The changing spectrum of pulmonary disease in patients with HIV infection on antiretroviral therapy

Kaposi sarcoma herpesvirus viral load in bronchoalveolar lavage as a diagnostic marker for pulmonary Kaposi sarcoma

OBJECTIVE

Kaposi sarcoma is a vascular tumor that affects the pulmonary system. However, the diagnosis of airway lesions suggestive of pulmonary Kaposi sarcoma (pKS) is reliant on bronchoscopic visualization. We evaluated the role of Kaposi sarcoma herpesvirus (KSHV) viral load in bronchoalveolar lavage (BAL) as a diagnostic biomarker in patients with bronchoscopic evidence of pKS and evaluated inflammatory cytokine profiles in BAL and blood samples.

DESIGN

In this retrospective study, we evaluated KSHV viral load and cytokine profiles within BAL and blood samples in patients who underwent bronchoscopy for suspected pKS between 2016 and 2021.

METHODS

KSHV viral load and cytokine profiles were obtained from both the circulation and BAL samples collected at the time of bronchoscopy to evaluate compartment-specific characteristics. BAL was centrifuged and stored as cell pellets and KSHV viral load was measured using primers for the KSHV K6 gene regions.

RESULTS

We evaluated 38 BAL samples from 32 patients (30 with HIV co-infection) of whom 23 had pKS. In patients with airway lesions suggestive of pKS, there was higher KSHV viral load (median 3188 vs. 0 copies/10 6 cell equivalent; P  = 0.0047). A BAL KSHV viral load cutoff of 526 copies/10 6 cells had a sensitivity of 72% and specificity of 89% in determining lesions consistent with pKS. Those with pKS also had higher IL-1β and IL-8 levels in BAL. The 3-year survival rate for pKS patients was 55%.

CONCLUSION

KSHV viral load in BAL shows potential for aiding in pKS diagnosis. Patients with pKS also have evidence of cytokine dysregulation in BAL.

Pulmonary symptoms associated with heavy alcohol consumption among people living with HIV: an analysis of the NHANES 1999-2010

AIM

This matched case-control study aimed to provide epidemiologic evidence of increased burden of respiratory symptoms and pulmonary function decline among people living with human immunodeficiency virus (HIV) and a history of heavy alcohol consumption.

METHODS

Cases were participants with HIV (PWH; n = 75, 33%), and controls were participants without HIV (PWoH; n = 150, 67%). PWH were matched to PWoH by age and sex in the ratio of 1:2. Eligible participants responded to the respiratory health National Health and Nutrition Examination Survey questionnaire [prolonged coughs (≥3 months), bringing up of phlegm (≥3 months), and a history of wheezing or whistling in the chest (past year)]. The effects of both alcohol and HIV on participants' pulmonary function were determined using linear regression analysis.

RESULTS

History of heavy alcohol consumption was more prevalent among PWH (40%) compared to PWoH (27%). PWH who had a history of heavy alcohol consumption had a higher prevalence of coughing most days (45% vs. 4%, P = .0010), bringing up phlegm most days (31% vs. 0%, P = .0012), and wheezing or whistling in the chest (40% vs. 20%, P = .058) compared to participants who did not heavily consume alcohol. Furthermore, a history of heavy alcohol consumption was associated with decreased forced expiratory volume (ml) in 1 s/forced vital capacity among PWH (β = - 0.098 95% C.I. -0.16, -0.04, P = .03) after adjusting for having smoked at least 100 cigarettes in life.

CONCLUSION

A history of heavy alcohol use increased respiratory symptoms and suppressed pulmonary function among people living with HIV. This study provides epidemiological evidence of the respiratory symptom burden of people living with HIV who have a history of heavy alcohol consumption.

HIV Increases the Risk of Cigarette Smoke-Induced Emphysema Through MMP-9

BACKGROUND

HIV is associated with an increased risk for emphysema. Matrix metalloproteinase 9 (MMP-9) is a lung tissue remodeling enzyme associated with emphysema. We previously found MMP-9 activity increases with increases in oxidative stress and that HIV increases alveolar oxidative stress. We hypothesized that HIV proteins would increase the risk of cigarette smoke-induced emphysema due to MMP-9.

METHODS

HIV-1 transgenic rats and wild-type littermates were exposed to cigarette smoke or sham for 8 weeks. Lung compliance and histology were assessed. Bronchoalveolar lavage (BAL), primary alveolar macrophages (AM), and serum samples were obtained. A rat alveolar macrophage cell line was exposed to the HIV protein Tat, and MMP-9 levels were assessed by Western immunoblotting. MMP-9 protein expression and activity were assessed in AM from the HIV rat model by ELISA and cytoimmunofluoresence, respectively. Serum from human subjects with and without HIV and tobacco dependence was assessed for MMP-9 levels.

RESULTS

MMP-9 expression was significantly increased in rat alveolar macrophages after Tat exposure. HIV-1 transgenic rats developed emphysema while wild-type littermates did not. MMP-9 expression was also increased in the serum, BAL, and AM of HIV-1 transgenic rats after exposure to cigarette smoke compared with wild-type rats. In parallel, serum samples from HIV+ smokers had higher levels of MMP-9 than subjects without HIV and those who did not smoke.

CONCLUSION

The combination of HIV and cigarette smoke increases MMP-9 expression in experimental rat HIV models and human subjects. HIV and cigarette smoke both induce alveolar oxidative stress and thereby increase MMP-9 activity.

Immunocompromised Host Pneumonia: Definitions and Diagnostic Criteria: An Official American Thoracic Society Workshop Report

Pneumonia imposes a significant clinical burden on people with immunocompromising conditions. Millions of individuals live with compromised immunity because of cytotoxic cancer treatments, biological therapies, organ transplants, inherited and acquired immunodeficiencies, and other immune disorders. Despite broad awareness among clinicians that these patients are at increased risk for developing infectious pneumonia, immunocompromised people are often excluded from pneumonia clinical guidelines and treatment trials. The absence of a widely accepted definition for immunocompromised host pneumonia is a significant knowledge gap that hampers consistent clinical care and research for infectious pneumonia in these vulnerable populations. To address this gap, the American Thoracic Society convened a workshop whose participants had expertise in pulmonary disease, infectious diseases, immunology, genetics, and laboratory medicine, with the goal of defining the entity of immunocompromised host pneumonia and its diagnostic criteria.

Enrichment of the airway microbiome in people living with HIV with potential pathogenic bacteria despite antiretroviral therapy

BACKGROUND

Long-term antiretroviral therapy (ART) enables people living with HIV (PLW-HIV) to be healthier and live longer; though they remain at greater risk of pneumonia and chronic lung disease than the general population. Lung microbial dysbiosis has been shown to contribute to respiratory disease.

METHODS

16S-rRNA gene sequencing on the Miseq-platform and qPCR for typical respiratory pathogens were performed on sputum samples collected from 64 PLW-HIV (median blood CD4 count 676 cells/μL) and 38 HIV-negative participants.

