Evaluation of the effects of oxandrolone on malnourished HIV-positive pediatric patients

Steroid myopathy and rehabilitation in patients with cancer

Steroids are broadly used in oncology, despite known adverse events such as glucocorticosteroid-induced myopathy (SM). To date there are no accepted guidelines on the diagnosis and treatment of SM. The purpose of this review is to provide up-to-date information regarding SM with emphasis on neuro-oncology and hematopoietic stem cell transplant patients, given they are at high risk of experiencing SM following routine treatment with steroids. Our work is a combination of a comprehensive narrative review regarding etiology, pathogenesis, incidence, clinical presentation and treatment options for SM and a scoping review on exercise therapy for SM. We have identified 24 in vivo studies of different exercise modalities in the settings of glucocorticosteroid treatment. Twenty of 24 studies demonstrated decreased muscle catabolism with exercise training. Both endurance and resistance exercises at mild to moderate intensity were beneficial. The value of high-intensity activities remains questionable as it may worsen muscle atrophy. Rehabilitation interventions, along with pharmacologic and dietary considerations, may be beneficial in preventing or reversing SM. Potential adverse events of some of these interventions and expected caveats in translating findings in preclinical models to human settings warrant caution and demand controlled clinical studies.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Fast and Sensitive Screening of Oxandrolone and Its Major Metabolite 17-Epi-Oxandrolone in Human Urine by UHPLC-MS/MS with On-Line SPE Sample Pretreatment

Oxandrolone, a synthetic testosterone analog, is used for the treatment of several diseases associated with weight loss. Unfortunately, oxandrolone is abused by many athletes and bodybuilders due to its strong anabolic effect. We have developed and validated a highly sensitive and rapid on-line SPE-UHPLC-MS/MS method for the determination of oxandrolone and simultaneous identification of its major metabolite 17-epi-oxandrolone in urine matrices. Enrichment of the analytes via an integrated solid-phase extraction was achieved using an Acquity UPLC BEH C18 Column. Subsequently, the chromatographic separation of the on-line preconcentrated sample fraction was achieved using an Acquity HSS T3 C18 Column. For the structural identification of these analytes, a high-resolution mass spectrometer Synapt-G2Si coupled to the Acquity M-class nano-LC system with ionKey source was used. A highly sensitive determination of oxandrolone was achieved using a tandem quadrupole mass spectrometer XEVO TQD. The method was successfully validated in the linear range of oxandrolone from 81.63 pg·mL⁻¹ (limit of quantification, LOQ) to 5000 pg·mL⁻¹ in the human urine matrix. It was applied to the analysis of real urine samples obtained from a healthy volunteer after the oral administration of one dose (10 mg) of oxandrolone. Concentration vs. time dependence was tested in the time interval of 4 h–12 days (after oral administration) to demonstrate the ability of the method to detect the renal elimination of oxandrolone from the human body. Favorable performance parameters along with successful application indicate the usefulness of the proposed method for its routine use in antidoping control labs.

Stability of Oxandrolone in Medium-Chain Triglyceride Oil and Pharmacokinetics Following Buccal Administration of the Extemporaneous Formulation in Neonates and Adults

OBJECTIVES Growth failure following surgical palliation of complex congenital heart defects (CHDs) is a prognosticator of poor outcomes. Many strategies for improving weight gain have been implemented in this population, with limited success. We recently described the potential of the anabolic steroid oxandrolone to improve weight gain following surgical repair of CHD when administered via a medium-chain triglyceride (MCT) oil suspension to the buccal mucosa. The current study evaluates the stability of oxandrolone in the MCT oil formulation, as well as the pharmacokinetics of oxandrolone when administered via buccal mucosa in both neonates and adults.

METHODS Stability was assessed by long-term storage of the preparation 1) at ambient conditions and 2) under photodegradative conditions for 3 days. Neonatal pharmacokinetic parameters were determined in a cohort of neonates following surgical CHD repair, whereas adult pharmacokinetics parameters were collected as part of a prospective study to evaluate the relative bioavailability of the oxandrolone in MCT oil formulation.

