Fraction of exhaled nitric oxide is higher in liver transplant recipients than in controls from the general population: a cohort study.

Background: Fraction of exhaled nitric oxide with an expiratory flow of 50 mL/s (FENO50) is a biomarker of eosinophilic airway inflammation. Liver transplant recipients have an increased risk of pulmonary infections, but little is known about the burden of chronic pulmonary diseases in this group. We aimed to assess the prevalence of elevated FENO50 in liver transplant recipients and compare it to controls from the general population. Methods: FENO50 was measured in 271 liver transplant recipients from The Danish Comorbidity in Liver Transplant Recipients (DACOLT) study and 1,018 age- and sex-matched controls from The Copenhagen General Population Study (CGPS). Elevated FENO50 was defined as ≥25 or ≥50 parts per billion (ppb). The analyses were adjusted for known and suspected confounders. Results: The median age of the liver transplant recipients was 55 years (interquartile range (IQR) 46-64), and 58% were men. The liver transplant recipients had a higher median FENO50 than the controls [16 ppb (IQR 10-26) vs. 13 ppb (IQR 8-18.), p < 0.001]. Furthermore, the liver transplant recipients had a higher prevalence of elevated FENO50 (for FENO50 ≥25 ppb 27% vs. 11%, p < 0.001 and ≥50 ppb 4% vs. 2%, p = 0.02). The results were similar after adjusting for age, sex, smoking status, use of airway medication, and blood eosinophil counts [the adjusted odds ratio (OR) for FENO50 ≥25 ppb was 3.58 (95% CI: 2.50-5.15, p < 0.0001) and the adjusted OR for FENO50 ≥50 ppb was 3.14 (95% CI: 1.37-7.20, p = 0.007)]. Conclusion: The liver transplant recipients had elevated FENO50, implying increased eosinophilic airway inflammation. The clinical impact of this finding needs further investigation.

Elevated Levels of Interleukin-1ß and Interleukin-10 Are Associated With Faster Lung Function Decline in People With Well-Treated Human Immunodeficiency Virus.

BACKGROUND: People with human immunodeficiency virus (PWH) have an increased risk of chronic lung diseases and chronic inflammation. We aimed to investigate if inflammatory markers and monocyte activation are associated with faster lung function decline in PWH. METHODS: We included 655 PWH from the Copenhagen Comorbidity in HIV Infection (COCOMO) Study. Eligible participants were aged ≥25 years and had 2 spirometries separated by >2 years. Inflammatory markers (interleukin [IL]-1ß, IL-2, IL-6, IL-10, tumor necrosis factor-α, and interferon-γ) were measured at baseline by Luminex, and soluble CD14 and soluble CD163 by enzyme-linked immunosorbent assay. Using linear mixed models, we investigated whether elevated cytokine levels were associated with faster lung function decline. RESULTS: The majority of PWH were males (85.2%) with undetectable viral replication (95.3%). We found a faster decline in forced expiratory volume in 1 second (FEV1) in PWH with elevated IL-1ß and IL-10, with an additional decline of 10.3 mL/year (95% confidence interval [CI], 2.1-18.6; P = .014) and 10.0 mL/year (95% CI, 1.8-18.2; P = .017), respectively. We found no interaction between smoking and IL-1ß or IL-10 on FEV1 decline. CONCLUSIONS: Elevated IL-1ß and IL-10 were independently associated with faster lung function decline in PWH, suggesting that dysregulated systemic inflammation may play a role in the pathogenesis of chronic lung diseases.

Prevalence of emphysema in people living with human immunodeficiency virus in the current combined antiretroviral therapy era: A systematic review.

