/dL (P = 0.01) higher, on average, than women with a CD4 count <200 cells/microL. Women with a CD4 count of 200-499 cells/microL had total cholesterol 26.31 mg/dL higher, on average, than those with a CD4 count <200 cells/microL (P = 0.04), although differences in LDL-C did not reach significance (15.51 mg/dL; P = 0.12). A higher CD4 count was also associated with higher apo B (P < 0.001). Active hepatitis C infection was associated with lower total cholesterol, LDL-C, triglycerides, and apo B.

CONCLUSIONS

Higher CD4 lymphocyte counts were associated with higher lipid levels, suggesting that immune competence may independently affect the dyslipidaemia seen in the HAART era. In addition, it is important that hepatitis C status be assessed in studies of dyslipidaemia in the HIV-infected population.

Antiretroviral therapies associated with lipoatrophy in HIV-infected women

We previously demonstrated that HIV infection is associated with peripheral and central lipoatrophy in women. We now describe the association of specific antiretroviral drugs (ARV) with body fat changes over a four-year period from 1999 to 2003. 775 HIV-positive and 205 HIV-negative women in the Women's Interagency HIV Study with anthropometric measurements, weight, bioelectric impedance analysis and ARV collected semiannually were included in analysis. Exposure to ARV was defined as report of use for 3 consecutive semiannual study visits. The average 6-month change in weight, percent total body fat, and circumference measurements (i.e., hip, waist, chest, arm, and thigh) was compared between those exposed and those unexposed to the specific ARV for any of the same three consecutive visits. Weight, percent total body fat, and hip, waist, thigh, chest, and arm circumferences decreased in HIV-positive women, but increased in HIV-negative women on average for every six-month interval over the 4-year study period. Among the HIV-positive women, didanosine was the only ARV associated with decreases in circumference measures in the hip (-0.65 cm, 95% confidence interval [CI]: -1.18, -0.12), waist (-0.71 cm, 95% CI: -1.37, -0.04), chest (-0.71 cm, 95% CI: -1.17, -0.26), and arm (-0.23 cm, 95% CI: -0.48, 0.03; p = 0.08). These prospective data suggest that fat loss continues to predominate in HIV-positive women and exposure to didanosine for at least 12 months may further worsen fat loss.

Tratamiento antirretroviral y toxicidad mitocondrial

The introduction of highly active antiretroviral therapy for the treatment of human immunodeficiency virus (HIV) infection has led to substantial reduction in morbidity and near-complete suppression of HIV-1 replication. This progress has been tempered by a growing number of new adverse effects. Mitochondrial toxicity is one aspect of these long-term toxicities of antiretroviral drugs, with the role of nucleoside analogs being particularly underlined. Some cases of impaired mitochondrial function have been clearly identified, such as pancreatitis, neuropathy, miopathy and lactic acidosis. Beyond the inhibition of DNA polymerase-g using nucleoside analogs, it appears that several physiopathologic mechanisms interact to explain the observed toxicity. At present there is no reliable method to detect subclinical mitochondrial toxicity. There is no proven effective therapy for antiretroviral therapy-associated mitochondrial toxicity other than ceasing the implicated agent, and even with this strategy, resolution of symptoms may be incomplete. Therefore, investigation of mitochondrial toxicity of new compounds or new combinations is of growing interest for the clinical application of antiretroviral agents.

Minocycline- and tetracycline-induced hypertriglyceridemia in an HIV-seropositive patient receiving combination antiretroviral therapy

BACKGROUND

Acne vulgaris may occur as part of immune reconstitution in human immunodeficiency virus (HIV)-seropositive patients on highly active antiretroviral therapy (HAART). Tetracyclines are a common acne treatment. Hypertriglyceridemia has not been reported as a side effect of this drug class.

OBJECTIVE

We report a case of an HIV-seropositive man on HAART (CD4 count 450 cells/microL) who developed isolated hypertriglyceridemia (> 13 mmol/L) after three separate challenges with minocycline or tetracycline, improving each time therapy was discontinued.

RESULTS

Based on a review of the literature, this is the first reported case of hypertriglyceridemia with minocycline or tetracycline therapy. No published reports have examined the safety of tetracyclines in the setting of HIV or HAART.