RESULTS We found that oxandrolone was stable in the MCT oil formulation for at least 1 month, although exposure to light hastened drug degradation. Both neonatal and adult oxandrolone pharmacokinetics were variable; however, oxandrolone in MCT oil was relatively well absorbed through the buccal mucosa (mean bioavailability = 62.5%).

CONCLUSIONS These data suggest that the variability in oxandrolone exposures is inherent to the drug, and not the formulation or route of administration. Combined, these data support further study of this novel oxandrolone in MCT oil formulation and its impact on growth following complex surgical repair of CHD in neonates.

Androgen Treatment Effects on Motor Function, Cognition, and Behavior in Boys with Klinefelter Syndrome

OBJECTIVES

To examine the effects of early low-dose androgen on motor, cognitive, and behavioral function in prepubertal boys with Klinefelter syndrome (47,XXY).

STUDY DESIGN

Double-blind trial of 84 boys, ages 4-12 years, randomized to oxandrolone (Ox; 0.06?mg/kg daily; n?=?43) or placebo (Pl; n?=?41) for 24 months. Standardized assessments were performed at baseline and every 12 months for 24 months evaluating motor, cognitive, and behavioral function.

RESULTS

The 24-month outcomes were better in the Ox vs. Pl group on 1 of 5 primary endpoints (motor function/strength): Bruininks Visual-Motor scale (P?=?.005), without significant differences between the 2 groups for the other 4 components. Secondary analyses suggested improvement in the Ox vs. Pl group in the anxiety/depression (P?=?.03) and social problems (P?=?.01) scales on the Child Behavior Checklist, anxiety (P?=?.04) on the Piers Harris Self Concept Scale, and interpersonal problems (P?=?.02) on the Children's Depression Inventory, without significant differences in hyperactive or aggressive behaviors.

CONCLUSIONS

This double-blind, randomized trial demonstrates that 24 months of childhood low-dose androgen treatment in boys with Klinefelter syndrome benefited 1 of 5 primary endpoints (visual-motor function). Secondary analyses demonstrated positive effects of androgen on aspects of psychosocial function (anxiety, depression, social problems), without significant effects on cognitive function, or hyperactive or aggressive behaviors.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00348946.

Use and Effectiveness of Performance-Enhancing Substances

The use and effects of selected performance-enhancing drugs and nutritional supplements are reviewed. Recent sports medicine studies are mostly double blind and placebo controlled but contain relatively small sample sizes. Their data appear reliable and are reported in reputable journals. Definitions and methods used in sports medicine are provided to enhance the understanding of this literature. The use of performance-enhancing substances is probably under-reported. Anabolic-androgenic steroids are reportedly used in 0% to 1% of women, 0.5% to 3% of high school girls, 1% to 5% of men, 1% to 12% of high school boys, and up to 67% of some groups of elite athletes. The use of combinations of performance-enhancing substances is common. Carbohydrate loading, adequate protein intake, creatine, blood doping, and erythropoietin (epoetin alfa) appear to enhance performance. Anabolic-androgenic steroids enhance performance, but health risks limit their use. Growth hormones and β2 -selective adrenergic agonists may enhance performance, but additional studies are needed. Androstenedione, caffeine, amphetamines, and nonprescription sympathomimetics do not appear to enhance performance. Performance-enhancing drugs have shown some benefit in diseased patients with malnutrition and/or decreases in physical ability. Pharmacists and other health care providers have opportunities to improve the understanding, use, and monitoring of performance-enhancing substances.

Use of Oxandrolone to Promote Growth in Neonates following Surgery for Complex Congenital Heart Disease: An Open-Label Pilot Trial

OBJECTIVE

Malnutrition and poor weight gain, common in neonates following repair of complex congenital heart disease (CHD), are associated with increased morbidity and mortality. Oxandrolone, an anabolic steroid, improves weight gain in older children at high-risk for growth failure. We sought to determine feasibility, safety, and efficacy of oxandrolone therapy in neonates following surgery for complex CHD.

