Changing global epidemiology of pulmonary manifestations of HIV/AIDS

COPD in People with HIV: Epidemiology, Pathogenesis, Management, and Prevention Strategies

Chronic obstructive pulmonary disease (COPD) is a progressive respiratory disorder characterized by airflow limitation and persistent respiratory symptoms. People with HIV (PWH) are particularly vulnerable to COPD development; PWH have demonstrated both higher rates of COPD and an earlier and more rapid decline in lung function than their seronegative counterparts, even after accounting for differences in cigarette smoking. Factors contributing to this HIV-associated difference include chronic immune activation and inflammation, accelerated aging, a predilection for pulmonary infections, alterations in the lung microbiome, and the interplay between HIV and inhalational toxins. In this review, we discuss what is known about the epidemiology and pathobiology of COPD among PWH and outline screening, diagnostic, prevention, and treatment strategies.

Granulocyte Macrophage-Colony Stimulating Factor Reverses HIV Protein-Induced Mitochondrial Derangements in Alveolar Macrophages

Despite the advent of antiretroviral therapy, people living with HIV suffer from a range of infectious and noninfectious pulmonary complications. HIV impairs antioxidant defenses and innate immune function of the alveolar macrophage by diminishing granulocyte macrophage-colony stimulating factor (GM-CSF) signaling. Since GM-CSF may be linked to mitochondria, we sought to determine the effects of HIV on GM-CSF receptor expression and alveolar macrophage mitochondrial function. At an academic medical center, studies were completed on alveolar macrophages isolated from both wild-type and HIV transgenic (HIV Tg) rats and human subjects with and without HIV. Primary macrophages were plated and evaluated for expression of GM-CSF receptor beta, phagocytic index, and mitochondrial function in the presence and absence of GM-CSF treatment. GM-CSF receptor expression and mitochondrial function were impaired in macrophages isolated from HIV Tg rats, and treatment with GM-CSF restored GM-CSF receptor expression and mitochondrial function. GM-CSF treatment of HIV Tg rats also increased alveolar macrophage levels of the mitochondrial proteins voltage-dependent anion-selective channel 1 (VDAC) and glucose-regulated protein 75 (Grp75). Similar to the HIV Tg rat model, impairments in mitochondrial bioenergetics were confirmed in alveolar macrophages isolated from human subjects with HIV. HIV-associated impairments in alveolar macrophage mitochondrial bioenergetics likely contribute to innate immune dysfunction in HIV infection, and GM-CSF treatment may offer a novel therapeutic strategy for mitigating these deleterious effects.

Etiology, clinical, and epidemiological characteristics of severe respiratory infection in people living with HIV

People living with HIV (PLWH) are more prone to severe respiratory infections. We used the severe acute respiratory infection (SARI) definition to describe the etiology, clinical, and epidemiological characteristics in this population. This was a prospective observational study including PLWH hospitalized with fever and cough. Those with symptom onset up to 10 days were classified as severe acute respiratory infection and 11–30 days as non-severe acute respiratory infection. Blood, urine samples and nasopharyngeal swabs were collected. Data were extracted from patient charts during their hospital stay. Forty-nine patients were included, median CD4 cell count: 80 cells/mm³, median time since HIV diagnosis and hospital admission: 84 months and 80% were antiretroviral therapy exposed. Twenty-seven patients were classified as SARI. Etiology was identified in 69%, 47% were polymicrobial. Respiratory virus (9 SARI vs. 13 non-SARI), bacteria (5 SARI vs. 4 non-SARI), Mycobacterium tuberculosis (6 SARI group vs. 7 non-SARI group), Pneumocystis jirovecii (4 SARI vs. 1 non-SARI), Cryptococcus neoformans (1 SARI vs. 3 non-SARI), and influenza A (1 SARI vs. 2 non-SARI). Dyspnea was statistically more prevalent in SARI (78% vs. 36%, p = 0.011) but the risk of death was higher in the non-SARI (4% vs. 36%, p = 0.0067). In the severely immunocompromised PLWH, severe acute respiratory infection can be caused by multiple pathogens and codetection is a common feature.

CD4 and Its Relevance to Advanced Glycation End Products in Tuberculosis Patients with Co-morbidity Diabetes

BACKGROUND:

Tuberculosis (TB) is one of the most common infectious diseases found in developing countries. One of the risk factors for TB is diabetes, a chronic metabolic disorder characterised by hyperglycemia. The altered in glucose metabolism will cause dysfunction of phagocyte and antibacterial that furthermore impaired activation of natural killer cells, dendritic cells. These together will alter the balance of T-cell immunity. Under hyperglycemic conditions, AGEs (advanced glycation end products) was increasingly formed and was believed to play a role in cell dysfunctions and diabetic complications. The CD4 deficiency will alter the immunity status in diabetes and TB with co-morbidity diabetes.

AIM:

This aim of this study was to evaluate CD4, and it’s relevant to Advanced Glycation End Products (AGEs) in TB with co-morbidity diabetes.

METHODS:

This is a case-control study with a total of 80 patients (40 diabetes and 40 TB with co-morbidity diabetes were recruited from Murni Teguh memorial Hospital Medan after ethical approval from Health Research Ethical Committee. The CD4, AGEs, Blood glucose and HbA1C were measured.

RESULTS:

There was no statistical difference of CD4, HbA1C and blood glucose within diabetes and TB with co-morbidity diabetes but BMI (p = 0.009) and AGEs (p = 0.001) did. The CD4 below 500 were seen in 15% diabetes and 25% in TB with co-morbidity diabetes but did not show statistical significance difference (p = 0.07). No correlation was found between CD4 and AGEs in TB with co-morbidity diabetes (p = 0.44).

CONCLUSION:

The CD4 was not correlated significantly with AGEs.

Treating HIV-Positive/Non-AIDS Patients for Community-Acquired Pneumonia with ART

PURPOSE OF REVIEW

This article reviews the most recent publications on community-acquired pneumonia (CAP) in the HIV-infected population on antiretroviral therapy (ART), focusing on epidemiology, prognostic factors, etiology, and antimicrobial therapy. The data discussed here were mainly obtained from a non-systematic review using Medline and references from relevant articles.

