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

A comprehensive overview on the crosstalk between microRNAs and viral pathogenesis and infection

Infections caused by viruses as the smallest infectious agents, pose a major threat to global public health. Viral infections utilize different host mechanisms to facilitate their own propagation and pathogenesis. MicroRNAs (miRNAs), as small noncoding RNA molecules, play important regulatory roles in different diseases, including viral infections. They can promote or inhibit viral infection and have a pro-viral or antiviral role. Also, viral infections can modulate the expression of host miRNAs. Furthermore, viruses from different families evade the host immune response by producing their own miRNAs called viral miRNAs (v-miRNAs). Understanding the replication cycle of viruses and their relation with host miRNAs and v-miRNAs can help to find new treatments against viral infections. In this review, we aim to outline the structure, genome, and replication cycle of various viruses including hepatitis B, hepatitis C, influenza A virus, coronavirus, human immunodeficiency virus, human papillomavirus, herpes simplex virus, Epstein-Barr virus, Dengue virus, Zika virus, and Ebola virus. We also discuss the role of different host miRNAs and v-miRNAs and their role in the pathogenesis of these viral infections.

HIV infection impairs the host response to Mycobacterium tuberculosis infection by altering surfactant protein D function in the human lung alveolar mucosa

Tuberculosis is the leading cause of death for people living with HIV (PLWH). We hypothesized that altered functions of innate immune components in the human alveolar lining fluid of PLWH (HIV-ALF) drive susceptibility to Mycobacterium tuberculosis (M.tb) infection. Our results indicate a significant increase in oxidation of innate proteins and chemokine levels and significantly lower levels and function of complement components and Th1/Th2/Th17 cytokines in HIV-ALF versus control-ALF (non-HIV-infected people). We further found a deficiency of surfactant protein D (SP-D) and reduced binding of SP-D to M.tb that had been exposed to HIV-ALF. Primary human macrophages infected with M.tb exposed to HIV-ALF were significantly less capable of controlling the infection, which was reversed by SP-D replenishment in HIV-ALF. Thus, based on the limited number of participants in this study, our data suggest that PLWH without antiretroviral therapy (ART) have declining host innate defense function in their lung mucosa, thereby favoring M.tb and potentially other pulmonary infections.

Markers of Inflammation, Tissue Damage, and Fibrosis in Individuals Diagnosed with Human Immunodeficiency Virus and Pneumonia: A Cohort Study

Previous studies have noted that persons living with human immunodeficiency virus (HIV) experience persistent lung dysfunction after an episode of community-acquired pneumonia (CAP), although the underlying mechanisms remain unclear. We hypothesized that inflammation during pneumonia triggers increased tissue damage and accelerated pulmonary fibrosis, resulting in a gradual loss of lung function. We carried out a prospective cohort study of people diagnosed with CAP and/or HIV between 2016 and 2018 in three clinical institutions in Medellín, Colombia. Clinical data, blood samples, and pulmonary function tests (PFTs) were collected at baseline. Forty-one patients were included, divided into two groups: HIV and CAP (n = 17) and HIV alone (n = 24). We compared the concentrations of 17 molecules and PFT values between the groups. Patients with HIV and pneumonia presented elevated levels of cytokines and chemokines (IL-6, IL-8, IL-18, IL-1RA, IL-10, IP-10, MCP-1, and MIP-1β) compared to those with only HIV. A marked pulmonary dysfunction was evidenced by significant reductions in FEF25, FEF25-75, and FEV1. The correlation between these immune mediators and lung function parameters supports the connection between pneumonia-associated inflammation and end organ lung dysfunction. A low CD4 cell count (<200 cells/μL) predicted inflammation and lung dysfunction. These results underscore the need for targeted clinical approaches to mitigate the adverse impacts of CAP on lung function in this population.

Early ART reduces viral seeding and innate immunity in liver and lungs of SIV-infected macaques

Identifying immune cells and anatomical tissues that contribute to the establishment of viral reservoirs is of central importance in HIV-1 cure research. Herein, we used rhesus macaques (RMs) infected with SIVmac251 to analyze viral seeding in the liver and lungs of either untreated or early antiretroviral therapy-treated (ART-treated) RMs. Consistent with viral replication and sensing, transcriptomic analyses showed higher levels of inflammation, pyroptosis, and chemokine genes as well as of interferon-stimulating gene (ISG) transcripts, in the absence of ART. Our results highlighted the infiltration of monocyte-derived macrophages (HLA-DR+CD11b+CD14+CD16+) in inflamed liver and lung tissues associated with the expression of CD183 and CX3CR1 but also with markers of tissue-resident macrophages (CD206+ and LYVE+). Sorting of myeloid cell subsets demonstrated that CD14+CD206-, CD14+CD206+, and CD14-CD206+ cell populations were infected, in the liver and lungs, in SIVmac251-infected RMs. Of importance, early ART drastically reduced viral seeding consistent with the absence of ISG detection but also of genes related to inflammation and tissue damage. Viral DNA was only detected in CD206+HLA-DR+CD11b+ cells in ART-treated RMs. The observation of pulmonary and hepatic viral rebound after ART interruption reinforces the importance of early ART implementation to limit viral seeding and inflammatory reactions.

Long Noncoding RNA Metastasis-Associated Lung Adenocarcinoma Transcript 1 Promotes HIV-1 Replication through Modulating microRNAs in Macrophages

Macrophages can serve as a reservoir for human immunodeficiency-1 (HIV-1) virus in host cells, constituting a barrier to eradication, even in patients who are receiving antiretroviral therapy. Although many noncoding RNAs have been characterized as regulators in HIV-1/AIDS-induced immune response and pathogenesis, only a few long noncoding RNAs (lncRNAs) have demonstrated a close association with HIV-1 replication, and the molecular mechanisms remain unknown. In this study, we investigated how lncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), related microRNAs, and key inflammatory genes alter HIV-1 replication in macrophages. Our data show that HIV-1 infection modulates the expression of miR-155 and miR-150-5p in a time-dependent manner, which is regulated by MALAT1. MALAT1 induced suppressor of cytokine signaling 1 (SOCS1) expression by sponging miR-150-5p in HIV-1-infected macrophages and stimulated inflammatory mediators triggering receptor expressed on myeloid cells/cold inducible RNA binding protein (TREM 1/CIRP) ligand/receptor. The RNA immunoprecipitation (RIP) assay validated the direct interaction within the MALAT1/miR-150-5p/SOCS1 axis. HIV-1 infection-mediated upregulation of MALAT1, SOCS1, and HIV-1 Gag was attenuated by SN50 (an NF-кB p50 inhibitor). MALAT1 antisense oligonucleotides (ASOs) suppressed HIV-1 p24 production and HIV-1 Gag gene expression and decreased expression of miR-155 and SOCS1, as well as the production of proinflammatory cytokines by HIV-1-infected macrophages. In conclusion, HIV-1 infection induces MALAT1, which attenuates miR-150-5p expression and increases SOCS1 expression, promoting HIV-1 replication and reactivation. These data provide new insights into how MALAT1 alters the macrophage microenvironment and subsequently promotes viral replication and suggest a potential role for targeting MALAT1 as a therapeutic approach to eliminate HIV-1 reservoirs. IMPORTANCE Viral reservoirs constitute an obstacle to curing HIV-1 diseases, despite antiretroviral therapy. Macrophages serve as viral reservoirs in HIV infection by promoting long-term replication and latency. Recent studies have shown that lncRNAs can modulate virus-host interactions, but the underlying mechanisms are not fully understood. In this study, we demonstrate how lncRNA MALAT1 contributes to HIV-1 replication through modulation of the miR-150/SOCS1 axis in human macrophages. Our findings have the potential to identify new therapies for eliminating HIV-1 reservoirs in immune cells.