DESIGN

Neonates with RACHS-1 score >3 were eligible to receive open-label oxandrolone for 28 days in this prospective pilot trial. There were 3 cohorts of 5 subjects receiving oxandrolone therapy under 3 specified dosage and preparation protocols: 0.1 mg/kg/day aqueous solution, 0.2 mg/kg/day aqueous solution, and 0.1 mg/kg/day preparation in medium chain triglyceride (MCT) oil. Age- and diagnosis-matched neonates who underwent surgery, but received no oxandrolone, served as a control cohort. Anthropometric measurements, physical examination for virilization, safety labs, and adverse events were monitored.

RESULTS

Of 25 eligible patients, 15 consented (60%, 13/15 with Norwood procedure). There was no evidence of virilization, no changes in safety labs, and no serious adverse events related to oxandrolone among subjects receiving therapy. No subject met criteria for termination of study drug. There was a significant difference in change in weight-for-age z-score among the four cohorts, with subjects receiving 0.1 mg/kg/day in MCT oil having the lowest decline during the study period (-1.8 ± 0.5 for controls, -1.7 ± 0.4 for 0.1 mg/kg/day aqueous, -1.0 ± 0.4 for 0.2 mg/kg/day aqueous, and -0.6 ± 0.7 for 0.1 mg/kg/day MCT oil, P = .012).

CONCLUSIONS

Oxandrolone therapy at the doses studied appears safe in neonates after surgery for complex CHD. The decline in weight-for-age z-score was lowest in those receiving the MCT oil preparation suggesting better bioavailability of this preparation and a potential growth benefit with oxandrolone therapy. Further investigation is needed to define optimal dosing and assess efficacy.

Quantitative Assay Validation for Oxandrolone in Human Plasma Using LC-MS-MS

A high-performance liquid chromatography-tandem mass spectrometry (LC-MS-MS) method for the determination of oxandrolone concentration in human plasma (0.5 mL) was developed and validated according to the 2001 FDA Bioanalytical Guidelines. Oxandrolone is an anabolic steroid used to promote weight gain for cachectic patients with severe burn injuries, HIV/AIDS, hepatitis C and other wasting syndromes. The assay procedure involved a liquid-liquid extraction of oxandrolone and methyltestosterone (the internal standard, IS) from plasma with n-butyl chloride. The organic layer was clarified by centrifugation and evaporated to dryness under a stream of air. The residue was reconstituted in a solution containing 25% methanol and 75% Milli-Q water, and injected onto a Luna C18 reversed-phase HPLC column (30 mm × 2.0 mm, 2 μm). Separation of oxandrolone and methyltestosterone was achieved with a mobile phase starting composition of 55% methanol and 45% ammonium formate buffer at a flow rate of 0.1 mL/min. The total run time was 21 min per sample. Selected reaction monitoring mode was used for quantifying oxandrolone (m/z 307 → 271) and the IS, methyltestosterone (m/z 301 → 149). To the authors' knowledge, this is the first LC-MS-MS method validated for oxandrolone quantification in human plasma. This method can be used in future pharmacokinetic studies involving oxandrolone.

Endocrinopathies in children infected with human immunodeficiency virus

Endocrine changes (including adrenal insufficiency, disorders of growth and puberty, thyroid dysfunction, metabolic abnormalities and osteopenia) accompany human immunodeficiency virus (HIV) infection in pediatric patients. The cause of these changes is multifactorial and includes direct viral effects of HIV, and effects of antiretroviral therapy. These effects may be of particular importance in childhood given the critical developmental processes that occur during this time period and the likelihood of prolonged exposure to the virus and medications.

Oxandrolone for the treatment of bone marrow failure in Fanconi anemia

BACKGROUND

A majority of Fanconi anemia (FA) patients will experience bone marrow failure (BMF) and androgen therapy (most often oxymetholone) may be utilized as a treatment to improve BMF-related cytopenias. However, oxymetholone is associated with toxicities making identification of other agents of interest. In this study we aimed to evaluate the toxicity profile and hematologic response in patients with FA who are treated with low-dose oxandrolone, a synthetic non-fluorinated anabolic steroid, similar to oxymetholone, with known dosing thresholds for virilization.