FINDING

Richness and α-diversity as well as the relative-abundance (RA) of the major taxa (RA>1%) were similar between both groups. In unweighted-Unifrac ß-diversity, the samples from PLW-HIV showed greater diversity, in contrast to the HIV negative samples which clustered together. Gut bacterial taxa such as Bilophila and members of Enterobacteriaceae as well as pathogenic respiratory taxa (Staphylococcus, Pseudomonas and Klebsiella) were significantly more frequent in PLW-HIV and almost absent in the HIV-negative group. Carriage of these taxa was correlated with the length of time between HIV diagnosis and initiation of ART (Spearman-rho=0·279, p=0·028).

INTERPRETATION

Although the core airway microbiome was indistinguishable between PLW-HIV on effective ART and HIV-negative participants, PLW-HIV's respiratory microbiome was enriched with potential respiratory pathogens and gut bacteria. The observed differences in PLW-HIV may be due to HIV infection altering the local lung microenvironment to be more permissive to harbour pathogenic bacteria that could contribute to respiratory comorbidities. Prompt start of ART for PLW-HIV may reduce this risk.

Increasing burden of noninfectious lung disease in persons living with HIV: a 7-year study using the French nationwide hospital administrative database

An overall reduction in the incidence of AIDS and a change in the spectrum of lung disease have been noticed in persons living with HIV (PLHIV). Our aim was to provide an epidemiological update regarding the prevalence of lung diseases in PLHIV hospitalised in France.We analysed the prevalence of lung disease in PLHIV hospitalised in France from 2007 to 2013, from the French nationwide hospital medical information database, and assessed the association between HIV and incident noninfectious disease over 4 years of follow-up.A total of 52 091 PLHIV were hospitalised in France between 2007 and 2013. Among PLHIV hospitalised with lung disease, noninfectious lung diseases increased significantly from 45.6% to 54.7% between 2007 and 2013, whereas the proportion of patients with at least one infectious lung disease decreased significantly. In 2010, 10 067 prevalent hospitalised PLHIV were compared with 8 244 682 hospitalised non-PLHIV. In 30-49-year-old patients, HIV infection was associated with chronic obstructive pulmonary disease (COPD), chronic respiratory failure, emphysema, lung fibrosis and pulmonary arterial hypertension (PAH) even after adjustment for smoking.The emergence of noninfectious lung disease, in particular COPD, emphysema, lung fibrosis, PAH and chronic respiratory disease, in PLHIV would justify mass screening in this population.

Pulmonary Infections in Immunocompromised Hosts: Clinical

Pulmonary infections in immunocompromised patients remain a significant contributor to mortality, morbidity, and health care-associated costs in such a vulnerable patient population. Their epidemiology is changing, set forth by new trends in immunosuppressive regimens and also prophylaxis. The host characteristics, presenting clinical symptomatology, along with radiographic patterns, have also evolved. The microbiology diagnostics are now enriched with nonculture methods for better identification of the causative pathogens. Chest imaging remains the cornerstone of the initial workup. Our article will examine the new trends in epidemiology, clinical findings, and diagnostics for immunocompromised patients with pulmonary infections (transplant recipients, neutropenic hosts, HIV-infected patients, and patients with autoimmune conditions). We will also review the differential diagnosis that most of the times includes malignancies and drug or radiation-related toxicities.

Human immunodeficiency virus associated pulmonary conditions leading to hospital admission and the pulmonary rehabilitation services received by patients at two central hospitals in Harare

Objective

Use of highly active antiretroviral therapy has led to marked reductions in the incidence of HIV-associated opportunistic infections but has had comparatively less impact on the incidence of some pulmonary diseases. This study was done to determine the pulmonary conditions leading to hospital admissions in people living with HIV/AIDS at two central hospitals in Zimbabwe and the pulmonary rehabilitation intervention received.

Results

A total of 92 participants were recruited of which 60 (65.2%) were females. The mean age of the participants was 41.3 years (SD = 9.1). The most common pulmonary condition leading to hospital admission was tuberculosis in 53 (57.6%). About 52 (56.6%) of the participants suffered from pulmonary complications in the last 6 months, 48 (92.3%) were admitted and 26 (50.0%) of the participants received physiotherapy treatment during their admission. None of the participants indicated that they once attended an outpatient pulmonary rehabilitation clinic. Respiratory complication is one of the leading causes of morbidity associated with HIV but no pulmonary rehabilitation services are being offered to these patients. There is need for introduction of pulmonary rehabilitation programs for people living with HIV/AIDS in the current setting.

Expression of pIgR in the tracheal mucosa of SHIV/SIV-infected rhesus macaques

Polymeric immunoglobulin receptors (pIgR) are key participants in the formation and secretion of secretory IgA (S-IgA), which is critical for the prevention of microbial infection and colonization in the respiratory system. Although increased respiratory colonization and infections are common in HIV/AIDS, little is known about the expression of pIgR in the airway mucosa of these patients. To address this, the expression levels of pIgR in the tracheal mucosa and lungs of SHIV/SIV-infected rhesus macaques were examined by real-time RTPCR and confocal microscopy. We found that the levels of both PIGR mRNA and pIgR immunoreactivity were lower in the tracheal mucosa of SHIV/SIV-infected rhesus macaques than that in non-infected rhesus macaques, and the difference in pIgR immunoreactivity was statistically significant. IL-17A, which enhances pIgR expression, was also changed in the same direction as that of pIgR. In contrast to changes in the tracheal mucosa, pIgR and IL-17A levels were higher in the lungs of infected rhesus macaques. These results indicated abnormal pIgR expression in SHIV/SIV, and by extension HIV infections, which might partially result from IL-17A alterations and might contribute to the increased microbial colonization and infection related to pulmonary complications in HIV/AIDS.

Bronchiectasis and other chronic lung diseases in adolescents living with HIV

PURPOSE OF REVIEW

The incidence of pulmonary infections has declined dramatically with improved access to antiretroviral therapy (ART) and cotrimoxazole prophylaxis, but chronic lung disease (CLD) is an increasingly recognized but poorly understood complication in adolescents with perinatally acquired HIV.

RECENT FINDINGS

There is a high prevalence of chronic respiratory symptoms, abnormal spirometry and chest radiographic abnormalities among HIV-infected adolescents in sub-Saharan Africa, wherein 90% of the world's HIV-infected children live. The incidence of lymphocytic interstitial pneumonitis, the most common cause of CLD in the pre-ART era, has declined with increased ART access. Small airways disease, particularly constrictive obliterative bronchiolitis and bronchiectasis, are emerging as leading causes of CLD among HIV-infected adolescents in low-income and middle-income countries. Asthma may be more common in high-income settings. Likely risk factors for CLD include recurrent pulmonary infections, air pollution, HIV-related immune dysfunction, and untreated HIV infection, particularly during critical stages of lung development.

SUMMARY

Globally, the importance of HIV-associated CLD as a cause of morbidity and mortality is increasing, especially as survival has improved dramatically with ART and growing numbers of children living with HIV enter adolescence. Further research is urgently needed to elucidate the natural history and pathogenesis of CLD, and to determine optimal screening, diagnostic and treatment strategies.

Risk factors for community-acquired pneumonia among adults in Kenya: a case-control study

BACKGROUND

Pneumonia is a leading cause of morbidity and mortality among adults worldwide; however, the risk factors for community-acquired pneumonia in Africa are not well characterized.