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.

Diagnostic Value of Metagenomic Next-Generation Sequencing for Multi-Pathogenic Pneumonia in HIV-Infected Patients

Background

To evaluate the value and challenges of real-world clinical application of metagenomic next-generation sequencing (mNGS) for bronchoalveolar lavage fluid (BALF) in HIV-infected patients with suspected multi-pathogenic pneumonia.

Methods

Fifty-seven HIV-infected patients with suspected mixed pneumonia who were agreed to undergo the bronchoscopy were recruited and retrospectively reviewed the results of mNGS and conventional microbiological tests (CMTs) of BALF from July 2020 to June 2022.

Results

54 patients were diagnosed with pneumonia including 49 patients with definite pathogens and five patients with probable pathogens. mNGS exhibited a higher diagnostic accuracy for fungal detection than CMTs in HIV-infected patients with suspected pulmonary infection. The sensitivity of mNGS in diagnosis of pneumonia in HIV-infected patients was much higher than that of CMTs (79.6% vs 61.1%; P < 0.05). Patients with mixed infection had lower CD4 T-cell count and higher symptom duration before admitting to the hospital than those with single infection. The detection rate of mNGS for mixed infection was significantly higher than that of CMTs and more co-pathogens could be identified by mNGS. The most common pattern of mixed infection observed was fungi-virus (11/29, 37.9%), followed by fungi-virus-bacteria (6/29, 20.7%) coinfection in HIV-infected patients with multi-pathogenic pneumonia.

Conclusion

mNGS improved the pathogens detection rate and exhibited advantages in identifying multi-pathogenic pneumonia in HIV-infected patients. Early performance of bronchoscopy and mNGS are recommended in HIV-infected patients with low CD4 T cell counts and long duration of symptoms. The most common pattern of mixed infection observed was fungi-virus, followed by fungi-virus-bacteria coinfection in HIV infected patients with multi-pathogenic pneumonia.

Bacteriology of community-acquired pneumonia, antimicrobial susceptibility pattern and associated risk factors among HIV patients, Northeast Ethiopia: cross-sectional study

Objective

Pneumonia is an opportunistic infection and it is a major cause of mortality and morbidity among human immunodeficiency virus/acquired immune deficiency syndrome-positive patients. Previous studies have shown the dominant pathogens bacterial isolates were K. pneumoniae 27.0%, S. aureus 20.8%, S. pneumoniae 18.8% and E. coli 8.3%. This study aimed to determine bacteriology of community-acquired pneumonia, antimicrobial susceptibility pattern and associated risk factors among human immunodeficiency virus patients in the Northeast Ethiopia: cross-sectional study.

Methods

A health facility-based cross-sectional study was conducted from January to April 2021 at six health facilities in Dessie Town. A total of 378 community-acquired pneumonia patients suspected to be human immunodeficiency virus-positive were recruited using a consecutive sampling technique. Sociodemographic and clinical data were collected using a structured questionnaire. A two-milliliter sputum specimen was collected aseptically from each study participant. Samples were cultivated on blood agar, chocolate agar and MacConkey agar to isolate bacterial pathogens. To identify bacteria pathogens Gram stain, colony morphology and biochemical tests were performed. The Kirby-Bauer Disc Diffusion method was used to perform the antimicrobial susceptibility test. Descriptive statistics, logistic regression analysis was carried out using Statistical package for social science version 25 software. p-value < 0.05 with a corresponding 95% confidence interval (CI) was considered for statistical significance.

Result

The overall prevalence of bacterial pneumonia was 175 (46.3%). Gram-negative bacteria accounted for 119 (68%) and the predominant isolates identified were Streptococcus pneumoniae 49 (28%) followed by Klebsiella pneumoniae 46 (26.3%), Pseudomonas aeruginosa 34 (19.4%). There were 148 (84.6%) multidrug-resistant bacteria overall. Statistically significant factors included viral load, cigarette smoking, cluster of differentiation 4 count, alcohol use, World Health Organization clinical stages III and IV and low white blood cell count.

Conclusion

The study found that both multidrug resistance and bacterial pneumonia were high. Thus, bacterial culture and antimicrobial susceptibility tests should be routinely performed in health facilities in order to prevent and control the spread of bacterial infection and concurrent drug resistance.

Systematic assessment of clinical and bacteriological markers for tuberculosis reveals discordance and inaccuracy of symptom-based diagnosis for treatment response monitoring

Background

Clinical symptoms are the benchmark of tuberculosis (TB) diagnosis and monitoring of treatment response but are not clear how they relate to TB bacteriology, particularly the novel tuberculosis-molecular bacterial load assay (TB-MBLA).

Methods

Presumptive cases were bacteriologically confirmed for TB and assessed for symptoms and bacteriological resolution using smear microscopy (SM), culture, and TB-MBLA over 6-month treatment course. Kaplan–Meier and Kappa statistics were used to test the relationship between symptoms and bacteriological positivity.

Results

A cohort of 46 bacteriologically confirmed TB cases were analyzed for treatment response over a 6-month treatment course. Pre-treatment symptoms and bacteriological positivity concurred in over 70% of the cases. This agreement was lost in over 50% of cases whose chest pain, night sweat, and loss of appetite had resolved by week 2 of treatment. Cough resolved at a 3.2% rate weekly and was 0.3% slower than the combined bacteriological (average of MGIT and TB-MBLA positivity) resolution rate, 3.5% per week. A decrease in TB-MBLA positivity reflected a fall in bacillary load, 5.7 ± 1.3- at baseline to 0.30 ± 1.0- log10 eCFU/ml at month 6, and closer to cough resolution than other bacteriological measures, accounting for the only one bacteriologically positive case out of seven still coughing at month 6. Low baseline bacillary load patients were more likely to be bacteriologically negative, HR 5.6, p = 0.003 and HR 3.2, p = 0.014 by months 2 and 6 of treatment, respectively.

Conclusion

The probability of clinical symptoms reflecting bacteriological positivity weakens as the patient progresses on anti-TB therapy, making the symptom-based diagnosis a less reliable marker of treatment response.

A Bayesian approach to simultaneous adjustment of misclassification and missingness in categorical covariates

This study considers concurrent adjustment of misclassification and missingness in categorical covariates in regression models. Under various misclassification and missingness mechanisms, we derive a general mixture regression structure for regression models that can incorporate multiple surrogates of categorical covariates that are subject to misclassification and missingness. In simulation studies, we demonstrate that including observations with missingness and/or multiple surrogates of the covariate helps alleviate the efficiency loss caused by misclassification. In addition, we study the efficacy of misclassification adjustment when the number of categories increases for the covariate of interest. Using data from the Longitudinal Studies of HIV-Associated Lung Infections and Complications, we perform simultaneous adjustment of misclassification and missingness in the self-reported cocaine and heroin use variable when assessing its association with lung density measures.