PROCEDURE

A single arm, Phase I/II study was designed to treat patients on low-dose oxandrolone. If no toxicity or hematologic response was noted at 16 weeks, a single dose escalation was offered. Subjects were regularly assessed for toxicity, including determinations of virilization, behavioral changes, and liver and kidney function. At 32 weeks, those who demonstrated hematologic response were allowed to continue study treatment, and those without improvement were deemed non-responsive.

RESULTS

Nine subjects completed the study and were followed for a median of 99 weeks (46-136 weeks). Three (33.3%) subjects developed mild sub-clinical virilization and continued treatment with a dose reduction. None (0%) had adverse behavioral changes. Two (22.2%) developed elevated liver function tests at 42 and 105 weeks. Seven (77.8%) subjects had a hematologic response.

CONCLUSION

Oxandrolone appears to be well-tolerated, has limited toxicities at the administered doses in FA with patients, and may be an alternative androgen for the treatment of BMF in FA.

Anabolic-androgenic steroids: use and abuse in pediatric patients

The "win at all costs" mentality fuels athletes to seek performance-enhancing substances, such as anabolic-androgenic steroids, to gain an advantage over their opponents. Nonathletes espouse this same attitude to "win" the battle of attractiveness. An enhanced understanding of anabolic-androgenic steroids and the motivations behind their abuse will arm pediatricians with the ability to engage their patients in a balanced discussion of the benefits and costly risks of anabolic-androgenic steroids and successfully deter further use.

Anabolic steroids for the treatment of weight loss in HIV-infected individuals

BACKGROUND

Individuals with HIV infection often lose weight during the course of their disease. Furthermore, low serum concentrations of testosterone are common in individuals with HIV infection, particularly those with weight loss. Treatment of weight loss with anabolic steroids in HIV-infected individuals may be beneficial.

OBJECTIVES

Our objectives were to assess the efficacy and safety of anabolic steroids for the treatment of weight loss in adults with HIV infection.

SEARCH STRATEGY

We searched the following databases: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, AIDSLINE, AIDSearch, EMBASE, CINAHL, Current Contents, and the National Library of Medicine Gateway Abstracts for controlled trials up to April 2005. We also searched the bibliographies of the identified studies and review the articles. In addition, pharmaceutical manufacturers of anabolic steroids were contacted.

SELECTION CRITERIA

Randomized controlled trials that compared the use of an anabolic steroid to placebo to treat weight loss in adults with HIV were included. Randomized controlled trials that compared the use of anabolic steroids to placebo for the treatment of weight loss in adults with HIV were selected. Change from baseline in lean body mass or in body weight was reported as on outcome measure.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed the trials for quality of randomization, blinding, withdrawals, and adequacy of allocation concealment. For continuous data, weighted mean differences (WMD) were calculated. For dichotomous outcomes, risk differences, were calculated. Because of uncertainty as to whether consistent true effects exist in such different populations and treatments, the authors decided a priori to use random effects models for all outcomes.

MAIN RESULTS

Thirteen trials met the inclusion criteria. Two hundred ninety-four individuals randomized to anabolic steroid therapy and 238 individuals randomized to placebo were included in the analysis of efficacy for change from baseline in lean body mass. Three hundred forty-three individuals randomized to anabolic steroid and 286 randomized to placebo were included in the analysis of efficacy for change from baseline in body weight. The mean methodologic quality of the included studies was 4.1, of a maximum 5 points. Although significant heterogeneity was present for both outcomes, the average change in lean body mass was 1.3 kg (95% CI: 0.6, 2.0), while the average change in total body weight was 1.1 kg (95% CI: 0.3, 2.0). A total of eight deaths occurred during the treatment period; four in the anabolic steroid treatment groups and four in the placebo-treatment groups (risk difference 0.00, 95% CI -0.03, 0.03). The risk difference for withdrawals or discontinuations of study medication due to adverse events was 0.00 (95% CI: -0.02, 0.03).