CONCLUSION

A strong temporal association between tetracycline use and hypertriglyceridemia was found without an alternate explanation for the observed lipid profile. Given the common use of tetracyclines in dermatology, we feel that this is an important observation to report.

Effects of protease inhibitors on glucose tolerance, lipid metabolism, and body composition in children and adolescents infected with human immunodeficiency virus

OBJECTIVE

To evaluate the effects of protease inhibitors (PIs) as antiretroviral therapy in comparison with other antiretroviral (non-PI) medications on glucose tolerance, lipid metabolism, and body fat distribution in human immunodeficiency virus (HIV)-infected young patients.

METHODS

We conducted a cross-sectional clinical study in an outpatient HIV clinic. The study population consisted of 21 patients (15 female and 6 male) who had had at least 6 months of antiretroviral treatment. The mean age of the patients was 11.9 years (range, 6 to 16.5).

RESULTS

Fifteen patients treated with PIs and 6 patients treated with non-PIs were enrolled in the study. We found no significant differences in the lipid panel and insulin resistance, as determined by using the Quantitative Insulin Sensitivity Check Index formula, in the PI group in comparison with the non-PI group. Lipodystrophy was observed in 47% (7 of 15) of the PI group and 33% (2 of 6) of the non-PI group (P = 0.66). In the presence of lipodystrophy, serum triglyceride levels were higher in the PI group than in the non-PI group (P = 0.046). No such difference was found between the treatment groups when no lipodystrophy was present. There was no significant difference in insulin resistance between the treatment groups in the presence or absence of lipodystrophy.

CONCLUSION

Our study found the presence of lipodystrophy in HIV-infected young patients regardless of whether they were taking PIs or not. In the patients who had lipodystrophy, those treated with PIs had higher serum triglyceride levels than those not treated with PIs.

Fat distribution in women with HIV infection

OBJECTIVE

Both peripheral fat loss and central fat gain have been reported in women with HIV infection. We determined the fat changes that are specific to HIV infection in women.

METHODS

HIV-infected and control women from the study of Fat Redistribution and Metabolic Change in HIV Infection (FRAM) were compared. Lipoatrophy or lipohypertrophy was defined as concordance between participant report of fat change and clinical examination. Whole-body magnetic resonance imaging measured regional adipose tissue volumes. The relationship among different adipose tissue depots was assessed. Factors associated with individual depots were analyzed using multivariate linear regression.

RESULTS

HIV-infected women reported more fat loss than controls in all peripheral and most central depots. Peripheral lipoatrophy was more frequent in HIV-infected women than controls (28% vs. 4%, P < 0.001), whereas central lipohypertrophy was similar (62% vs. 63%). Among HIV-infected women, those with central lipohypertrophy were less likely to have peripheral lipoatrophy (odds ratio, 0.39; 95% confidence interval, 0.20 to 0.75, P = 0.006) than those without central lipohypertrophy. On magnetic resonance imaging, HIV-infected women with clinical peripheral lipoatrophy had less subcutaneous adipose tissue (SAT) in peripheral and central sites and less visceral adipose tissue (VAT) than HIV-infected women without peripheral lipoatrophy. Compared with controls, HIV-infected women had less SAT in the legs, regardless of the presence or absence of lipoatrophy. However, those without lipoatrophy had more VAT and upper trunk SAT than controls. Use of the antiretroviral drug stavudine was associated with less leg SAT but was not associated with VAT. The use of highly active antiretroviral therapy, however, was associated with more VAT.

CONCLUSIONS

Peripheral lipoatrophy occurs commonly in HIV-infected women but is not associated with reciprocally increased VAT or trunk fat.

Serum adiponectin and leptin concentrations in HIV-infected children with fat redistribution syndrome