Dyspnea and Pulmonary Function Among Participants in the Multicenter AIDS Cohort Study Using Protease Inhibitors: A Cross-Sectional Study

People living with HIV (PLWH) have a higher prevalence of respiratory symptoms than people without human immunodeficiency virus (HIV). Antiretroviral therapy has been associated with worsened airflow limitation. This cross-sectional study assessed respiratory health impairment among PLWH and its association with protease inhibitor use using data from Multicenter AIDS Cohort Study visits between April 1, 2017 and March 31, 2018. Participants completed the St. George's Respiratory Questionnaire (SGRQ), modified Medical Research Council (mMRC) dyspnea scale, spirometry, and diffusion capacity measurement. Visit data were compared among PI users, non-PI users, and men without HIV. Binary and ordinal logistic models were used to determine the associations between HIV status, PI use, and covariates with primary outcomes of dichotomized SGRQ and mMRC dyspnea scores. Of PI users, 57/177 (32.2%) self-reported pulmonary disease compared with 132/501 (26.4%) of non-PI users and 105/547 (19.2%) men without HIV. Of PI users, 77/177 (45.3%) had SGRQ scores ≥10, while 171/501 (34.7%) of non-PI users and 162/549 (29.9%) of people living without HIV had SGRQ scores ≥10 (p = .001). Adjusted models found an association between PI use and SGRQ score ≥10 [odds ratio (OR) 1.91 (95% confidence interval [CI] 1.29-2.82), ref: HIV negative and OR 1.50 (95% CI 1.01-2.22) ref: non-PI users]. A similar association was found with mMRC scores and PI use [OR 1.79 (95% CI 1.21-2.64), ref: HIV negative and OR 1.53 (95% CI 1.04-2.25), ref: non-PI users]. PI use is associated with worse respiratory health status, increased dyspnea, and an increased prevalence of self-reported pulmonary disease.

Assessing gender differences among presumed and diagnosed patients with pulmonary TB: observations from Guinea-Bissau

BACKGROUND

Globally, more males than females are diagnosed with pulmonary TB (PTB); however, the cause of this gender disparity remains unknown. We aimed to assess gender differences in an observational cohort of patients with presumed PTB (prePTB) at the Bandim Health Project, Guinea-Bissau.

METHODS

Adult patients with signs and symptoms suggestive of PTB seeking medical care were invited to participate and were referred to comprehensive diagnostic work-up.

RESULTS

We included 2020 patients with prePTB; 54.6% were female. Females were younger than males and more often infected with HIV. More male patients with prePTB were diagnosed with PTB and the proportion of smear-positive cases was greater among males. There was no gender difference in loss to follow-up during the diagnostic process. Of 219 patients with PTB, 205 started treatment, with no difference between genders regarding pretreatment loss to follow-up or treatment outcome.

CONCLUSIONS

More women sought help for symptoms indicative of PTB, yet more men were diagnosed. Women did not have more clinically severe disease at presentation, did not drop out of diagnostic procedures more frequently and did not experience a worse outcome than men. This suggests that the gender gap in PTB is unlikely to be due solely to differences in care-seeking behaviour or diagnostic procedures in our setting.

Incident obstructive lung disease and mortality among people with HIV and a history of injecting drugs

OBJECTIVE

People with HIV (PWH) experience increased prevalence of obstructive lung disease (OLD), regardless of greater observed smoking behaviors. We investigated whether the effect of incident OLD on mortality differed by HIV and HIV viral suppression among persons who inject drugs (PWID) and report smoking history.

DESIGN

ALIVE is a longitudinal, observational cohort study of HIV-positive and seronegative PWID. This analysis included participants who had at least one spirometry measure to assess OLD between 2007 and 2016, excluding those who never smoked (5%, n = 62) or had baseline OLD (17%, n = 269).

METHODS

Incident OLD occurred when the first prebronchodilator forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) less than 0.70 during follow-up. The effect of incident OLD on all-cause mortality was estimated in PWH and seronegative participants using inverse-probability-of-treatment-weighted marginal structural models controlling for baseline (age, race, sex, calendar year, smoking pack-years) and time-varying (smoking intensity, viral suppression, and calendar time) confounders.

RESULTS

Among 1204 participants, 269 (22.3%) and 157 (13.0%) experienced incident OLD and death, respectively, over a median of five person-years of follow-up. There was no effect of OLD on mortality among seronegative participants [hazard ratio = 0.84, 95% confidence interval (CI): 0.47-1.48]; however, PWH diagnosed with OLD experienced an increased mortality risk (hazard ratio = 1.71, 95% CI: 1.04-2.80) during follow-up. HIV viral suppression did not confound or modify the effect of OLD on mortality among PWH.

CONCLUSION

There was an apparent effect of OLD on all-cause mortality irrespective of viral suppression among PWH but not among seronegative persons, after accounting for baseline and time-varying confounders. These results highlight the need for enhanced screening and management of OLD among PWH.

Diagnosis and Management of HIV-Associated Pulmonary Diseases in a Ryan White-Funded Primary Care Setting

Despite widespread use of antiretroviral therapy (ART), people with HIV (PWH) continue to suffer substantial morbidity and mortality from pulmonary diseases. We sought to evaluate the prevalence of pulmonary symptoms, evaluations, and diagnoses (both infectious and noninfectious) among PWH receiving care at one of the largest HIV clinics in the United States. All PWH seen at the Infectious Disease Program in Atlanta, Georgia, from July 2013 to June 2018 were included. Multivariable logistic regression was used to assess the odds of all-cause mortality. Among 8387 patients, median age was 48 years, 35% had documented smoking, 74% were male, and the 47% with ≥1 pulmonary symptom or diagnosis were older and had higher rates of smoking compared to those without any symptoms or diagnoses (p-values <0.0001). Percent on ART was 97% and 81% for individuals with and without symptoms or diagnoses, respectively (p-value <0.0001). Patients with an infectious diagnosis were more likely to have a diagnostic test ordered than those with a noninfectious diagnosis (p-value <0.0001). After adjustment for demographic and clinical risk factors, odds of death were 2.1 times greater [95% confidence interval (CI) = 1.3-3.5] among those with a pulmonary symptom or diagnosis compared to those without. Despite a high prevalence of pulmonary symptoms and diagnoses in this large cohort of PWH, many did not have a complete diagnostic evaluation, particularly those with noninfectious diagnoses. Greater awareness of evaluation and treatment of noninfectious pulmonary diseases among HIV care providers will be critical to improving long-term outcomes for PWH.

Impact of human immunodeficiency virus on pulmonary vascular disease

With the advent of anti-retroviral therapy, non-AIDS-related comorbidities have increased in people living with HIV. Among these comorbidities, pulmonary hypertension (PH) is one of the most common causes of morbidity and mortality. Although chronic HIV-1 infection is independently associated with the development of pulmonary arterial hypertension, PH in people living with HIV may also be the outcome of various co-morbidities commonly observed in these individuals including chronic obstructive pulmonary disease, left heart disease and co-infections. In addition, the association of these co-morbidities and other risk factors, such as illicit drug use, can exacerbate the development of pulmonary vascular disease. This review will focus on these complex interactions contributing to PH development and exacerbation in HIV patients. We also examine the interactions of HIV proteins, including Nef, Tat, and gp120 in the pulmonary vasculature and how these proteins alter the endothelial and smooth muscle function by transforming them into susceptible PH phenotype. The review also discusses the available infectious and non-infectious animal models to study HIV-associated PAH, highlighting the advantages and disadvantages of each model, along with their ability to mimic the clinical manifestations of HIV-PAH.

