Divergent airway microbiomes in lung transplant recipients with or without pulmonary infection.

BACKGROUND: Lung transplant (LTx) recipients are at increased risk for airway infections, but the cause of infection is often difficult to establish with traditional culture-based techniques. The objectives of the study was to compare the airway microbiome in LTx patients with and without ongoing airway infection and identify differences in their microbiome composition. METHODS: LTx recipients were prospectively followed with bronchoalveolar lavage (BAL) during the first year after transplantation. The likelihood of airway infection at the time of sampling was graded based on clinical criteria and BAL cultures, and BAL fluid levels of the inflammatory markers heparin-binding protein (HBP), IL-1ß and IL-8 were determined with ELISA. The bacterial microbiome of the samples were analysed with 16S rDNA sequencing and characterized based on richness and evenness. The distance in microbiome composition between samples were determined using Bray-Curtis and weighted and unweighted UniFrac. RESULTS: A total of 46 samples from 22 patients were included in the study. Samples collected during infection and samples with high levels of inflammation were characterized by loss of bacterial diversity and a significantly different species composition. Burkholderia, Corynebacterium and Staphylococcus were enriched during infection and inflammation, whereas anaerobes and normal oropharyngeal flora were less abundant. The most common findings in BAL cultures, including Pseudomonas aeruginosa, were not enriched during infection. CONCLUSION: This study gives important insights into the dynamics of the airway microbiome of LTx recipients, and suggests that lung infections are associated with a disruption in the homeostasis of the microbiome.

Heparin-binding protein, lysozyme, and inflammatory cytokines in bronchoalveolar lavage fluid as diagnostic tools for pulmonary infection in lung transplanted patients.

Pulmonary infection is a common complication after lung transplantation, and early detection is crucial for outcome. However, the condition can be clinically difficult to diagnose and to distinguish from rejection. The aim of this prospective study was to evaluate heparin-binding protein (HBP), lysozyme, and the cytokines interleukin (IL)-1ß, IL-6, IL-8, IL-10 and tumor necrosis factor (TNF) in bronchoalveolar lavage fluid (BALF) as potential biomarkers for pulmonary infection in lung-transplanted patients. One hundred thirteen BALF samples from 29 lung transplant recipients were collected at routine scheduled bronchoscopies at 3 and 6 months, or on clinical indication. Samples were classified into no, possible, probable, or definite infection at the time of sampling. Rejection was defined by biopsy results. HBP, lysozyme, and cytokines were analyzed in BALF and correlated to likelihood of infection and rejection. All biomarkers were significantly increased in BALF during infection, whereas patients with rejection presented low levels that were comparable to noninfection samples. HBP, IL-1ß, and IL-8 were the best diagnostic markers of infection with area under the receiver-operating characteristic curve values of 0.88, 0.91, and 0.90, respectively. In conclusion, HBP, IL-1ß, and IL-8 could be useful diagnostic markers of pulmonary infection in lung-transplanted patients.

Microbiological findings in bronchoalveolar lavage fluid from lung transplant patients in Sweden.

BACKGROUND: Lung transplant patients experience a high risk of airway infections and microbial colonization of the lung due to constant exposure to the environment through inhaled microorganisms, denervation, reduced ciliary transport, and decreased cough. METHODS: In this nationwide prospective study on Swedish lung transplant patients, we evaluated the microbiological panorama of bacteria, fungi, and virus found in bronchoalveolar lavage fluid (BALF) obtained the first year after lung transplantation (LTx). Differences in microbiological findings depending of concomitant signs of infection and background factors were assessed. RESULTS: A total of 470 bronchoscopies from 126 patients were evaluated. Sixty-two percent (n = 293) of BALF samples had positive microbiological finding(s). Forty-six percent (n = 217) had bacterial growth, 29% (n = 137) fungal growth, and 9% (n = 43) were positive in viral PCR. In 38% of BALF samples (n = 181), a single microbe was found, whereas a combination of bacteria, fungi or virus was found in 24% (n = 112) of bronchoscopies. The most common microbiological findings were Candida albicans, Pseudomonas aeruginosa and coagulase negative Staphylococcus (in 42 (33%), 36 (29%), and 25 (20%) patients, respectively). Microbiological findings were similar in BALF from patients with and without signs of lung infection and the frequency of multidrug resistant (MDR) bacteria was low. No significant association was found between background factors and time to first lung infection. CONCLUSION: This study gives important epidemiologic insights and reinforces that microbiological findings have to be evaluated in the light of clinical symptoms and endobronchial appearance in the assessment of lung infections in lung transplant patients.

Prospective evaluation of a combination of fungal biomarkers for the diagnosis of invasive fungal disease in high-risk haematology patients.

We prospectively evaluated a combination of fungal biomarkers in adult haematology patients with focus on their clinical utility at different time points during the course of infection. In total, 135 patients were monitored once to twice weekly for serum (1-3)-ß-d-glucan (BG), galactomannan (GM), bis-methyl-gliotoxin and urinary d-arabinitol/l-arabinitol ratio. In all, 13 cases with proven or probable invasive fungal disease (IFD) were identified. The sensitivity of BG and GM at the time of diagnosis (TOD) was low, but within 2 weeks from the TOD the sensitivity of BG was 92%. BG >800 pg/mL was highly specific for IFD. At a pre-test probability of 12%, both BG and GM had negative predictive values (NPV) >0.9 but low positive predictive values (PPV). In a subgroup analysis of patients with clinically suspected IFD (pre-test probability of 35%), the NPV was lower, but the PPV for BG was 0.86 at cut-off 160 pg/mL. Among IFD patients, 91% had patterns of consecutively positive and increasing BG levels. Bis-methyl-gliotoxin was undetectable in 15 patients with proven, probable and possible IA. To conclude, BG was the superior fungal marker for IFD diagnosis. Quantification above the limit of detection and graphical evaluation of the pattern of dynamics are warranted in the interpretation of BG results.