RECENT FINDINGS

CAP remains a major cause of morbidity and mortality among HIV-infected patients and incurs high health costs despite the introduction of ART. HIV-infected patients are generally known to be more susceptible to bacterial pneumonia. Streptococcus pneumoniae is the most frequently reported pathogen in HIV-infected patients on ART, who present a higher rate of bacteremia than non-HIV-infected patients. Several studies have also examined microbial etiology and prognostic factors of CAP in HIV-infected patients on ART. Despite the high rate of bacterial pneumonia in these patients, mortality rates are not higher than in patients without HIV infection.

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.

Adolescent age is an independent risk factor for abnormal spirometry among people living with HIV in Kenya

OBJECTIVES

As life expectancy of people living with HIV (PLWH) improves in low-income and middle-income countries (LMICs), the spectrum of HIV-related pulmonary complications may reflect a greater burden of chronic lung diseases as in high-income countries. We determined whether the risk of abnormal spirometry was greater among adolescent compared with adult PLWH at the Coptic Hope Center for Infectious Diseases in Nairobi, Kenya, and evaluated the role of other cofactors for abnormal spirometry.

DESIGN

We prospectively enrolled adolescent and adult PLWH for this cross-sectional study.

METHODS

Data collection included standardized questionnaires, clinical assessment, and prebronchodilator and postbronchodilator spirometry. Adolescents additionally underwent noncontrast chest computed tomography. Multivariable logistic regression determined associations of adolescent age with abnormal spirometry, adjusting for cofactors.

RESULTS

Of 427 PLWH, 21 (40%) adolescents and 64 (17%) adults had abnormal spirometry. Among adolescents, 80% had abnormal chest CTs, and 79% had at least one respiratory symptom. Adolescent age (adjusted odds ratio 3.22; 95% confidence interval 1.48-6.98) was independently associated with abnormal spirometry, adjusting for recent CD4, HIV clinical stage, low BMI, indoor kerosene use, smoking pack-years, and prior pulmonary tuberculosis. Additional important cofactors for abnormal spirometry included prior pulmonary tuberculosis (3.15; 1.70-5.58), kerosene use (1.77; 1.04-3.04) and smoking pack-years (1.05; 1.00-1.10). Adolescent age, prior pulmonary tuberculosis, and smoking pack-years were significantly associated with airflow limitation.

CONCLUSION

Adolescent age was independently associated with increased risk of abnormal spirometry, particularly airflow limitation. Studies to improve prevention, detection, and management of chronic lung disease across the lifespan among PLWH are needed in LMICs.

Pulmonary Diseases in Refugees and Migrants in Europe

More than 2 million people fleeing conflict, persecution, and poverty applied for asylum between 2015 and 2016 in the European Union. Due to this, medical practitioners in recipient countries may be facing a broader spectrum of conditions and unusual presentations not previously encountered, including a wide range of infections with pulmonary involvement. Tuberculosis is known to be more common in migrants and has been covered broadly in other publications. The scope of this review was to provide an overview of exotic infections with pulmonary involvement that could be encountered in refugees and migrants and to briefly describe their epidemiology, diagnosis, and management. As refugees and migrants travel from numerous countries and continents, it is important to be aware of the various organisms that might cause disease according to the country of origin. Some of these diseases are very rare and geographically restricted to certain regions, while others have a more cosmopolitan distribution. Also, the spectrum of severity of these infections can vary from very benign to severe and even life-threatening. We will also describe infectious and noninfectious complications that can be associated with HIV infection as some migrants might originate from high HIV prevalence countries in sub-Saharan Africa. As the diagnosis and treatment of these diseases can be challenging in certain situations, patients with suspected infection might require referral to specialized centers with experience in their management. Additionally, a brief description of noncommunicable pulmonary diseases will be provided.

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.

Serum markers as an aid in the diagnosis of pulmonary fungal infections in AIDS patients

Introduction

The etiology of pulmonary infections in HIV patients is determined by several variables including geographic region and availability of antiretroviral therapy.

Materials and methods

A cross-sectional prospective study was conducted from 2012 to 2016 to evaluate the occurrence of pulmonary fungal infection in HIV-patients hospitalized due to pulmonary infections. Patients’ serums were tested for (1–3)-β-D-Glugan, galactomannan, and lactate dehydrogenase. The association among the variables was analyzed by univariate and multivariate regression analysis.

Results

60 patients were included in the study. The patients were classified in three groups: Pneumocystis jirovecii pneumonia (19 patients), community-acquired pneumonia (18 patients), and other infections (23 patients). The overall mortality was 13.3%. The time since diagnosis of HIV infection was shorter in the pneumocystosis group (4.94 years; p = 0.001) than for the other two groups of patients. The multivariate analysis showed that higher (1-3)-β-D-Glucan level (mean: 241 pg/mL) and lactate dehydrogenase (mean: 762 U/L) were associated with the diagnosis of pneumocystosis. Pneumocystosis was the aids-defining illness in 11 out of 16 newly diagnosed HIV-infected patients.

Conclusion

In the era of antiretroviral therapy, PJP was still the most prevalent pulmonary infection and (1-3)-β-D-Glucan and lactate dehydrogenase may be suitable markers to help diagnosing pneumocystosis in our HIV population.

HIV-1 decreases Nrf2/ARE activity and phagocytic function in alveolar macrophages

Respiratory complications occur frequently in individuals living with human immunodeficiency-1 virus (HIV) infection, and there is evidence that HIV-related oxidative stress impairs alveolar macrophage immune function. We hypothesized that nuclear factor (erythroid-derived 2)-like 2 (Nrf2), a master transcription factor that activates the antioxidant response element (ARE) and regulates antioxidant defenses, has an important role in alveolar macrophage (AMs) immune dysfunction in individuals with HIV infections. To test that hypothesis, we analyzed human monocyte-derived macrophages (MDMs) that were either infected with HIV-1 or were exposed to the HIV-related proteins gp120 and Tat ex vivo and determined that either stress affected the expression of Nrf2 and the Nrf2-ARE-dependent genes for NAD(P)H dehydrogenase, quinone 1 (NQO1) and glutamate-cysteine ligase, catalytic subunit (GCLC). We then determined that the expression of Nrf2, NQO1, and GCLC was significantly decreased in primary AMs isolated from HIV-1 transgenic rats. In parallel, treating a rat macrophage cell line (NR8383 cells) with the HIV-related proteins gp120 or Tat similarly decreased the gene and protein expression of Nrf2, NQO1, and GCLC. Further, phagocytic function was decreased in both human MDMs infected with HIV-1 and primary AMs from HIV-1 transgenic rats. Importantly, treating HIV-1-infected human MDMs or AMs from HIV-1 transgenic rats with sulforaphane (SFN, an Nrf2 activator) significantly improved their phagocytic function. The salutary effects of SFN were abrogated by silencing RNA to Nrf2 in wild-type rat macrophages. Our findings demonstrate that HIV-1 infection and exposure to HIV-1-related proteins inhibit Nrf2-ARE activity in the AMs and impair their phagocytic function. Treatments targeted at increasing Nrf2-ARE activity could, therefore, enhance lung innate immunity in people living with HIV-1.