Case Report: Next-Generation Sequencing in Diagnosis of Pneumonia Due to Pneumocystis jirovecii and Cytomegalovirus in a Patient With HIV Infection

Background: Pulmonary infections remain a significant cause of morbidity and mortality in immunocompromised patients. The pathogens spectrum of pulmonary infection that can affect patients with human immunodeficiency virus (HIV) is wide such as bacterial, fungal, viral, parasitic organisms, and so on. The risk of multi-pathogenic pneumonia is higher in HIV-infected patients. However, the fast and accurate diagnosis of multi-pathogenic pneumonia is challenging because of the limitations of current conventional tests. Case Presentation: Here, we report a case of pneumonia due to Pneumocystis jirovecii and cytomegalovirus (CMV) in a 22-year-old male with newly diagnosed HIV infection. Blood tests revealed a low CD4 count, a chest computed tomography (CT) scan showed extensive ground-glass opacities in the bilateral lung with multiple cavity lesions in the left upper lung. Microscopic examination of stained sputum and bronchoalveolar lavage fluid (BALF) smear specimens did not find any pathogens. There was also no evidence of pathogens known to cause pneumonia in bacteria and fungi culture tests and virus antibodies such as EBV, CMV, and COVID-19. The nucleic acid of CMV in blood was reported by quantitative PCR. Next-generation sequencing (NGS) analysis of BALF specimens identified a large number of P. jirovecii and CMV reads, and confirmed the diagnosis of pneumonia due to P. jirovecii and CMV. Following the patient's treatment with anti-PCP and anti-CMV, the patient was cured and discharged. Conclusions: This case highlights the combined application of NGS in the clinical diagnosis of multi-pathogenic pneumonia in an HIV-infected patient. NGS is proposed as an important adjunctive diagnostic approach for identifying pathogens of multi-pathogenic pneumonia in HIV-infected patients.

T cell-tropic HIV efficiently infects alveolar macrophages through contact with infected CD4+ T cells

Alveolar macrophages (AMs) are critical for defense against airborne pathogens and AM dysfunction is thought to contribute to the increased burden of pulmonary infections observed in individuals living with HIV-1 (HIV). While HIV nucleic acids have been detected in AMs early in infection, circulating HIV during acute and chronic infection is usually CCR5 T cell-tropic (T-tropic) and enters macrophages inefficiently in vitro. The mechanism by which T-tropic viruses infect AMs remains unknown. We collected AMs by bronchoscopy performed in HIV-infected, antiretroviral therapy (ART)-naive and uninfected subjects. We found that viral constructs made with primary HIV envelope sequences isolated from both AMs and plasma were T-tropic and inefficiently infected macrophages. However, these isolates productively infected macrophages when co-cultured with HIV-infected CD4+ T cells. In addition, we provide evidence that T-tropic HIV is transmitted from infected CD4+ T cells to the AM cytosol. We conclude that AM-derived HIV isolates are T-tropic and can enter macrophages through contact with an infected CD4+ T cell, which results in productive infection of AMs. CD4+ T cell-dependent entry of HIV into AMs helps explain the presence of HIV in AMs despite inefficient cell-free infection, and may contribute to AM dysfunction in people living with HIV.

Associations of marijuana with markers of chronic lung disease in people living with HIV

OBJECTIVES

The relationship between marijuana use and markers of chronic lung disease in people living with HIV (PLWH) is poorly understood.

METHODS

We performed a cross-sectional analysis of the Examinations of HIV-Associated Lung Emphysema (EXHALE) study, including 162 HIV-positive patients and 138 participants without HIV. We modelled marijuana exposure as: (i) current daily or weekly marijuana smoking vs. monthly or less often; or (ii) cumulative marijuana smoking (joint-years). Linear and logistic regression estimated associations between marijuana exposure and markers of lung disease, adjusted for tobacco smoking and other factors.

RESULTS

In PLWH, current daily or weekly marijuana use was associated with a larger forced vital capacity (FVC), larger total lung capacity and increased odds of radiographic emphysema compared with marijuana non-smokers in adjusted models; these associations were not statistically significant in participants without HIV. Marijuana joint-years were associated with higher forced expiratory volume in 1 s and FVC in PLWH but not with emphysema.

CONCLUSIONS

In PLWH, marijuana smoking was associated with higher lung volumes and potentially with radiographic emphysema. No consistently negative associations were observed between marijuana and measures of chronic lung health.

Pericytes as novel targets for HIV/SIV infection in the lung

Antiretroviral therapy in HIV patients has lengthened lifespan but led to an increased risk for secondary comorbidities, such as pulmonary complications characterized by vascular dysfunction. In the lung, PDGFRβ+ mesenchymal cells known as pericytes intimately associate with endothelial cells and are key for their survival both structurally and through the secretion of prosurvival factors. We hypothesize that in HIV infection there are functional changes in pericytes that may lead to destabilization of the microvasculature and ultimately to pulmonary abnormalities. Our objective in this study was to determine whether lung pericytes could be directly infected with HIV. We leveraged lung samples from macaque lungs with or without SIV infection and normal human lung for in vitro experiments. Pericytes were isolated based on the marker platelet-derived growth factor receptor-β (PDGFRβ). We determined that lung PDGFRβ-positive (PDGFRβ+) pericytes from both macaques and humans express CD4, the primary receptor for SIV/HIV, as well as the major coreceptors CXCR4 and CCR5. We found cells positive for both PDGFRβ and SIV in lungs from infected macaques. Lung pericytes isolated from these animals also harbored detectable SIV. To confirm relevance to human disease, we demonstrated that human lung pericytes are capable of being productively infected by HIV in vitro, with the time course of infection suggesting development of viral latency. In summary, we show for the first time that SIV/HIV directly infects lung pericytes, implicating these cells as a novel target and potential reservoir for the virus in vivo.

A Rare Case of Multipathogenic Pneumonia in a Patient With Human Immunodeficiency Virus

The incidence of acquired immunodeficiency syndrome (AIDS)-related opportunistic infections has declined dramatically following the introduction of potent antiretroviral therapy (ART). However, pulmonary infections remain a significant cause of morbidity and mortality. The spectrum of pulmonary disease that can affect patients with human immunodeficiency virus (HIV) is wide and includes opportunistic infections with many bacterial, fungal, viral, and parasitic organisms. In this case, we present a 65-year-old woman with HIV, non-compliant with ART, who presented with subacute melena, fatigue, dyspnea, and hemoptysis. After extensive evaluation, she was found to have pneumonia caused by four different pathogens: Strongyloides stercoralis, Pneumocystis jirovecii, Cytomegalovirus (CMV), and Pseudomonas aeruginosa. She received trimethoprim-sulfamethoxazole, steroids, and ivermectin. However, her clinical condition did not improve and she passed away.

Burden of respiratory viral infection in persons with human immunodeficiency virus

This study was conducted to determine the prevalence of respiratory viral infections (RVI) in persons living with HIV (PLH) admitted with a respiratory complaint using real-time reverse transcription polymerase chain reaction and primer-independent next-generation sequencing (NGS). Of 82 subjects, respiratory viruses were the most common pathogen identified in 27 (33%), followed by fungus and bacteria in 8 (10%) and 4 (5%) subjects, respectively. Among subjects with RVI, 11 (41%) required ICU admission and 16 (59%) required mechanical ventilation. The proportion of respiratory viruses identified, and the associated complicated hospital course highlights the significant role that RVIs play in the lung health of PLH.

Endothelial Activation, Innate Immune Activation, and Inflammation Are Associated With Postbronchodilator Airflow Limitation and Obstruction Among Adolescents Living With HIV

BACKGROUND

Chronic inflammation, innate immune activation, T-cell imbalance and endothelial activation have been linked with lung diseases. We sought to determine whether markers of these pathophysiologic pathways were associated with spirometry and chest computed tomography (CT) abnormalities among adolescents living with HIV (ALWH).