METHODS

The authors recruited 281 cases of community-acquired pneumonia and 1202 hospital controls among patients aged ≥15 years who attended Kilifi District Hospital/Coast Provincial General Hospital in Kenya between 1994 and 6. Cases were admissions with an acute illness with ≥2 respiratory signs and evidence of consolidation on a chest radiograph. Controls were patients without signs of pneumonia, frequency matched by age, sex and hospital. Risk factors related to socio-demographic factors, drug use, clinical history, contact patterns and exposures to indoor air pollution were investigated by questionnaire, anthropometric measurements and laboratory assays. Associations were evaluated using a hierarchical logistic regression model.

RESULTS

Pneumonia was associated with human immunodeficiency virus (HIV) infection (Odds Ratio [OR] 2.06, 95% CI 1.44-3.08), anemia (OR 1.91, 1.31-2.74), splenomegaly (OR 2.04, 95% CI 1.14-3.41), recent history of pneumonia (OR 4.65, 95% CI 1.66-12.5), history of pneumonia >2 years previously (OR 17.13, 95% CI 5.01-60.26), coryza in the 2 weeks preceding hospitalization (OR 2.09, 95% CI 1.44-3.03), current smoking (2.19, 95% CI 1.39-3.70), use of khat (OR 3.44, 95% CI 1.72-7.15), use of snuff (OR 2.67, 95% CI 1.35-5.49) and contact with several animal species. Presence of a Bacillus Calmette-Guerin (BCG) scar was associated with protection (OR 0.51, 95% CI 0.32-0.82). The risk factors varied significantly by sex.

CONCLUSION

Pneumonia in Kenyan adults was associated with global risk factors, such as HIV and smoking, but also with specific local factors like drug use and contact with animals. Intervention strategies should account for sex-specific differences in risk factors.

Refining Current Scientific Priorities and Identifying New Scientific Gaps in HIV-Related Heart, Lung, Blood, and Sleep Research

The National Heart, Lung, and Blood Institute (NHLBI) AIDS Program's goal is to provide direction and support for research and training programs in areas of HIV-related heart, lung, blood, and sleep (HLBS) diseases. To better define NHLBI current HIV-related scientific priorities and with the goal of identifying new scientific priorities and gaps in HIV-related HLBS research, a wide group of investigators gathered for a scientific NHLBI HIV Working Group on December 14-15, 2015, in Bethesda, MD. The core objectives of the Working Group included discussions on: (1) HIV-related HLBS comorbidities in the antiretroviral era; (2) HIV cure; (3) HIV prevention; and (4) mechanisms to implement new scientific discoveries in an efficient and timely manner so as to have the most impact on people living with HIV. The 2015 Working Group represented an opportunity for the NHLBI to obtain expert advice on HIV/AIDS scientific priorities and approaches over the next decade.

Effect of Advanced HIV Infection on the Respiratory Microbiome

RATIONALE

Previous work found the lung microbiome in healthy subjects infected with HIV was similar to that in uninfected subjects. We hypothesized the lung microbiome from subjects infected with HIV with more advanced disease would differ from that of an uninfected control population.

OBJECTIVES

To measure the lung microbiome in an HIV-infected population with advanced disease.

METHODS

16s RNA gene sequencing was performed on acellular bronchoalveolar lavage (BAL) fluid from 30 subjects infected with HIV with advanced disease (baseline mean CD4 count, 262 cells/mm(3)) before and up to 3 years after starting highly active antiretroviral therapy (HAART) and compared with 22 uninfected control subjects.

MEASUREMENTS AND MAIN RESULTS

The lung microbiome in subjects infected with HIV with advanced disease demonstrated decreased alpha diversity (richness and diversity) and greater beta diversity compared with uninfected BAL. Differences improved with HAART, but still persisted up to 3 years after starting therapy. Population dispersion in the group infected with HIV was significantly greater than in the uninfected cohort and declined after treatment. There were differences in the relative abundance of some bacteria between the two groups at baseline and after 1 year of therapy. After 1 year on HAART, HIV BAL contained an increased abundance of Prevotella and Veillonella, bacteria previously associated with lung inflammation.

CONCLUSIONS

The lung microbiome in subjects infected with HIV with advanced disease is altered compared with an uninfected population both in diversity and bacterial composition. Differences remain up to 3 years after starting HAART. We speculate an altered lung microbiome in HIV infection may contribute to chronic inflammation and lung complications seen in the HAART era.

Single-institutional experience of clinicopathological analysis and treatment for lung cancer patients with human immunodeficiency virus infection

The advent of antiretroviral therapy has changed the disease spectrum constitution among patients living with human immunodeficiency virus (HIV), while the incidence of death due to non-AIDS-defining cancers, particularly lung cancer, continues to increase in the USA and Europe. However, the availability of detailed reports of the clinical characteristics of lung cancer among Asian populations is limited. The present study retrospectively analyzed the clinical characteristics, treatment regimens and outcomes of lung cancer patients with HIV who were treated in a single institution between 1988 and 2013. Of the 20 lung cancer patients living with HIV included in this study, 90% were diagnosed since 1996 in the post-antiretroviral era. The median CD4+ cell count was 373.5/µl, whereas 65% of the patients were diagnosed with adenocarcinoma and 30% with squamous cell carcinoma. Epidermal growth factor receptor mutations were detected in 3 (27%) of the 11 specimens for which data were available, of which 65% had advanced-stage disease. Of the 20 patients, 9 underwent surgery, 6 received radiotherapy and 5 received chemotherapy as a first-line treatment. Treatment was generally well-tolerated. The median survival period was 35.8 months for all stages and 14.0 months for advanced stages. The treatment outcomes in our institution were favorable in comparison with previous studies from the USA and Europe, although these findings may be due to ethnic differences or the efficacy of treatment for HIV and lung cancer.

Mechanisms Underlying HIV-Associated Noninfectious Lung Disease

Pulmonary disease remains a primary source of morbidity and mortality in persons living with HIV (PLWH), although the advent of potent combination antiretroviral therapy has resulted in a shift from predominantly infectious to noninfectious pulmonary complications. PLWH are at high risk for COPD, pulmonary hypertension, and lung cancer even in the era of combination antiretroviral therapy. The underlying mechanisms of this are incompletely understood, but recent research in both human and animal models suggests that oxidative stress, expression of matrix metalloproteinases, and genetic instability may result in lung damage, which predisposes PLWH to these conditions. Some of the factors that drive these processes include tobacco and other substance use, direct HIV infection and expression of specific HIV proteins, inflammation, and shifts in the microbiome toward pathogenic and opportunistic organisms. Further studies are needed to understand the relative importance of these factors to the development of lung disease in PLWH.