Risk Factors for Hypoxia and Tachypnea Among Adolescents With Vertically-acquired HIV in Nairobi

BACKGROUND

Chronic lung diseases are increasingly recognized complications of vertically-acquired HIV among adolescents in sub-Saharan Africa and may manifest with hypoxia or tachypnea. We sought to determine the prevalence of and risk factors for hypoxia and tachypnea among adolescents with vertically-acquired HIV in Nairobi, Kenya.

METHODS

We performed a cross-sectional analysis of 258 adolescents with vertically-acquired HIV who were initiating care at the Coptic Hope Center for Infectious Diseases. Adolescents with documented pneumonia were excluded. Hypoxia was defined as resting oxygen saturation ≤92%, and tachypnea was based on the 99th percentile of age-appropriate respiratory rates. Logistic regression models adjusted for demographics, and HIV severity estimated odds ratios for risk of hypoxia and tachypnea associated with potential risk factors.

RESULTS

Overall, 11% of adolescents had hypoxia and 55% had tachypnea. Advanced HIV [adjusted odds ratio (aOR): 2.41] and low CD4 (aOR: 1.74) were associated with greater hypoxia risk, but confidence intervals (CIs) were wide and included the null (95% CI: 0.93-6.23 and 0.69-4.39, respectively). Low CD4 (aOR: 2.45, 95% CI: 1.39-4.32), current antiretroviral therapy use (aOR: 0.48, 95% CI: 0.27-0.86) and stunted growth (aOR: 3.46, 95% CI: 1.94-6.18) were associated with altered tachypnea risk.

CONCLUSIONS

Hypoxia and tachypnea are common among adolescents with vertically-acquired HIV. There was a suggestion that advanced HIV and low CD4 were associated with greater hypoxia risk. Low CD4, lack of antiretroviral therapy use and stunted growth are risk factors for tachypnea. Our findings highlight the chronic lung disease burden in this population and may inform diagnostic algorithms.

The Differential Impact of Emphysema on Respiratory Symptoms and 6-Minute Walk Distance in HIV Infection

BACKGROUND

Emphysema is more prevalent in HIV-infected (HIV+) patients independent of smoking behavior. Nonetheless, health effects of emphysema in this population are poorly understood. We determined whether emphysema is associated with a greater burden of pulmonary symptoms and a lower 6-minute walk distance (6MWD) in HIV+ compared with HIV-uninfected (HIV-) subjects.

METHODS

We performed a cross-sectional analysis of 170 HIV+ and 153 HIV- subjects in the Examinations of HIV-Associated Lung Emphysema (EXHALE) cohort study. Subjects completed a self-assessment of respiratory symptoms, pulmonary function testing, and 6MWD testing as well as a chest computed tomography to determine emphysema severity. We used regression models to determine the association of emphysema with respiratory symptoms and 6MWD in HIV+ subjects and compared this to HIV- subjects.

RESULTS

Models stratified by HIV status demonstrated an association between >10% radiographic emphysema and chronic cough and/or phlegm and 6MWD in HIV+ subjects. These associations persisted among the subset without airflow obstruction: those with emphysema had 4.2 (95% confidence interval: 1.3 to 14) times the odds of chronic cough and/or phlegm and walked 60 m (95% confidence interval: 26 to 93) less distance than those without emphysema. There was no association between >10% emphysema and symptoms or 6MWD in HIV- subjects.

CONCLUSIONS

In our cohort, >10% radiographic emphysema was associated with chronic cough and/or phlegm and lower 6MWD in HIV+ but not HIV- subjects. These findings were robust even among HIV+ subjects with milder forms of emphysema and those without airflow obstruction, highlighting the clinical impact of emphysema in these patients.

Widespread activation of immunity and pro-inflammatory programs in peripheral blood leukocytes of HIV-infected patients with impaired lung gas exchange

HIV infection is associated with impaired lung gas transfer as indicated by a low diffusing capacity (DLCO), but the mechanisms are not well understood. We hypothesized that HIV-associated gas exchange impairment is indicative of system-wide perturbations that could be reflected by alterations in peripheral blood leukocyte (PBL) gene expression. Forty HIV-infected (HIV(+)) and uninfected (HIV(-)) men with preserved versus low DLCO were enrolled. All subjects were current smokers and those with acute illness, lung diseases other than COPD or asthma were excluded. Total RNA was extracted from PBLs and hybridized to whole-genome microarrays. Gene set enrichment analysis (GSEA) was performed between HIV(+) versus HIV(-) subjects with preserved DLCO and those with low DLCO to identify differentially activated pathways. Using pathway-based analyses, we found that in subjects with preserved DLCO, HIV infection is associated with activation of processes involved in immunity, cell cycle, and apoptosis. Applying a similar analysis to subjects with low DLCO, we identified a much broader repertoire of pro-inflammatory and immune-related pathways in HIV(+) patients relative to HIV(-) subjects, with up-regulation of multiple interleukin pathways, interferon signaling, and toll-like receptor signaling. We confirmed elevated circulating levels of IL-6 in HIV(+) patients with low DLCO relative to the other groups. Our findings reveal that PBLs of subjects with HIV infection and low DLCO are distinguished by widespread enrichment of immuno-inflammatory programs. Activation of these pathways may alter the biology of circulating leukocytes and play a role in the pathogenesis of HIV-associated gas exchange impairment.

Risk Factors Associated With Quantitative Evidence of Lung Emphysema and Fibrosis in an HIV-Infected Cohort

INTRODUCTION

The disease spectrum for HIV-infected individuals has shifted toward comorbid non-AIDS conditions including chronic lung disease, but quantitative image analysis of lung disease has not been performed.