Human immunodeficiency virus (HIV)-related lipodystrophy is characterized by adipose tissue redistribution, dyslipidemia, and insulin resistance. We hypothesized that fat redistribution and metabolic abnormalities in HIV-infected children are related to alterations in endocrine function of adipose tissue. A multicenter study was conducted in 130 HIV-infected children. Lipodystrophy definition was based on the central to peripheral skinfold ratio. Fasting adiponectin, leptin, insulin concentrations, glycemia, and lipid profile were measured in all children. Fat redistribution syndrome was apparent in 32 children: 14 with atrophic (LPDA) and 18 with hypertrophic lipodystrophy (LPDH). Mean serum adiponectin levels were significantly decreased in LPDA and LPDH groups compared with the group with no lipodystrophy (LPD-). Fasting insulin concentration was significantly higher in LPDA and LPDH groups versus LPD-. Mean serum leptin concentration was significantly increased only in LPDH compared with LPDA and LPD- groups. Triglyceride levels were significantly increased and high-density lipoprotein (HDL)-cholesterol concentration decreased in the LPDA versus LPD- group. Controlling for puberty stage, gender, percentage of total fat mass, serum lipids, HIV treatment, and disease severity, adiponectin was significantly and inversely associated with central obesity and insulin/glucose ratio. Fat redistribution had no significant effect on leptin concentration, which was directly related to the percentage of body fat, female gender, and insulin/glucose ratio. In conclusion, HIV-infected children with symptoms of fat redistribution have decreased levels of adiponectin, associated with insulin resistance and dyslipidemia.

The study of fat redistribution and metabolic change in HIV infection (FRAM): methods, design, and sample characteristics

The Study of Fat Redistribution and Metabolic Change in HIV Infection (FRAM), initiated in 2000, investigates the prevalence and correlates of changes in fat distribution, insulin resistance, and dyslipidemia among human immunodeficiency virus (HIV)-infected men and women compared with a population-based group of control men and women. Between June 2000 and September 2002, 1,480 participants (1,183 HIV-infected persons and 297 controls) were enrolled in FRAM. Measurements taken included whole-body magnetic resonance imaging for quantification of regional fat, anthropometric measurements, central laboratory analysis of metabolites, and assessment of symptoms, sociodemographic factors, and lifestyle. Similar measurements were repeated among FRAM participants 4 years later (FRAM 2) for investigation of the progression of fat distribution changes, insulin resistance, and hyperlipidemia. In FRAM 2, which is ongoing, investigators are also determining the associations of subclinical cardiovascular disease, as measured by carotid intimal-medial wall thickness, with HIV infection, fat distribution changes, insulin resistance, and other proatherogenic changes in serum lipid levels. The demographic characteristics of HIV-infected FRAM men and women were comparable to those reported from a national random sampling of HIV-infected men and women receiving medical care in the United States. The representativeness of the FRAM sample increases its value as a resource for studies on fat distribution, metabolic changes, and atherosclerosis in HIV infection.

[Metabolic alterations in HIV-associated lipodystrophy syndrome]

The introduction of highly active antiretroviral therapy (HAART) has reduced morbidity and mortality in patients infected with the human immunodeficiency virus (HIV). However, prolonged treatment with combination regimens can be difficult to sustain because of problems with adherence and toxic effects. Treatment with antiretroviral agents--protease inhibitors in particular--has uncovered a syndrome of abnormal fat redistribution, impaired glucose metabolism, insulin resistance and dyslipidemia, collectively termed lipodystrophy syndrome (SLHIV). Nowadays, no clinical guidelines are available for the prevention or treatment of SLHIV, and its cause have yet to be totally elucidated. This review emphasizes the clinical features and the data from previous studies about the SLHIV taking into account that a better understanding of this syndrome for HIV specialists, cardiologists and endocrinologists is fundamental for the disease control.

Antiretroviral-therapy-associated lipoatrophy: current status and future directions

Lipoatrophy is perhaps the most visibly recognisable component of antiretroviral-therapy-associated lipodystrophy due to the rarity of this form of body composition change in the general population. In this respect, it is apparent that lipoatrophy represents a form of drug toxicity specifically involving the subcutaneous fat tissue, resulting in pathological fat loss that preferentially affects the limbs and face. It is now clear that the choice and duration of nucleoside analogue reverse transcriptase inhibitor (NRTI) therapy (stavudine > zidovudine) is the dominant risk factor for clinical lipoatrophy, as well as for the pathological changes to adipose tissue that underlie the clinical syndrome. Host factors have also emerged as important modulators of lipoatrophy severity in patients receiving these NRTI drugs, including age, racial origin, and severity of immune deficiency. On the other hand, the use of selected HIV protease inhibitor drugs is more closely associated with metabolic complications such as dyslipidemia and insulin resistance and has not been convincingly linked to lipoatrophy. This review examines the clinical and pathological manifestations of lipoatrophy, and also presents information regarding the safety profile of alternative NRTI drugs, such as tenofovir and abacavir, that have not been associated with lipoatrophy risk. With increasing knowledge of lipoatrophy pathogenesis, it is likely that moderate and severe forms of this complication can now be considered a preventable complication of HIV treatment. However, it is also important to recognise that there is an ongoing burden of disease in patients who have been affected by lipoatrophy over the past six years, and that therapeutic management of established lipoatrophy will remain a challenge into the future.

