Emerging bone problems in patients infected with human immunodeficiency virus

Bone mineral density among virologically suppressed Asians older than 50 years old living with and without HIV: A cross-sectional study

There are limited data regarding bone health in older people living with HIV (PWH), especially those of Asian ethnicity. We aimed to determine whether BMD in well-suppressed HIV-infected men and women aged ≥ 50 years are different from HIV-uninfected controls. In a cross-sectional study, BMD by dual-energy X-ray absorptiometry and calciotropic hormones were measured. A total of 481 participants were consecutively enrolled (209 HIV+ men, 88 HIV- men, 126 HIV+ women and 58 HIV- women). PWH were on average 2.5 years younger [men: 55.0 vs. 57.5 yr; women: 54.0 vs. 58.0 yr] and had lower body mass index (BMI) [men: 23.2 vs. 25.1 kg/m2; women: 23.1 vs. 24.7 kg/m2] compared to the controls. The median duration since HIV diagnosis was 19 (IQR 15-21) years in men and 18 (IQR 15-21) years in women. Three-quarters of PWH had been treated with tenofovir disoproxil fumarate-containing antiretroviral therapy for a median time of 7.4 (IQR 4.5-8.9) years in men and 8.2 (IQR 6.1-10) years in women. In an unadjusted model, HIV+men had significantly lower BMD (g/cm2) at the total hip and femoral neck whereas there was a tend toward lower BMD in HIV+women. After adjusting for age, BMI, and other traditional osteoporotic risk factors, BMD of virologically suppressed older PWH did not differ from participants without HIV (P>0.1). PWH had lower serum 25(OH)D levels but this was not correlated with BMD. In conclusion, BMD in well-suppressed PWH is not different from non-HIV people, therefore, effective control of HIV infection and minimization of other traditional osteoporosis risk factors may help maintain good skeletal health and prevent premature bone loss in Asian PWH. Clinical trial registration: Clinicaltrials.gov # NCT00411983.

A tale of three pandemics: Shining a light on a hidden problem

An “epidemic” is an event in which a disease, infectious or non-infectious, is actively spreading within a population and designated area. The term “pandemic” is defined as “an epidemic occurring worldwide, or over a very wide area, crossing international boundaries and usually affecting a large number of people”.

The global response to the COVID-19 pandemic has not been seen since the outbreak of Human Immunodeficiency Virus in the early eighties. But there is another unseen pandemic running alongside the current COVID-19 pandemic, which affects a vast number of people, crossing international boundaries and occurring in every single country worldwide. The pandemic of traumatic injuries.

Traumatic injuries account for 11% of the current Global Burden of Disease, resulting in nearly 5 million deaths annually and is the third-leading cause of death worldwide. For every trauma-related death, it is estimated that up to 50 people sustain permanent or temporary disabilities. Furthermore, traumatic injuries occur at disproportionately higher rates in low- and middle-income countries, with approximately 90% of injuries and more than 90% of global deaths from injury occurring these countries.

Injuries are increasing worldwide, crossing international boundaries and affecting a large number of people, in the same manner Human Immunodeficiency Virus did in the 1980's and COVID-19 is today. The tremendous global effort to tackle the COVID-19 and Human Immunodeficiency Virus pandemics has occurred whilst ignoring the comparable pandemic of injury. Without change and future engagement with policy makers and international donors this disparity is likely to continue.

Impact of postpartum tenofovir-based antiretroviral therapy on bone mineral density in breastfeeding women with HIV enrolled in a randomized clinical trial

Objectives

We set out to evaluate the effect of postnatal exposure to tenofovir-containing antiretroviral therapy on bone mineral density among breastfeeding women living with HIV.

Design

IMPAACT P1084s is a sub-study of the PROMISE randomized trial conducted in four African countries (ClinicalTrials.gov number NCT01066858).

Methods

IMPAACT P1084s enrolled eligible mother-infant pairs previously randomised in the PROMISE trial at one week after delivery to receive either maternal antiretroviral therapy (Tenofovir disoproxil fumarate / Emtricitabine + Lopinavir/ritonavir–maternal TDF-ART) or administer infant nevirapine, with no maternal antiretroviral therapy, to prevent breastmilk HIV transmission. Maternal lumbar spine and hip bone mineral density were measured using dual-energy x-ray absorptiometry (DXA) at postpartum weeks 1 and 74. We studied the effect of the postpartum randomization on percent change in maternal bone mineral density in an intention-to-treat analysis with a t-test; mean and 95% confidence interval (95%CI) are presented.

Results

Among 398/400 women included in this analysis, baseline age, body-mass index, CD4 count, mean bone mineral density and alcohol use were comparable between study arms. On average, maternal lumbar spine bone mineral density declined significantly through week 74 in the maternal TDF-ART compared to the infant nevirapine arm; mean difference (95%CI) -2.86 (-4.03, -1.70) percentage points (p-value <0.001). Similarly, maternal hip bone mineral density declined significantly more through week 74 in the maternal TDF-ART compared to the infant nevirapine arm; mean difference -2.29% (-3.20, -1.39) (p-value <0.001). Adjusting for covariates did not change the treatment effect.

Conclusions

Bone mineral density decline through week 74 postpartum was greater among breastfeeding HIV-infected women randomized to receive maternal TDF-ART during breastfeeding compared to those mothers whose infants received nevirapine prophylaxis.

Antiretroviral-naïve HIV-infected patients had lower bone formation markers than HIV-uninfected adults

There are limited studies regarding bone health among people living with HIV (PLHIV) in Asia. We compared bone mineral density (BMD), serum 25-hydroxyvitamin D (25(OH)D) status and bone turnover markers (serum procollagen type1 N-terminal propeptide (P1NP), osteocalcin (OC) and C-terminal cross-linking telopeptide of type1 collagen) among 302 antiretroviral therapy (ART) naive PLHIV compared to 269 HIV-uninfected controls from Thailand. People aged ≥30 years, with and without HIV infection (free of diabetes, hypertension, and active opportunistic infection) were enrolled. BMD at the lumbar spine, total hip, and femoral neck were measured using Hologic DXA at baseline and at 5 years. We analyzed BMD, serum 25(OH)D levels, and bone turnover markers at the patients' baseline visit. PLHIV were 1.5 years younger and had lower BMI. PLHIV had higher mean serum 25(OH)D level and similar BMD to the controls. Interestingly, PLHIV had significantly lower bone formation (serum P1NP and OC), particularly those with low CD4 count. Only a few participants had low bone mass. ARV naïve middle-aged PLHIV did not have lower BMD or lower vitamin D levels compared to the controls. However, PLHIV had lower bone formation markers, particularly those with low CD4 count. This finding supports the benefit of early ART.