SETTING

Coptic Hope Center for Infectious Diseases in Nairobi, Kenya.

METHODS

We performed a cross-sectional study of ALWH (10-19 years old). Participants underwent chest CT, spirometry, and venipuncture for serum biomarkers. We also collected demographic, anthropometric, T-cell subset, antiretroviral therapy, and exposure data. We compared characteristics and biomarkers by airflow obstruction [postbronchodilator FEV1/FVC z-score (zFEV1/FVC) < -1.64]. We used multivariable linear regression to determine associations of log10-transformed biomarkers and chest CT abnormalities with lower postbronchodilator zFEV1/FVC (airflow limitation). We performed exploratory principal components analysis on biomarkers, and determined associations of factors with postbronchodilator zFEV1/FVC and chest CT abnormalities.

RESULTS

Of 47 participants with acceptable quality spirometry, 21 (45%) were female, median age was 13 years and 96% had perinatally-acquired HIV. Median CD4 was 672 cells/µL. Overall, 28% had airflow obstruction and 78% had a chest CT abnormality; airflow obstruction was associated with mosaic attenuation (P = 0.001). Higher endothelial activation (sVCAM-1, sICAM-1), inflammation and innate immune activation (serum amyloid-A, sTREM-1, sCD163), and T-cell imbalance (lower CD4/CD8) markers were associated with airflow limitation. Factors comprising endothelial and innate immune activation were associated with airflow limitation.

CONCLUSIONS

Endothelial activation, innate immune activation, T-cell imbalance, and chronic inflammation are associated with airflow limitation and obstruction, providing insights into chronic lung disease pathophysiology among ALWH.

HIV-1 Transcription Inhibitor 1E7-03 Restores LPS-Induced Alteration of Lung Leukocytes' Infiltration Dynamics and Resolves Inflammation in HIV Transgenic Mice

Human immunodeficiency virus (HIV)-infected individuals treated with anti-retroviral therapy often develop chronic non-infectious lung disease. To determine the mechanism of HIV-1-associated lung disease we evaluated the dynamics of lung leukocytes in HIV-1 transgenic (Tg) mice with integrated HIV-1 provirus. In HIV-Tg mice, lipopolysacharide (LPS) induced significantly higher levels of neutrophil infiltration in the lungs compared to wild-type (WT) mice. In WT mice, the initial neutrophil infiltration was followed by macrophage infiltration and fast resolution of leukocytes infiltration. In HIV-Tg mice, resolution of lung infiltration by both neutrophils and macrophages was significantly delayed, with macrophages accumulating in the lumen of lung capillaries resulting in a 45% higher rate of mortality. Trans-endothelial migration of HIV-Tg macrophages was significantly reduced in vitro and this reduction correlated with lower HIV-1 gene expression. HIV-1 transcription inhibitor, 1E7-03, enhanced trans-endothelial migration of HIV-Tg macrophages in vitro, decreased lung neutrophil infiltration in vivo, and increased lung macrophage levels in HIV-Tg mice. Moreover, 1E7-03 reduced levels of inflammatory IL-6 cytokine, improved bleeding score and decreased lung injury. Together this indicates that inhibitors of HIV-1 transcription can correct abnormal dynamics of leukocyte infiltration in HIV-Tg, pointing to the utility of transcription inhibition in the treatment of HIV-1 associated chronic lung disease.

Diagnostic accuracy of magnetic resonance imaging in the evaluation of pulmonary infections in immunocompromised patients

Purpose

To evaluate the accuracy of magnetic resonance imaging (MRI) for diagnosing pulmonary infections in immunocompromised adults.

Material and methods

Computed tomography (CT) and MRI chest were performed in 35 immuno-compromised patients suspected of pulmonary infection. The MRI sequences that were performed included axial and coronal T2 half-Fourier acquisition single-shot turbo spin-echo (HASTE), spectrally attenuated inversion recovery (SPAIR), true fast imaging with steady-state free precession (TRUFI), and three-dimensional fast low angle shot (3D FLASH) using breath-hold and respiratory triggered BLADE (proprietary name for periodically rotated overlapping parallel lines with enhanced reconstruction). The presence of nodules, consolidations, and ground-glass opacities was evaluated. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for MRI using CT scan as a reference standard.

Results

The sensitivity of MRI in nodule detection was 50% overall and 75% for nodules measuring more than 5 mm. Consolidation was detected with 100% sensitivity. Sensitivity and PPV for the detection of ground-glass opacities (GGOs) were 77.7% and 53.8%, respectively. T2 HASTE axial had the fewest image artefacts. Respiratory triggered MR pulse sequence did not add any significant diagnostic information as compared to the non-respiratory triggered MR pulse sequences.

Conclusions

Sensitivity for detecting small nodules and GGOs on MR is poor; CT scan remains the imaging modality of choice for the evaluation of pulmonary infections in immunocompromised patients. However, MRI can be used in the follow-up imaging of these patients.

Inflammatory mediators and lung abnormalities in HIV: A systematic review

HIV and pneumonia infections have both been shown to negatively impact lung function. However, evidence of the role of inflammation on lung dysfunction in HIV and pneumonia co-infected individuals remains limited. We aimed to systematically review the association of inflammatory markers and lung abnormalities in HIV and pneumonia co-infected individuals. This systematic review was registered with the International Prospective Register of Systematic Reviews on August 15, 2017 (registration number CRD42017069254) and used 4 databases (Cochrane Central Register of Controlled Trials, PubMed Central, Clinical Trials.gov and Google Scholar). All clinical trial, observational, and comparative studies targeting adult (> 18 years old) populations with HIV, pneumonia, or both, that report on immune response (cytokine, chemokine, or biomarker), and lung abnormality as an outcome were eligible. Data selection, risk of bias and extraction were performed independently by 2 blinded reviewers. Due to heterogeneity among the articles, a qualitative synthesis was performed. Our search strategy identified 4454 articles of which, 7 met our inclusion criteria. All of the studies investigated the ability of circulating biomarkers to predict lung damage in HIV. None of the articles included patients with both HIV and pneumonia, nor pneumonia alone. Markers of inflammation (IL-6, TNF-α, CRP), innate defense (cathelicidin), monocyte and macrophage activation (sCD14, sCD163 and, IL-2sRα), endothelial dysfunction (ET-1) and general immune health (CD4/CD8 ratio) were associated with lung abnormalities in HIV. This review highlights the lack of available information regarding the impact of inflammatory mediators on lung function in HIV and pneumonia populations, therefore opportunities to prevent lung damage with available anti-inflammatory treatment or to investigate new ones still remain.

Infusion of HIV-1 Nef-expressing astrocytes into the rat hippocampus induces enteropathy and interstitial pneumonitis and increases blood-brain-barrier permeability

Even though HIV-1 replication can be suppressed by combination antiretroviral therapy (cART) inflammatory processes still occur, contributing to comorbidities. Comorbidities are attributed to variety of factors, including HIV-1 mediated inflammation. Several HIV-1 proteins mediate central nervous system (CNS) inflammation, including Nef. Nef is an early HIV-1 protein, toxic to neurons and glia and is sufficient to cause learning impairment similar to some deficits observed in HIV-1 associated neurocognitive disorders. To determine whether hippocampal Nef expression by astrocytes contributes to comorbidities, specifically peripheral inflammation, we infused Sprague Dawley rats with GFP- (control) or Nef-transfected astrocytes into the right hippocampus. Brain, lung, and ileum were collected postmortem for the measurement of inflammatory markers. Increased blood-brain-barrier permeability and serum IL-1β levels were detected in the Nef-treated rats. The lungs of Nef-treated rats demonstrated leukocyte infiltration, macrophage upregulation, and enhanced vascular permeability. Ileal tissue showed reactive follicular lymphoid hyperplasia, increased permeability and macrophage infiltration. The intracerebroventricular application of IL-1 receptor antagonist reduced infiltration of immune cells into ileum and lung, indicating the important role of IL-1β in mediating the spread of inflammation from the brain to other tissues. This suggests that localized expression of a single viral protein, HIV-1 Nef, can contribute to a broader inflammatory response by upregulation of IL-1β. Further, these results suggest that Nef contributes to the chronic inflammation seen in HIV patients, even in those whose viremia is controlled by cART.

