COVID-19 Associated Pulmonary Aspergillosis in Patients on Extracorporeal Membrane Oxygenation Treatment-A Retrospective Study.

BACKGROUND: The incidence and outcome of pulmonary aspergillosis in coronavirus disease (COVID-19) patients on extracorporeal membrane oxygenation (ECMO) are unknown and have not been fully addressed. We investigated the incidence, risk factors and outcome of pulmonary aspergillosis in COVID-19 ECMO patients. In addition, the diagnostic utility of bronchoalveolar lavage fluid and CT scans in this setting were assessed. METHODS: We conducted a retrospective study on incidence and outcome of pulmonary aspergillosis in COVID-19 ECMO patients by reviewing clinical, radiological, and mycological evidence. These patients were admitted to a tertiary cardiothoracic centre during the early COVID-19 surge between March 2020 and January 2021. Results and measurements: The study included 88 predominantly male COVID-19 ECMO patients with a median age and a BMI of 48 years and 32 kg/m2, respectively. Pulmonary aspergillosis incidence was 10% and was associated with very high mortality. Patients with an Aspergillus infection were almost eight times more likely to die compared with those without infection in multivariate analysis (OR 7.81, 95% CI: 1.20-50.68). BALF GM correlated well with culture results, with a Kappa value of 0.8 (95% CI: 0.6, 1.0). However, serum galactomannan (GM) and serum (1-3)-ß-D-glucan (BDG) lacked sensitivity. Thoracic computed tomography (CT) diagnostic utility was also inconclusive, showing nonspecific ground glass opacities in almost all patients. CONCLUSIONS: In COVID-19 ECMO patients, pulmonary aspergillosis incidence was 10% and associated with very high mortality. Our results support the role of BALF in the diagnosis of pulmonary aspergillosis in COVID-19 ECMO patients. However, the diagnostic utility of BDG, serum GM, and CT scans is unclear.

Antifungal stewardship in solid-organ transplantation: What is needed?

BACKGROUND: Antifungal stewardship (AFS) lags behind antimicrobial stewardship (AMS) in terms of implementation, evidence base, and workforce experience. Solid-organ transplantation (SOT) carries a significant risk of invasive fungal infection, with high associated mortality, and is therefore associated with significant opportunities to optimize antifungal use. METHODS: A literature search for the terms "antifungal stewardship" and "solid-organ transplant" revealed a small evidence base to support AFS programs in this patient group. RESULTS: There is significant overlap in the methodology used in AMS and AFS programs, with notable differences in diagnostics, which are discussed in detail. The primary AFS interventions tested in SOT recipients are implementation of clinical guidelines and care bundles, digital enablers of AFS, and post-prescription review/audit and feedback. CONCLUSION: There is an urgent need for further research to support effective AFS strategies in this highly susceptible population.

Experience of Isavuconazole as a Salvage Therapy in Chronic Pulmonary Fungal Disease.

Background: Instances of resistant fungal infection are rising in pulmonary disease, with limited therapeutic options. Therapeutic drug monitoring of azole antifungals has been necessary to ensure safety and efficacy but is considered unnecessary for the newest triazole isavuconazole. Aims: To characterise the prevalence of isavuconazole resistance and use in a tertiary respiratory centre. Methods: A retrospective observational analysis (2016−2021) of adult respiratory patients analysing fungal culture, therapeutic drug monitoring, and outcome post-isavuconazole therapy. Results: During the study period, isavuconazole susceptibility testing was performed on 26 Aspergillus spp. isolates. A total of 80.8% of A. fumigatus isolates had isavuconazole (MIC > 1 mg/L, and 73.0% > 2 mg/L) with a good correlation to voriconazole MIC (r = 0.7, p = 0.0002). A total of 54 patients underwent isavuconazole therapy during the study period (median duration 234 days (IQR: 24−499)). A total of 67% of patients tolerated isavuconazole, despite prior azole toxicity in 61.8%, with increased age (rpb = 0.31; p = 0.021) and male sex (φc = 0.30; p = 0.027) being associated with toxicity. A total of 132 isavuconazole levels were performed with 94.8% > 1 mg/L and 72% > 2 mg/L. Dose change from manufacturer's recommendation was, however, required in 9.3% to achieve a concentration of >2 mg/L. Conclusion: We describe the use of isavuconazole as a salvage therapy in a chronic pulmonary fungal disease setting with a high prevalence of azole resistance. Therapeutic concentrations at standard dosing were high; however, results reinforce antifungal stewardship for optimization.

Utilisation of remote capillary blood testing in an outpatient clinic setting to improve shared decision making and patient and clinician experience: a validation and pilot study.