Adverse effects of antiretroviral therapy for HIV infection: a review of selected topics

In the current era of HIV treatment, the toxicity profiles of antiretroviral drugs have increasingly emerged as a basis for selecting initial antiretroviral regimens as well as a reason for switching therapy in treatment-experienced patients. In this respect, an intensive research effort involving clinical research as well as basic science research over the past six years, has focused on the cluster of metabolic and body composition abnormalities that have come to be termed the 'lipodystrophy syndrome'. These data have now provided a clear and clinically relevant understanding of the individual profiles of drugs within the nucleoside analogue reverse transcriptase inhibitor , HIV protease inhibitor and non-nucleoside analogue reverse transcriptase inhibitor drug classes, and have provided a rational basis for assessing and monitoring these adverse effects in clinical practice. In this review, current and emerging drug toxicities are considered with an emphasis on lipodystrophy complications.

Fat distribution in men with HIV infection

OBJECTIVE

Both peripheral fat loss and central fat gain have been reported in HIV infection. Which changes are specific to HIV were determined by comparison with control subjects and the associations among different adipose tissue depots were determined.

METHODS

Cross-sectional analysis of HIV-positive and control men from the study of Fat Redistribution and Metabolic Change in HIV Infection. Lipoatrophy or lipohypertrophy was defined as concordance between participant report of change and examination. Regional adipose tissue volume was measured by magnetic resonance imaging (MRI).

RESULTS

HIV-positive men reported more fat loss than controls in all peripheral and most central depots. Peripheral lipoatrophy was more frequent in HIV-positive men than in controls (38.3% vs. 4.6%, P < 0.001), whereas central lipohypertrophy was less frequent (40.2% vs. 55.9%, P = 0.001). Among HIV-positive men, the presence of central lipohypertrophy was not positively associated with peripheral lipoatrophy (odds ratio = 0.71, CI: 0.47 to 1.06, P = 0.10). On MRI, HIV-positive men with clinical peripheral lipoatrophy had less subcutaneous adipose tissue (SAT) in peripheral and central sites and less visceral adipose tissue (VAT) than HIV-positive men without peripheral lipoatrophy. HIV-positive men both with and without lipoatrophy had less SAT than controls, with legs and lower trunk more affected than upper trunk. Use of the antiretroviral drugs stavudine or indinavir was associated with less leg SAT but did not appear to be associated with more VAT; nevirapine use was associated with less VAT.

CONCLUSION

Both peripheral and central subcutaneous lipoatrophy was found in HIV infection. Lipoatrophy in HIV-positive men is not associated with reciprocally increased VAT.

Tolerability and safety of HIV protease inhibitors in adults

Antiretroviral drugs are associated with both short-term and long-term adverse events. Like other HIV drugs, protease inhibitors (PIs) may affect metabolic processes influencing body shape and body tissue composition, appearance, bone integrity, and cardiovascular status. However, numerous confounding variables including age, cigarette smoking, body mass index (BMI), duration of HIV infection, degree of immunodeficiency, concomitant antiretroviral agents, extent of previous treatment, and duration of treatment all blur the relationship between PI use and adverse events. Recent data suggest that the early PIs appear to have greater effects on such surrogate markers of disease risk as insulin resistance and cholesterol and triglyceride levels than the recently developed PIs. These data also suggest that evaluation of PIs as a class should be reconsidered and that it is probably not appropriate to extrapolate safety data obtained from individuals treated with first-generation agents in the era of potent combination antiretroviral therapy to those treated with recently developed PIs. Because PIs remain a critical component of successful antiretroviral therapy, evaluation of potential long-term complications with prolonged PI use is essential, as is delineation of the significant differences in safety profiles among individual PIs.