Before introducing combination antiretroviral therapy (cART), a higher prevalence of emphysema in people living with HIV (PLWH) than in the background population was reported. This systematic literature review aimed to investigate the prevalence of emphysema in PLWH and to compare the prevalence between PLWH and controls in the current cART era. A systematic literature search was conducted in PubMed, EMBASE, Scopus, and Web of Science (WOS), searching for "human immunodeficiency virus (HIV)" and "emphysema" from January 1, 2000 to March 10, 2021. Eligible studies were published after the introduction of cART, included PLWH, and reported the prevalence of emphysema. A total of 17 studies were included, and nine studies also included controls. The weighted average prevalence of emphysema in PLWH was 23% (95% CI: 16-30). In studies including both PLWH and controls the weighted average prevalence were 22% (95% CI: 10-33) and 9.7% (95% CI: 2.3-17), respectively (p = 0.052). The prevalence of emphysema in never-smoking PLWH and controls was just reported in one study and was 18 and 4%, respectively (p < 0.01). Thirteen of the studies had a moderate risk of bias, mainly due to selection of patients. A tendency to higher prevalence of emphysema was found in PLWH in comparison to controls in the current cART era. However, in the included studies, the definition of emphysema varied largely. Thus, to have a clear overview of the prevalence, further studies with well-designed cohorts of PLWH and controls are warranted.

Corticosteroid Resistance in Smokers-A Substudy Analysis of the CORTICO-COP Randomised Controlled Trial.

The CORTICO-COP trial showed that eosinophil-guided corticosteroid-sparing treatment for acute exacerbation of chronic obstructive pulmonary disease was non-inferior to standard of care and decreased the accumulated dose of systemic corticosteroids that patients were exposed to by approximately 60%. Smoking status has been shown to affect corticosteroid responsiveness. This post hoc analysis investigated whether eosinophil-guided treatment is non-inferior to conventional treatment in current smokers. The main analysis of current smokers showed no significant difference in the primary endpoint, days alive, and out of hospital within 14 days between the control group (mean, 9.8 days; 95% confidence interval (CI), 8.7-10.8) and the eosinophil-guided group (mean, 8.7 days; 95% CI, 7.5-9.9; p = 0.34). Secondary analyses of the number of exacerbations or deaths, the number of intensive care unit admissions or deaths, lung function improvement, and change in health-related quality of life also showed no significant differences between the two groups. The results of a sensitivity analysis of ex-smokers are consistent with the main analysis. Our results suggest that eosinophil-guided treatment is non-inferior to standard of care in current smokers and ex-smokers. Because data on the impact of smoking status on eosinophil-guided treatments are sparse, more randomised trials are needed to confirm our results.

Procalcitonin-guided Antibiotic Treatment in Patients With Positive Blood Cultures: A Patient-level Meta-analysis of Randomized Trials.

BACKGROUND: Whether procalcitonin (PCT)-guided antibiotic management in patients with positive blood cultures is safe remains understudied. We performed a patient-level meta-analysis to investigate effects of PCT-guided antibiotic management in patients with bacteremia. METHODS: We extracted and analyzed individual data of 523 patients with positive blood cultures included in 13 trials, in which patients were randomly assigned to receive antibiotics based on PCT levels (PCT group) or a control group. The main efficacy endpoint was duration of antibiotic treatment. The main safety endpoint was mortality within 30 days. RESULTS: Mean duration of antibiotic therapy was significantly shorter for 253 patients who received PCT-guided treatment than for 270 control patients (-2.86 days [95% confidence interval [CI], -4.88 to -.84]; P = .006). Mortality was similar in both arms (16.6% vs 20.0%; P = .263). In subgroup analyses by type of pathogen, we noted a trend of shorter mean antibiotic durations in the PCT arm for patients infected with gram-positive organisms or Escherichia coli and significantly shorter treatment for subjects with pneumococcal bacteremia. In analysis by site of infection, antibiotic exposure was shortened in PCT subjects with Streptococcus pneumoniae respiratory infection and those with E. coli urogenital infections. CONCLUSIONS: This meta-analysis of patients with bacteremia receiving PCT-guided antibiotic management demonstrates lower antibiotic exposure without an apparent increase in mortality. Few differences were demonstrated in subgroup analysis stratified by type or site of infection but notable for decreased exposure in patients with pneumococcal pneumonia and E. coli urogenital infections.

Procalcitonin-guided antibiotic therapy algorithms for different types of acute respiratory infections based on previous trials.

