The effect of focused lung ultrasonography on antibiotic prescribing in patients with acute lower respiratory tract infections in Danish general practice: study protocol for a pragmatic randomized controlled trial (PLUS-FLUS).

BACKGROUND: The use of antibiotics is a key driver of antimicrobial resistance and is considered a major threat to global health. In Denmark, approximately 75% of antibiotic prescriptions are issued in general practice, with acute lower respiratory tract infections (LRTIs) being one of the most common indications. Adults who present to general practice with symptoms of acute LRTI often suffer from self-limiting viral infections. However, some patients have bacterial community-acquired pneumonia (CAP), a potential life-threatening infection, that requires immediate antibiotic treatment. Importantly, no single symptom or specific point-of-care test can be used to discriminate the various diagnoses, and diagnostic uncertainty often leads to (over)use of antibiotics. At present, general practitioners (GPs) lack tools to better identify those patients who will benefit from antibiotic treatment. The primary aim of the PLUS-FLUS trial is to determine whether adults who present with symptoms of an acute LRTI in general practice and who have FLUS performed in addition to usual care are treated less frequently with antibiotics than those who only receive usual care. METHODS: Adults (≥ 18 years) presenting to general practice with acute cough (< 21 days) and at least one other symptom of acute LRTI, where the GP suspects a bacterial CAP, will be invited to participate in this pragmatic randomized controlled trial. All participants will receive usual care. Subsequently, participants will be randomized to either the control group (usual care) or to an additional focused lung ultrasonography performed by the GP (+ FLUS). The primary outcome is the proportion of participants with antibiotics prescribed at the index consultation (day 0). Secondary outcomes include comparisons of the clinical course for participants in groups. DISCUSSION: We will examine whether adults who present with symptoms of acute LRTI in general practice, who have FLUS performed in addition to usual care, have antibiotics prescribed less frequently than those given usual care alone. It is highly important that a possible reduction in antibiotic prescriptions does not compromise patients' recovery or clinical course, which we will assess closely. TRIAL REGISTRATION: ClinicalTrials.gov NCT06210282. Registered on January 17, 2024.

Thoracic Ultrasound in Lung Transplantation-Insights in the Field.

The use of thoracic ultrasound (TUS) is a novel and dynamic diagnostic and monitoring modality that has shown remarkable advances within the last decade, with several published papers investigating its role within the field of lung transplantation. The aim of this current opinion review is to review the existing literature on the role of TUS in all stages of LTx, from in-donor lung evaluation to graft assessment on ex vivo lung perfusion and in the short- and long-term follow-up after LTx.

Remote dielectric sensing to detect acute heart failure in patients with dyspnoea: a prospective observational study in the emergency department.

Aims: Remote dielectric sensing (ReDS) enables quick estimation of lung fluid content. To examine if ReDS is superior to other methods in detecting acute heart failure. Methods and results: We included consecutive patients with dyspnoea from the emergency departments at Bispebjerg Hospital, Copenhagen, and performed ReDS, low-dose chest computed tomography (CT), echocardiogram, lung ultrasound, NT-Pro-brain natriuretic peptide (NT-proBNP), and a Boston score evaluation (chest X-ray and clinical signs). ReDS values >35% were used as a cut-off to diagnose pulmonary congestion. Acute heart failure was adjudicated by experts' review of health records but independently of ReDS values. Sub-analyses investigated ReDS in acute heart failure patients with congestion on CT. We included 97 patients within a median of 4.8 h from admittance: 25 patients (26%) were ReDS-positive and 39 (40%) had adjudicated acute heart failure (21 with and 18 without CT congestion). Heart failure patients had median ReDS 33%, left ventricular ejection fraction 48%, and NT-proBNP 2935 ng/L. A positive ReDS detected heart failure with 46% sensitivity, 88% specificity, and 71% accuracy. The AUC for ReDS was like the Boston score (P = 0.88) and the lung ultrasound score (P = 0.74). CT-congested heart failure patients had higher ReDS values than patients without heart failure (median 38 vs. 28%, P < 0.001). Heart failure patients without CT-congestion had ReDS values like patients without heart failure (mean 30 vs. 28%, P = 0.07). Conclusion: ReDS detects acute heart failure similarly to the Boston score and lung ultrasound score, and ReDS primarily identifies the acute heart failure patients who have congestion on a chest CT.