A post-processing method for multiexponential spin–spin relaxation analysis of MRI signals

Quantitative MR imaging is a potential tool for tissue characterization; in particular, proton density and proton relaxation times can be derived from MR signal analysis. However, MR image noise affects the accuracy of measurements and the number of tissue parameters that can be reliably estimated. Filtering can be used to limit image noise; however this reduces spatial resolution. In this work we studied, using both simulations and experiments, a filter called a 'selective blurring filter'. Compared to other classical filters, this filter achieves the best compromise between spatial resolution and noise reduction. The filter was specifically used to reliably determine the bi-component transverse relaxation of protons in adipose tissue. Long and short relaxation times and the relative proton fraction of each component were obtained with a degree of uncertainty of less than 10% and an accuracy of 95%.

Patient characteristics and costs associated with dyslipidaemia and related conditions in HIV-infected patients: a retrospective cohort study

BACKGROUND

Metabolic abnormalities are common in HIV-infected individuals and, although multifactorial in origin, have been strongly associated with antiretroviral therapy.

METHODS

Using automated claims and clinical databases, combined with medical record data, we evaluated the burden of dyslipidaemia (DYS) and associated metabolic abnormalities among a cohort of 900 HIV-infected patients aged 18 years and older who received their care from a large multispecialty medical group between 1 January 1996 and 30 June 2002. A Cox proportional hazards model for DYS was developed. Resource use was compiled and subsequently costed with stratification to account for variable length of follow-up.

RESULTS

Mean follow-up time was 3.3 years. DYS was present in 54% of the cohort and 3.4% experienced a cardiovascular (CV) event. Both unadjusted and adjusted results found patients with dyslipidaemia and cardiovascular events significantly more likely to have received protease inhibitor (PI) treatment for longer periods of time. In the Cox proportional hazards model the following factors were significantly associated with an increased risk for DYS: older age, white race, PI use and male sex. Diagnoses of hypertension, hepatitis C virus infection, depression or opportunistic infections were all negatively associated with a DYS diagnosis. When controlled for length of follow up, patients with DYS (and no CV-related events) incurred greater median and mean total average costs than patients without DYS or CV-related events. For patients with more than 2 years of follow up, these total cost differences were statistically significant (P<0.05).

CONCLUSIONS

These findings indicate that DYS is common among patients with HIV infection and is associated with increased use of medical resources.

Adverse effects of antiretroviral therapy for HIV infection: a review of selected topics

In the current era of HIV treatment, the toxicity profiles of antiretroviral drugs have increasingly emerged as a basis for selecting initial antiretroviral regimens as well as a reason for switching therapy in treatment-experienced patients. In this respect, an intensive research effort involving clinical research as well as basic science research over the past six years, has focused on the cluster of metabolic and body composition abnormalities that have come to be termed the 'lipodystrophy syndrome'. These data have now provided a clear and clinically relevant understanding of the individual profiles of drugs within the nucleoside analogue reverse transcriptase inhibitor , HIV protease inhibitor and non-nucleoside analogue reverse transcriptase inhibitor drug classes, and have provided a rational basis for assessing and monitoring these adverse effects in clinical practice. In this review, current and emerging drug toxicities are considered with an emphasis on lipodystrophy complications.

Total body composition by DXA of 241 HIV-negative men and 162 HIV-infected men: proposal of reference values for defining lipodystrophy

The aim of this study was to define standard values for fat mass distribution by dual-energy X-ray absorptiometry in human immunodeficiency virus (HIV)-negative men and to analyze factors associated with lipodystrophy in HIV-infected men. Total-body composition was analyzed in 241 HIV-negative men (controls) and 162 HIV-infected men. We created a fat mass ratio (FMR) as the ratio of the percentage of the trunk fat mass to the percentage of the lower limbs fat mass. We defined the FMR standard values as the mean value+/-standard deviation. We compared body mass index (BMI), fat mass percentage (%FM), lean mass (LM), bone mineral density (BMD), and FMR between the control group and HIV-infected men, by age range, according to prescription of treatment and presence of clinical lipodystrophy. The FMR standard value is equal to 1.3+/-0.2. The FMR was higher in treated HIV-infected men with or without clinical lipodystrophy. The FMR was similar for naïve HIV-infected men and controls. It was positively correlated with age, cumulative time on treatment, zidovudine, stavudine, or indinavir. BMD and fat mass were lower for treated and naïve HIV-infected men than for HIV-negative men. The FMR seems to be a valuable index for measuring fat mass distribution. We defined FMR standard values from the largest group of HIV-negative men to our knowledge. Applying FMR to HIV patients could help physicians to diagnose lipodystrophy earlier.