Lung microbiome in human immunodeficiency virus infection

The lung microbiome plays a significant role in normal lung function and disease. Because microbial colonization is likely influenced by immunodeficiency, one would speculate that infection with human immunodeficiency virus (HIV) alters the lung microbiome. Furthermore, how this alteration might impact pulmonary complications now seen in HIV-infected patients on antiretroviral therapy (ART), which has shifted from opportunistic infections to diseases associated with chronic inflammation, is not known. There have been limited publications on the lung microbiome in HIV infection, many of them emanating from the Lung HIV Microbiome Project. Current evidence suggests that the lung microbiome in healthy HIV-infected individuals with preserved CD4 counts is similar to uninfected individuals. However, in individuals with more advanced disease, there is an altered alveolar microbiome characterized by a loss of richness and evenness (alpha diversity) within individuals. Furthermore, as a group the taxa making up the HIV-infected and uninfected lung microbiome are different (differences in beta diversity), and the HIV-infected population is more spread out (greater dispersion) than the uninfected population. These differences decline with ART, but even after effective therapy the alveolar microbiome in HIV-infected individuals contains increased amounts of signature bacteria, some of which have previously been associated with chronic lung inflammation. Furthermore, more recent investigations into the lung virome in HIV infection suggest that perturbations in lung viral communities also exist in HIV infection, and that these too are associated with evidence of lung inflammation. Thus, it is likely both microbiome and virome alterations in HIV infection contribute to lung inflammation in these individuals, which has important implications on the changing spectrum of pulmonary complications in patients living with HIV.

Incidental findings on chest computed tomography are common and linked to inflammation in HIV-infected adults

BACKGROUND

Chest imaging is performed for a variety of reasons in HIV-infected adults. There are limited data on the prevalence of incidental findings, progression of these findings over time and the relationship with inflammation in antiretroviral therapy (ART)-treated HIV-infected adults.

METHODS

This study utilized data from a randomized clinical trial of rosuvastatin in HIV-infected adults on ART. Incidental findings were reported from chest computed tomography (CT) scans obtained for coronary artery calcium score at entry, week 48 and 96. Markers of immune activation and inflammation were measured concurrently. Poisson regression and generalized estimating equations were used.

RESULTS

A total of 147 participants were enrolled. Median age was 46 years, 78% were male, 68% African American and 63% current smokers. At baseline, 57% of participants had at least one incidental lung finding (ILF) and four additional participants had at least one ILF by week 96. At baseline, older age, current smoking, lower nadir CD4⁺ T-cell count and low-density lipoprotein and higher lipoprotein-associated phospholipase A2 (Lp-PLA2) were independently associated with having a greater number of ILFs. In the longitudinal analyses, older age, lower nadir CD4⁺ T-cell count and higher baseline soluble tumour necrosis factor α-receptor I (sTNF-RI) were independently associated with having a greater number of ILFs over 96 weeks.

CONCLUSIONS

Over half of participants had at least one incidental finding on chest CT. Beyond traditional factors of older age and smoking, lower nadir CD4⁺ T-cell count and higher markers of inflammation were associated with having a greater number of ILFs in HIV-infected adults on ART.

Association of COPD With Risk for Pulmonary Infections Requiring Hospitalization in HIV-Infected Veterans

BACKGROUND

Pulmonary infections remain more common in HIV-infected (HIV+) compared with uninfected individuals. The increase in chronic lung diseases among aging HIV+ individuals may contribute to this persistent risk. We sought to determine whether chronic obstructive pulmonary disease (COPD) is an independent risk factor for different pulmonary infections requiring hospitalization among HIV+ patients.

METHODS

We analyzed data from 41,993 HIV+ Veterans in the nationwide Veterans Aging Cohort Study Virtual Cohort from 1996 to 2009. Using International Classification of Diseases, Ninth Revision codes, we identified baseline comorbid conditions, including COPD, and incident community-acquired pneumonia (CAP), pulmonary tuberculosis (TB), and Pneumocystis jirovecii pneumonia (PCP) requiring hospitalization within 2 years after baseline. We used multivariable Poisson regression to determine incidence rate ratios (IRRs) associated with COPD for each type of pulmonary infection, adjusting for comorbidities, CD4 cell count, HIV viral load, smoking status, substance use, vaccinations, and calendar year at baseline.

RESULTS

Unadjusted incidence rates of CAP, TB, and PCP requiring hospitalization were significantly higher among persons with COPD compared to those without COPD (CAP: 53.9 vs. 19.4 per 1000 person-years; TB: 8.7 vs. 2.8; PCP: 15.5 vs. 9.2; P ≤ 0.001). In multivariable Poisson regression models, COPD was independently associated with increased risk of CAP, TB, and PCP (IRR: 1.94, 95% confidence interval [CI]: 1.64 to 2.30; IRR: 2.60, 95% CI: 1.70 to 3.97; and IRR: 1.48, 95% CI: 1.10 to 2.01, respectively).

CONCLUSIONS

COPD is an independent risk factor for CAP, TB, and PCP requiring hospitalization among HIV+ individuals. As the HIV+ population ages, the growing burden of COPD may confer substantial risk for pulmonary infections.

A multi-institutional study of clinicopathological features and molecular epidemiology of epidermal growth factor receptor mutations in lung cancer patients living with human immunodeficiency virus infection

PURPOSE

Lung cancer has become a crucial problem among individuals living with the human immunodeficiency virus (HIV) and causes high mortality in Western countries. Japan has an increasing number of newly infected HIV patients, and lung cancer is becoming a theme in this population. However, clinical factors of this particular population in East Asian are unclear given the identification of ethnic differences in lung cancer in the general population.

METHODS

From 1986 to 2013, a retrospective nationwide study involving Japanese patients living with HIV and diagnosed with lung cancer was undertaken.

RESULTS

Forty-three lung cancer patients with HIV were identified (median age, 60.0 years; males, 97.7%; early-stage cancer, 37.2%; metastatic cancer, 34.9%), 41 (95.3%) of whom developed lung cancer in the antiretroviral era. The median CD4-positive T-cell count was 326 cells/µL. Adenocarcinoma was the most frequent histology (55.8%), followed by squamous cell carcinoma (27.9%). Epidermal growth factor receptor (EGFR) status was examined in 14 patients; five (35.7%) had EGFR mutations. The median overall survival time was 25.1 months for all stages and 7.9 months for advanced-stage cancer. Using univariate analysis, the only favorable prognostic factor for overall survival was cancer stage (p = 0.02).

CONCLUSIONS

The incidence of lung cancer among HIV patients in Japan has been increasing in the past decade. The present Japanese cohort showed similar EGFR mutation status similar to that of general population. The ethnic differences known in the general population were seen even in the population living with HIV, implying distinct clinical characteristics and outcomes from those reported in Western countries.

Chronic obstructive pulmonary disease in patients with HIV: an emerging problem

People with well-controlled HIV now have normal life expectancies and physicians managing these patients are increasingly encountering co-existing chronic obstructive pulmonary disease. This article reviews similarities with this disease in the general population and highlights key differences including significant drug-drug interactions.

Impact of human immunodeficiency virus type-1 sequence diversity on antiretroviral therapy outcomes

Worldwide circulating HIV-1 genomes show extensive variation represented by different subtypes, polymorphisms and drug-resistant strains. Reports on the impact of sequence variation on antiretroviral therapy (ART) outcomes are mixed. In this review, we summarize relevant published data from both resource-rich and resource-limited countries in the last 10 years on the impact of HIV-1 sequence diversity on treatment outcomes. The prevalence of transmission of drug resistant mutations (DRMs) varies considerably, ranging from 0% to 27% worldwide. Factors such as geographic location, access and availability to ART, duration since inception of treatment programs, quality of care, risk-taking behaviors, mode of transmission, and viral subtype all dictate the prevalence in a particular geographical region. Although HIV-1 subtype may not be a good predictor of treatment outcome, review of emerging evidence supports the fact that HIV-1 genome sequence-resulting from natural polymorphisms or drug-associated mutations-matters when it comes to treatment outcomes. Therefore, continued surveillance of drug resistant variants in both treatment-naïve and treatment-experienced populations is needed to reduce the transmission of DRMs and to optimize the efficacy of the current ART armamentarium.