Designing for Improved Patient Experiences in Home Dialysis: Usability and User Experience Findings From User-Based Evaluation Study With Patients With Chronic Conditions.

BACKGROUND: Chronic kidney disease affects 10% of the population worldwide, and the number of patients receiving treatment for end-stage kidney disease is forecasted to increase. Therefore, there is a pressing need for innovative digital solutions that increase the efficiency of care and improve patients' quality of life. The aim of the eHealth in Home Dialysis project is to create a novel eHealth solution, called eC4Me, to facilitate predialysis and home dialysis care for patients with chronic kidney disease. OBJECTIVE: Our study aimed to evaluate the usability, user experience (UX), and patient experience (PX) of the first version of the eC4Me solution. METHODS: We used a user-based evaluation approach involving usability testing, questionnaire, and interview methods. The test sessions were conducted remotely with 10 patients with chronic kidney disease, 5 of whom had used the solution in their home environment before the tests, while the rest were using it for the first time. Thematic analysis was used to analyze user test and questionnaire data, and descriptive statistics were calculated for the UMUX (Usability Metric for User Experience) scores. RESULTS: Most usability problems were related to navigation, the use of terminology, and the presentation of health-related data. Despite usability challenges, UMUX ratings of the solution were positive overall. The results showed noteworthy variation in the expected benefits and perceived effort of using the solution. From a PX perspective, it is important that the solution supports patients' own health-related goals and fits with the needs of their everyday lives with the disease. CONCLUSIONS: A user-based evaluation is a useful and necessary part of the eHealth solution development process. Our study findings can be used to improve the usability and UX of the evaluated eC4Me solution. Patients should be actively involved in the solution development process when specifying what information is relevant for them. Traditional usability tests complemented with questionnaire and interview methods can serve as a meaningful methodological approach for gaining insight not only into usability but also into UX- and PX-related aspects of digital health solutions.

Influenza-associated invasive aspergillosis in patients admitted to the intensive care unit in Sweden: a prospective multicentre cohort study.

BACKGROUND: The purpose of this study was to prospectively investigate the incidence of influenza-associated pulmonary aspergillosis (IAPA) in influenza patients admitted to intensive care units in Sweden. METHODS: The study included consecutive adult patients with PCR-verified influenza A or B in 12 Swedish intensive care units (ICUs) over four influenza seasons (2019-2023). Patients were screened using serum galactomannan and ß-d-glucan tests and fungal culture of a respiratory sample at inclusion and weekly during the ICU stay. Bronchoalveolar lavage was performed if clinically feasible. IAPA was classified according to recently proposed case definitions. RESULTS: The cohort included 55 patients; 42% were female, and the median age was 59 (IQR 48-71) years. All patients had at least one galactomannan test, ß-d-glucan test and respiratory culture performed. Bronchoalveolar lavage was performed in 24 (44%) of the patients. Five (9%, 95% CI 3.8% - 20.4%) patients were classified as probable IAPA, of which four lacked classical risk factors. The overall ICU mortality was significantly higher among IAPA patients than non-IAPA patients (60% vs 8%, p = 0.01). CONCLUSIONS: The study represents the first prospective investigation of IAPA incidence. The 9% incidence of IAPA confirms the increased risk of invasive pulmonary aspergillosis among influenza patients admitted to the ICU. Therefore, it appears reasonable to implement a screening protocol for the early diagnosis and treatment of IAPA in influenza patients receiving intensive care. TRIAL REGISTRATION: ClinicalTrials.gov NCT04172610, registered November 21, 2019.

Fungal Tracheobronchitis in Lung Transplant Recipients: Incidence and Utility of Diagnostic Markers.

Fungal tracheobronchitis caused by Aspergillus and Candida spp. is a recognized complication after lung transplantation, but knowledge of the incidence of Candida tracheobronchitis is lacking. The diagnosis relies on fungal cultures in bronchoalveolar lavage fluid (BALF), but cultures have low specificity. We aimed to evaluate the one-year incidence of fungal tracheobronchitis after lung transplantation and to assess the utility of diagnostic markers in serum and BALF to discriminate fungal tracheobronchitis from colonization. Ninety-seven consecutively included adult lung-transplant recipients were prospectively followed. BALF and serum samples were collected at 1, 3 and 12 months after transplantation and analyzed for betaglucan (serum and BALF), neutrophils (BALF) and galactomannan (BALF). Fungal tracheobronchitis was defined according to consensus criteria, modified to include Candida as a mycologic criterion. The cumulative one-year incidence of Candida and Aspergillus tracheobronchitis was 23% and 16%, respectively. Neutrophils of >75% of total leukocytes in BALF had 92% specificity for Candida tracheobronchitis. The area under the ROC curves for betaglucan and galactomannan in BALF to discriminate Aspergillus tracheobronchitis from colonization or no fungal infection were high (0.86 (p < 0.0001) and 0.93 (p < 0.0001), respectively). To conclude, the one-year incidence of fungal tracheobronchitis after lung transplantation was high and dominated by Candida spp. Diagnostic markers in BALF could be useful to discriminate fungal colonization from tracheobronchitis.