Lipodystrophy Syndrome: The Morphologic and Metabolic Effects of Antiretroviral Therapy in HIV Infection

Widespread use of highly active antiretroviral therapy (HAART) to manage HIV infection is now associated with the development of lipodystrophy syndrome. This syndrome is a combination of such morphologic and metabolic changes as hyperlipidemia, fat redistribution, and insulin resistance. Although many of the long-term effects of HAART have not been fully recognized, it is thought that lipodystrophy syndrome may now contribute to early-onset hypercholesterolemia, heart disease, and diabetes, and may have a negative psychological impact on the individual living with HIV infection.

Complications Associated with Nrti Therapy: Update on Clinical Features and Possible Pathogenic Mechanisms

The availability of durable, effective antiretroviral therapy for HIV-infected patients has fundamentally altered the prognosis of this disease and has also increased awareness that long-term drug toxicities have the potential to cause significant morbidity and even mortality in this patient population. The long-term use of nucleoside analogue reverse transcriptase inhibitor (NRTI) drugs has been associated with a number of clinically relevant toxicities including hyperlactataemia and lactic acidosis, neuropathy, pancreatitis and, more recently, a syndrome of pathological loss of subcutaneous fat tissue (lipoatrophy). Importantly, the toxicity profile of each NRTI drug within this class is unique in terms of the overall risk of long-term complications, as well as the tissue specificity of its toxic effects. In this review, the clinical manifestations, risk factors and pathological basis for NRTI-associated toxicity syndromes are explored, with an emphasis on clinical assessment and management.

Lipodystrophies: rare disorders causing metabolic syndrome

Recent advances in the understanding of the molecular basis of genetic lipodystrophies have promoted understanding of how adipose tissue disorders can cause the metabolic syndrome and its complications. These discoveries hold promise for elucidating pathways and mechanisms by which common disorders of obesity cause metabolic complications. Novel therapeutic approaches for patients with lipodystrophies also may have implications for treatment of the metabolic syndrome in patients with regional adiposity. This article reviews these recent advances in our knowledge of the clinical features, metabolic abnormalities, and pathogenetic or other bases of various types of lipodystrophies.

What is HIV-associated lipodystrophy? Defining fat distribution changes in HIV infection

PURPOSE OF REVIEW

The prevalence of lipodystrophy in HIV infection reported in the early literature has varied widely due in part to the different methods used in assessing and defining lipodystrophy in studies. There remains a lack of clarity regarding whether the peripheral lipoatrophy and central lipohypertrophy initially described in HIV infection are a result of separate mechanisms or a single mechanism. We review the current methods used to assess and define lipodystrophy in HIV infection; the prevalence and incidence of lipodystrophy reported in the recent HIV literature; and future directions in elucidating the morphologic changes associated with HIV infection.

RECENT FINDINGS

Different methods of assessing and defining lipodystrophy continue to lead to varying prevalence and incidence rates in recent large cross-sectional and prospective studies. Recent studies that include a predominantly HIV-uninfected comparison group and utilize bi-directional surveys to describe fat loss and fat gain in both peripheral and central body sites suggest that there is an HIV-associated lipoatrophy that affects both peripheral and central sites. In one study that used objective measures to quantify fat such as magnetic resonance imaging, HIV-associated subcutaneous lipoatrophy appeared to predominate when compared with a healthy control group.

SUMMARY

Peripheral and central lipoatrophy affecting subcutaneous fat is emerging as the dominant morphologic change associated with HIV infection when compared with those without known HIV infection. Studies of lipodystrophy in HIV infection should focus on lipoatrophy using direct measures of fat when possible.