OBJECTIVES

To quantify the prevalence of structural changes of the lung indicating emphysema or fibrosis on radiographic examination.

METHODS

A cross-sectional analysis of 510 HIV-infected participants in the multicenter Lung-HIV study was performed. Data collected included demographics, biological markers of HIV, pulmonary function testing, and chest computed tomographic examinations. Emphysema and fibrosis-like changes were quantified on computed tomographic images based on threshold approaches.

RESULTS

In our cohort, 69% was on antiretroviral therapy, 13% had a current CD4 cell count less than 200 cells per microliter, 39% had an HIV viral load greater than 500 copies per milliliter, and 25% had at least a trace level of emphysema (defined as >2.5% of voxels <-950HU). Trace emphysema was significantly correlated with age, smoking, and pulmonary function. Neither current CD4 cell count nor HIV viral load was significantly correlated with emphysema. Fibrosis-like changes were detected in 29% of the participants and were significantly correlated with HIV viral load (Pearson correlation coefficient = 0.210; P < 0.05); current CD4 cell count was not associated with fibrosis. In multivariable analyses including age, race, and smoking status, HIV viral load remained significantly correlated with fibrosis-like changes (coefficient = 0.107; P = 0.03).

CONCLUSIONS

A higher HIV viral load was significantly associated with fibrosis-like changes, possibly indicating early interstitial lung disease, but emphysematous changes were not related to current CD4 cell count or HIV viral load.

Incidence of Opportunistic Infections and the Impact of Antiretroviral Therapy Among HIV-Infected Adults in Low- and Middle-Income Countries: A Systematic Review and Meta-analysis

BACKGROUND

To understand regional burdens and inform delivery of health services, we conducted a systematic review and meta-analysis to evaluate the effect of antiretroviral therapy (ART) on incidence of key opportunistic infections (OIs) in human immunodeficiency virus (HIV)-infected adults in low- and middle-income countries (LMICs).

METHODS

Eligible studies describing the cumulative incidence of OIs and proportion on ART from 1990 to November 2013 were identified using multiple databases. Summary incident risks for the ART-naive period, and during and after the first year of ART, were calculated using random-effects meta-analyses. Summary estimates from ART subgroups were compared using meta-regression. The number of OI cases and associated costs averted if ART was initiated at a CD4 count ≥200 cells/µL were estimated using Joint United Nations Programme on HIV/AIDS (UNAIDS) country estimates and global average OI treatment cost per case.

RESULTS

We identified 7965 citations, and included 126 studies describing 491 608 HIV-infected persons. In ART-naive patients, summary risk was highest (>5%) for oral candidiasis, tuberculosis, herpes zoster, and bacterial pneumonia. The reduction in incidence was greatest for all OIs during the first 12 months of ART (range, 57%-91%) except for tuberculosis, and was largest for oral candidiasis, Pneumocystis pneumonia, and toxoplasmosis. Earlier ART was estimated to have averted 857 828 cases in 2013 (95% confidence interval [CI], 828 032-874 853), with cost savings of $46.7 million (95% CI, $43.8-$49.4 million).

CONCLUSIONS

There was a major reduction in risk for most OIs with ART use in LMICs, with the greatest effect seen in the first year of treatment. ART has resulted in substantial cost savings from OIs averted.

HIV and COPD: a conspiracy of risk factors

Chronic obstructive pulmonary disease (COPD) is an under recognized complication of HIV infection. It is estimated that up to 25% of HIV infected people may have COPD. HIV is associated with COPD as a result of a complex interplay of multiple factors such as pulmonary inflammation, recurrent pulmonary infections especially tuberculosis (TB), increased cigarette smoking, socio-economic status, childhood respiratory illnesses and industrial and environmental exposures; each of which are risk factors for COPD in their own right. COPD presents at an earlier age in people with HIV infection. There are over 35 million people living with HIV, and most people infected with HIV live in developing regions of the world where they are faced with multiple risk factors for COPD and suboptimal access to health care. TB is the commonest infectious complication of HIV, and HIV infected persons often experience multiple episodes of TB. Cigarette smoking is increasing in developing countries where the greatest burden of TB and HIV is experienced. Cigarette smoking is associated with increased risk of TB and may be associated with acquisition of HIV infection and progression. It is not clear whether non-infectious pulmonary inflammation persists in the lung when immune reconstitution occurs. Prevention and control of HIV infection must be part of the multiple interventions to reduce the global burden of COPD. A multidisciplinary approach, including behavioural science is required to address this challenge. It presents research opportunities that should be driven by the pulmonology community.

Chest ultrasonography in patients with HIV: a case series and review of the literature

INTRODUCTION

Pulmonary disease is common in HIV-infected patients. Diagnostic means, however, are often scarce in areas where most HIV patients are living. Chest ultrasonography has recently evolved as a highly sensitive and specific imaging tool for diagnosing chest conditions such as pneumothorax, pneumonia and pulmonary edema in critically ill patients. This article addresses the issue of imaging and differentiating common pulmonary conditions in HIV-infected patients by chest ultrasonography.

METHODS

We report chest ultrasound features of five different common pulmonary diseases in HIV-infected patients (bacterial pneumonia, Pneumocystis jirovecii pneumonia, tuberculosis, cytomegalovirus pneumonia and non-Hodgkin lymphoma) and review the respective literature.

CONCLUSIONS

We observed characteristic ultrasound patterns especially in Pneumocystis jirovecii pneumonia and pulmonary lymphoma. Further exploration of chest ultrasonography in HIV-infected patients appears promising and may translate into new diagnostic approaches for pulmonary conditions in patients living with HIV.

Risk factors associated with acute exacerbation of chronic obstructive pulmonary disease in HIV-infected and uninfected patients

OBJECTIVE

To determine the association between HIV infection and other risk factors for acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

DESIGN

Longitudinal, national Veterans Aging Cohort Study including 43 618 HIV-infected and 86 492 uninfected veterans.

METHODS

AECOPD was defined as an inpatient or outpatient COPD ICD-9 diagnosis accompanied by steroid and/or antibiotic prescription within 5 days. We calculated incidence rate ratios (IRR) and 95% confidence intervals (CI) for first AECOPD over 2 years and used Poisson regression models to adjust for risk factors.