Osteonecrosis of the femoral head in people living with HIV: anatomopathological description and p24 antigen test

Objective

To examine the presence of HIV in bone tissue of people living with HIV (PLWHIV) with osteonecrosis of femoral head and describe clinical and anatomopathological findings.

Design

This is a case series which included 44 PLWHIV with osteonecrosis of femoral head who underwent total hip arthroplasty.

Methods

Clinical data were obtained through analysis of the patients’ medical records. Bone tissue obtained during total hip arthroplasty was retrieved and sent for conventional and immunohistochemical analysis. Monoclonal antibodies were used to mark the p24 (HIV), CD31 (vascular endothelial cells), CD68 (macrophages), and D₂40 (cells of the lymphatic endothelium) antigens.

Results

Dyslipidemia was found in 48% of the patients and lipodystrophy in 31%. Histological analysis showed similar characteristics for the entire sample. Degeneration of joint cartilage was visualized with the presence of fissures and fibrillations, as well as subchondral sclerosis and necrosis of the subchondral cancellous bone tissue. Lymphoplasmocytic inflammatory reaction was observed, with the presence of macrophages containing a foamy, vacuolated cytoplasm, as well as the presence of ceroid pigment and occasional granulation tissue. The reaction with the monoclonal anti-p24 antibody was negative in the samples from all 44 PLWHIV undergoing hip arthroplasty. Reactions with the anti-CD31 and anti-D₂40 antibodies were negative. Staining with CD68 antibody confirmed that the cells visualized with foamy, vacuolated cytoplasm were macrophages.

Conclusion

p24 HIV antigen was not detected in the bone tissue of PLWHIV and osteonecrosis. The most frequent anatomopathological findings were extensive necrosis of bone tissue, large vacuoles filled with fat cells, inflammatory lymphoplasmocytic reaction with macrophages containing vacuolated cytoplasm, and the presence of ceroid pigment.

Fracture management in HIV positive individuals: a systematic review

PURPOSE

Human immunodeficiency virus (HIV) infection could potentially play an important role in the management of fractures as they have been shown to affect fracture healing and the post-operative risk of implant sepsis.

METHODS

A systematic review of the relevant literature was performed on PubMed and Scopus databases. Twenty-six studies were identified, critiqued and analysed accordingly. No randomised controlled trials were identified.

RESULTS

HIV positivity was not shown to influence an individual's risk of early wound infection in operatively managed closed fractures. The rate of pin track infection in open injuries managed with external fixators was low. However, in open injuries managed with internal fixation, early wound infection rates were increased in the HIV-positive population compared to HIV-negative individuals. Regarding late implant infection, in closed fractures there appeared to be no increased risk of infection but there is limited evidence for open injuries. Additionally, further evidence is needed to establish if the rate of union in both open and closed fractures are influenced by HIV status.

CONCLUSION

Overall, no evidence was found to suggest that surgical management of fractures in the HIV population should be avoided, and fixation of closed fractures in the HIV population appeared to be safe. The effect of anti-retroviral therapy is unclear and this should be further researched. However, based on the limited evidence, caution should be taken in the management of open fractures due to the potentially increased infection risk. The impact of anti-retroviral therapy on the outcomes of surgery needs further evaluation.

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.

Bone health and HIV in resource-limited settings: a scoping review

PURPOSE OF REVIEW

Sub-Saharan Africa and other resource-limited settings (RLS) bear the greatest burden of the HIV epidemic globally. Advantageously, the expanding access to antiretroviral therapy (ART) has resulted in increased survival of HIV individuals in the last 2 decades. Data from resource rich settings provide evidence of increased risk of comorbid conditions such as osteoporosis and fragility fractures among HIV-infected populations. We provide the first review of published and presented data synthesizing the current state of knowledge on bone health and HIV in RLS.

RECENT FINDINGS

With few exceptions, we found a high prevalence of low bone mineral density (BMD) and hypovitaminosis D among HIV-infected populations in both RLS and resource rich settings. Although most recognized risk factors for bone loss are similar across settings, in certain RLS there is a high prevalence of both non-HIV-specific risk factors and HIV-specific risk factors, including advanced HIV disease and widespread use of ART, including tenofovir disoproxil fumarate, a non-BMD sparing ART. Of great concern, we neither found published data on the effect of tenofovir disoproxil fumarate initiation on BMD, nor any data on incidence and prevalence of fractures among HIV-infected populations in RLS.

SUMMARY

To date, the prevalence and squeal of metabolic bone diseases in RLS are poorly described. This review highlights important gaps in our knowledge about HIV-associated bone health comorbidities in RLS. This creates an urgent need for targeted research that can inform HIV care and management guidelines in RLS.

Changing Trends in Complications and Mortality Rates Among US Youth and Young Adults With HIV Infection in the Era of Combination Antiretroviral Therapy

BACKGROUND

Combination antiretroviral therapy (cART) has resulted in a dramatic decrease in human immunodeficiency virus (HIV)-related opportunistic infections and deaths in US youth, but both continue to occur.

METHODS

We estimated the incidence of complications and deaths in IMPAACT P1074, a long-term US-based prospective multicenter cohort study conducted from April 2008 to June 2014. Incidence rates of selected diagnoses and trends over time were compared with those from a previous observational cohort study, P219C (2004-2007). Causes of death and relevant demographic and clinical features were reviewed.

RESULTS

Among 1201 HIV-infected youth in P1074 (87% perinatally infected; mean [standard deviation] age at last chart review, 20.9 [5.4] years), psychiatric and neurodevelopmental disorders, asthma, pneumonia, and genital tract infections were among the most common comorbid conditions. Compared with findings in P219C, conditions with significantly increased incidence included substance or alcohol abuse, latent tuberculosis, diabetes mellitus, atypical mycobacterial infections, vitamin D deficiency or metabolic bone disorders, anxiety disorders, and fractures; the incidence of pneumonia decreased significantly. Twenty-eight deaths occurred, yielding a standardized mortality rate 31.5 times that of the US population. Those who died were older, less likely to be receiving cART, and had lower CD4 cell counts and higher viral loads. Most deaths (86%) were due to HIV-related medical conditions.

CONCLUSIONS

Opportunistic infections and deaths are less common among HIV-infected youth in the US in the cART era, but the mortality rate remains elevated. Deaths were associated with poor HIV control and older age. Emerging complications, such as psychiatric, inflammatory, metabolic, and genital tract diseases, need to be addressed.