Pulmonary symptoms and diagnoses are associated with HIV in the MACS and WIHS cohorts

Background

Several lung diseases are increasingly recognized as comorbidities with HIV; however, few data exist related to the spectrum of respiratory symptoms, diagnostic testing, and diagnoses in the current HIV era. The objective of the study is to determine the impact of HIV on prevalence and incidence of respiratory disease in the current era of effective antiretroviral treatment.

Methods

A pulmonary-specific questionnaire was administered yearly for three years to participants in the Multicenter AIDS Cohort Study (MACS) and Women’s Interagency HIV Study (WIHS). Adjusted prevalence ratios for respiratory symptoms, testing, or diagnoses and adjusted incidence rate ratios for diagnoses in HIV-infected compared to HIV-uninfected participants were determined. Risk factors for outcomes in HIV-infected individuals were modeled.

Results

Baseline pulmonary questionnaires were completed by 907 HIV-infected and 989 HIV-uninfected participants in the MACS cohort and by 1405 HIV-infected and 571 HIV-uninfected participants in the WIHS cohort. In MACS, dyspnea, cough, wheezing, sleep apnea, and incident chronic obstructive pulmonary disease (COPD) were more common in HIV-infected participants. In WIHS, wheezing and sleep apnea were more common in HIV-infected participants. Smoking (MACS and WIHS) and greater body mass index (WIHS) were associated with more respiratory symptoms and diagnoses. While sputum studies, bronchoscopies, and chest computed tomography scans were more likely to be performed in HIV-infected participants, pulmonary function tests were no more common in HIV-infected individuals. Respiratory symptoms in HIV-infected individuals were associated with history of pneumonia, cardiovascular disease, or use of HAART. A diagnosis of asthma or COPD was associated with previous pneumonia.

Conclusions

In these two cohorts, HIV is an independent risk factor for several respiratory symptoms and pulmonary diseases including COPD and sleep apnea. Despite a higher prevalence of chronic respiratory symptoms, testing for non-infectious respiratory diseases may be underutilized in the HIV-infected population.

High prevalence of malignancy in HIV-positive patients with mediastinal lymphadenopathy: a study in the era of antiretroviral therapy

Background and objective

Mediastinal lymphadenopathy (MLN) in human immunodeficiency virus (HIV) infection has a wide spectrum of aetiologies with different prognoses and treatments. The decision to pursue a histopathological diagnosis represents a clinical challenge as patients present with non-specific symptoms. This study aimed to determine the aetiology and predictive factors of MLN in a cohort of HIV-infected patients in the combination antiretroviral therapy (cART) era.

Methods

Single-centre retrospective cohort study of 217 consecutive HIV-infected patients who underwent computed tomography (CT) of the chest between January 2004 and December 2009. Fifty-two patients were identified to have MLN (>10 mm in short axis). CT images were re-reviewed by an independent radiologist blinded to the clinical information. Final diagnoses of MLN were obtained from clinical records. Multivariate analysis was performed to identify predictors of aetiology of MLN.

Results

Seventeen patients (33%) had a diagnosis of malignancy. Consolidation on CT was associated with a reduced likelihood of malignancy odds ratio (OR) 0.03 (95% confidence interval 0.002–0.422), and larger lymph nodes were associated with an increase in the odds of malignancy (OR 2.89; 95% confidence interval 1.24–6.71). CD4 count was found not to be a predictor of aetiology of MLN.

Conclusions

In the era of combination cART, opportunistic infections and malignancy remain to be the frequent causes of MLN in HIV-positive patients, but the prevalence of non-HIV related malignancy has increased compared with previous studies. Although certain findings are predictors of non-malignant disease, pathological diagnosis of MLN in HIV-positive patients should be pursued whenever possible.

Respiratory infections in HIV-infected adults: epidemiology, clinical features, diagnosis and treatment

PURPOSE OF REVIEW

Using the evidence published over the last 2 years, this review discusses the epidemiology, diagnosis, treatment and prevention of HIV-related pulmonary infections other than mycobacterial disease.

RECENT FINDINGS

Longstanding, vertically acquired and apparently stable HIV infection is associated with significant and symptomatic small airways disease in African adolescents. The use of population-based pneumococcal vaccination in children is changing the severity and serotypes associated with HIV-related pneumococcal disease. Data on the use of blood 1,3,β-D-glucan show it has promise as a rule-out test for Pneumocystis pneumonia (PCP).

SUMMARY

With widespread antiretroviral medication usage, the pattern of HIV-associated pulmonary disease is changing. Whereas opportunistic infections such as PCP still occur in people not using antiretroviral therapy (ART), HIV-related infections are similar to those present in the general population. Chronic lung disease is more prevalent, leading to its own infectious complications. The use of specific immunizations against infections is important, though their precise benefit with concomitant widespread ART and population-based vaccination programmes in the non-HIV community is undetermined.

HIV gp120 induces mucus formation in human bronchial epithelial cells through CXCR4/α7-nicotinic acetylcholine receptors

Lung diseases such as chronic obstructive pulmonary disease (COPD), asthma, and lung infections are major causes of morbidity and mortality among HIV-infected patients even in the era of antiretroviral therapy (ART). Many of these diseases are strongly associated with smoking and smoking is more common among HIV-infected than uninfected people; however, HIV is an independent risk factor for chronic bronchitis, COPD, and asthma. The mechanism by which HIV promotes these diseases is unclear. Excessive airway mucus formation is a characteristic of these diseases and contributes to airway obstruction and lung infections. HIV gp120 plays a critical role in several HIV-related pathologies and we investigated whether HIV gp120 promoted airway mucus formation in normal human bronchial epithelial (NHBE) cells. We found that NHBE cells expressed the HIV-coreceptor CXCR4 but not CCR5 and produced mucus in response to CXCR4-tropic gp120. The gp120-induced mucus formation was blocked by the inhibitors of CXCR4, α7-nicotinic acetylcholine receptor (α7-nAChR), and γ-aminobutyric acid (GABA)AR but not the antagonists of CCR5 and epithelial growth factor receptor (EGFR). These results identify two distinct pathways (α7-nAChR-GABAAR and EGFR) for airway mucus formation and demonstrate for the first time that HIV-gp120 induces and regulates mucus formation in the airway epithelial cells through the CXCR4-α7-nAChR-GABAAR pathway. Interestingly, lung sections from HIV ± ART and simian immunodeficiency virus (SIV) ± ART have significantly more mucus and gp120-immunoreactivity than control lung sections from humans and macaques, respectively. Thus, even after ART, lungs from HIV-infected patients contain significant amounts of gp120 and mucus that may contribute to the higher incidence of obstructive pulmonary diseases in this population.