RESULTS

Over 234 099 person-years of follow-up, 1428 HIV-infected and 2104 uninfected patients had at least one AECOPD. HIV-infected patients had an increased rate of AECOPD compared with uninfected (18.8 vs. 13.3 per 1000 person-years, P < 0.001). In adjusted models, AECOPD risk was greater in HIV-infected individuals overall (IRR 1.54; 95% CI 1.44-1.65), particularly in those with more severe immune suppression when stratified by CD4 cell count (cells/μl) compared with uninfected (HIV-infected CD4 < 200: IRR 2.30, 95% CI 2.10-2.53, HIV-infected CD4 ≥ 200-349: IRR 1.32, 95% CI 1.15-1.51, HIV-infected CD4 ≥ 350: IRR 0.99, 95% CI 0.88-1.10). HIV infection also modified the association between current smoking and alcohol-related diagnoses with risk for AECOPD such that interaction terms for HIV and current smoking or HIV and alcohol-related diagnoses were each significantly associated with AECOPD.

CONCLUSION

HIV infection, especially with lower CD4 cell count, is an independent risk factor for AECOPD. Enhanced susceptibility to harm from current smoking or unhealthy alcohol use in HIV-infected patients may also contribute to the greater rate of AECOPD.

Association between Highly Active Antiretroviral Therapy and Type of Infectious Respiratory Disease and All-Cause In-Hospital Mortality in Patients with HIV/AIDS: A Case Series

BACKGROUND

Respiratory manifestations of HIV disease differ globally due to differences in current availability of effective highly active antiretroviral therapy (HAART) programs and epidemiology of infectious diseases.

OBJECTIVE

To describe the association between HAART and discharge diagnosis and all-cause in-hospital mortality among hospitalized patients with infectious respiratory disease and HIV/AIDS.

MATERIAL AND METHODS

We retrospectively reviewed the records of patients hospitalized at a specialty hospital for respiratory diseases in Mexico City between January 1st, 2010 and December 31st, 2011. We included patients whose discharge diagnosis included HIV or AIDS and at least one infectious respiratory diagnosis. The information source was the clinical chart. We analyzed the association between HAART for 180 days or more and type of respiratory disease using polytomous logistic regression and all-cause hospital mortality by multiple logistic regressions.

RESULTS

We studied 308 patients, of whom 206 (66.9%) had been diagnosed with HIV infection before admission to the hospital. The CD4+ lymphocyte median count was 68 cells/mm3 [interquartile range (IQR): 30-150]. Seventy-five (24.4%) cases had received HAART for more than 180 days. Pneumocystis jirovecii pneumonia (PJP) (n = 142), tuberculosis (n = 63), and bacterial community-acquired pneumonia (n = 60) were the most frequent discharge diagnoses. Receiving HAART for more than 180 days was associated with a lower probability of PJP [Adjusted odd ratio (aOR): 0.245, 95% Confidence Interval (CI): 0.08-0.8, p = 0.02], adjusted for sociodemographic and clinical covariates. HAART was independently associated with reduced odds (aOR 0.214, 95% CI 0.06-0.75) of all-cause in-hospital mortality, adjusting for HIV diagnosis previous to hospitalization, age, access to social security, low socioeconomic level, CD4 cell count, viral load, and discharge diagnoses.

CONCLUSIONS

HAART for 180 days or more was associated with 79% decrease in all-cause in-hospital mortality and lower frequency of PJP as discharge diagnosis. The prevalence of poorly controlled HIV was high, regardless of whether HIV was diagnosed before or during admission. HIV diagnosis and treatment resources should be improved, and strengthening of HAART program needs to be promoted.

Comparing clinical outcomes in HIV-infected and uninfected older men hospitalized with community-acquired pneumonia

OBJECTIVES

Outcomes of community-acquired pneumonia (CAP) among HIV-infected older adults are unclear.

METHODS

Associations between HIV infection and three CAP outcomes (30-day mortality, readmission within 30 days post-discharge, and hospital length of stay [LOS]) were examined in the Veterans Aging Cohort Study (VACS) of male Veterans, age ≥ 50 years, hospitalized for CAP from 10/1/2002 through 08/31/2010. Associations between the VACS Index and CAP outcomes were assessed in multivariable models.

RESULTS

Among 117 557 Veterans (36 922 HIV-infected and 80 635 uninfected), 1203 met our eligibility criteria. The 30-day mortality rate was 5.3%, the mean LOS was 7.3 days, and 13.2% were readmitted within 30 days of discharge. In unadjusted analyses, there were no significant differences between HIV-infected and uninfected participants regarding the three CAP outcomes (P > 0.2). A higher VACS Index was associated with increased 30-day mortality, readmission, and LOS in both HIV-infected and uninfected groups. Generic organ system components of the VACS Index were associated with adverse CAP outcomes; HIV-specific components were not. Among HIV-infected participants, those not on antiretroviral therapy (ART) had a higher 30-day mortality (HR 2.94 [95% CI 1.51, 5.72]; P = 0.002) and a longer LOS (slope 2.69 days [95% CI 0.65, 4.73]; P = 0.008), after accounting for VACS Index. Readmission was not associated with ART use (OR 1.12 [95% CI 0.62, 2.00] P = 0.714).

CONCLUSION

Among HIV-infected and uninfected older adults hospitalized for CAP, organ system components of the VACS Index were associated with adverse CAP outcomes. Among HIV-infected individuals, ART was associated with decreased 30-day mortality and LOS.

HIV Associated Chronic Obstructive Pulmonary Disease in Nigeria

OBJECTIVE

To determine the prevalence and risk factors for chronic obstructive pulmonary disease (COPD) among HIV-infected adults in Nigeria.

DESIGN

Cross-sectional study.

METHODS

HIV-infected adults aged ≥ 30 years with no acute ailments accessing care at the antiretroviral therapy clinic of Jos University Teaching Hospital were enrolled consecutively. Participants were interviewed to obtain pertinent demographic and clinical information, including exposure to risk factors for COPD. Post-bronchodilator spirometry was carried out. HIV related information was retrieved from the clinic medical records. COPD case-definition was based on the Global Initiative for Obstructive Lung Disease (GOLD) criteria using post-bronchodilator FEV₁/FVC <0.7. COPD prevalence was also calculated using the lower limit of normal for FEV₁/FVC criteria (LLN) from the European Respiratory Society normative equation. Factors associated with COPD were determined using logistic regression models.