Treatment of severe non-infectious uveitis in high-risk conditions (Part 2): systemic infections; management and safety issues

INTRODUCTION

Management of patients with severe immune-mediated uveitis requires the use of immunosuppressive (IS) drugs in selected cases. This may be particularly challenging in certain patients with associated conditions, which may increase the risk of side effects or modify guidelines for the use of such drugs. Chronic viral and mycobacterial infections in the setting of non-infectious uveitis create a number of diagnostic but also therapeutic dilemmas to clinicians because they can be exacerbated by IS therapies with detrimental effects.

AREAS COVERED

In this review, we will focus on very specific chronic infections that can be affected by IS therapies: human immunodeficiency virus infection, chronic hepatitis virus infection and tuberculosis. The main aim of this review is to provide an updated and comprehensive practical guide for practitioners regarding the therapeutic decision-making and management of patients with non-infectious uveitis affected by the aforementioned infectious conditions.

EXPERT OPINION

Clinicians should be aware of the risk of viral and mycobacterial reactivation of an underlying infection during IS therapy. However, most of these conditions do not represent an absolute contraindication if one were able to apply an appropriate prior screening and close monitoring of such therapy.

Prevalence and predictors of low bone mineral density and fragility fractures among HIV-infected patients at one Italian center after universal DXA screening: sensitivity and specificity of current guidelines on bone mineral density management

Low bone mineral density (BMD) is frequent in HIV infection regardless of the use of antiretroviral therapy (ART). Uncertainties remain, however, as to when in HIV infection BMD screening should be performed. We designed a prospective study to estimate the efficacy of universal BMD screening by dual-energy X-ray absorptiometry (DXA). Since April 2009 through March 2011, HIV patients attending our Center were offered femoral/lumbar DXA to screen BMD. Low BMD for chronological age, that is significant osteopenia, was defined as a Z-score ≤ -2.0 at femur and lumbar spine. Nontraumatic bone fractures (NTBFs) were evaluated. The final sample included 163 patients. A Z-score ≤ -2.0 at any site was observed in 19.6% of cases: among these, 18.8% had no indication to DXA using current Italian HIV guidelines for BMD screening. A lower femoral Z-score was independently associated with lower BMI, AIDS diagnosis, HCV co-infection, antiretroviral treatment, and NTBFs; a lower lumbar Z-score with age, BMI, Nadir CD4 T-cell counts, and NTBFs. Prevalence of NTBFs was 27.0%, predictors being male gender, HCV co-infection, and lower femoral Z-scores. Our results suggest that measuring BMD by DXA in all HIV patients regardless of any further specification may help retrieving one-fifth of patients with early BMD disorders not identified using current criteria for selective screening of BMD.

Neutropenia during HIV infection: adverse consequences and remedies

Neutropenia frequently occurs in patients with Human immunodeficiency virus (HIV) infection. Causes for neutropenia during HIV infection are multifactoral, including the viral toxicity to hematopoietic tissue, the use of myelotoxic agents for treatment, complication with secondary infections and malignancies, as well as the patient's association with confounding factors which impair myelopoiesis. An increased prevalence and severity of neutropenia is commonly seen in advanced stages of HIV disease. Decline of neutrophil phagocytic defense in combination with the failure of adaptive immunity renders the host highly susceptible to developing fatal secondary infections. Neutropenia and myelosuppression also restrict the use of many antimicrobial agents for treatment of infections caused by HIV and opportunistic pathogens. In recent years, HIV infection has increasingly become a chronic disease because of progress in antiretroviral therapy (ART). Prevention and treatment of severe neutropenia becomes critical for improving the survival of HIV-infected patients.

Chronic viral hepatitis is associated with low bone mineral density in HIV-infected patients, ANRS CO 3 Aquitaine Cohort

BACKGROUND

High prevalence rates of low bone mineral density (BMD) have been reported in people living with HIV infection. We aimed to investigate the association of chronic viral hepatitis with low BMD in HIV-infected patients.

METHODS

A hospital-based cohort of HIV-infected patients was screened for hepatitis B and C coinfection. BMD was measured by dual energy x-ray absorptiometry. T-score was used to define bone status according to the World Health Organization's classification; moreover, each observed BMD value was compared with reference to an average person of the same age and gender as a Z-score <-2.0 allow the diagnosis of patients having less bone mass and/or losing bone material more rapidly than expected. A polytomial logistic regression was performed by gender to investigate the association between chronic viral hepatitis and low BMD (osteopenia and osteoporosis) in HIV-infected patients.

RESULTS

A total of 626 patients (166 females of whom 52 postmenopausal) were recruited: 357 HIV monoinfected, and 269 HIV-coinfected with chronic viral hepatitis, among whom 61 with a diagnosis of cirrhosis. Osteopenia was present in 320 patients (51.1%) and osteoporosis in 187 (29.9%). After adjustment, osteoporosis was associated with older age and low body mass index in both genders. The association between chronic viral hepatitis B or C and osteoporosis was found in women only (odds ratio: 19.0; P value: 0.047).

CONCLUSIONS

We found a high prevalence of low BMD overall, but chronic viral hepatitis was independently associated with osteoporosis only in female participants. Our data confirm the need of BMD evaluations for patients living with HIV.

The Role of Inflammatory Cytokines, the RANKL/OPG Axis, and the Immunoskeletal Interface in Physiological Bone Turnover and Osteoporosis

Although it has long been recognized that inflammation, a consequence of immune-driven processes, significantly impacts bone turnover, the degree of centralization of skeletal and immune functions has begun to be dissected only recently. It is now recognized that formation of osteoclasts, the bone resorbing cells of the body, is centered on the key osteoclastogenic cytokine, receptor activator of NF- κ B ligand (RANKL). Although numerous inflammatory cytokines are now recognized to promote osteoclast formation and skeletal degradation, with just a few exceptions, RANKL is now considered to be the final downstream effector cytokine that drives osteoclastogenesis and regulates osteoclastic bone resorption. The biological activity of RANKL is moderated by its physiological decoy receptor, osteoprotegerin (OPG). New discoveries concerning the sources and regulation of RANKL and OPG in physiological bone turnover as well as under pathological (osteoporotic) conditions continue to be made, opening a window to the complex regulatory processes that control skeletal integrity and the depth of integration of the skeleton within the immune response. This paper will examine the interconnection between bone turnover and the immune system and the implications thereof for physiological and pathological bone turnover.

Impact of age on markers of HIV-1 disease

Aging is a complicated process characterized by a progressive loss of homeostasis, which results in an increased vulnerability to multiple diseases. HIV-1-infected patients demonstrate a premature aging phenotype and develop certain age-related diseases earlier in their lifespan than what is seen in the general population. Age-related comorbidities may include the development of bone disease, metabolic disorders, neurologic impairment and immunosenescence. Age also appears to have an effect on traditional markers of HIV-1 disease progression, including CD4+ T-cell count and viral load. These effects are not only a consequence of HIV-1 infection, but in many cases, are also linked to antiretroviral therapy. This review summarizes the complex interplay between HIV-1 infection and aging, and the impact that aging has on markers of HIV-1 disease.