Achromobacter spp. in a Cohort of Non-Selected Pre- and Post-Lung Transplant Recipients.

Achromobacter is an opportunistic pathogen that mainly causes chronic lung infections in cystic fibrosis (CF) patients and is associated with increased mortality. Little is known about Achromobacter spp. in the lung transplant recipient (LTXr) population. We aimed at describing rates of Achromobacter spp. infection in LTXr prior to, in relation to, and after transplantation, as well as all-cause mortality proportion in infected and uninfected LTXr. We included 288 adult LTXr who underwent lung transplantation (LTX) between 1 January 2010 and 31 December 2019 in Denmark. Bronchoalveolar lavage was performed at regular intervals starting two weeks after transplantation. Positive cultures of Achromobacter spp. were identified in nationwide microbiology registries, and infections were categorized as persistent or transient, according to the proportion of positive cultures. A total of 11 of the 288 LTXr had transient (n = 7) or persistent (n = 4) Achromobacter spp. infection after LTX; CF was the underlying disease in 9 out of 11 LTXr. Three out of the four patients, with persistent infection after LTX, also had persistent infection before LTX. The cumulative incidence of the first episode of infection one year after LTX was 3.8% (95% CI: 1.6-6.0). The incidence rates of transient and persistent infection in the first year after LTX were 27 (12-53) and 15 (5-37) per 1000 person-years of follow-up, respectively. The all-cause mortality proportion one year after LTX was 27% in the Achromobacter spp. infected patients and 12% in the uninfected patients (p = 0.114). Achromobacter spp. mainly affected LTXr with CF as the underlying disease and was rare in non-CF LTXr. Larger studies are needed to assess long-term outcomes of Achromobacter spp. in LTXr.

Lung Ultrasound to Phenotype Chronic Lung Allograft Dysfunction in Lung Transplant Recipients. A Prospective Observational Study.

BACKGROUND: Bronchiolitis obliterans syndrome (BOS) and restrictive allograft syndrome (RAS) are two distinct phenotypes of chronic lung allograft dysfunction (CLAD) in lung transplant (LTx) recipients. Contrary to BOS, RAS can radiologically present with a pleuroparenchymal fibroelastosis (PPFE) pattern. This study investigates lung ultrasound (LUS) to identify potential surrogate markers of PPFE in order to distinguish CLAD phenotype RAS from BOS. METHODS: A prospective cohort study performed at a National Lung Transplantation Center during June 2016 to December 2017. Patients were examined with LUS and high-resolution computed tomography of the thorax (HRCT). RESULTS: Twenty-five CLAD patients (72% males, median age of 54 years) were included, corresponding to 19/6 BOS/RAS patients. LUS-identified pleural thickening was more pronounced in RAS vs. BOS patients (5.6 vs. 2.9 mm) compatible with PPFE on HRCT. LUS-identified pleural thickening as an indicator of PPFE in RAS patients' upper lobes showed a sensitivity of 100% (95% CI; 54-100%), specificity of 100% (95% CI; 82-100%), PPV of 100% (95% CI; 54-100%), and NPV of 100% (95% CI; 82-100%). CONCLUSION: Apical pleural thickening detected by LUS and compatible with PPFE on HRCT separates RAS from BOS in patients with CLAD. We propose LUS as a supplementary tool for initial CLAD phenotyping.

Bacterial Re-Colonization Occurs Early after Lung Transplantation in Cystic Fibrosis Patients.

