Easing the transition of HIV-infected adolescents to adult care

The past two decades have witnessed dramatic reductions in HIV-related morbidity and mortality following the introduction of combination antiretroviral therapy (cART) for infants and children. Improved therapeutic outcomes have changed the face of the HIV epidemic and with it the needs of patients and families. Consequently, many perinatally- and behaviorally-infected adolescents are now transitioning to adult care. What follows is a brief review and commentary concerning original research, reviews, and clinical guidelines describing challenges and best practices in facilitating care transitions for HIV-infected youth to adult care. Over 25,000 HIV-infected US youth aged 13-24 years will require transition to adult care within the next decade. Transition planning must address issues of cognitive development and mental health, medication adherence, sexuality, reproductive, and gender identity, socioeconomic and health insurance status, stigma and disclosure, disrupted relationships with pediatric care providers, and communication. Clinical experience with HIV and other chronic illnesses supports a multidisciplinary, developmentally-sensitive approach to meeting the challenges inherent in care transition that begins early and is monitored with regular evaluation and revision. Specific clinical recommendations have been made by the U.S. Department of Health and Human Services and the New York State Department of Health AIDS Institute.

Predictors of growth and body composition in HIV-infected children beginning or changing antiretroviral therapy

OBJECTIVES

The aim of the study was to describe growth and body composition changes in HIV-positive children after they had initiated or changed antiretroviral therapy (ART) and to correlate these with viral, immune and treatment parameters.

METHODS

Ninety-seven prepubertal HIV-positive children were observed over 48 weeks upon beginning or changing ART. Anthropometry and bioelectrical impedance analysis results were compared with results from the National Health and Nutrition Examination Survey 1999-2002 (NHANES) to generate z-scores and with results for HIV-exposed, uninfected children from the Women and Infants Transmission Study (WITS). Multivariate analysis was used to evaluate associations between growth and body composition and disease parameters.

RESULTS

All baseline lean and fat mass measures were below those of controls from NHANES. Weight, height and fat free mass (FFM) index (FFM/height(2)) z-scores increased over time (P = 0.004, 0.037 and 0.027, respectively) and the waist:height ratio z-score decreased (P = 0.045), but body mass index and per cent body fat z-scores did not change. Measures did not increase more than in uninfected WITS controls. In multivariate analysis, baseline height, mid-thigh circumference and FFM z-scores related to CD4 percentage (P = 0.029, P = 0.008 and 0.020, respectively) and change in FFM and FFM index z-scores to CD4 percentage increase (P = 0.010 and 0.011, respectively). Compared with WITS controls, baseline differences in height and mid-thigh muscle circumference were also associated with CD4 percentage. Case-control differences in change in both subscapular skinfold (SSF) thickness and the SSF:triceps skinfold ratio were inversely associated with viral suppression. No measures related to ART class(es) at baseline or over time.

CONCLUSIONS

In these HIV-positive children, beginning or changing ART was associated with improved growth and lean body mass (LBM), as indicated by FFM index. Height and LBM related to CD4 percentage at baseline and over time. Altered fat distribution and greater central adiposity were associated with detectable virus but not ART class(es) received.

Preventive efficacy and cost-effectiveness of point-of-use water filtration in a subacute care unit

Infections with Pseudomonas aeruginosa and other waterborne pathogens (WBPs) are major contributors to serious morbidity and mortality in hospitals. We sought to determine whether point-of-use (POU) water filtration might result in decreased risk of infection in the subacute care unit (SACU) of a 208-bed medical center. Our findings indicate that POU water filtration can significantly and cost-effectively reduce colonization of and infection with WBPs, including ventilator-associated pneumonia, in an SACU.

Lipid and glucose alterations in HIV-infected children beginning or changing antiretroviral therapy

OBJECTIVE

The objective of this study was to describe lipid profiles and glucose homeostasis in HIV-positive children after initiating or changing antiretroviral therapy and their associations with viral, immune, antiretroviral therapy, and growth factor parameters.

