Objective To determine relationship of echocardiographic measures of pulmonary hypertension to lung function and inflammatory biomarkers in HIV-infected individuals. Design Cross-sectional study of 116 HIV-infected outpatients. Methods Doppler-echocardiography and pulmonary function testing were performed. Induced sputum and plasma cytokines, sputum cell counts and differentials, markers of peripheral T cell activation, and serum N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured. Univariate and multivariate analyses determined relationship of echocardiographic variables to pulmonary function, inflammation, and NT-proBNP. Results Mean estimated pulmonary artery systolic pressure (PASP) was 34.3 mmHg (SD 6.9) and mean tricuspid regurgitant jet velocity (TRV) was 2.5 m/sec (SD 0.32). Eighteen participants (15.5%) had PASP of at least 40 mmHg, and 9 (7.8%) had TRV of at least 3.0 m/sec. Elevated TRV was significantly associated with CD4 cell counts below 200 cells/μl and higher log HIV RNA levels. Forced expiratory volume in one second (FEV1) percent predicted, FEV1/forced vital capacity (FVC), and diffusing capacity for carbon monoxide (DLco) percent predicted were significantly lower in those with elevated PASP or TRV. Sputum interleukin-8, peripheral interleukin-8, peripheral interferon-γ levels, and CD8+ T-cell expression of CD69+ were associated increased with increasing PASP and TRV. Log NT-proBNP was significantly higher with increasing PASP and TRV. Left ventricular function was not associated with PASP or TRV. Conclusions Echocardiographic manifestations of pulmonary hypertension are common in HIV and are associated with respiratory symptoms, more advanced HIV disease, airway obstruction, abnormal DLco, and systemic and pulmonary inflammation. Pulmonary hypertension and COPD coexist in HIV and may arise secondary to common inflammatory mechanisms.

Background Translocation of gastrointestinal bacteria in HIV-infected individuals is associated with systemic inflammation, HIV progression, mortality, and co-morbidities. HIV-infected individuals are also susceptible to fungal infection and colonization, but whether fungal translocation occurs and influences HIV progression or co-morbidities is unknown. Methods Serum (1→3)-β-D-glucan was measured by a Limulus Amebocyte Lysate assay (Fungitell®) in 132 HIV-infected outpatients. Selected plasma cytokines and markers of peripheral T-cell activation were measured. Pulmonary function testing and Doppler-echocardiography were performed. Relationship of high (≥40pg/ml) and low (<40pg/ml) levels of (1→3)-β-D-glucan with HIV-associated variables, inflammation markers, and pulmonary function and pulmonary hypertension measures were determined. Results Forty-eight percent had detectable (1→3)-β-D-glucan, and 16.7% had high levels. Individuals with high (1→3)-β-D-glucan were more likely to have CD4 counts below 200 cells/μl (31.8% vs. 8.4%, p=0.002), had higher log10 HIV viral levels (2.85 vs. 2.13 log copies/ml, p=0.004), and were less likely to use ART (68.2% vs. 90.0%, p=0.006). Plasma IL-8 (p=0.033), TNF-α (p=0.029), and CD8+CD38+ (p=0.046) andCD8+HLA-DR+ (p=0.029) were also increased with high levels. Abnormalities in diffusing capacity (p=0.041) and in pulmonary artery pressures (p=0.006 for pulmonary artery systolic pressure and 0.013 for tricuspid regurgitant velocity) were more common in those with high (1→3)-β-D-glucan. Conclusions We found evidence of peripheral fungal cell wall polysaccharides in an HIV-infected cohort. We also demonstrated an association between high serum (1→3)-β-D-glucan, HIV-associated immunosuppression, inflammation, and cardiopulmonary co-morbidity. These results implicate a new class of pathogen in HIV-associated microbial translocation and suggest a role in HIV progression and co-morbidities.

Background Despite the high prevalence of respiratory symptoms and obstructive lung disease in HIV-infected persons, the prevalence of bronchodilator reversibility (BDR) and asthma has not been systematically studied during the era of combination antiretroviral therapy (ART). Objective To determine the prevalence of asthma diagnosis and related pulmonary function abnormalities in an HIV-infected cohort and to identify potential mechanisms. Methods A cross-sectional analysis of 223 HIV-infected individuals with data on respiratory symptoms and diagnoses, pulmonary function, sputum cell counts, and asthma-related cytokines and chemokines in serum/sputum. Results Doctor-diagnosed asthma was present in 46 (20.6%) and BDR (≥200ml and ≥12% increase in FEV1 or FVC) in 20 participants (9.0%). Pulmonary symptoms and function were worse in those with doctor-diagnosed asthma. Doctor-diagnosed asthma was independently associated with female sex (p=0.04), body mass index >29.6kg/m2 (vs.<29.6kg/m2) (p=0.03), history of bacterial or Pneumocystis pneumonia (p=0.01), and with not currently taking ART (p=0.04), and in univariate analysis with parental history of asthma (n=180; p=0.004). High sputum eosinophil percentages (>2.3% based on the highest decile) were more likely in those with doctor-diagnosed asthma (p=0.02) or BDR (p=0.02). Doctor-diagnosed asthma tended to be more common with high sputum IL-4 (p=0.02) and RANTES (p=0.02), while BDR was associated with high plasma macrophage inflammatory protein (MIP)-1α (p=0.002), and sputum MIP-1β levels (p=0.001). Conclusion Asthma diagnosis and BDR are prevalent in an HIV-infected outpatient cohort, and associations with family history, obesity, allergic inflammation, prior infection, the absence of ART, and elevated HIV-stimulated cytokines suggest possible mechanisms of HIV-associated asthma.

Chronic obstructive pulmonary disease (COPD) is a complex disease, the pathogenesis of which remains incompletely understood. Colonization with Pneumocystis jirovecii may play a role in COPD pathogenesis; however, the mechanisms by which such colonization contributes to COPD are unknown. The objective of this study was to determine lung gene expression profiles associated with Pneumocystis colonization in patients with COPD to identify potential key pathways involved in disease pathogenesis. Using COPD lung tissue samples made available through the Lung Tissue Research Consortium (LTRC), Pneumocystis colonization status was determined by nested PCR. Microarray gene expression profiles were performed for each sample and the profiles of colonized and non-colonized samples compared. Overall, 18 participants (8.5%) were Pneumocystis-colonized. Pneumocystis colonization was associated with fold increase in expression of four closely related genes: INF-γ and the three chemokine ligands CXCL9, CXCL10, and CXCL11. These ligands are chemoattractants for the common cognate receptor CXCR3, which is predominantly expressed on activated Th1 T-lymphocytes. Although these ligand–receptor pairs have previously been implicated in COPD pathogenesis, few initiators of ligand expression and subsequent lymphocyte trafficking have been identified: our findings implicate Pneumocystis as a potential trigger. The finding of upregulation of these inflammatory genes in the setting of Pneumocystis colonization sheds light on infectious-immune relationships in COPD.

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