INTRODUCTION: Although evidence indicates that use of procalcitonin to guide antibiotic decisions for the treatment of acute respiratory infections (ARI) decreases antibiotic consumption and improves clinical outcomes, algorithms used within studies had differences in PCT cut-off points and frequency of testing. We therefore analyzed studies evaluating procalcitonin-guided antibiotic therapy and propose consensus algorithms for different respiratory infection types. Areas covered: We systematically searched randomized-controlled trials (search strategy updated on February 2018) on procalcitonin-guided antibiotic therapy of ARI in adults using a pre-specified Cochrane protocol and analyzed algorithms from 32 trials that included 10,285 patients treated in primary care settings, emergency departments (ED), and intensive care units (ICU). We derived consensus algorithms for use of procalcitonin by the type of ARI including community-acquired pneumonia, bronchitis, chronic obstructive pulmonary disease or asthma exacerbation, sepsis, and post-operative sepsis due to respiratory infection. Consensus algorithm recommendations differ with regard to timing of treatment (i.e. timing of initiation in low-risk patients or discontinuation in high-risk patients) and procalcitonin cut-off points for the recommendation/strong recommendation to discontinue antibiotics (≤ 0.25/≤ 0.1 µg/L in ED and inpatients, ≤ 0.5/≤ 0.25 µg/L in ICU patients, and reduction by ≥ 80% from peak levels in sepsis patients). Expert commentary: Our proposed algorithms may facilitate safe and efficient implementation of procalcitonin-guided antibiotic protocols in diverse healthcare settings. Still, the decision about initiation and cessation of antibiotic treatment remains a clinical decision based on the patient assessment and the severity of illness and use of procalcitonin should not delay empirical treatment in high risk situations.

Effect of procalcitonin-guided antibiotic treatment on mortality in acute respiratory infections: a patient level meta-analysis.

BACKGROUND: In February, 2017, the US Food and Drug Administration approved the blood infection marker procalcitonin for guiding antibiotic therapy in patients with acute respiratory infections. This meta-analysis of patient data from 26 randomised controlled trials was designed to assess safety of procalcitonin-guided treatment in patients with acute respiratory infections from different clinical settings. METHODS: Based on a prespecified Cochrane protocol, we did a systematic literature search on the Cochrane Central Register of Controlled Trials, MEDLINE, and Embase, and pooled individual patient data from trials in which patients with respiratory infections were randomly assigned to receive antibiotics based on procalcitonin concentrations (procalcitonin-guided group) or control. The coprimary endpoints were 30-day mortality and setting-specific treatment failure. Secondary endpoints were antibiotic use, length of stay, and antibiotic side-effects. FINDINGS: We identified 990 records from the literature search, of which 71 articles were assessed for eligibility after exclusion of 919 records. We collected data on 6708 patients from 26 eligible trials in 12 countries. Mortality at 30 days was significantly lower in procalcitonin-guided patients than in control patients (286 [9%] deaths in 3336 procalcitonin-guided patients vs 336 [10%] in 3372 controls; adjusted odds ratio [OR] 0·83 [95% CI 0·70 to 0·99], p=0·037). This mortality benefit was similar across subgroups by setting and type of infection (pinteractions>0·05), although mortality was very low in primary care and in patients with acute bronchitis. Procalcitonin guidance was also associated with a 2·4-day reduction in antibiotic exposure (5·7 vs 8·1 days [95% CI -2·71 to -2·15], p<0·0001) and a reduction in antibiotic-related side-effects (16% vs 22%, adjusted OR 0·68 [95% CI 0·57 to 0·82], p<0·0001). INTERPRETATION: Use of procalcitonin to guide antibiotic treatment in patients with acute respiratory infections reduces antibiotic exposure and side-effects, and improves survival. Widespread implementation of procalcitonin protocols in patients with acute respiratory infections thus has the potential to improve antibiotic management with positive effects on clinical outcomes and on the current threat of increasing antibiotic multiresistance. FUNDING: National Institute for Health Research.