AUTHORS' CONCLUSIONS

Although the results of the trials were heterogeneous, on average, the administration of anabolic steroids appeared to result in a small increase in both lean body mass and body weight as compared with placebo. While these results suggest that anabolic steroids may be useful in the treatment of weight loss in HIV infected individuals, due to limitations, treatment recommendations cannot be made. Further information is required regarding the long-term benefit and adverse effects of anabolic steroid use, the specific populations for which anabolic steroid therapy may be most beneficial, and the optimal regime. In addition, the correlation of improvement in lean body mass with more clinically relevant endpoints, such as physical functioning and survival, needs to be determined.

The anabolic androgenic steroid oxandrolone in the treatment of wasting and catabolic disorders: review of efficacy and safety

There has been increasing interest in the development of effective agents that can be safely used to promote anabolism in the clinical setting for patients with chronic wasting conditions as well as in the prevention and treatment of frailty associated with loss of muscle tissue in aging (sarcopenia). One such agent is the anabolic androgenic steroid (AAS) oxandrolone, which has been used in such clinical situations as HIV-related muscle wasting, severe burn injury, trauma following major surgery, neuromuscular disorders and alcoholic hepatitis for over 30 years. In the US, oxandrolone is the only AAS that is US FDA-approved for restitution of weight loss after severe trauma, major surgery or infections, malnutrition due to alcoholic cirrhosis, and Duchenne's or Becker's muscular dystrophy. Our review of the use of oxandrolone in the treatment of catabolic disorders, HIV and AIDS-related wasting, neuromuscular and other disorders provides strong evidence of its clinical efficacy. Improvements in body composition, muscle strength and function, status of underlying disease or recovery from acute catabolic injury and nutritional status are significant in the vast majority of well designed trials. However, oxandrolone has not yet been studied in sarcopenia.Unlike other orally administered C17alpha-alkylated AASs, the novel chemical configuration of oxandrolone confers a resistance to liver metabolism as well as marked anabolic activity. In addition, oxandrolone appears not to exhibit the serious hepatotoxic effects (jaundice, cholestatic hepatitis, peliosis hepatis, hyperplasias and neoplasms) attributed to the C17alpha-alkylated AASs. Oxandrolone is reported to be generally well tolerated and the most commonly documented adverse effects are transient elevations in transaminase levels and reductions in high density lipoprotein cholesterol level.However, optimal risk:benefit ratios for oxandrolone and other agents in its class will need to be refined before widespread clinical acceptance of AASs as a therapeutic option in sarcopenia and other chronic wasting conditions.

Oxandrolone treatment of childhood hereditary angioedema

BACKGROUND

The virilizing effects of danazol, stanozolol, and methyltestosterone significantly restrict the usefulness of these agents in the treatment of children with hereditary angioedema (HAE). Oxandrolone is a synthetic anabolic steroid with limited virilizing effects that has been used in a variety of pediatric conditions and has an acceptable safety profile.

OBJECTIVE

To report the effective use of oxandrolone in a 6-year-old boy with recurrent, life-threatening episodes of angioedema.

METHODS

Oxandrolone was administered at a dose of 0.1 mg/kg per day. Symptoms and laboratory findings were evaluated by parental report and laboratory analysis of serum C1 esterase inhibitor and C4 levels, respectively.

RESULTS

Oxandrolone therapy resulted in a marked reduction in clinical episodes and normalization of serum complement levels; cessation of oxandrolone therapy resulted in recurrence of symptoms and decreased complement levels. However, early signs of virilization were noted.

CONCLUSIONS

Oxandrolone treatment was associated with significant clinical and laboratory evidence of a therapeutic effect in a prepuberal boy with HAE. It is imperative to treat HAE with the lowest dose of oxandrolone that controls life-threatening episodes of angioedema.

Nutritional aspects of HIV-infected children receiving highly active antiretroviral therapy

The presentation of the nutritional problems of HIV-infected children is changing over time with improved antiretroviral regimens. Early reports of HIV infection in the 1980s, included such problems as malnutrition and wasting. However, as treatment and prophylactic regimens improve, the current nutritional problems of HIV-infected children in developed countries include truncal obesity and insulin resistance in addition to malnutrition. Background data on the wasting syndrome, etiology of malnutrition, nutritional effects of highly active antiretroviral therapies, and nutritional intervention strategies for HIV-infected children will be presented.