History of tuberculosis is associated with lower exhaled nitric oxide levels in HIV-infected children

Objective:

HIV disrupts host defense mechanisms and maintains chronic inflammation in the lung. Nitric oxide is a marker of lung inflammation and can be measured in the exhaled air. We investigated the relationship between exhaled nitric oxide (eNO), HIV status and airway abnormalities in perinatally HIV-infected children aged 6–19 years.

Design:

A cross-sectional study.

Methods:

HIV-infected individuals on antiretroviral therapy and HIV-uninfected children with no active tuberculosis (TB) or acute respiratory tract infection were recruited from a public hospital in Harare, Zimbabwe. Clinical history was collected and eNO testing and spirometry was performed. The association between eNO and explanatory variables (HIV, FEV1 z-score, CD4⁺ cell count, viral load, history of TB) was investigated using linear regression analysis adjusted for age, sex and time of eNO testing.

Results:

In total, 222 HIV-infected and 97 HIV-uninfected participants were included. Among HIV-infected participants, 57 (25.7%) had a history of past TB; 56 (25.2%) had airway obstruction, but no prior TB. HIV status was associated with lower eNO level [mean ratio 0.79 (95% confidence interval, 95% CI 0.65–0.97), P = 0.03]. Within the HIV-infected group, history of past TB was associated with lower eNO levels after controlling for age, sex and time of eNO testing [0.79 (95% CI 0.67–0.94), P = 0.007].

Conclusion:

HIV infection and history of TB were associated with lower eNO levels. eNO levels may be a marker of HIV and TB-induced alteration in pulmonary physiology; further studies focused on potential causes for lower eNO levels in HIV and TB are warranted.

Macrophages exposed to HIV viral protein disrupt lung epithelial cell integrity and mitochondrial bioenergetics via exosomal microRNA shuttling

Antiretroviral therapy extends survival but does not eliminate HIV from its cellular reservoirs. Between immune and stromal cells in the tissue microenvironment, a dynamic intercellular communication might influence host viral immune responses via intercellular transfer of extracellular vehicles (EVs) (microvesicles, exosome, or apoptotic bodies). It is increasingly recognized that HIV-infected macrophage-secreted nucleotide-rich exosomes might play a critical role in mediating communication between macrophages and other structural cells; however, molecular mechanisms underlying cell–cell crosstalk remain unknown. Here we show that HIV-1-infected macrophages and HIV-1 proteins Tat or gp120-treated macrophages express high levels of microRNAs, including miR-23a and miR-27a. Identical miRNAs expression patterns were detected in macrophage-secreted exosomes isolated from bronchoalveolar lavage fluid of HIV transgenic rats. Tat-treated macrophage-derived exosomal miR-23a attenuated posttranscriptional modulation of key tight junction protein zonula occludens (ZO-1) 3′-UTR in epithelial cells. In parallel, exosomal miR-27a released from Tat-treated macrophages altered the mitochondrial bioenergetics of recipient lung epithelial cells by targeting peroxisome proliferator-activated receptor gamma (PPARγ), while simultaneously stimulating glycolysis. Together, exosomal miRNAs shuttle from macrophages to epithelial cells and thereby explain in part HIV-mediated lung epithelial barrier dysfunction. These studies suggest that targeting miRNAs may be of therapeutic value to enhance lung health in HIV.

Treating bacterial pneumonia in people living with HIV

Introduction: Bacterial pneumonia remains an important cause of morbidity and mortality in people living with HIV (PLWH) in the antiretroviral therapy (ART) era. In addition to being immunocompromised, as reflected by low CD4 cell counts and elevated HIV viral loads, PLWH often have other behaviors associated with an increased risk of pneumonia including smoking and injected drug use. As PLWH are aging, comorbid conditions such as chronic obstructive pulmonary disease (COPD), cancers, and cardiovascular, renal and liver diseases are emerging as additional risk factors for pneumonia. Pathogens are often similar to those in HIV-uninfected individuals; however, PLWH are at risk for unusual and/or multi-drug resistant organisms causing bacterial pneumonia based, in part, on their CD4 cell counts and other exposures. Areas covered: In this review, we focus on the recognition and management of bacterial community-acquired pneumonia (CAP) in PLWH. Along with antimicrobial treatment, we discuss prevention strategies such as vaccination and smoking cessation. Expert opinion: Early initiation of ART after HIV infection can decrease the risk of pneumonia. Improved efforts at vaccination, smoking cessation, and reduction of other substance use are urgently needed in PLWH to decrease the risk for bacterial pneumonia. As PLWH are aging, comorbidities are additional risk factors for bacterial CAP.

Case fatality rate and viral aetiologies of acute respiratory tract infections in HIV positive and negative people in Africa: The VARIAFRICA-HIV systematic review and meta-analysis

•

This first meta-analysis compare CFR between HIV(+) and HIV(-) with ARTI in Africa

•

We found higher rate of mortality in HIV(+) people compared to HIV(-)

•

In subgroup analysis, the CFR was higher in HIV + children <5 compared to people >5

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Viral aetiologies of ARTI were not different between HIV(+) and HIV(-)

Background

To set priorities for efficient control of acute respiratory tract infection (ARTI) in Africa, it is necessary to have accurate estimate of its burden, especially among HIV-infected populations.

Objectives

To compare case fatality rate (CFR) and viral aetiologies of ARTI between HIV-positive and HIV-negative populations in Africa.

Study design

We searched PubMed, EMBASE, Web of Knowledge, Africa Journal Online, and Global Index Medicus to identify studies published from January 2000 to April 2018. Random-effect meta-analysis method was used to assess association (pooled weighted odds ratios (OR) with 95% confidence interval (CI)).

Results

A total of 36 studies (126,526 participants) were included. CFR was significantly higher in patients with HIV than in HIV-negative controls (OR 4.10, 95%CI: 2.63–6.27, I²: 93.7%). The risk was significantly higher among children ≤5 years (OR 5.51, 95%CI 2.83–10.74) compared to people aged >5 years (OR 1.48, 95%CI 1.17–1.89); p = 0.0002. There was no difference between children (15 years) and adults and between regions of Africa. There was no difference for viral respiratory aetiologies (Enterovirus, Adenovirus, Bocavirus, Coronavirus, Metapneumovirus, Parainfluenza, Influenza, and Respiratory Syncytial Virus) of ARTI between HIV-positive and HIV-negative people, except for Rhinovirus where being HIV-negative was associated with Rhinovirus (OR 0.70; 95%CI 0.51–0.97, I²: 63.4%).

Conclusions

This study shows an increased risk of deaths among HIV-infected individuals with ARTI, however with no difference in viral aetiologies compared to HIV-negative individuals in Africa. ARTI deserves more attention from HIV health-care providers for efficient control. Specific strategies are needed for HIV-positive children under 5.