Human immunodeficiency virus-1 transgene expression increases pulmonary vascular resistance and exacerbates hypoxia-induced pulmonary hypertension development

Pulmonary arterial hypertension (PAH) is a progressive disease characterized by increased pulmonary arterial resistance and vessel remodeling. Patients living with human immunodeficiency virus-1 (HIV-1) have an increased susceptibility to develop severe pulmonary hypertension (PH) irrespective of their CD4+ lymphocyte counts. While the underlying cause of HIV-PAH remains unknown, the interaction of HIV-1 proteins with the vascular endothelium may play a critical role in HIV-PAH development. Hypoxia promotes PH in experimental models and in humans, but the impact of HIV-1 proteins on hypoxia-induced pulmonary vascular dysfunction and PAH has not been examined. Therefore, we hypothesize that the presence of HIV-1 proteins and hypoxia synergistically augment the development of pulmonary vascular dysfunction and PH. We examined the effect of HIV-1 proteins on pulmonary vascular resistance by measuring pressure-volume relationships in isolated lungs from wild-type (WT) and HIV-1 Transgenic (Tg) rats. WT and HIV-1 Tg rats were exposed to 10% O₂ for four weeks to induce experimental pulmonary hypertension to assess whether HIV-1 protein expression would impact the development of hypoxia-induced PH. Our results demonstrate that HIV-1 protein expression significantly increased pulmonary vascular resistance (PVR). HIV-1 Tg mice demonstrated exaggerated pulmonary vascular responses to hypoxia as evidenced by greater increases in right ventricular systolic pressures, right ventricular hypertrophy and vessel muscularization when compared to wild-type controls. This enhanced PH was associated with enhanced expression of HIF-1α and PCNA. In addition, in vitro studies reveal that medium from HIV-infected monocyte derived macrophages (MDM) potentiates hypoxia-induced pulmonary artery endothelial proliferation. These results indicate that the presence of HIV-1 proteins likely impact pulmonary vascular resistance and exacerbate hypoxia-induced PH.

Impact of antiretroviral therapy on lung immunology and inflammation

Human immunodeficiency virus (HIV) infection causes profound changes in the lung compartment characterized by macrophage and lymphocyte activation, secretion of proinflammatory cytokines and chemokines, and accumulation of CD8 T cells in the alveolar space, leading to lymphocytic alveolitis. Because many of the changes seen in the lung can be attributed to the direct effect of HIV on immune cells, therapy to reduce the HIV burden should have significant beneficial effects. Indeed, antiretroviral therapy rapidly reduces the viral burden in the lung, number of CD8 T cells in the alveolar space, and amount of proinflammatory cytokines and chemokines in bronchoalveolar lavage.

Other HIV-associated pneumonias

The incidence, mortality, and epidemiology of human immunodeficiency virus (HIV)-associated pulmonary infections have changed as a result of effective antiretroviral and prophylaxis antimicrobial therapy. The clinical presentation, radiographic abnormalities, and treatment of pneumonia from various uncommon pathogens in patients with AIDS can be different from those in immunocompetent patients. Advances in invasive and noninvasive testing and molecular biological techniques have improved the diagnosis and prognosis of pulmonary infections in patients infected with HIV. This review focuses on pulmonary infections from nontuberculosis mycobacteria, cytomegalovirus, fungi (aspergillosis, cryptococcosis, endemic fungi), and parasites (toxoplasmosis), and uncommon bacterial pneumonia (nocardiosis, rhodococcosis) in these patients.

The impact of HAART on the respiratory complications of HIV infection: longitudinal trends in the MACS and WIHS cohorts

OBJECTIVE

To review the incidence of respiratory conditions and their effect on mortality in HIV-infected and uninfected individuals prior to and during the era of highly active antiretroviral therapy (HAART).

DESIGN

Two large observational cohorts of HIV-infected and HIV-uninfected men (Multicenter AIDS Cohort Study [MACS]) and women (Women's Interagency HIV Study [WIHS]), followed since 1984 and 1994, respectively.

METHODS

Adjusted odds or hazards ratios for incident respiratory infections or non-infectious respiratory diagnoses, respectively, in HIV-infected compared to HIV-uninfected individuals in both the pre-HAART (MACS only) and HAART eras; and adjusted Cox proportional hazard ratios for mortality in HIV-infected persons with lung disease during the HAART era.

RESULTS

Compared to HIV-uninfected participants, HIV-infected individuals had more incident respiratory infections both pre-HAART (MACS, odds ratio [adjusted-OR], 2.4; 95% confidence interval [CI], 2.2-2.7; p<0.001) and after HAART availability (MACS, adjusted-OR, 1.5; 95%CI 1.3-1.7; p<0.001; WIHS adjusted-OR, 2.2; 95%CI 1.8-2.7; p<0.001). Chronic obstructive pulmonary disease was more common in MACS HIV-infected vs. HIV-uninfected participants pre-HAART (hazard ratio [adjusted-HR] 2.9; 95%CI, 1.02-8.4; p = 0.046). After HAART availability, non-infectious lung diseases were not significantly more common in HIV-infected participants in either MACS or WIHS participants. HIV-infected participants in the HAART era with respiratory infections had an increased risk of death compared to those without infections (MACS adjusted-HR, 1.5; 95%CI, 1.3-1.7; p<0.001; WIHS adjusted-HR, 1.9; 95%CI, 1.5-2.4; p<0.001).

CONCLUSION

HIV infection remained a significant risk for infectious respiratory diseases after the introduction of HAART, and infectious respiratory diseases were associated with an increased risk of mortality.

Type 1 interferons suppress accelerated osteoclastogenesis and prevent loss of bone mass during systemic inflammatory responses to Pneumocystis lung infection

HIV infection causes loss of CD4(+) T cells and type 1 interferon (IFN)-producing and IFN-responsive dendritic cells, resulting in immunodeficiencies and susceptibility to opportunistic infections, such as Pneumocystis. Osteoporosis and bone marrow failure are additional unexplained complications in HIV-positive patients and patients with AIDS, respectively. We recently demonstrated that mice that lack lymphocytes and IFN a/b receptor (IFrag(-/-)) develop bone marrow failure after Pneumocystis lung infection, whereas lymphocyte-deficient, IFN α/β receptor-competent mice (RAG(-/-)) had normal hematopoiesis. Interestingly, infected IFrag(-/-) mice also exhibited bone fragility, suggesting loss of bone mass. We quantified bone changes and evaluated the potential connection between progressing bone fragility and bone marrow failure after Pneumocystis lung infection in IFrag(-/-) mice. We found that Pneumocystis infection accelerated osteoclastogenesis as bone marrow failure progressed. This finding was consistent with induction of osteoclastogenic factors, including receptor-activated nuclear factor-κB ligand and the proapoptotic factor tumor necrosis factor-related apoptosis-inducing ligand, in conjunction with their shared decoy receptor osteoprotegerin, in the bone marrow of infected IFrag(-/-) mice. Deregulation of this axis has also been observed in HIV-positive individuals. Biphosphonate treatment of IFrag(-/-) mice prevented bone loss and protected loss of hematopoietic precursor cells that maintained activity in vitro but did not prevent loss of mature neutrophils. Together, these data show that bone loss and bone marrow failure are partially linked, which suggests that the deregulation of the receptor-activated nuclear factor-κB ligand/osteoprotegerin/tumor necrosis factor-related apoptosis-inducing ligand axis may connect the two phenotypes in our model.