Most cystic fibrosis (CF) patients referred for lung transplantation are chronically infected with Gram-negative opportunistic pathogens. It is well known that chronic infections in CF patients have a significant impact on lung-function decline and survival before transplantation. The rate and timing of re-colonization after transplantation have been described, but the impact on survival after stratification of bacteria is not well elucidated. We did a single-center retrospective analysis of 99 consecutive CF patients who underwent lung transplantation since the beginning of the Copenhagen Lung Transplant program in 1992 until October 2014. Two patients were excluded due to re-transplantation. From the time of CF diagnosis, patients had monthly sputum cultures. After transplantation, CF-patients had bronchoscopy with bronchoalveolar lavage at 2, 4, 6 and 12 weeks and 6, 12, 18 and 24 months after transplantation, as well as sputum samples if relevant. Selected culture results prior to and after transplantation were stored. We focused on colonization with the most frequent bacteria: Pseudomonas aeruginosa (PA), Stenotrophomonas maltophilia (SM), Achromobacter xylosoxidans (AX) and Burkholderia cepacia complex (BCC). Pulsed-field gel electrophoresis (PFGE) was used to identify clonality of bacterial isolates obtained before and after lung transplantation. Time to re-colonization was defined as the time from transplantation to the first positive culture with the same species. Seventy-three out of 97 (75%) had sufficient culture data for analyses with a median of 7 (1-91) cultures available before and after transplantation. Median colonization-free survival time was 23 days until the first positive culture after transplantation. After 2 years, 59 patients (81%) were re-colonized, 33 (48.5%) with PA, 7 (10.3%) with SM, 12 (17.6%) with AX, and 7 (10.3%) with BCC. No difference in survival was observed between the patients colonized within the first 2 years and those not colonized. Re-colonization of bacteria in the lower airways occurred at a median of 23 days after transplantation in our cohort. In our patient cohort, survival was not influenced by re-colonization or bacterial species.

Lung Ultrasound in the Assessment of Pulmonary Complications After Lung Transplantation.

INTRODUCTION: Lung ultrasound (LUS) has a high diagnostic accuracy for identifying frequent conditions in the post-operative phase after lung transplantation (LTx). This study aimed to investigate the feasibility and clinical ability of LUS to identify pulmonary complications such as pleural effusions and pneumonias in the early postoperative phase after LTx. METHODS: A prospective cohort study of lung transplant recipients who consecutively underwent single LTx (SLTx) or double LTx (DLTx) at the National Lung Transplantation Center in Denmark from May 1 to October 31, 2015 was conducted. LUS was performed at four time points corresponding to post-transplant day 3, and weeks 2, 6, and 12 (LUS #1-4) to detect and monitor variation in pathological LUS findings over time. Concurrent with LUS #4, a high-resolution computed tomography examination of the thorax (HRCT) was also performed. RESULTS: 14 patients (1 SLTx/13 DLTx, 7 (50 %) women, mean age: 50.4 years) who had undergone the four prespecified LUS examinations were included. Pleural effusion was the most common condition and most pronounced at post-LTx week 2. Findings consistent with pneumonia increased during week 2 and subsequently decreased. Corresponding to LUS #1, 2, 3, and 4, pleural effusion occurred in 85.7 %, 92.9 %, 85.7 %, and 78.6 %, and pneumonia in 21.4 %, 28.6 %, 14.3 %, and 14.3 %, respectively. HRCT findings at post-LTx week 12 were predominantly presented by unspecific ground glass opacities. CONCLUSION: In a post-LTx setting, LUS represents a clinical novelty as a feasible diagnostic and monitoring tool to identify pathological pulmonary complications in the early post-operative phase.

[The first 25 years of lung transplantations in Denmark].

Lung transplantation (LTx) has been performed in Denmark since 1992, and chronic obstructive pulmonary disease and interstitial lung diseases are the major indications. All candidates are subject to an intensive evaluation before being accepted for LTx. Follow-up after transplantation is life-long and includes immunosuppressive medication with a high risk of side effects. The median survival in Denmark is 7.0 years. Chronic rejection is common, diagnosed by declining lung function, and it is the most important factor for morbidity and mortality. LTx requires dedicated personnel in an interdisciplinary organisation.

Effect of Donor Age on Outcome of Lung Transplantation Stratified by Recipient Diagnosis: A Nordic Multicenter Study.