RESULTS

Study population comprised 356 HIV infected adults with mean age of 44.5 (standard deviation, 7.1) years and 59% were female. The mean time elapsed since HIV diagnosis was 7.0 (SD, 2.6) years and 97.5% of the respondents were on stable ART with virologic suppression present in 67.2%. Prevalence of COPD were 15.4% (95% confidence interval [CI] 11.7-19.2), 12.07% (95% CI 8.67-15.48), 22.19% (95% CI 18.16-26.83) using GOLD, ERS LLN and GLI LLN diagnostic criteria respectively. In multivariate analyses adjusting for gender, exposure to cigarette smoke or biomass, history of pulmonary tuberculosis, use of antiretroviral therapy, current CD4 T-cell count and HIV RNA, only age > 50 years was independently associated with COPD with OR 3.4; 95% CI 1.42-8.17 when compared to ages 30-40 years.

CONCLUSION

HIV-associated COPD is common in our population of HIV patients.

Lung function abnormalities in HIV-infected adults and children

Despite the advent of antiretroviral therapy (ART), the human immunodeficiency virus (HIV) epidemic remains a global health crisis with a high burden of respiratory disease among infected persons. While the early complications of the epidemic were dominated by opportunistic infections, improved survival has led to the emergence of non-infectious conditions that are associated with chronic respiratory symptoms and pulmonary disability. Obstructive ventilatory defects and reduced diffusing capacity are common findings in adults, and the association between HIV and chronic obstructive pulmonary disease is increasingly recognized. There is synergism between viral factors, opportunistic infections, conventional influences like tobacco smoke and biomass fuel exposure, and potentially, the immunological effects of ART on the development of HIV-associated chronic obstructive lung disease. Pulmonary function data for HIV-infected infants and children are scarce, but shows that bronchiectasis and obliterative bronchiolitis with severe airflow limitation are major problems, particularly in the developing world. However, studies from these regions are sorely lacking. There is thus a major unmet need to understand the influences of chronic HIV infection on the lung in both adults and children, and to devise strategies to manage and prevent these diseases in HIV-infected individuals. It is important for clinicians working with HIV-infected individuals to have an appreciation of their effects on measurements of lung function. This review therefore summarizes the lung function abnormalities described in HIV-positive adults and children, with an emphasis on obstructive lung disease, and examines potential pathogenic links between HIV and the development of chronic pulmonary disability.

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.

Proteomic landscape of bronchoalveolar lavage fluid in human immunodeficiency virus infection

The lung is an important reservoir of human immunodeficiency virus (HIV). Individuals infected with HIV are more prone to pulmonary infections and chronic lung disorders. We hypothesized that comprehensively profiling the proteomic landscape of bronchoalveolar lavage fluid (BALF) in patients with HIV would provide insights into how this virus alters the lung milieu and contributes to pathogenesis of HIV-related lung diseases. BALF was obtained from five HIV-negative (HIV(-)) and six asymptomatic HIV-positive (HIV(+)) subjects not on antiretroviral therapy. Each sample underwent shotgun proteomic analysis based on HPLC-tandem mass spectrometry. Differentially expressed proteins between the groups were identified using statistical methods based on spectral counting. Mechanisms of disease were explored using functional annotation to identify overlapping and distinct pathways enriched between the BALF proteome of HIV(+) and HIV(-) subjects. We identified a total of 318 unique proteins in BALF of HIV(-) and HIV(+) subjects. Of these, 87 were differentially up- or downregulated between the two groups. Many of these differentially expressed proteins are known to interact with key HIV proteins. Functional analysis of differentially regulated proteins implicated downregulation of immune responses in lungs of HIV(+) patients. Combining shotgun proteomic analysis with computational methods demonstrated that the BALF proteome is significantly altered during HIV infection. We found that immunity-related pathways are underrepresented in HIV(+) patients. These findings implicate mechanisms whereby HIV invokes local immunosuppression in the lung and increases the susceptibility of HIV(+) patients to develop a wide range of infectious and noninfectious pulmonary diseases.

Clinical review: Respiratory failure in HIV-infected patients--a changing picture

Respiratory failure in HIV-infected patients is a relatively common presentation to ICU. The debate on ICU treatment of HIV-infected patients goes on despite an overall decline in mortality amongst these patients since the AIDS epidemic. Many intensive care physicians feel that ICU treatment of critically ill HIV patients is likely to be futile. This is mainly due to the unfavourable outcome of HIV patients with Pneumocystis jirovecii pneumonia who need mechanical ventilation. However, the changing spectrum of respiratory illness in HIV-infected patients and improved outcome from critical illness remain under-recognised. Also, the awareness of certain factors that can affect their outcome remains low. As there are important ethical and practical implications for intensive care clinicians while making decisions to provide ICU support to HIV-infected patients, a review of literature was undertaken. It is notable that the respiratory illnesses that are not directly related to underlying HIV disease are now commonly encountered in the highly active antiretroviral therapy (HAART) era. The overall incidence of P. jirovecii as a cause of respiratory failure has declined since the AIDS epidemic and sepsis including bacterial pneumonia has emerged as a frequent cause of hospital and ICU admission amongst HIV patients. The improved overall outcome of HIV patients needing ICU admission is related to advancement in general ICU care, including adoption of improved ventilation strategies. An awareness of respiratory illnesses in HIV-infected patients along with an appropriate diagnostic and treatment strategy may obviate the need for invasive ventilation and improve outcome further. HIV-infected patients presenting with respiratory failure will benefit from early admission to critical care for treatment and support. There is evidence to suggest that continuing or starting HAART in critically ill HIV patients is beneficial and hence should be considered after multidisciplinary discussion. As a very high percentage (up to 40%) of HIV patients are not known to be HIV infected at the time of ICU admission, the clinicians should keep a low threshold for requesting HIV testing for patients with recurrent pneumonia.

HIV-associated bacterial pneumonia

Community-acquired bacterial pneumonia (CAP) remains one of the most common opportunistic infections in patients who are infected with the human immunodeficiency virus (HIV). The risk of CAP increases as the CD4 cell count decreases. The common bacterial pathogens that cause CAP in HIV-infected persons are similar to those in HIV-uninfected individuals, with the pneumococcus being the most common pathogen. Prevention of CAP remains critical and necessitates a comprehensive approach addressing, among many other factors, cigarette smoking cessation strategies, antiretroviral therapy adherence, and immunization against those infections for which effective vaccinations are available.