Biological effects of short-term or prolonged administration of 9-[2-(phosphonomethoxy)propyl]adenine (tenofovir) to newborn and infant rhesus macaques

The reverse transcriptase inhibitor 9-[2-(phosphonomethoxy)propyl]adenine (PMPA; tenofovir) was previously found to offer strong prophylactic and therapeutic benefits in an infant macaque model of pediatric human immunodeficiency virus (HIV) infection. We now summarize the toxicity and safety of PMPA in these studies. When a range of PMPA doses (4 to 30 mg/kg of body weight administered subcutaneously once daily) was administered to 39 infant macaques for a short period of time (range, 1 day to 12 weeks), no adverse effects on their health or growth were observed; this included a subset of 12 animals which were monitored for more than 2 years. In contrast, daily administration of a high dose of PMPA (30 mg/kg subcutaneously) for prolonged periods of time (>8 to 21 months) to 13 animals resulted in a Fanconi-like syndrome (proximal renal tubular disorder) with glucosuria, aminoaciduria, hypophosphatemia, growth restriction, bone pathology (osteomalacia), and reduced clearance of PMPA. The adverse effects were reversible or were alleviated following either complete withdrawal of PMPA treatment or reduction of the daily regimen from 30 mg/kg to 2.5 to 10 mg/kg subcutaneously. Finally, to evaluate the safety of a prolonged low-dose treatment regimen, two newborn macaques were started on a 10-mg/kg/day subcutaneous regimen; these animals are healthy and have normal bone density and growth after 5 years of daily treatment. In conclusion, our findings suggest that chronic daily administration of a high dose of PMPA results in adverse effects on kidney and bone, while short-term administration of relatively high doses and prolonged low-dose administration are safe.

HIV-related lipodystrophy and related factors

As new therapies for HIV infection have been developed, some of the clinical focus related to AIDS and HIV infection has shifted from acute care, to more chronic issues. Some of these new clinical issues seem related to the HIV infection itself, while others seem to be side effects of therapeutic efforts. Metabolic abnormalities, such as dyslipidemia, insulin resistance, and lipodystrophy (LD) have been observed. The clinical importance of these is demonstrated by the increased prevalence of cardiovascular disease and diabetes in HIV infected persons. LD is a general term used to describe varying degrees of fat redistribution, including lipoatrophy and lipohypertrophy, in different body regions. Though LD was observed in persons with HIV infection before highly active treatment regimens were developed, the prevalence of LD has seemingly increased drastically with the widespread use of more active therapies. It has been postulated that protease inhibitors (PI), especially, are linked to the development of LD. This review will assess the epidemiologic information related to HIV-associated LD, and related metabolic syndromes. In addition, potential mechanisms accounting for these syndromes will be reviewed. In general, the available data do not define a single, definable etiology or mechanism explaining these clinical conditions, but suggest that these conditions are caused by a complex interaction potentially involving such things as the side effects of medications, alteration of immune function, and individual subject characteristics, such as body weight and baseline lipid level.

High Plasma Level of Interleukin-18 in HIV-Infected Subjects With Lipodystrophy

The level of interleukin-18 (IL-18) is elevated in patients with HIV infection as well as in people with insulin resistance (IR). As HIV-associated lipodystrophy (LD) shares metabolic characteristics with the metabolic syndrome, it was hypothesized that IL-18 would be elevated in patients with LD. Two groups of HIV-infected men with LD, one with fat accumulation (mixed group) (n = 12) and one without fat accumulation (lipoatrophic group) (n = 15) were included. Controls were HIV-positive men without LD (n = 15) and HIV-negative, age-matched men (n = 12). The levels of plasma IL-18 were elevated in all 3 HIV groups compared with HIV-negative controls (P <0.01). In the HIV groups the lipoatrophic group had the highest IL-18, followed by the mixed group and the HIV-positive controls. Only the differences between the lipoatrophic group and the HIV-positive controls were significant (P <0.01). Plasma IL-18 correlated with tumor necrosis factor-alpha (P <0.05), but not IL-6, adiponectin, or HOMA-IR (homeostasis model of insulin resistance). In contrast to the HIV-negative controls, IL-18 did not correlate with total or low-density cholesterol in either of the HIV groups. An inverse correlation was observed between IL-18 and limb fat (P <0.05). In conclusion, the level of IL-18 is elevated in patients with LD and closely linked to limb atrophy, whereas it is not associated with cholesterol or IR.