General nutrition management in patients infected with human immunodeficiency virus

Nutritional management is integral to the care of all patients infected with human immunodeficiency virus (HIV). HIV infection results in complicated nutritional issues for patients, and there is growing evidence that nutritional interventions influence health outcomes in HIV-infected patients. We define levels of nutritional care, and we discuss when patients should be referred to providers (i.e., registered dietitians) with nutritional and HIV expertise.

Metabolic complications of antiretroviral therapy in children

Survival in HIV-infected children has greatly improved with the introduction of highly active antiretroviral therapy. Children are more vulnerable than adults to metabolic side effects of therapy because of its potential impact on growth and the children's likely greater cumulative exposure. This review summarizes the epidemiology and management of lipodystrophy, dyslipidemia, insulin resistance, hyperlactatemia, osteopenia and growth failure in HIV-infected children.

Orexigenic and anabolic agents

Anorexia and weight loss represent a major cause of morbidity and mortality. At present in the United States two effective anorectic agents are commonly used, namely, megestrol acetate and dronabinol. These two agents are compared in Table 1. In persons with a large excess cytokine production. megestrol acetate should be tried at a does of 800 mg per day for no longer than 3 months. Megestrol acetate should be administered with testosterone in men. It should be avoided in persons who are bed-bound because of the risk of deep vein thrombosis. Dronabinol should be used for most anorectic patients. Dronabinol should initially be given in a low dose (2.5 mg) in the evening. The dose should be increased to 5 mg per day if no improvement in appetite is seen after 2 to 4 weeks. Dronabinol can be continued indefinitely. It seems to have a particularly good profile for persons with anorexia who are at the end of life. In persons with depression and anorexia. mirtazapine seems to be the antidepressant of choice. In addition, the use of taste enhancers can be considered in persons who complain that the food does not taste good. The appropriate use of anabolic agents in older persons with weight loss is controversial. Certainly all older men who are losing weight should have bioavailable testosterone measured and, if the testosterone level is low, should receive testosterone replacement therapy. Women who are losing weight may benefit from the use of low-dose testosterone (eg, Estratest). Anabolic agents, such as oxandrolone, should be reserved for those who have profound cachexia. An approach to the management of anorexia and weight loss in older persons is given in Fig. 1. Thomas et al have provided a more complex algorithm the management of weight loss in nursing home residents.

Update on Anabolic Agents

Nutrition Support Consultant features issues pertinent to the clinical aspects of pharmacy nutritional support practice.

Sarcopenia

Sarcopenia is a term utilized to define the loss of muscle mass and strength that occurs with aging. Sarcopenia is believed to play a major role in the pathogenesis of frailty and functional impairment that occurs with old age. Progressive muscle wasting occurs with aging. The prevalence of clinically significant sarcopenia is estimated to range from 8.8% in young old women to 17.5% in old old men. Persons who are obese and sarcopenic (the "fat frail") have worse outcomes than those who are sarcopenic and non-obese. There is a disproportionate atrophy of type IIa muscle fibers with aging. There is also evidence of an age-related decrease in the synthesis rate of myosin heavy chain proteins, the major anabolic protein. Motor units innervating muscle decline with aging, and there is increased irregularity of muscle unit firing. There are indications that cytokines-especially interleukin-1beta, tumor necrosis factor-alpha, and interleukin-6-play a role in the pathogenesis of sarcopenia. Similarly, the decline in anabolic hormones-namely, testosterone, dehydroepiandrosterone growth hormone, and insulin-like growth factor-I-is also implicated in the sarcopenic process. The role of the physiologic anorexia of aging remains to be determined. Decreased physical activity with aging appears to be the key factor involved in producing sarcopenia. An increased research emphasis on the factors involved in the pathogenesis of sarcopenia is needed.

HIV disease in children. The many ways it differs from the disease in adults

HIV infects and affects children differently than it does adults. An understanding of the epidemiology of pediatric HIV infection may reveal opportunities to reduce and perhaps eliminate perinatal transmission. Knowledge of unique diagnostic features of HIV-exposed newborns and pathogenetic characteristics reflected in clinical manifestations helps physicians meet the management challenges presented by children with HIV and their families.