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.

The impact of asthma and COPD in sub-Saharan Africa

BACKGROUND

Many countries in sub-Saharan Africa have the highest risk of developing chronic diseases and are the least able to cope with them.

AIMS

To assess the current knowledge of the prevalence and impact of asthma and chronic obstructive pulmonary disease (COPD) in sub- Saharan Africa.

METHODS

A literature search was conducted using Medline (1995-2010) and Google Scholar.

RESULTS

Eleven studies of the prevalence of asthma in sub-Saharan Africa were identified, all of which showed a consistent increase, particularly in urban regions. The data on asthma show a wide variation (5.7-20.3%), with the highest prevalence in 'westernised' urban areas. Only two studies of the prevalence of COPD in sub-Saharan Africa have been performed. Nevertheless, COPD has become an increasing health problem in sub-Saharan Africa due to tobacco smoking and exposure to biomass fuels. In most countries of sub-Saharan Africa, 90% of the rural households depend on biomass fuel for cooking and heating, affecting young children (acute lower respiratory infections) and women (COPD). This is the cause of significant mortality and morbidity in the region.

CONCLUSIONS

Asthma and COPD in sub-Saharan Africa are under-recognised, under-diagnosed, under-treated, and insufficiently prevented. A major priority is to increase the awareness of asthma and COPD and their risk factors, particularly the damage caused by biomass fuel. Surveys are needed to provide local healthcare workers with the possibility of controlling asthma and COPD.

Lung Disease in Older Patients with HIV

Successful treatment of HIV with combination antiretroviral therapy (ART) has resulted in an aging HIV-infected population. As HIV-infected patients are living longer, noninfectious pulmonary diseases are becoming increasingly prevalent with a proportional decline in the incidence of opportunistic infections (OIs). Pulmonary OIs such as Pneumocystis jirovecii pneumonia (PCP) and tuberculosis are still responsible for a significant proportion of pulmonary diseases in HIV-infected patients. However, bacterial pneumonia (BP) and noninfectious pulmonary diseases such as chronic obstructive pulmonary disease (COPD), lung cancer, pulmonary arterial hypertension (PAH), and interstitial lung disease (ILD) account for a growing number of pulmonary diseases in aging HIV-infected patients. The purpose of this chapter is to discuss the spectrum and management of pulmonary diseases in aging HIV-infected patients, although limited data exists to guide management of many noninfectious pulmonary diseases in HIV-infected patients. In the absence of such data, treatment of lung diseases in HIV-infected patients should generally follow guidelines for management established in HIV-uninfected patients.

[Anaesthesia for HIV-infected patients]

France is one of main countries affected by the HIV-outbreak in Europe with more than 120,000 cases, among which 34,600 patients having developed an AIDS. The antiretroviral combination therapies (combined antiretroviral therapy [cART]) reduced by half the mortality. A low compliance to cART alters the virologic control and increases the morbimortality. If required, the therapeutic break should be the shortest possible, including the whole treatment (to limit the risk of viral resistance). The perioperative care should take into account the underlying conditions. During the preoperative period, the clinical picture could combine various complications: 1: respiratory impairment; 2: impairment of neuronal functions (related to viral factors, host response and environmental factors such as alcohol, drug addiction, HCV co-infection) inducing a cognitive dysfunction or a peripheral neuropathy; 3: lipodystrophy, dyslipidemia and insulin resistance are the main metabolic cART-related side effects, responsible for atherosclerosis and coronaropathy; 4: major nutritional impairment. Anesthesia for HIV patients is almost the same than usual, without HIV-related contraindication to regional anesthesia. Anesthetic drugs can be associated to cART. The main restriction belongs to the protease inhibitors, which could affect the metabolic pathways of opioids, NSAIDs and benzodiazepines (over dosage risks). During the postoperative period, the follow-up should include the thromboembolism prevention (increased risk compared to main people), the cardiovascular side effects, the nutritional status and the continuation of the treatment. Moreover, the psychological status related and a close collaboration with the corresponding physician is critical.

Interactions between HIV infection and chronic obstructive pulmonary disease: Clinical and epidemiological aspects

Introduction

An association between HIV infection and chronic obstructive pulmonary disease (COPD) has been observed in several studies.

Objective and methods

we conducted a review of the literature linking HIV infection to COPD, focusing on clinical and epidemiological data published before and during widespread highly active antiretroviral therapy (HAART).

Results

Interactions between HIV infection and COPD appear to be influenced by multiple factors. In particular, the bronchopulmonary tract can be damaged by HIV infection, the immunodeficiency it induces, and the resulting increase in the risk of pulmonary infections. In addition, the prevalence of smoking and intravenous drug use is higher in HIV-infected populations, also increasing the risk of COPD. Before the advent of HAART, respiratory tract infections probably played a major role. Since the late 1990s and the widespread use of HAART, the frequency of opportunistic infections has fallen but new complications have emerged as life expectancy has increased.

Conclusion

given the high prevalence of smoking among HIV-infected patients, COPD may contribute significantly to morbidity and mortality in this setting.

A rare case of cor pulmonale secondary to idiopathic pulmonary fibrosis in Nigeria

Idiopathic pulmonary fibrosis (IPF) is a rarely reported disease in Nigeria. Cor pulmonale, one of the complications of this type of diffuse parenchymal lung disease is even rarer. The authors present a Nigerian patient with IPF with a classical high-resolution CT features, managed in our centre together with associated problems.

Impact of macrolide therapy on mortality of HIV-infected patients with community-acquired pneumonia in a tertiary teaching hospital

BACKGROUND

Bacterial pneumonia is one of the main causes of morbidity and mortality in patients infected by the human immunodeficiency virus (HIV). The main objective of this study was to evaluate the effect of macrolide therapy in combination with a beta-lactam based empiric regimen for inpatients with community-acquired pneumonia and HIV.

METHODS

This is a retrospective cohort study of hospitalized patients. Adult patients who had received treatment with ceftriaxone or ceftriaxone plus clarithromycin were included.