BACKGROUND: Organs from older donors are increasingly used in lung transplantation, and studies have demonstrated that this could be safe in selected recipients. However, which recipient groups that have the largest benefit of older organs are unclear. This multicenter study reviews all bilateral lung transplantations (BLTx) from donors 55 years or older stratified by recipient diagnosis and compares outcomes with transplantations from younger donors. METHODS: All BLTx recipients (excluding retransplantation) at 5 Scandiatransplant centers between 2000 and 2013 were included (n = 913). Recipients were stratified to diagnosis groups including cystic fibrosis (CF), chronic obstructive pulmonary disease (COPD), interstitial lung disease (ILD), and "other." Intensive care unit (ICU) length of stay (LOS) and survival were assessed. RESULTS: Overall, there was no difference in survival among patients transplanted from donors 55 years or older compared with younger donors. However, in CF recipients, donor age 55 years or older was associated with inferior survival (P = 0.014), and this remained significant in a multivariate model (hazard ratio, 5.0; 95% confidence interval, 1.8-14.1; P = 0.002). There was no significant effect of donor age on survival in recipients with COPD, ILD, or in the "other" group in multivariate models. Utilization of older donors was associated with increased ICU LOS for recipients with CF and ILD, but not in the COPD or "other" group. CONCLUSIONS: The BLTx recipients with CF had inferior survival and longer ICU LOS when receiving organs from donors 55 years or older. Recipients with COPD, ILD, or in the "other" group did not have inferior survival in multivariate models.

Long-term persistence of human donor alveolar macrophages in lung transplant recipients.

BACKGROUND: Alveolar macrophages (AMFs) are critical regulators of lung function, and may participate in graft rejection following lung transplantation. Recent studies in experimental animals suggest that most AMFs are self-maintaining cells of embryonic origin, but knowledge about the ontogeny and life span of human AMFs is scarce. METHODS: To follow the origin and longevity of AMFs in patients with lung transplantation for more than 100 weeks, we obtained transbronchial biopsies from 10 gender-mismatched patients with lung transplantation. These were subjected to combined in situ hybridisation for X/Y chromosomes and immunofluorescence staining for macrophage markers. Moreover, development of AMFs in humanised mice reconstituted with CD34+ umbilical cord-derived cells was assessed. RESULTS: The number of donor-derived AMFs was unchanged during the 2 year post-transplantation period. A fraction of the AMFs proliferated locally, demonstrating that at least a subset of human AMFs have the capacity to self-renew. Lungs of humanised mice were found to abundantly contain populations of human AMFs expressing markers compatible with a monocyte origin. Moreover, in patients with lung transplantation we found that recipient monocytes seeded the alveoli early after transplantation, and showed subsequent phenotypical changes consistent with differentiation into proliferating mature AMFs. This resulted in a stable mixed chimerism between donor and recipient AMFs throughout the 2-year period. CONCLUSIONS: The finding that human AMFs are maintained in the lung parenchyma for several years indicates that pulmonary macrophage transplantation can be a feasible therapeutic option for patients with diseases caused by dysfunctional AMFs. Moreover, in a lung transplantation setting, long-term persistence of donor AMFs may be important for the development of chronic graft rejection.

Recurrence of sarcoid granulomas in lung transplant recipients is common and does not affect overall survival.

BACKGROUND: Sarcoidosis represents 2,5% of all indications for lung transplantation and criteria are generally assumed to be the same as for pulmonary fibrosis. Recurrence of granulomas in transplanted lungs has earlier been proved to derive from recipient immune cells, but its role in relation to lung function and overall survival after lung transplantation remains uncertain. OBJECTIVE: To identify recurrent granuloma in transbronchial biopsies in patients receiving lung transplant because of sarcoidosis, and relate the findings to overall survival and lung function. DESIGN: A total of 620 patients were transplanted at this centre from 1992 until august 2012. This study comprised all patients (n=25) transplanted due to pulmonary sarcoidosis. Lung functions, trans-bronchial biopsies, and survival were compared in patients with and without recurrence of granulomas. Granulomas were defined as non-necrotizing epitheloid granulomas with multinucleated giant cells according to standard criteria (formation of epitheloid giant cells) without presence of infection. CONCLUSIONS: Approximately 30% of lung transplant recipients due to sarcoidosis have recurrence of sarcoid granulomas. Recurrence of granulomas does not affect overall survival or lung function.