Incidence of tuberculosis and early mortality in a large cohort of HIV infected patients receiving antiretroviral therapy in a tertiary hospital in Addis Ababa, Ethiopia

Preceding studies on morbidities and mortalities associated with TB in a cohort of HIV care indicate high incidence of TB development and premature death among patients on highly active antiretroviral treatment (HAART). This study aims to measure the rate of TB, TB mortality, and associated risk factors following commencement of HAART in a cohort of patients attending HIV care in Ethiopia. Patient information was gathered from the hospital register and analysed. TB incidence peaked within six months of HAART initiation, and dropped from 3.3/100 person-years in the first year to 0.4/100 person-years in the fifth year. At baseline, risk factors associated with TB included WHO clinical stage 3 HIV infection (adjusted hazard ratio (AHR) 2.53; 95% CI 1.70-3.70), WHO clinical stage 4 HIV infection (AHR, 3.86; 95% CI 2.54-5.86), and patients who were bed ridden >50% a day (AHR, 1.52; 95% CI 1.13-2.05). The rate of mortality was 6.9% (incidence 2.8 per 100 person-years) and 57% of deaths occurred in the first six months of HAART initiation. Multivariate Cox model indicated WHO clinical stage 4 HIV infection, CD4+ cell count <50 cells/μl, bed ridden >50% a day, and TB after HAART initiation as baseline independent predictors of mortality. Additional evidence shows that regular CD4+monitoring of patients before HAART initiation as well as earlier HAART initiation decreases death, and regular clinical staging decreases TB incidence.

Changes in lung function of HIV-infected patients: a 4.5-year follow-up study

OBJECTIVE

To investigate the development of lung function in HIV-infected patients.

METHODS

In a prospective cohort study, 88 HIV-infected patients had a lung function test performed and 63 patients (72%) had their LFT repeated with a median follow-up period of 4.4 years. Forty-eight per cent were smokers, and at the re-examination, 97% were on combination antiretroviral therapy.

RESULTS

Carbon monoxide diffusion capacity was reduced and decreased over time in both smokers and non-smokers. Alveolar volume decreased and forced vital capacity increased similarly in both smokers and non-smokers. No changes were observed in forced expiratory volume or peak flow, but smokers had reduced values compared with those of the non-smokers at both examinations. FEV1/FVC was reduced especially in smokers and declined in both smokers and non-smokers.

CONCLUSIONS

Carbon monoxide diffusion capacity is reduced in HIV-infected patients and seems to decline over time. Additionally, signs of obstructive lung disease are present in HIV-infected patients and seem to increase over time, although only modestly.

HIV and chronic obstructive pulmonary disease: is it worse and why?

Smoking-related diseases, such as chronic obstructive pulmonary disease (COPD), are of particular concern in the HIV-infected population. Smoking rates are high in this population, and long-term exposure to cigarette smoke in the setting of HIV infection may increase the number of complications seen. Before the era of combination antiretroviral therapy, HIV-infected persons were noted to have an accelerated form of COPD, with significant emphysematous disease seen in individuals less than 40 years old. Unlike many of the AIDS-defining opportunistic infections, HIV-associated COPD may be more common in the current era of HIV because it is frequently reported in patients without a history of AIDS-related pulmonary complications and because many aging HIV-infected individuals have had a longer exposure to smoking and HIV. In this review, we document the epidemiology of HIV-associated COPD before and after the institution of combination antiretroviral therapy, review data suggesting that COPD is accelerated in those with HIV, and discuss possible mechanisms of HIV-associated COPD, including an increased susceptibility to chronic, latent infections; an aberrant inflammatory response; altered oxidant-antioxidant balance; increased apoptosis associated with HIV; and the effects of antiretroviral therapy.

HIV-1 and bacterial pneumonia in the era of antiretroviral therapy

Community-acquired pneumonia affects approximately 4 million people in the United States, with 40,000 deaths per year. The incidence is increased about 35-fold in HIV-infected individuals, and this rate has decreased since the antiretroviral era has begun. Bacterial pneumonia has decreased from 5 to 20 cases per 100 person-years to less than 1 to 5 cases per 100 person-years in the era of antiretroviral therapy. HIV-1 infection impairs the function of neutrophils in the lung and infects CD4⁺ cells and alveolar macrophages. Opportunistic infections dramatically increase local HIV replication in the lung cells, especially alveolar macrophages and CD4⁺ cells. This enhanced replication increases viral mutations and provides opportunities for viral escape from latent reservoirs. Mortality is increased with more comorbidities in this highly susceptible population. Immunization with vaccines is recommended, especially pneumococcal vaccines, although the vaccine itself may stimulate viral replication. Recent studies show that the lower respiratory tract is a microbial reservoir in HIV-infected individuals rather than being a sterile environment, as originally thought. This may provide new opportunities for preventing opportunistic infections in HIV-infected subjects. Bacterial pneumonia presents an ongoing challenge in these high-risk individuals, particularly in studying the functions of the innate and acquired immune response.

HIV-associated lung infections and complications in the era of combination antiretroviral therapy

The spectrum of lung diseases associated with HIV is broad, and many infectious and noninfectious complications of HIV infection have been recognized. The nature and prevalence of lung complications have not been fully characterized since the Pulmonary Complications of HIV Infection Study more than 15 years ago, before antiretroviral therapy (ART) increased life expectancy. Our understanding of the global epidemiology of these diseases in the current ART era is limited, and the mechanisms for the increases in the noninfectious conditions, in particular, are not well understood. The Longitudinal Studies of HIV-Associated Lung Infections and Complications (Lung HIV) Study (ClinicalTrials.gov number NCT00933595) is a collaborative multi-R01 consortium of research projects established by the National Heart, Lung, and Blood Institute to examine a diverse range of infectious and noninfectious pulmonary diseases in HIV-infected persons. This article reviews our current state of knowledge of the impact of HIV on lung health and the development of pulmonary diseases, and highlights ongoing research within the Lung HIV Study.

Clinical characteristics of Japanese lung cancer patients with human immunodeficiency virus infection

BACKGROUND

Lung cancer has emerged as a crucial problem among human immunodeficiency virus (HIV)-infected patients, contributing to significant mortality in Western countries. Japan has an increasing number of newly infected HIV patients, but clinical characteristics of lung cancer have not been well investigated in Asian populations with HIV.

PATIENTS AND METHODS

We retrospectively analyzed patients diagnosed with HIV and lung cancer simultaneously in our institution between 1985 and 2010. Data regarding HIV status, characteristics, treatment, and prognosis of lung cancer were evaluated.

RESULTS

We identified 13 consecutive patients (all men; mean age, 59.0 ± 10.2 years) since 1985, 7 of whom had been diagnosed since 2008. Mean CD4 cell count was 332 ± 159 cells/μL, and HIV viral loads were undetectable in 8 patients (61.5%) at the time of lung cancer diagnosis. The mean latency from HIV diagnosis to detection of lung cancer was 4.0 years. Histological examination demonstrated adenocarcinoma in 9 patients (69.2%), followed by squamous cell carcinoma (23.1%), and small cell carcinoma (7.7%). Among the 7 patients available for examination, 2 patients (28.6%) harbored EGFR mutation. Six patients had stage IA-IIIA, and 7 patients had stage IIIB/IV. Among 6 patients treated with chemotherapy for unresectable stages, 5 (83.3%) achieved a partial response. Median overall survival was 17 months for all stages and 14 months for advanced stages. Toxicities for treatment modalities were largely acceptable.