METHODS

Ninety-seven prepubertal HIV-positive children aged 1 month to <13 years were observed for 48 weeks after beginning or changing antiretroviral therapy. Fasting lipid panels, serum glucose, insulin, insulin-like growth factor-1 and binding proteins-1 and -3, plasma viral load, and CD4% were measured. Each child was matched on age, gender, and race/ethnicity to children from the National Health and Nutrition Examination Survey, used to give z scores for each child's lipid values. Multivariate regression was used to evaluate the association of changes in z scores over 48 weeks with suppression of HIV-1 RNA, change in CD4% and growth factors, and antiretroviral therapy, adjusted for entry z score, CD4%, log(10) HIV-1 RNA, Centers for Disease Control and Prevention category, and total fat and cholesterol dietary intake.

RESULTS

Lipid, apolipoprotein, and insulin levels all increased significantly by 48 weeks. Multivariate analysis of changes demonstrated that increased HDL and decreased total-HDL cholesterol ratio were associated with CD4% increase and with insulin-like growth factor-1, which increased to normal (versus remained stable or became low) over 48 weeks. Total cholesterol levels increased among children who achieved HIV-1 RNA of <400 copies per mL. Antiretroviral therapy regimens that included both a protease inhibitor and a non-nucleoside reverse transcriptase inhibitor were associated with greater increases in total-HDL cholesterol ratio than regimens that contained a protease inhibitor or a non-nucleoside reverse transcriptase inhibitor but not both.

CONCLUSIONS

In these HIV-positive children with predominantly mild-to-moderate disease, initiation or change in antiretroviral therapy was associated with significant increases in multiple lipid measures and insulin resistance. Favorable lipid changes were associated with CD4% increases, suggesting a protective effect of immune reconstitution on atherosclerosis, and with increased insulin-like growth factor-1 levels, supporting the theory that reduced growth hormone resistance may be a mechanism by which lipid profiles are improved. Finally, antiretroviral therapy regimens that contain both a non-nucleoside reverse transcriptase inhibitor and a protease inhibitor are associated with worse lipid profiles than regimens that contain 1 but not both of these drug classes.

Filters reduce the risk of bacterial transmission from contaminated heated humidifiers used with CPAP for obstructive sleep apnea

RATIONALE

The treatment of choice for obstructive sleep apnea (OSA) is nasal continuous positive airway pressure (nCPAP) during sleep, but dryness of the upper airway compromises compliance. Heated humidifiers may mitigate such noncompliance; however, recent observations suggest that their use, particularly if not cleaned, increases the risk of respiratory infections. Humidifier water may be contaminated, but the long-held view that passive humidifiers cannot aerosolize water may obscure the perception of risk of infection.

OBJECTIVES

This study challenges the long-held view that "passover" humidifiers do not aerosolize water. With such evidence, this study characterizes the performance of filters to reduce the potential risk of contamination.

METHODS

Heated humidifier water contaminated with bacteria was studied under conditions simulating week-long use of nCPAP for OSA.

RESULTS

Bacteria were recovered in 9 of 11 tests from the breathing tubes of CPAP devices fitted with heated humidifiers with water contaminated with Brevundimonas diminuta or Serratia marcescens. Recoverable bacteria ranged from tens to thousands of colony forming units when tested at air flow rates of 60 liters per minute for 90 minutes. Neither organism was recovered from the circuit tubing when a hydrophobic breathing-circuit filter was positioned between the humidifier and face-mask tubing with a commercially available nCPAP machine tested under simulated-use conditions.

CONCLUSION

Data suggest that patients with OSA being treated with nCPAP fitted with humidifiers may be aerosolizing bacteria, putting them at risk for developing respiratory infections and that the use of a hydrophobic filter may attenuate the passage of microbes from contaminated humidifier water.

Leukocyte Reduction's Role in the Attenuation of Infection Risks among Transfusion Recipients

Despite advances in the screening of donated blood for infectious agents, the risk of transmitting viral, bacterial, and protozoal infections, as well as newly emerging diseases, via transfusion persists. A complementary approach is leukocyte reduction (LR), the removal of leukocytes from donated blood by filtration. Published evidence, establishing the benefit of LR in reducing the risk of febrile nonhemolytic reactions, cytomegalovirus transmission, and human leukocyte antigen alloimmunization has led to its use for some time for the care of immunosuppressed and other individuals considered to be at high risk for such complications. Recent literature suggests that LR may be effective in reducing the risk of transmission of a number of additional transfusion-transmitted infectious agents, including herpesviruses, retroviruses, bacteria, protozoa, and prions. There is also evidence that LR may reduce the risk of transfusion-related immunomodulation, further contributing to protection against infections that would complicate treatment. With the mounting evidence of potential benefit, a number of countries, as well as many hospitals and blood centers in the United States, have adopted a policy of performing LR for all donated blood. Physicians who care for immunosuppressed patients and those who are responsible for institutional infection-control practices should remain informed of the growing body of literature on LR.