BACKGROUND: In a tertiary respiratory centre, large cohorts of patients are managed in an outpatient setting and require blood tests to monitor disease activity and organ toxicity. This requires either visits to tertiary centres for phlebotomy and physician review or utilisation of primary care services. OBJECTIVES: This study aims to validate remote capillary blood testing in an outpatient setting and analyse impact on clinical pathways. METHODS: A single-centre prospective cross-sectional validation and parallel observational study was performed. Remote finger prick capillary blood testing was validated compared with local standard venesection using comparative statistical analysis: paired t-test, correlation and Bland-Altman. Capillary was considered interchangeable with venous samples if all three criteria were met: non-significant paired t-test (ie, p>0.05), Pearson's correlation coefficient (r)>0.8% and 95% of tests within 10% difference through Bland-Altman (limits of agreement). In parallel, current clinical pathways including phlebotomy practice were analysed over 4 weeks to review test predictability. A subsequent pilot cohort study analysed potential impact of remote capillary blood sampling on shared decision making. A final implementation phase ensued to embed the service into clinical pathways within the institution. RESULTS: 117 paired capillary and venous blood samples were prospectively analysed. Interchangeability with venous blood was seen with glycated haemoglobin (%), total protein and C reactive protein. Further tests, although not interchangeable, are likely useful to enable longitudinal remote monitoring (eg, liver function and total IgE). 65% of outpatient clinic blood tests were predictable with 16% of patients requiring further follow-up. Patient and clinician-reported improvement in shared decision making given contemporaneous blood test results was observed. CONCLUSIONS: Remote capillary blood sampling can be used accurately for specific tests to monitor chronic disease, and when incorporated into an outpatient clinical pathway can improve shared decision making and patient experience. Further research is required to determine health economic impact and applicability within telemedicine-based outpatient care.

Experience of Ceftazidime/avibactam in a UK tertiary cardiopulmonary specialist center.

OBJECTIVES: Antimicrobial resistance is a major threat to public health. New drugs such as Ceftazidime/avibactam have been developed for the treatment of Multi-Drug resistant (MDR) pathogens. Susceptibility can be variable and inappropriate use can add a financial strain on the National Health Service (NHS). There is a pressing need to ensure these new and invaluable antimicrobials are preserved and used effectively. METHODS: We undertook a retrospective observational study to assess the use of Ceftazidime/avibactam and evaluated prescribing against applied standards. RESULTS: Between August 2017 and January 2019, 28 patients received 31 courses of Ceftazidime/avibactam. Prescribing according to the approved indications was observed for 68% of prescriptions (p < 0.0001). Duration of therapy was often prolonged but improved with Antimicrobial stewardship interventions. We observed 56% susceptibility (15/27 isolates) of MDR organisms (Pseudomonas, Klebsiella, Burkholderia, Enterobacter aerogenes, Achromobacter). We also report first in vivo experience to treat pulmonary disease caused by Non-tuberculous mycobacteria (NTM). Ceftazidime/avibactam was well tolerated, with no evidence of development of resistance at 6-months follow-up. CONCLUSIONS: Our study showed that Antimicrobial stewardship interventions led to a more appropriate use of Ceftazidime/avibactam (as measured by duration of therapy), preserving it as a treatment option for MDR infections.

A Prospective Real-World Study of the Impact of an Antifungal Stewardship Program in a Tertiary Respiratory-Medicine Setting.

There has been an increase in fungal infections in patients with chronic lung disease over the past decades, which is associated with rapidly increasing costs to health care systems. An antifungal stewardship team was introduced to a tertiary cardiopulmonary hospital, consisting of a medical mycologist and pharmacy support providing weekly stewardship ward rounds, twice-monthly multidisciplinary team meetings, and a dedicated weekly outpatient clinic. A database was set up to record the activity of the stewardship team. During the first 18 months of implementation, the antifungal stewardship team had reviewed 178 patients, with 285 recommendations made to inpatients, and 287 outpatient visits. The commonest diagnoses treated were allergic bronchopulmonary aspergillosis and chronic pulmonary aspergillosis. Cystic fibrosis was the largest patient group treated, followed by asthma and interstitial lung disease. There was a significant sustained reduction in monthly antifungal expenditure (P = 0.005) by £130,000 per month. There was also a significant reduction in antifungal use, measured as the defined daily dose/100 bed days (P = 0.017). There were no significant changes in expenditure on diagnostic tests. There has been a trend toward more patients having therapeutic levels of voriconazole (P = 0.086) and a significant increase in therapeutic levels of posaconazole (P < 0.0001). This study shows that an effective antifungal stewardship program can significantly reduce expenditure in a specialist respiratory service.