Vitamin D deficiency and its association with low bone mineral density, HIV-related factors, hospitalization, and death in a predominantly black HIV-infected cohort

BACKGROUND

Low bone mineral density (BMD) is common among patients infected with human immunodeficiency virus (HIV) and present in higher rates in black subjects. This study assessed vitamin D levels in HIV cases versus noninfected matched controls to determine if deficiency was associated with BMD and HIV clinical outcomes.

METHODS

In total, 271 military beneficiaries with HIV underwent dual energy x-ray absorptiometry (DEXA) screening in 2001-2. Serum 25OH-vitamin D levels were determined using stored serum from the time of DEXA and 6-18 months prior. Two non-HIV-infected controls for each active duty case (n = 205) were matched on age, sex, race, zip code, and season using the Department of Defense Serum Repository (DoDSR). Vitamin D levels <20 ng/mL were considered deficient. HIV-related factors and clinical outcomes were assessed using data collected in the DoD HIV Natural History study.

RESULTS

In total, 165 of 205 (80.5%) active duty HIV cases had 2 matched controls available. HIV cases had greater odds of for vitamin D deficiency (VDD) compared with controls (demographics adjusted paired data odds ratio [OR], 1.46, 95% confidence interval [CI], .87-2.45), but this was not statistically significant. Blacks were disproportionately deficient (P <.001) but not relative to HIV status or BMD. Low BMD was associated with typical risk factors (low body mass index and exercise levels, alcohol use); given limited available data the relationship between tenofovir exposure and VDD or low BMD could not be determined. Analysis of HIV-specific factors and outcomes such as exposure to antiretrovirals, HIV progression, hospitalizations, and death revealed no significant associations with vitamin D levels.

CONCLUSIONS

VDD was highly prevalent in black HIV- infected persons but did not explain the observed racial disparity in BMD. Vitamin D deficiency was not more common among HIV- infected persons, nor did it seem associated with HIV- related factors/clinical outcomes.

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.

The Relationship Between HIV Infection and Cardiovascular Disease

Over 30 million people are currently living with human immunodeficiency virus (HIV) infection, and over 2 million new infections occur per year. HIV has been found to directly affect vascular biology resulting in an increased risk of cardiovascular disease compared to uninfected persons. Although HIV infection can now be treated effectively with combination antiretroviral medications, significant toxicities such as hyperlipidemia, diabetes, and excess cardiovascular co-morbidity; as well as the potential for significant drug-drug interactions between HIV and cardiovascular medications, present new challenges for the management of persons infected with HIV. We first review basic principles of HIV pathogenesis and treatment and then discuss relevant clinical management strategies that will be useful for cardiologists who might be involved in the care of HIV infected patients.

Osteonecrosis in human immunodeficiency virus (HIV)-infected patients: a multicentric case-control study

Osteonecrosis (ON) is a rare disabling complication occurring in patients with human immunodeficiency virus (HIV) infection at a higher frequency than in the general population despite effective combination antiretroviral therapy being made available, as recently documented by several retrospective studies. We designed a multicentric case-control study among HIV-infected patients cared for at institutions in the Italian CISAI group (Italian Study Group for Adverse Events in HIV Infection) to search for additional predictors of ON in this special population. All centers which observed at least one case of ON were requested to report data for central re-evaluation. Parallel HIV-positive, ON-free controls were randomly selected and matched with confirmed cases of ON for sex, age and CD4 T-cell counts at the time of HIV diagnosis. Fifteen cases and controls were included in the final sample. Univariate statistical analyses revealed a significant association between ON and exposure to steroids (P = 0.001), exposure to one or more drugs in addition to HAART (Highly Active Anti-Retroviral Therapy) (P = 0.03), high titers of total serum IgE (P = 0.02), loss of working ability (P = 0.03), triglycerides levels over 200 mg/dL before antiretrovirals (P = 0.03) and cholesterol levels over 200 mg/dL before and after antiretrovirals (P = 0.03 and 0.05, respectively). High serum IgE levels and loss of working ability in advance of ON appeared for the first time as possible predictors of ON in HIV patients, while long-term exposure to steroids, combined hyperlipemia and chronic treatment with other drugs in addition to antiretrovirals were confirmed. Predicting and preventing ON in the individual HIV-infected patient is therefore a clinically challenging opportunity.

Prevalence of Lipodystrophy and Dyslipidemia among Patients with HIV Infection on Generic ART in Rural South India

As antiretroviral therapy (ART) becomes more available to the HIV-infected population, it is important to determine the prevalence of its long-term complications. In this cross-sectional study, 145 HIV-positive patients on ART, 146 HIV-positive patients not on ART, and 72 HIV-negative individuals visiting the Namakkal District Head Quarters Hospital, Tamil Nadu, India, were recruited from February 2007 to April 2009. Among the patients on ART, the prevalence of lipodystrophy was 60.7%; 22.7% with lipohypertrophy, 51.1% with lipoatrophy, and 22.7% with mixed pattern. The proportion of patients with dyslipidemia was significantly higher in the treatment group when compared to ART-naive and HIV-negative controls ( P = .00). Total duration of ART was significantly associated with lipodystrophy ( P = .04) and dyslipidemia ( P = .01). Also, by logistic regression, abnormal metabolic levels were a risk factor in lipodystrophy ( P = .02). This study highlights the need for development of inexpensive and accessible treatments for the reduction of lipodystrophy.

Position of the American Dietetic Association: Nutrition Intervention and Human Immunodeficiency Virus Infection

It is the position of the American Dietetic Association that efforts to optimize nutritional status through individualized medical nutrition therapy, assurance of food and nutrition security, and nutrition education are essential to the total system of health care available to people with human immunodeficiency virus (HIV) infection throughout the continuum of care. Broad-based efforts to improve health care access and treatment have stabilized HIV prevalence levels in many parts of the world and led to longer survival for people living with HIV infection. Confounding clinical and social issues, such as medication interactions, comorbidities, wasting, lipodystrophy, food insecurity, aging, and other related conditions further complicate disease management. With greater understanding of the mechanisms of HIV disease and its impact on body function, development of new treatments, and wider ranges of populations affected, the management of chronic HIV infection continues to become more complex and demanding. Achievement of food and nutrition security and management of nutrition-related complications of HIV infection remain significant challenges for clients with HIV infection and health care professionals. Registered dietitians and dietetic technicians, registered, should integrate their efforts into the overall health care strategies to optimize their clinical and social influence for people living with HIV infection.