MiR-144 mediates Nrf2 inhibition and alveolar epithelial dysfunction in HIV-1 transgenic rats

Chronic HIV infection causes redox stress and increases the risk of acute and chronic lung injury, even when individuals are adherent to antiretroviral therapy. HIV-1 transgene expression in rats inhibits nuclear factor (erythroid-derived 2)-like 2 (Nrf2), which regulates antioxidant defenses and alveolar epithelial cell (AEC) barrier function, but the mechanism is unknown. In this study, we present novel evidence that these pathological effects of HIV are mediated by microRNA-144 (miR-144). HIV-1 transgene expression in vivo increases the expression of miR-144 in the alveolar epithelium, and this can be replicated by direct exposure of naïve primary AECs to either Tat or gp120 ex vivo. Further, treating naïve primary AECs with a miR-144 mimic decreased the expression and activity of Nrf2 and inhibited their barrier formation. In contrast, treatment with a miR-144 antagomir increased the expression and activity of Nrf2 and improved barrier function in primary AECs isolated from HIV-1 transgenic rats. Importantly, either delivering the miR-144 antagomir intratracheally, or directly activating Nrf2 by dietary treatment with PB123, increased Nrf2 expression and barrier formation in HIV-1 transgenic rat AECs. This study provides new experimental evidence that HIV-induced inhibition of Nrf2 and consequent AEC barrier dysfunction are mediated via miR-144, and that these pathophysiological effects can be mitigated in vivo by either directly antagonizing miR-144 or activating Nrf2. Our findings suggest that targeting the inhibition of Nrf2 in individuals living with HIV could enhance their lung health and decrease the lung-specific morbidity and mortality that persists despite antiretroviral therapy.

HIV infection is an independent risk factor for decreased 6-minute walk test distance

Background

Ambulatory function predicts morbidity and mortality and may be influenced by cardiopulmonary dysfunction. Persons living with HIV (PLWH) suffer from a high prevalence of cardiac and pulmonary comorbidities that may contribute to higher risk of ambulatory dysfunction as measured by 6-minute walk test distance (6-MWD). We investigated the effect of HIV on 6-MWD.

Methods

PLWH and HIV-uninfected individuals were enrolled from 2 clinical centers and completed a 6-MWD, spirometry, diffusing capacity for carbon monoxide (DL_CO) and St. George’s Respiratory Questionnaire (SGRQ). Results of 6-MWD were compared between PLWH and uninfected individuals after adjusting for confounders. Multivariable linear regression analysis was used to determine predictors of 6-MWD.

Results

Mean 6-MWD in PLWH was 431 meters versus 462 in 130 HIV-uninfected individuals (p = 0.0001). Older age, lower forced expiratory volume (FEV₁)% or lower forced vital capacity (FVC)%, and smoking were significant predictors of decreased 6-MWD in PLWH, but not HIV-uninfected individuals. Lower DL_CO% and higher SGRQ were associated with lower 6-MWD in both groups. In a combined model, HIV status remained an independent predictor of decreased 6-MWD (Mean difference = -19.9 meters, p = 0.005).

Conclusions

HIV infection was associated with decreased ambulatory function. Airflow limitation and impaired diffusion capacity can partially explain this effect. Subjective assessments of respiratory symptoms may identify individuals at risk for impaired physical function who may benefit from early intervention.

Etiology of Respiratory Complications among Iranian HIV Infected Patients

BACKGROUND

Infection with Human Immune deficiency Virus (HIV) is a growing problem in developing countries. Among HIV infected cases, respiratory complications are common, dissimilar in different setting and their diagnosis is challenging. The aim of this study was to determine the spectrum of infectious and non-infectious pulmonary complications among HIV infected patients.

MATERIALS AND METHODS

The retrospective study was done among 710 HIV infected patients admitted in Masih Daneshvari Hospital, National Research Institute of Tuberculosis and Lung Diseases, Tehran, Iran from January 2003 to March 2017. Demographic, clinical, radiologic and laboratory data of 836 episodes of pulmonary complications were reviewed and final diagnosis were extracted.

RESULTS

Mean of CD₄ cell count was 90±131 ×10⁶ cells/L. Definite etiology was found for 653 episodes (78.1%) of pulmonary complications. Infectious respiratory diseases were clearly more common than non-infectious etiologies, 86.1 and 7.6%, respectively. Pulmonary tuberculosis, as the leading cause, involved 542 cases (64.8%) and Pneumocystis jiroveci (P. jiroveci) was the second infectious agent that was found in 111 cases (13.2%). Among non- infectious causes, bronchiectasis and Chronic Obstructive Pulmonary Disease (COPD) exacerbation were on the top of the list, 21 of 64 (32.8%) and 18 0f 64 (28.1%), respectively. Many patients had more than one etiology. P. jiroveci had the highest tendency for dual infections (43 episodes).

CONCLUSION

Pulmonary complications, especially infections are common among HIV cases in Iran, among them tuberculosis is the most common. Respiratory problems may be the first presentation of HIV infection. Clinicians should be aware about the risk of dual infections. Screening for HIV among all tuberculosis cases and vice versa is recommend.

Pediatric Human Immunodeficiency Virus and Otolaryngologic Manifestations: An Analysis of Hospital Admissions From 1997 to 2012

OBJECTIVES/HYPOTHESIS

Many human immunodeficiency virus (HIV)-infected pediatric patients develop otolaryngologic disease. We aimed to characterize their otolaryngologic manifestations by type and demographic variation, and model temporal trends.

STUDY DESIGN

Retrospective cohort review.

METHODS

A retrospective review utilizing the Kids' Inpatient Database (KID) was conducted. International Classification of Diseases, Ninth Revision, Clinical Modification codes for HIV and otolaryngologic diagnoses were used to query data from the triennially published KID files from 1997 to 2012. A subset analysis of infectious versus non-infectious admitting otolaryngologic diagnoses was conducted.

RESULTS

A total of 11,150 cases met the inclusion criteria. Of these cases, 21.8% were admitted for otolaryngologic manifestations, with 18.0% presenting with infectious symptomatology, 4.8% with noninfectious disease, and 1.0% with both. On average, patients presenting with infectious disease were younger (8.17 years vs. 9.65 years, P < .001). Patients in the South were significantly more likely to be admitted for infection (54.8% vs. 42.0%, P < .001), with non-infectious predominance in the Northeast and West. HIV-infected children in 1997 were more likely to present with infectious otolaryngologic disease (56.3% vs. 45.8%, P < .001); however, there has been a decrease in the prevalence of infectious head and neck presentations (46.5%, 19.9%, 11.5%, 6.7%, 3.7%, and 1.9% from 1997 to 2012), and a gradual shift toward noninfectious manifestation with notable differences in 2000 and 2012 (19.9% vs. 25.2%; P = .017; and 1.9% vs. 4.8%, P < .001, respectively).

CONCLUSIONS

Otolaryngologic disease accounts for nearly one-fifth of hospitalizations in HIV-infected children; however, rates of hospitalization as well as otolaryngologic manifestations have progressively decreased over time. HIV-infected children nowadays are more likely to present with noninfectious rather than infectious disease.

LEVEL OF EVIDENCE

NA Laryngoscope, 129:E377-E382, 2019.

Role of the lung microbiome in HIV pathogenesis

PURPOSE OF REVIEW

The purpose of this review is to summarize recent findings on the lung microbiome in HIV-infected patients and associated pulmonary diseases, and the relationship of airway microbial communities to metabolic and immune signatures within this patient population.