An Overview of Prion Biology and the Role of Blood Filtration in Reducing the Risk of Transfusion-Transmitted Variant Creutzfeldt-Jakob Disease

Prions are infectious proteins believed to be responsible for a variety of progressive and fatal neurodegenerative diseases, collectively referred to as transmissible spongiform encephalopathies (TSE). By 1996, it was recognized that ingestion of beef from cattle afflicted with a TSE known as bovine spongiform encephalopathy, could result in a devastating human TSE known as variant Creutzfeldt-Jakob disease (vCJD). Two recent reports of probable transfusion-transmitted vCJD have raised concerns about the safety of the blood supply. The relatively long asymptomatic latency of vCJD, as well as the lack of sensitive and specific antemortem tests, increase the risk that asymptomatic, infected individuals may become blood donors. To this point, donor deferral has been a strategy used to reduce this risk. Nevertheless, this strategy may be unreliable and, furthermore, may threaten blood availability. Leukoreduction has also been helpful in reducing cell-associated infectious prion, which has been reported to reduce up to 42% of the infectivity in blood. Proprietary prion affinity surface modifications have been developed and applied to filters, which exploit an understanding of the unique chemical characteristics of prion surfaces. These have been successfully adapted to existing high-efficiency blood filter matrices for the reduction of prions present in blood components for transfusion.

Prion biology in transfusion medicine: implications for lab testing

Although eerily silent for many years after the recognition of scrapie in 1759, TSEs remained present within the genome of some mammals. Not since the mid-1950s when Dr. Carleton Gadjusek visited the Fore Indians of New Guinea to study kuru, however, has there been a more frenetic interest by governmental investigators. Certainly, the U.K. experience has heralded a renewed interest in TSEs due to the notoriety associated with younger subjects succumbing to a variant CJD traced to the ingestion of beef. Human TSEs and the potential for their transmission among and across species of mammals has also captured the attention of many. Yet, to date, there is no reliable antemortem test available to screen for infected animals or humans. Antibody-based assays are difficult to develop because most of them do not have specificity for the pathogenic form of prion protein. Whether or not prion testing efforts will change dramatically depends upon the incidence of disease. Some speculate a reduction in testing, because BSE incidence is waning since the adoption of remedial steps in the U.K. in 1989. Others remind us, however, of the long latency of prion diseases and of the recent observations of two patients who succumbed to vCJD after having received blood products from donors who subsequently died of vCJD. The growing incidence of CWD, combined with the emerging observation that as many as 26% of Alzheimer's patients may have been misdiagnosed--having died instead of prion disease--maintains pressure for legislators to adhere to the precautionary principle and support blood-donor exclusionary criteria, antemortem-test development, and pathogen removal from donated blood. The laboratorian can expect to see new tests for prion disease work their way into clinical-testing practice in the near future. In addition, the adoption of newer filtration technologies holds the promise of improved protection from transfusion-transmitted prion disease.

Diagnosis and management of infectious esophagitis associated with human immunodeficiency virus infection

Esophageal disease is a common complication and cause of morbidity in patients with human immunodeficiency virus (HIV) infection. Opportunistic infections are the leading cause of esophageal complaints and may be a predictor of poor long-term prognosis, presumably as a reflection of severe underlying HIV immunodeficiency. The esophagus may be the site of the first acquired immunodeficiency syndrome (AIDS)-defining opportunistic illness in a large number of patients. Barium esophagography and upper gastrointestinal endoscopy are diagnostic modalities, commonly used to evaluate esophageal complaints in patients with AIDS. Treatment for most etiologies of esophagitis generally has a high degree of success, with a resultant improvement in quality of life. In addition to optimizing antiretroviral therapy, a thorough diagnostic assessment of every HIV-infected patient with esophageal complaints is warranted, followed by timely and appropriate treatment.