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.

Hormonal contraception and HIV-positive women: metabolic concerns and management strategies

As HIV-positive women live longer lives, and as testing for HIV becomes more routine, clinicians can expect to see more HIV-positive women in their practices. The need to be aware of management issues particular to this population becomes increasingly important. Metabolic dysregulation is a common, long-term complication associated with HIV and is one of the most difficult to manage. Hormonal contraception also is associated with metabolic dysregulation. As more HIV-positive women choose long-term, reversible contraception, the potential for concomitant and additive side effects, and the need for careful, proactive management strategies to avoid these complications, will become more important. This article reviews research detailing the metabolic dysfunction associated with hormonal contraception and with HIV-seropositivity. It highlights reasons for concern regarding the potential, although as yet theoretical, increased risk for metabolic dysfunction when hormonal contraception is used in the presence of HIV. Suggestions for management strategies for women living with HIV who choose to use hormonal contraception are presented. These strategies should be viewed as suggestions for management until substantitive research becomes available.

HIV-1 triggers apoptosis in primary osteoblasts and HOBIT cells through TNFalpha activation

Several HIV-1 infected patients show bone loss and osteopenia/osteoporosis during the course of disease. The mechanisms underlying this degenerative process are largely unsettled and it has not been determined yet whether bone dysfunction is linked to HIV-1-mediated direct and/or indirect effects on osteoblasts/osteoclasts cross-talk regulation. This study investigated the effects of HIV-1(IIIb) and HIV-1(ADA) strains on osteoblasts using the osteoblast-derived cell line (HOBIT) and primary human osteoblasts as cellular models. The challenge of these cell cultures by both HIV-1 strains triggered a significant apoptosis activation unrelated to viral infection, since proviral HIV-1 DNA and supernatant HIV-1 RNA were not detected by real time PCR or b-DNA assays respectively. Under the experimental conditions, even heat-inactivated HIV-1 or cross-linked recombinant gp120 treatment of HOBIT and osteoblasts induced programmed cell death, suggesting that apoptosis is regulated by the interaction between HIV-1 gp120 and cell membrane. The analysis of cell culture supernatants showed a significant up-regulation of TNFalpha, a pleiotropic protein considered an apoptosis inducer in the osteoblast model. In fact, pretreatment of HOBIT and osteoblast cell cultures with anti-TNFalpha polyclonal antibody tackled effectively HIV-1 related induction of cell apoptosis. As a whole, these results indicate that HIV-1 may impair bone mass structure homeostasis by TNFalpha regulated osteoblast apoptosis.

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.

[Bone mineral loss in patients with human immunodeficiency virus infection]

Life expectancy and quality of life among patients infected with human immunodeficiency virus (HIV) has dramatically improved with the advent of highly active antiretroviral therapy. Nonetheless, with the transformation of HIV infection into a chronic disease, a series of long-term consequences have been observed, among them osteoporosis. The prevalence of this condition is increasing among individuals with HIV infection. Although an epidemic of fragility fractures has not been described in these patients, an increase in the incidence of such fractures is anticipated as the HIV population ages, and this will undoubtedly have an impact on their quality of life. The numerous factors that favor the development of osteoporosis in these patients are related to the infection, itself, and the treatment received.

Risks of immunosuppressive therapies including biologic agents in patients with rheumatic diseases and co-existing chronic viral infections

PURPOSE OF REVIEW

A number of chronic viral infections could be reactivated by immunosuppressive agents used in rheumatic diseases. In this review, we will focus on the complex effect of immunosuppressive agents, including biologic agents, on the natural course of chronic viral infections as well as an approach to the prevention and management of therapy-induced viral reactivation.

RECENT FINDINGS

Chronic viral infections that are affected by immunosuppression in the setting of an underlying rheumatic disease include those due to hepatitis B virus, hepatitis C virus, or human immunodeficiency virus, and latent infections from Epstein-Barr virus, JC virus, or varicella zoster virus. The most recent data of the effects of immunosuppressive agents are reviewed, with special emphasis on the effects of biologic therapies (anti-tumor necrosis factor, anti-B cell), on these viral agents.

SUMMARY

Clinicians should be aware of the risk for viral reactivation of an underlying chronic viral infection during immunosuppressive therapy. Despite the existence of such risk, the presence of chronic viral infection is not a contraindication to immunosuppressive therapy, given that appropriate pretherapy screening and close monitoring is applied.

Reduced bone mineral density in HIV-infected patients: prevalence and associated factors

BACKGROUND

There is a high prevalence of bone demineralization among HIV-infected patients but mechanisms of alteration of bone turnover are still unclear and it is thought to be multifactorial.

METHODS

A cross-sectional survey of 492 HIV-infected patients within the Aquitaine cohort estimated the prevalence of osteoporosis/osteopenia and investigated associated factors. Bone mineral density of total body, lumbar spine and femoral neck was measured by dual-energy X-ray absorptiometry. Multivariable analyses of the association with HIV disease status, treatment and anthropometric parameters were stratified according to gender.

RESULTS

Median age was 43 years (interquartile range, 38-50); 73% were male; 19.7% patients had reached AIDS, 93.1% were treated with HAART; and 28.5% had lipodystrophy. Based on World Health Organization criteria, osteopenia was diagnosed in 54.6% of men [95% confidence interval (CI), 49.4-59.7) and 51.1% of women (95% CI, 42.6-59.6) and osteoporosis in 33.7% of men (95% CI, 28.8-38.6) and 8.3% of women (95% CI, 3.6-13.9). Using a polytomous logistic regression, older age, homosexual transmission group, low body mass index and low HIV plasma viral load were associated with the diagnosis of bone abnormalities in men, whereas older age and low CD4 lymphocyte count nadir were independently associated with osteoporosis/osteopenia in women. The use of HAART was not related to osteoporosis after adjustment (P = 0.58).

CONCLUSIONS

This cohort-based survey showed a high prevalence of osteopenia and osteoporosis of multifactorial origin. Mechanisms and consequences of these bone disorders need to be investigated.

Induction of cardiovascular pathology in a novel model of low-grade chronic inflammation

OBJECTIVE

Epidemiological and clinical evidence indicate that inflammatory processes play a pivotal role in a number of conditions associated with aging, including osteoporosis and cardiovascular diseases. The purpose of this study was to evaluate cardiovascular pathology and select inflammatory mediators of interest in a model of low-grade inflammation-induced osteopenia.

METHODS

Slow-release pellets were subcutaneously implanted in male rats to deliver 0, 3.3, or 33.3 microg of lipopolysaccharide (LPS)/day for 90 days. Tail blood was collected at 1, 2, and 3 months for differential white cell counts, and at the end of the study, hearts were harvested for histological and immunohistochemical evaluation.