RECENT FINDINGS

The lung microbiome in HIV infection is a relatively new and rapidly developing field; early studies in the field produced inconclusive evidence as to whether HIV-infection changes the lower airway microbiome. More recent microbiome investigations have addressed these inconsistencies by incorporating systems biology approaches and laboratory models. Several investigations have now identified enrichment of Prevotella, Veillonella, and Streptococcus in the lower airways as consistent correlates of advanced HIV-infection and HIV-associated pulmonary diseases. These bacteria are associated with specific metabolic and immune profiles within the lung and circulation, providing the first indication that the lung microbiome may play a functional role in the pathogenesis of HIV-infection and HIV-associated pulmonary disease.

SUMMARY

This review summarizes knowledge to date on the lung microbiome in HIV infection, as well as challenges and accomplishments in the field within the last 2 years. Although the lung microbiome in HIV infection is still an emerging field, recent studies have formed a framework for future functional analysis of microbes in HIV pathogenesis.

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.

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.

The respiratory microbiome of HIV-infected individuals

INTRODUCTION

The respiratory tract is constantly exposed to various environmental and endogenous microbes; however, unlike other similar mucosal surfaces, there has been limited investigation of the microbiome of the respiratory tract.

AREAS COVERED

In this review, we summarize the current state of knowledge of the bacterial, fungal, and viral respiratory microbiomes during HIV infection and how the microbiome might relate to HIV-associated lung disease. Expert commentary: HIV infection is associated with alterations in the respiratory microbiome. The clinical implications of lung microbial dysbiosis are however currently unknown. Mechanistic studies are needed to establish causality between shifts in the respiratory microbiome and pulmonary complications in HIV-infected individuals.

The clinical implications of HIV infection and aging

The objectives of this study, presented as part of a plenary session at WW7 in Hyderabad, India were to review (i) the epidemiology and current clinical issues of HIV infection with regard to HIV and older populations and (ii) models for increased morbidity and mortality in older HIV-positive individuals with implications for clinical care. HIV infection for those in treatment has become a complex chronic disease in which end-organ injury and resulting morbidity, functional decline, and mortality do not have a single etiology but reflect cumulative loss of organ system reserve from multiple interacting sources leading to functional decline, organ system failure, and death. Emerging guidelines and recommendations suggest a need for increased awareness and treatment of the multifaceted needs of the aging HIV-infected patient.

How I treat patients with HIV-related hematological malignancies using hematopoietic cell transplantation

Hematopoietic cell transplantation (HCT) has now been shown to be safe and effective for selected HIV-infected patients with hematological malignancies. Autologous HCT is now the standard of care for patients with HIV-related lymphomas who otherwise meet standard transplant criteria. Limited data also support use of allogeneic HCT (alloHCT) in selected HIV-infected patients who meet standard transplant criteria. We recommend enrolling patients in clinical trials that offer access to CCR5Δ32 homozygous donors, if available. HIV-infected patients requiring HCT may also be considered for participation in trials evaluating the activity of gene-modified hematopoietic stem cells in conferring resistance to HIV infection. To be considered for HCT, patients must have HIV infection that is responsive to combination antiretroviral therapy (cART). Careful planning for the peri-HCT management of the cART can avoid risk of significant drug interactions and development of cART-resistant HIV. In general, we recommend against the use of boosted proteasome inhibitors and nonnucleotide reverse transcriptase inhibitors in the cART regimen, in favor of nucleoside reverse transcriptase inhibitors and integrase inhibitors (without cobicistat). After HCT, patients must be closely monitored for development of opportunistic infections (OI), such as cytomegalovirus. Prevention of OI should include prophylactic and pre-emptive antimicrobials.

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.

Long-term effects of severe acute malnutrition on lung function in Malawian children: a cohort study

Early nutritional insults may increase risk of adult lung disease. We aimed to quantify the impact of severe acute malnutrition (SAM) on spirometric outcomes 7 years post-treatment and explore predictors of impaired lung function.

Spirometry and pulse oximetry were assessed in 237 Malawian children (median age: 9.3 years) who had been treated for SAM and compared with sibling and age/sex-matched community controls. Spirometry results were expressed as z-scores based on Global Lung Function Initiative reference data for the African–American population.

Forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC) were low in all groups (mean FEV₁ z-score: −0.47 for cases, −0.48 for siblings, −0.34 for community controls; mean FVC z-score: −0.32, −0.38, and −0.15 respectively). There were no differences in spirometric or oximetry outcomes between SAM survivors and controls. Leg length was shorter in SAM survivors but inter-group sitting heights were similar. HIV positive status or female sex was associated with poorer FEV₁, by 0.55 and 0.31 z-scores, respectively.

SAM in early childhood was not associated with subsequent reduced lung function compared to local controls. Preservation of sitting height and compromised leg length suggest “thrifty” or “lung-sparing” growth. Female sex and HIV positive status were identified as potentially high-risk groups.

Despite stunting, survivors of acute malnutrition do not have worse lung function than controlshttp://ow.ly/2nvH308LroU

Non-infectious pulmonary disorders in HIV

INTRODUCTION

Since the advent of antiretroviral therapy (ART), non-infectious pulmonary disorders have become common comorbidities in the human immunodeficiency virus (HIV) positive population. Clinicians caring for those with HIV disease should be aware of the prevalence of non-infectious pulmonary disorders. A comprehensive understanding is required to diagnosis and manage these syndromes appropriately. Areas covered: This review focuses on the epidemiology, risk factors, pathogenesis, clinical feature and diagnosis, and treatment of HIV-related chronic obstructive pulmonary disease (COPD), lung cancer, pulmonary hypertension. Expert Commentary: The prevalence of COPD in the HIV population is frequent and requires appropriate diagnosis and treatment. HIV-positive individuals with lung cancer carry a poorer prognosis and require early diagnosis and treatment. A complex condition exists with pulmonary hypertension in the HIV population and requires a high degree of clinical suspicion for early diagnosis.

Mechanisms of HIV persistence in HIV reservoirs

The establishment and maintenance of HIV reservoirs that lead to persistent viremia in patients on antiretroviral drugs remains the greatest challenge of the highly active antiretroviral therapy era. Cellular reservoirs include resting memory CD4+ T lymphocytes, implicated as the major HIV reservoir, having a half-life of approximately 44 months while this is less than 6 hours for HIV in plasma. In some individuals, persistent viremia consists of invariant HIV clones not detected in circulating resting CD4+ T lymphocytes suggesting other possible sources of residual viremia. Some anatomical reservoirs that may harbor such cells include the brain and the central nervous system, the gastrointestinal tract and the gut-associated lymphoid tissue and other lymphoid organs, and the genital tract. The presence of immune cells and other HIV susceptible cells, occurring in differing compositions in anatomical reservoirs, coupled with variable and poor drug penetration that results in suboptimal drug concentrations in some sites, are all likely factors that fuel the continued low-level replication and persistent viremia during treatment. Latently, HIV-infected CD4+ T cells harboring replication-competent virus, HIV cell-to-cell spread, and HIV-infected T cell homeostatic proliferation due to chronic immune activation represent further drivers of this persistent HIV viremia during highly active antiretroviral therapy.

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.

Lower Respiratory Tract Infections

This review will focus on the infectious etiologies and more common noninfectious causes of lower respiratory tract syndromes among major immunosuppressed populations. The changing epidemiology of infections in the era of highly active antiretroviral therapy (HAART) in the case of HIV-positive patients and the impacts of both newer immune-suppressant therapies and anti-infective prophylaxis for other immunocompromised hosts will be discussed, with emphasis on diagnostic approaches and practice algorithms.