RESULTS

76 patients met the inclusion criteria. Among baseline characteristics analyzed, only respiratory rate showed significant difference: patients who had received clarithromycin were more likely to have a respiratory rate > 30/min than patients who received only ceftriaxone (64% versus 36%, p = 0.03). ICU admission was the only outcome that showed a significant difference, more frequent in the ceftriaxone plus clarithromycin group (45% versus 20%, p = 0.03).

CONCLUSIONS

This study does not support the addition of a macrolide to a beta-lactam based regimen in HIV-infected patients. This is probably related to the patients' immunodeficiency status, which impairs the immunomodulatory properties of the macrolides.

Investigation of the significance of Oil Red O-positive macrophage excess in bronchoalveolar lavage fluid during HIV infection

OBJECTIVE

To assess the significance of increased levels of Oil Red O-positive macrophages (ORO-PM) in bronchoalveolar lavage fluids (BALFs) from HIV-positive patients.

METHODS

Cytological data for seventy BALF samples from 66 consecutive HIV-infected patients were analysed according to antiretroviral therapy regimen, presence of Pneumocystis jiroveci infection, blood CD4(+) T cell count, HIV-1 viral load and plasma lipid levels. Non-parametric tests were used to compare the values between groups.

RESULTS

The percentages of ORO-PM were high in this group: 40% [6-80] (median [interquartile range]). They were positively correlated with the BALF total cell count, 21% [5-48.5] for <300 cells/mm(3) and 60% [26.5-80] for >300 cells/mm(3) (P<0.01) but inversely correlated with the percentage of BALF lymphocytes, 50% [20-80] for <15% lymphocytes and 11.5% [2-47] for ≥15% lymphocytes (P<0.01). Antiretroviral therapy with or without protease inhibitors, plasma lipid levels, HIV-1 viral load, blood CD4(+) T cell count or presence of a Pneumocystis jiroveci infection were not correlated with the ORO-PM status.

CONCLUSION

Significantly increased numbers of ORO-PM were correlated with high total cell counts and low lymphocyte counts in BALF, irrespective of disease activity or treatment. Extended work on a larger series of patients needs to be conducted.

Factors associated with excessively lengthy treatment of tuberculosis in the eastern Paris region of France in 2004

Background

Few data are available on prescriber adherence to tuberculosis (TB) treatment guidelines. In particular, excessively long treatment carries a risk of avoidable adverse effects and represents a waste of healthcare resources. We examined factors potentially associated with excessively long treatment.

Methods

We reviewed the medical records of patients diagnosed with TB in 2004 in the eastern Paris region. Sociodemographic and clinical factors associated with excessively long treatment were identified by logistic regression analyses. Based on contemporary guidelines, excessively long treatment was defined as more than 6 months of a four-drug regimen for thoracic TB with full sensitive strains, and more than 12 months for patients with extrathoracic TB.

Results

Analyses concerned 478 patients with a median age of 36.0 ± 13.5 years, of whom 48% were living in precarious conditions (i.e. poor living conditions and/or no health insurance), 80% were born abroad, and 17% were HIV-seropositive. TB was restricted to the chest in 279 patients (isolated pulmonary, pleuropulmonary, and isolated pleural TB in 245, 13, and 21 patients, respectively), exclusively extrathoracic in 115 patients, and mixed in the remaining 84 patients. Treatment was prescribed by a chest specialist in 211 cases (44.1%) and 295 patients (61.7%) were managed in a single institution. The treatment duration complied with contemporary guidelines in 316 cases (66.1%) and was excessively long in 162 cases (33.9%). The median duration of excessively long treatment was 313 days (IQR: 272-412). In multivariate analysis, isolated thoracic TB, previous TB, HIV infection, a prescriber other than a chest specialist, and management in more than one healthcare center during treatment were independently associated with excessively lengthy treatment.

Conclusion

One-third of TB patients received excessively long treatment, reflecting inadequate awareness of management guidelines or unwillingness to implement them.

Diabetic mice display a delayed adaptive immune response to Mycobacterium tuberculosis

Diabetes mellitus (DM) is a major risk factor for tuberculosis (TB) but the defect in protective immunity responsible for this has not been defined. We previously reported that streptozotocin-induced DM impaired TB defense in mice, resulting in higher pulmonary bacterial burden, more extensive inflammation, and higher expression of several proinflammatory cytokines known to play a protective role in TB. In the current study, we tested the hypothesis that DM leads to delayed priming of adaptive immunity in the lung-draining lymph nodes (LNs) following low dose aerosol challenge with virulent Mycobacterium tuberculosis. We show that M. tuberculosis-specific IFN-gamma-producing T cells arise later in the LNs of diabetic mice than controls, with a proportionate delay in recruitment of these cells to the lung and stimulation of IFN-gamma-dependent responses. Dissemination of M. tuberculosis from lung to LNs was also delayed in diabetic mice, although they showed no defect in dendritic cell trafficking from lung to LNs after LPS stimulation. Lung leukocyte aggregates at the initial sites of M. tuberculosis infection developed later in diabetic than in nondiabetic mice, possibly related to reduced levels of leukocyte chemoattractant factors including CCL2 and CCL5 at early time points postinfection. We conclude that TB increased susceptibility in DM results from a delayed innate immune response to the presence of M. tuberculosis-infected alveolar macrophages. This in turn causes late delivery of Ag-bearing APC to the lung draining LNs and delayed priming of the adaptive immune response that is necessary to restrict M. tuberculosis replication.

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.

HIV-1 neuroimmunity in the era of antiretroviral therapy

Human immunodeficiency virus type 1 (HIV-1)-associated neurocognitive disorders (HAND) can affect up to 50% of infected people during the disease course. While antiretroviral therapies have substantively increased the quality of life and reduced HIV-1-associated dementia, less severe minor cognitive and motor deficits continue. Trafficking of HIV-1 into the central nervous system (CNS), peripheral immune activation, dysregulated glial immunity, and diminished homeostatic responses are the disease-linked pathobiologic events. Monocyte-macrophage passage into the CNS remains an underlying force for disease severity. Monocyte phenotypes may change at an early stage of cell maturation and immune activation of hematopoietic stem cells. Activated monocytes are pulled into the brain in response to chemokines made as a result of glial inflammatory processes, which in turn, cause secondary functional deficits in neurons. Current therapeutic approaches are focused on adjunctive and brain-penetrating antiretroviral therapies. These may attenuate virus-associated neuroinflammatory activities thereby decreasing the severity and frequency of HAND.