RESULTS

The low-grade inflammatory response was characterized by elevated peripheral blood neutrophils and monocytes. Histological examination of heart cross sections revealed increased fibrous tissue, infiltration of lymphocytes, accumulation of mast cells, and roughened intimal borders within the arteries and arterioles, consistent with vascular disease. Inflammatory mediators (cyclooxygenase-2, tumor necrosis factor-alpha, and interleukin-1 beta) were up-regulated, and increased expression of platelet endothelial cell adhesion molecule-1 and receptor activator for NF-kappaB ligand was localized to the microvasculature endothelium.

CONCLUSIONS

These findings suggest that inflammation induced by chronic exposure to LPS produces cardiovascular pathology in the smaller intramural arteries and arterioles and support the utility of this model for further mechanistic and therapeutic studies focused on the role of chronic inflammation in cardiovascular disease.

Osteoporosis and multiple fractures in an antiretroviral-naive, HIV-positive child

As a result of the increased incidence of osteopenia and osteoporosis in HIV-infected patients, numerous publications have suggested that there may be a link between bone metabolism alterations and HIV infection. The early bone loss seen in these patients was initially attributed to the use of highly active antiretroviral treatment (HAART) that included protease inhibitors. Recent studies, however, have suggested that it may be a direct consequence of the viral infection on bone metabolism, persistent activation of pro-inflammatory cytokines (TNFa), or altered vitamin D metabolism secondary to the virus, combined with subsequent factors (e.g., antiretroviral treatment) that aggravate the bone demineralization. We present an antiretroviral-naive 6-year-old girl with vertically transmitted HIV infection who presented with severe osteoporosis and multiple pathological fractures of the vertebrae, ribs, and upper and lower limbs. The child was treated with HAART, appropriate nutritional support for her age, physiotherapy and rehabilitation, calcium and vitamin D supplements, and alendronate therapy. After 6 weeks of treatment, the intense pain and muscle atrophy had disappeared and she was able to walk unassisted. At 6 months, bone mass had increased by 72%. The interest of this case lies in the presence of severe osteoporosis and multiple pathological fractures in an HIVinfected naive child. To date, this condition has only been described in patients treated with antiretrovirals. Moreover, this is the first reported HIV-positive pediatric patient treated with bisphosphonates, which proved to be highly successful.

HIV protease inhibitors selectively induce gene expression alterations associated with reduced calcium deposition in primary human osteoblasts

HIV-infected patients are at increased risk of decreased bone mineral density. Some studies have implicated antiretroviral therapy as a contributor to the decreased bone mineral density seen in treated HIV-1 patients. In this study we explore the interactions between protease inhibitors (PI) and primary human osteoblast gene expression, highlighting a group of dysregulated genes that potentially are key factors in reducing bone formation. Runx-2 mRNA expression, calcium deposition, and alkaline phosphatase (ALP) activity decreased significantly in human osteoblast cultures after exposure to the PIs nelfinavir (NFV) and indinavir (IDV). Saquinavir (SQV), ritonavir (RTV), indinavir (IDV), or nelfinavir (NFV) exposure induced significant changes in genotypic expression as assessed by gene-chip microarray analysis. The altered genes from each group were compared to each other and a list of 8 upregulated and 13 downregulated genes only after NFV and IDV exposure was identified. This set includes TIMP-3, which has previously been demonstrated to be involved in osteoblast differentiation and extracellular matrix development processes. Silencing TIMP-3 mRNA expression using siRNA duplexes enhanced calcium deposition and ALP activity significantly, even after exposure to NFV and IDV. Our data suggest a link between reduced osteoblastic phenotype and a group of 21 altered genes following NFV and IDV treatment, and also suggest TIMP-3 may be involved in the PI-induced inhibition of osteoblast function.

RANKL/OPG/TRAIL plasma levels and bone mass loss evaluation in antiretroviral naive HIV-1-positive men

Osteopenia and osteoporosis are common in HIV-1-infected individuals and represent a challenge in clinical and therapeutic management. This report investigated osteopenia/osteoporosis in a group of 31 antiretroviral naive HIV-1-positive men and the role of specific molecules belonging to TNF and the TNF-receptor family in HIV-1-related bone mass loss. Osteoprotegerin (OPG), the receptor activator of NF-kappab-ligand (RANKL), and the TNF-related apoptosis-inducing ligand (TRAIL) were significantly increased in the plasma of antiretroviral naive HIV-1-positive patients compared to a control group of healthy blood donors. In addition, TRAIL and RANKL plasma concentrations were positively correlated to HIV-1-RNA viral load. Measurement of bone mineral density in 20 out of 31 HIV-1-positive subjects disclosed osteopenia/osteoporosis in 40% of these patients. The antiretroviral naive HIV-1-positive subjects with low bone mineral density had a decreased plasma OPG/RANKL ratio and a plasma RANKL concentration >500 pg/ml. Together, these data indicate that plasma concentrations of specific factors involved in bone homeostasis were increased during HIV-1 infection and that RANKL and OPG/RANKL ratio deregulation may be involved in osteopenia/osteoporosis occurring in antiretroviral naive HIV-1 individuals.

Dehydroepiandrosterone (DHEA) effects on HIV replication and host immunity: a randomized placebo-controlled study

Prior studies have indicated that dehydroepiandrosterone (DHEA) may have immunomodulatory properties as well as positive effects on mood, quality of life, and body composition. Preliminary data suggest that DHEA inhibits expression of human immunodeficiency virus 1 (HIV) in latently infected cells; thus, it might be a potential adjunct to currently available antiretroviral therapy. The objective was to determine DHEA's impact on latent HIV infection, persistent viral replication, immunity, and nonimmune aspects of health restoration. A randomized, double-blind, placebo-controlled 24-week outpatient intervention included 40 subjects with suppressed HIV viremia on a stable antiretroviral regimen. Participants were randomized with equal probability to receive either DHEA or placebo for 12 weeks, followed by open-label DHEA for an additional 12 weeks. Intensive virologic monitoring included plasma viral load assays (lower limits of detection 50 copies/ml and 2.5 copies/ml) and quantitative cultures of replication-competent virus reservoirs in blood cells. A full battery of immunologic measurements was performed. Measurements of hormones, body weight, and body composition were obtained. Quality of life was assessed using validated questionnaires. DHEA was bioavailable as ascertained by increased levels of DHEA, DHEA(S), and androstenedione in recipients' plasma compared to the control group. The titers of infectious HIV culturable from blood trended upward in the DHEA arm although there was no significant change in plasma HIV RNA level. No significant immune effects were observed with DHEA. There appeared to be no benefit with regard to lean muscle mass or bone density in the DHEA recipients. DHEA treatment had a positive impact on overall quality of life. DHEA supplementation in fully suppressed HIV patients was associated with an improvement in quality of life but appeared to have no beneficial antiviral, immunomodulatory, hormonal, or body composition effects, suggesting that it not be routinely used as an adjunctive therapy in this population.