Enfuvirtide (T-20): a novel human immunodeficiency virus type 1 fusion inhibitor

The development of highly active antiretroviral therapy has improved life expectancy and reduced progression to acquired immunodeficiency syndrome in human immunodeficiency virus (HIV)-infected patients. However, resistance to currently available classes of antiretroviral drugs has become a problem, limiting the options for patients with advanced disease who have been heavily treated. Enfuvirtide (T-20; ENF), a synthetic peptide, is the first of a new class of antiretrovirals that block entry of virus into host cells. ENF interferes with conformational changes required for membrane fusion and injection of virus into the host cell. Optimal treatment of HIV infection will likely require combinations of drugs that target novel stages of HIV type 1 entry and replication.

Impact of protease inhibitor-containing combination antiretroviral therapies on height and weight growth in HIV-infected children

OBJECTIVE

To examine beneficial or detrimental effects of protease inhibitor (PI)-containing antiretroviral regimens on height and weight growth in children with human immunodeficiency virus (HIV) infection.

METHODS

A prospective cohort study was conducted of 906 HIV-infected children, from pediatric research clinics in the United States, who were between 3 months and 18 years of age and who had height and weight assessed in 1995 (before introduction of PIs in this population) and at least once more through 1999. Changes in age- and gender-adjusted height and weight growth associated with PI use were assessed.

RESULTS

Compared with a healthy reference population, children were more affected in height (mean z score: -0.90 [18th percentile]) than in weight (mean z score: -0.42 [34th percentile]) at baseline (1995). Two thirds of children received at least 1 PI during 1996 to 1999. In the multivariate mixed effects regression models adjusted for baseline log(10) CD4 cell count, baseline age, gender, and race/ethnicity, the use of PIs was associated with per-year gains of 0.13 z scores in height and 0.05 z scores in weight relative to the expected growth with non-PI-containing regimens (eg, after 1 year of PI use, a representative 6-year-old boy in our study would be approximately 0.7 cm taller and 0.1 kg heavier than if he had not received PIs). No significant differential effects of PIs on height or weight growth according to specific agents or children's sociodemographic or clinical characteristics were found.

CONCLUSIONS

Although the use of PI-containing regimens was not associated with growth retardation, it was associated with only small annual increments in height and weight growth in HIV-infected children.

Characteristics of human immunodeficiency virus-infected children at the time of death: an experience in the 1990s

OBJECTIVE

To describe the changes in the characteristics of human immunodeficiency virus (HIV)-related deaths in children with perinatally acquired infection.

METHODS

A retrospective review of all deaths that occurred in HIV-infected children managed at The New York Hospital-Program for Children with AIDS during a 7-year period from January, 1990, to December, 1996. Differences in the characteristics at death between 15 children who died in 1990 and 10 children who died in 1996 were analyzed.

RESULTS

Fifty-eight deaths in our cohort of HIV-infected children were identified during the 7-year period. The mean age at death was 4.43 years. Sixty-nine percent of children were black, 55% were male and 94% were receiving Medicaid. The mean weight/age Z score was -3.9 and the mean CD4 index was 0.067 with 65% having <50 CD4 cells/microl at the time of death (TOD). The most common organ/organ systems to be involved at the TOD were lung (78%) and central nervous system (61%). Mycobacterium avium complex (MAC) was the most common isolate at the TOD (26%) followed by Pneumocystis carinii (20%) and Pseudomonas aeruginosa (17%). The leading non-infectious cause of death was cardiac failure (9%). Comparison of the characteristics at the TOD between 1990 and 1996 revealed significant differences in mean age (2.1 vs. 9.2 years, P < 0.0001), mean CD4 count index (0.18 vs. 0.02, P < 0.03), mean number of organ/organ system involvement (3.9 vs. 5.9, P < 0.05), percent receiving antiretroviral therapy (33% vs. 70%, P < 0.02), mean number of years receiving antiretroviral therapy (0.88 vs. 3.86 years, P < 0.01), percent receiving P. carinii pneumonia prophylaxis (27% vs. 100%, P < 0.001), percent receiving MAC prophylaxis/therapy (0% vs. 100%, P < 0.0001), and cause of death from P. carinii pneumonia (53% vs. 0%, P < 0.01).

CONCLUSIONS

Compared with children who died in 1990, HIV-infected children who died in 1996 were significantly older, more lymphopenic and more likely to have a greater number of organ system involvements and to have received antiviral therapy and antimicrobial prophylaxis. In 1996 no child died of P. carinii pneumonia. In 1996 MAC and P. aeruginosa were the two most important opportunistic infections causing death. These changes in the characteristics at death will warrant review of resources used in treating these children and may be critical in advising parents and care givers about the prognosis of this chronic infection.