CONCLUSIONS

Clinical characteristics of Japanese HIV-infected patients with lung cancer resemble those of Western populations. The prognosis for patients in the metastatic stage was better than previously reported.

HIV infection and risk for incident pulmonary diseases in the combination antiretroviral therapy era

RATIONALE

In aging HIV-infected populations comorbid diseases are important determinants of morbidity and mortality. Pulmonary diseases have not been systematically assessed in the combination antiretroviral therapy (ART) era.

OBJECTIVES

To determine the incidence of pulmonary diseases in HIV-infected persons compared with HIV-uninfected persons.

METHODS

We analyzed data from the Veterans Aging Cohort Study Virtual Cohort, consisting of 33,420 HIV-infected veterans and 66,840 age, sex, race and ethnicity, and site-matched HIV-uninfected veterans. Using Poisson regression, incidence rates and adjusted incidence rate ratios were calculated to determine the association of HIV with pulmonary disease. The Virtual Cohort was merged with the 1999 Veterans Large Health Survey to adjust for self-reported smoking in a nested sample (14%).

MEASUREMENTS AND MAIN RESULTS

Incident chronic obstructive pulmonary disease, lung cancer, pulmonary hypertension, and pulmonary fibrosis, as well as pulmonary infections, were significantly more likely among HIV-infected patients compared with uninfected patients in adjusted analyses, although rates of asthma did not differ by HIV status. Bacterial pneumonia and chronic obstructive pulmonary disease were the two most common incident pulmonary diseases, whereas opportunistic pneumonias were less common. Absolute rates of most pulmonary diseases increased with age, although the relative differences between those with and without HIV infection were greatest in younger persons. Chronic obstructive pulmonary disease and asthma, as well as pulmonary infections, were less likely in those with lower HIV RNA levels and use of ART at baseline.

CONCLUSIONS

Pulmonary diseases among HIV-infected patients receiving care within the Veterans Affairs Healthcare System in the combination ART era reflect a substantial burden of non-AIDS-defining and chronic conditions, many of which are associated with aging.

Type-I IFN signaling suppresses an excessive IFN-gamma response and thus prevents lung damage and chronic inflammation during Pneumocystis (PC) clearance in CD4 T cell-competent mice

Immune-reconstitution after highly active antiretroviral therapy (HAART) is often incomplete, and some HIV-infected individuals fail to regenerate type-I interferon (IFN)-producing pDCs. We recently demonstrated that during Pneumocystis (PC) infection in CD4 T cell-competent mice the absence of type-I IFN signaling results in chronic pulmonary inflammation and fibrosis despite clearance. Because the mechanisms involved are poorly understood, we further characterized the role of type-I IFN signaling in immune responses to PC. We show that type-I IFN signaling around day 7 postinfection is critical to the outcome of inflammation. Microarray analysis of pulmonary CD11c(+) cells revealed that at day 7 post infection, wild-type cells up-regulated type-I IFN-responsive genes as well as SOCS1, which is a critical negative-regulator of type-I IFN and IFN-gamma signaling. This was associated with an eosinophilic lung inflammation, PC clearance, and complete restitution. However, pulmonary CD11c(+) cells from IFNAR(-/-) mice demonstrated increased tumor necrosis factor (TNF)-alpha production and lacked SOCS1-induction at day 7. This was followed by a transient lymphocytic and IFN-gamma response before switching to a chronic eosinophilic inflammation of the lung. Early neutralization of TNF-alpha did not prevent chronic inflammation in IFNAR(-/-) mice, but treatment with an anti-IFN-gamma antibody did. We propose that during PC lung infection type-I IFNs induce SOCS1-associated regulatory mechanisms, which prevent excessive IFN-gamma-mediated responses that cause chronic lung damage. Therefore, partial immune-reconstitution in AIDS, attributable to reduced type-I IFN actions, might disrupt regulatory aspects of inflammation, causing unexplained chronic pulmonary complications as seen in some patients during HAART.

[Human immunodeficiency virus and AIDS-associated immune reconstitution syndrome. State of the art]

Since the arrival of highly active antiretroviral therapy (HAART), immune reconstitution syndrome (IRS) has become an increasingly more frequent complication in patients with human immunodeficiency virus (HIV) infection. This article presents a review of the available evidence on this subject, indexed in MEDLINE-PUBMED, BVS-BIREME, and BioMed Central. The review covers the definition, epidemiology, classification, and diagnostic criteria related to IRS. In addition, the clinical particularities of the most frequent etiologies are described, and a proposal for a therapeutic approach is formulated. The prognosis and future implications of this syndrome in the epidemiology of some infectious illnesses in the HIV-positive population are included. Several unresolved aspects are mentioned, such as those related to the pathophysiology of the condition, use of biomarkers for the diagnosis, and the need for evidence-based therapeutic algorithms to enable standardization of treatment for these patients.

Multiple roles for chemokines in the pathogenesis of SIV infection

Chemokines are small chemoattractant cytokines involved in homeostatic and inflammatory immune cell migration. These small proteins have multiple functional properties that extend beyond their most recognized role in controlling cellular migration. The complex immunobiology of chemokines, coupled with the use of subsets of chemokine receptors as HIV-1 and SIV entry co-receptors, suggests that these immunomodulators could play important roles in the pathogenesis associated with infection by HIV-1 or SIV. This review provides an overview of the effects of pathogenic infection on chemokine expression in the SIV/macaque model system, and outlines potential mechanisms by which changes in these expression profiles could contribute to development of disease. Key challenges faced in studying chemokine function in vivo and new opportunities for further study and development of therapeutic interventions are discussed. Continued growth in our understanding of the effects of pathogenic SIV infection on chemokine expression and function and the continuing development of chemokine receptor targeted therapeutics will provide the tools and the systems necessary for future studies of the roles of chemokines in HIV-1 pathogenesis.

Changing global epidemiology of pulmonary manifestations of HIV/AIDS

Tremendous advances have occurred in the care of patients with HIV/AIDS resulting from the advent of highly active antiretroviral therapy (HAART). This has led to differences in the presentations of HIV-related pulmonary disease. Infections such as bacterial pneumonias, particularly Streptococcus pneumoniae, remain commonplace, while opportunistic agents such as Pneumocystis jirovecii remain a concern in patients without adequate access to optimal medical care. The tuberculosis epidemic, once thought to be slowing, has been re-energized by the spread of HIV, particularly in sub-Saharan Africa. Unusual inflammatory responses due to a phenomenon of immune reconstitution, are now recognized as a consequence of HAART, with a reported incidence of IRIS in this setting ranges from 7 to 45% in retrospective reviews. Noninfectious pulmonary conditions such as chronic obstructive lung disease and pulmonary malignancies are gaining prominence as patients are accessing antiretroviral care and enjoying significantly extended survival.