A role for IRF3-dependent RXRalpha repression in hepatotoxicity associated with viral infections

Viral infections and antiviral responses have been linked to several metabolic diseases, including Reye's syndrome, which is aspirin-induced hepatotoxicity in the context of a viral infection. We identify an interferon regulatory factor 3 (IRF3)-dependent but type I interferon-independent pathway that strongly inhibits the expression of retinoid X receptor alpha (RXRalpha) and suppresses the induction of its downstream target genes, including those involved in hepatic detoxification. Activation of IRF3 by viral infection in vivo greatly enhances bile acid- and aspirin-induced hepatotoxicity. Our results provide a critical link between the innate immune response and host metabolism, identifying IRF3-mediated down-regulation of RXRalpha as a molecular mechanism for pathogen-associated metabolic diseases.

Modulation of osteoclastogenesis induced by nucleoside reverse transcriptase inhibitors

Osteopenia is a common and debilitating side-effect of HAART, yet little is known concerning the effects of HAART on bone metabolism. We reported previously that zidovudine (AZT) stimulates osteoclastogenesis in vitro and causes osteopenia in mice. Here, we confirmed that the AZT-induced osteoclastogenesis is dependent on RANKL in that osteoclastogenesis is blocked by osteoprotegestin. Alendronate, which is used for the treatment of osteopenia and osteoporosis, failed to inhibit AZT-induced osteoclastogenesis in vitro. Osteoclastogenesis in vitro was not affected by tumor necrosis factor-alpha. Two other NRTI drugs, ddl and 3TC, also induced osteoclastogenesis in vitro and induced osteopenia in mice. The osteopenia was associated with an elevation of parameters of osteoclasts, but not with osteoblasts. Combinations of the NRTIs did not result in additive or synergistic effects in vitro or in vivo. Finally, AZT induced osteoclastogenesis of human osteoclast precursors in a RANKL-dependent manner. This in vitro osteoclastogenesis assay using human peripheral blood mononuclear cells could be useful in evaluating bone turnover and the risk of developing osteopenia in AIDS patients on HAART.

Potential predictive factors of osteoporosis in HIV-positive subjects

Recent reports showed a high frequency of osteopenia/osteoporosis in HIV-infected subjects. Mechanism on the basis of this alteration is still unclear, as the direct effect of virus or of antiretroviral drugs. One hundred sixty-one consecutive HIV-infected outpatients aged 30-50 years, both naive and HAART-treated for >1 year, were included. An interview questionnaire was performed to establish prior pathological, toxic, epidemiological histories, medications intake, physical activity and eating habits. Blood and urinary tests were checked to exclude concomitant diseases, as were markers of bone metabolism and vitamin D3-metabolites. Each subject underwent to a lumbar spine and left hipbone mineral density by DEXA, using WHO criteria for diagnosis of osteopenia/osteoporosis. Radiologist was unaware if the subject was receiving HAART or not. For groups' homogeneity Chi-square, Fisher's exact and Student's t tests were used. Logistic regression analysis was used to find predictors of osteopenia/osteoporosis and linear regression model to find differences in bone mass density. The demographic characteristics of the 48 naive subjects and the 113 on HAART were comparable. Eighty subjects (49.7%) showed osteopenia/osteoporosis: 22 (45.8%) naive and 58 (51.3%) on HAART (P = 0.46). Independent predictors of osteopenia/osteoporosis were female gender (OR: 3.02, 95% CI: 1.26-7.25, P = 0.01 vs. male), older age (OR: 1.10, 95% CI: 1.01-1.20, P = 0.03, for each additional year), low body mass index (OR: 0.78, 95% CI: 0.68-0.91, P = 0.001 for each additional unit) and higher HIV-RNA levels at DEXA (OR: 1.97, 95% CI: 1.16-3.34, P = 0.01 for each additional Log(10)), whereas the use of HAART (OR: 2.61, 95% CI: 0.66-10.27, P = 0.17 vs. naive) and the alterations of markers of bone metabolism were not significantly related to osteopenia/osteoporosis. Similar findings were obtained using linear regression model analysis. HIV-infected subjects have a high frequency of osteopenia/osteoporosis. Traditional risk factors are predictive of osteopenia/osteoporosis also in HIV-subjects; the association with higher HIV-RNA levels can suggest a direct role of HIV itself in the occurrence of bone disease.

Pathogenesis of osteopenia/osteoporosis induced by highly active anti-retroviral therapy for AIDS

The advent of highly active anti-retroviral therapy (HAART) has dramatically decreased the rate of AIDS-related mortality and significantly extended the life span of patients with AIDS. A variety of metabolic side effects are associated with these therapies, one of which is metabolic bone disease. A higher prevalence of osteopenia and osteoporosis in HIV-infected patients receiving anti-retroviral therapy than in patients not on therapy has now been reported in several studies. Several factors have been demonstrated to influence HIV-associated decreases in bone mineral density (BMD), including administration of nucleoside reverse transcriptase inhibitors (NRTIs). In this article, discussion will focus on the molecular pathogenesis and treatment of HAART-associated osteopenia and osteoporosis.

Rheumatic complications of human immunodeficiency virus infection in the era of highly active antiretroviral therapy: emergence of a new syndrome of immune reconstitution and changing patterns of disease

OBJECTIVE

To describe the impact of the introduction of highly active antiretroviral therapy (HAART) on the nature and frequency of rheumatic complications in human immunodeficiency virus (HIV)-infected patients.

METHODS

Case report and systematic review of a newly described syndrome of rheumatic immune reconstitution syndrome and prospective longitudinal cohort study analyzing the frequency and nature of rheumatic complications in the setting of HIV infection from 1989 through 2000.

RESULTS

A newly described syndrome of either the de novo appearance or the exacerbation of clinically occult autoimmunity following immune reconstitution from HAART is described. Including the present case report, 32 cases have been individually described with sarcoidosis and autoimmune thyroid disease being most common with arthritis and various forms of connective tissue disease making up the rest. The mean onset to their appearance following HAART was nearly 9 months and most resolved with little or no therapy. In addition, a longitudinal analysis of 395 HIV-infected patients from 1989 to 2000 designed to detect the appearance of rheumatic complications has revealed a dramatic decline in certain problems such as reactive arthritis, psoriatic arthritis, and various forms of connective tissue disease. New rheumatic complications possibly due to the effects of longer survival and metabolic derangements associated with this form of therapy are now being described and may become more formidable problems in this population in the future.