Micronutrient and cytokine interaction in congenital pediatric HIV infection

Malnutrition is a frequent manifestation of HIV infection that has received comparatively little attention despite growing clinical importance with improved treatment and lengthened survival times. Fundamental relationships and mechanisms of HIV viral interaction in nutrient metabolism remain to be established. In an attempt to begin to fill the void of information relative to pediatric HIV infection, we have summarized the extant knowledge with regard to micronutrients and present some of the data from studies performed in our laboratory. Previous studies have shown both that vitamin A deficiency is associated with increased mortality in HIV+ intravenous drug users and that maternal vitamin A deficiency is a risk factor for transmission in congenital exposure. Our most significant finding is that 70% of children congenitally exposed to HIV are vitamin A-deficient in the first months of life compared to age-matched controls whether they are HIV-infected or not. About 25% of our patient population was found to have growth or developmental delay, frequently without other signs of progression and in the presence of an intact T-cell compartment. In addition, we found evidence of cytokine imbalance, specifically elevated plasma levels of TNF which has been implicated in loss of lean body mass. Inflammatory reactions in the mucosa and increased TNF production in association with regional HIV infection may compromise gastrointestinal absorption. Based on the review of the literature and our research findings, it is clear that understanding the interaction between nutrients and both the regional and systemic immune system is vital for intervention and effective nutrient repletion in congenital HIV infection.

Effect of granulocyte-macrophage colony-stimulating factor in experimental visceral leishmaniasis

GM-CSF induces three effects potentially beneficial in visceral leishmaniasis: blood monocyte mobilization, macrophage activation, and amelioration of granulocytopenia. To determine the experimental role and effect of GM-CSF in this intracellular infection, livers from Leishmania donovani-infected BALB/c mice were tested for GM-CSF mRNA expression and mice were treated with anti-GM-CSF antiserum or GM-CSF. L. donovani infection upregulated hepatic GM-CSF mRNA expression by 10-fold, and anti-GM-CSF treatment exacerbated visceral infection and tripled liver parasite burdens 4 wk after challenge. In euthymic mice with established infection, treatment with 1-5 micrograms/d murine GM-CSF induced three dose-related effects: peripheral blood leukocytosis, preferential accumulation of myelomonocytic cells at visceral foci of infection, and leishmanicidal activity comparable to that achieved by IFN-gamma. These effects were either largely or entirely T cell dependent. Treatment with human GM-CSF also induced anti-leishmanial activity but with little effect on peripheral leukocyte number or tissue myelomonocytic cell influx; human G-CSF stimulated marked peripheral granulocytosis and neutrophil tissue accumulation but induced little antileishmanial effect. These results identify a role for endogenous GM-CSF in the initial host defense response to L. donovani, reemphasize the influxing monocyte as an effector cell, and indicate that GM-CSF can be used as an antileishmanial treatment.

Effector role of blood monocytes in experimental visceral leishmaniasis

In BALB/c mice, liver granulomas provoked by visceral infection with intracellular Leishmania donovani are rapidly populated by influxing blood monocytes. To determine the host defense effector role of these mononuclear phagocytes, we treated three populations of infected animals with 5C6, an anti-type 3 complement receptor monoclonal antibody (MAb), which inhibits monocyte recruitment into inflamed tissues. In naive BALB/c mice, injections of 5C6 impaired the initial acquisition of antileishmanial resistance and arrested the development of mature liver granulomas. In sensitized mice with established immunity, both resistance to rechallenge and accelerated granuloma formation were similarly inhibited by MAb administration. Finally, in naive mice, 5C6 MAb also abolished the antileishmanial activity induced by treatment with the macrophage-activating lymphokine gamma interferon. Together, these results suggest a key effector role for the influxing blood monocyte in both initial and established antileishmanial defense and granuloma assembly and in the infected liver as the mononuclear phagocyte target for the antimicrobial effects of gamma interferon.

Septic pulmonary embolism complicating a central venous catheter

Bacteremia is a recognized complication in patients with indwelling central venous catheters. More recently pulmonary embolism in such patients has also been described. Despite abundant clinical experience with these devices, to our knowledge, septic pulmonary embolism has not been reported in adult patients. This case illustrates such a complication.