CONCLUSIONS

HAART has had a profound beneficial effect on survival in HIV-infected patients but has also contributed to both an altered frequency and a different nature of rheumatic complications now being observed in this population. Rheumatologists need to be aware of these changes to provide optimal diagnosis and treatment for this group.

Systemic bone loss and induction of coronary vessel disease in a rat model of chronic inflammation

Clinically, osteopenia or low bone mass has been observed in a variety of chronic inflammatory diseases, and elevated proinflammatory mediators have implicated this process. The purpose of this study was to develop an in vivo model of bone loss induced by chronic systemic inflammation. Time-release pellets designed to deliver one of three doses of LPS: Low (3.3 microg/day), High (33.3 microg/day), or Placebo over 90 days, were implanted subcutaneously in 3-month-old male Sprague-Dawley rats (n = 8/group). Neutrophil counts, indicative of ongoing inflammation, were elevated (P < 0.05) in both LPS groups at 30 days post-implant and remained significantly elevated in the High dose throughout the 90-day study period. At the end of the study, bone loss occurred in the femur as indicated by decreased bone mineral density (BMD) in both LPS-treated groups, but vertebral BMD was reduced in the High dose animals only. Microcomputed tomography revealed that trabecular bone volume (BV/TV) of the proximal tibial metaphysis tended to be reduced in the High dose LPS group. Deleterious effects on trabecular number (TbN) and trabecular separation (TbSp) were observed in both LPS-treated groups, but only the High dose group reached statistical significance. These alterations in trabecular microarchitecture resulted in compromised biomechanical properties. No changes in cortical thickness, porosity, or area of the tibia midshaft were evident at either dose of LPS. Up-regulation of the proinflammatory mediators, cyclooxygenase (COX)-2, interleukin (IL)-1, and tumor necrosis factor (TNF)-alpha was demonstrated in the metaphyseal region where the deleterious effects of LPS were observed. In addition to these alterations in bone, trichrome staining indicated changes in the coronary arterioles, consistent with vascular disease. Utilization of a LPS time-release pellet appears to provide an in vivo model of chronic inflammation-induced bone loss and a potentially novel system to study concurrent development of osteopenia and vascular disease.

Recomendaciones de GEAM/SPNS sobre el tratamiento de las alteraciones metabólicas y morfológicas en el paciente con infección por VIH

OBJECTIVE

To provide an update of the metabolic and morphologic alterations in patients infected with HIV with an in-depth analysis of their clinical management and treatment.

METHODS

These recommendations were agreed by consensus by a committee of experts in metabolic alterations and HIV patient care, under the auspices of the Secretariat for the National AIDS Plan. To do this, the latest clinical, epidemiological and physiopathological advances described in studies published in the scientific literature and/or presented in congresses were reviewed.

RESULTS

The most frequent metabolic alterations in HIV patients and in antiretroviral treatment (ART) are dyslipidemia with an atherogenic profile and alterations in carbohydrate metabolism/insulin resistance. A high prevalence of cardiovascular risk factors, especially smoking, has been described. The same criteria for their management as those used in the general population have been employed, with specific nuances. Diet and exercise should be the first therapeutic recommendation. In patients with dyslipidemia who require drug treatment, statins and/or fibrates are indicated. Glitazones have demonstrated efficacy in the treatment of insulin resistance. The approach to anomalous fat distribution continues to be controversial. The main approaches at present are a switch of ART, reparative surgery, psychological support and lifestyle changes. Lactic acidosis is an infrequent but highly serious complication, and the first step is withdrawal of ART. In bone metabolism alterations, prevention and early detection are essential, especially in children and perimenopausal women. Sexual dysfunction is a frequent problem in both men and women; because the causes are highly varied, treatment should be individualized.

CONCLUSIONS

The prevalence of metabolic and morphologic alterations has increased since the introduction of highly active antiretroviral treatment (HAART). Knowledge of the various aspects involved in their diagnosis and treatment is essential for the appropriate care of patients with HIV infection.

Maldaptation of the link between inflammation and bone turnover may be a key determinant of osteoporosis

Currently the etiology of osteoporosis is attributed to various endocrine, metabolic, and mechanical factors. We hypothesize that many cases of osteoporosis are also partially attributable to a maladaptation of the link between inflammation and bone turnover. We explore the spatial and temporal link between inflammation and osteoporosis in conditions such as aging, menopause, reflex sympathetic dystrophy, HIV, pregnancy, transplantation, and steroid administration. While nutritional and mechanical factors clearly play a role in many of these situations, the spatial and temporal concordance of osteoporosis and inflammation is buttressed by emerging molecular evidence. Modern bone biology of humans may reflect dual functional legacies of mineral storage and structural support. Osteoporosis may result from disequilibrium between structural demand for key minerals and their biologic demand during maladaptive states of inflammation.

Possible involvement of pregnane X receptor-enhanced CYP24 expression in drug-induced osteomalacia

Vitamin D controls calcium homeostasis and the development and maintenance of bones through vitamin D receptor activation. Prolonged therapy with rifampicin or phenobarbital has been shown to cause vitamin D deficiency or osteomalacia, particularly in patients with marginal vitamin D stores. However, the molecular mechanism of this process is unknown. Here we show that these drugs lead to the upregulation of 25-hydroxyvitamin D(3)-24-hydroxylase (CYP24) gene expression through the activation of the nuclear receptor pregnane X receptor (PXR; NR1I2). CYP24 is a mitochondrial enzyme responsible for inactivating vitamin D metabolites. CYP24 mRNA is upregulated in vivo in mice by pregnenolone 16alpha-carbonitrile and dexamethasone, 2 murine PXR agonists, and in vitro in human hepatocytes by rifampicin and hyperforin, 2 human PXR agonists. Moreover, rifampicin increased 24-hydroxylase activity in these cells, while, in vivo in mice, pregnenolone 16alpha-carbonitrile increased the plasma concentration of 24,25-dihydroxyvitamin D(3). Transfection of PXR in human embryonic kidney cells resulted in rifampicin-mediated induction of CYP24 mRNA. Analysis of the human CYP24 promoter showed that PXR transactivates the sequence between -326 and -142. We demonstrated that PXR binds to and transactivates the 2 proximal vitamin D-responsive elements of the human CYP24 promoter. These data suggest that xenobiotics and drugs can modulate CYP24 gene expression and alter vitamin D(3) hormonal activity and calcium homeostasis through the activation of PXR.