COVID-19-associated pulmonary aspergillosis in mechanically ventilated patients: a prospective, multicentre UK study.

BACKGROUND: Invasive pulmonary aspergillosis is a complication of severe COVID-19, with regional variation in reported incidence and mortality. We describe the incidence, risk factors and mortality associated with COVID-19-associated pulmonary aspergillosis (CAPA) in a prospective, multicentre UK cohort. METHODS: From March 2020 to March 2021, 266 mechanically ventilated adults with COVID-19 were enrolled across 5 UK hospital intensive care units (ICUs). CAPA was defined using European Confederation for Medical Mycology and the International Society for Human and Animal Mycology criteria and fungal diagnostics performed on respiratory and serum samples. RESULTS: Twenty-nine of 266 patients (10.9%) had probable CAPA, 14 (5.2%) possible CAPA and none proven CAPA. Probable CAPA was diagnosed a median of 9 (IQR 7-16) days after ICU admission. Factors associated with probable CAPA after multivariable logistic regression were cumulative steroid dose given within 28 days prior to ICU admission (adjusted OR (aOR) 1.16; 95% CI 1.01 to 1.43 per 100 mg prednisolone-equivalent), receipt of an interleukin (IL)-6 inhibitor (aOR 2.79; 95% CI 1.22 to 6.48) and chronic obstructive pulmonary disease (COPD) (aOR 4.78; 95% CI 1.13 to 18.13). Mortality in patients with probable CAPA was 55%, vs 46% in those without. After adjustment for immortal time bias, CAPA was associated with an increased risk of 90-day mortality (HR 1.85; 95% CI 1.07 to 3.19); however, this association did not remain statistically significant after further adjustment for confounders (adjusted HR 1.57; 95% CI 0.88 to 2.80). There was no difference in mortality between patients with CAPA prescribed antifungals (9 of 17; 53%) and those who were not (7 of 12; 58%) (p=0.77). INTERPRETATION: In this first prospective UK study, probable CAPA was associated with corticosteroid use, receipt of IL-6 inhibitors and pre-existing COPD. CAPA did not impact mortality following adjustment for prognostic variables.

Bronchiectasis severity correlates with outcome in patients with primary antibody deficiency.

Bronchiectasis is a well-recognised complication of primary antibody deficiency (PAD) syndromes. Previous data suggest that mortality in common variable immune deficiency (CVID) is not associated with isolated bronchiectasis. A retrospective analysis of patients with CVID and specific antibody deficiency in two tertiary referral centres with lung disease was conducted. Severity of bronchiectasis at presentation was associated with mortality. Lower FEV1, colonisation with Pseudomonas aeruginosa and a diagnosis of COPD were also associated with mortality. Bronchiectasis is an important driver of mortality in patients with PAD syndromes.

Screening for Candida auris in patients admitted to eight intensive care units in England, 2017 to 2018.

BackgroundCandida auris is an emerging multidrug-resistant fungal pathogen associated with bloodstream, wound and other infections, especially in critically ill patients. C. auris carriage is persistent and is difficult to eradicate from the hospital environment.AimWe aimed to pilot admission screening for C. auris in intensive care units (ICUs) in England to estimate prevalence in the ICU population and to inform public health guidance.MethodsBetween May 2017 and April 2018, we screened admissions to eight adult ICUs in hospitals with no previous cases of C. auris, in three major cities. Swabs were taken from the nose, throat, axilla, groin, perineum, rectum and catheter urine, then cultured and identified using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS). Patient records were linked to routine ICU data to describe and compare the demographic and health indicators of the screened cohort with a national cohort of ICU patients admitted between 2016 and 2017.ResultsAll C. auris screens for 921 adults from 998 admissions were negative. The upper confidence limit of the pooled prevalence across all sites was 0.4%. Comparison of the screened cohort with the national cohort showed it was broadly similar to the national cohort with respect to demographics and co-morbidities.ConclusionThese findings imply that C. auris colonisation among patients admitted to ICUs in England is currently rare. We would not currently recommend widespread screening for C. auris in ICUs in England. Hospitals should continue to screen high-risk individuals based on local risk assessment.

Comparative Evaluation of MIRONAUT-AM and CLSI broth microdilution method for antifungal susceptibility testing of Aspergillus species against four commonly used antifungals.

The aim of this study was to evaluate a colorimetric method, MIRONAUT-AM, for determining susceptibility testing of anidulafungin, amphotericin, voriconazole, and itraconazole by comparing the minimum inhibitory (effective) concentrations (MICs/MECs) obtained by this method to those generated by the reference Clinical Laboratory Standard Institute (CLSI) broth microdilution method. In sum, 78 clinical isolates of Aspergillus species, nine of them non-wild type (non-WT) with itraconazole MIC ranging from 2 mg/l to >16 mg/l, were tested against above antifungals. A. fumigatus ATCC 204305 was used as a reference strain, and test was performed in accordance with slightly modified yeast susceptibility testing instruction of the manufacture; conidia suspension inoculum and alamarBlue concentration were optimized. These same isolates were referred to Bristol Mycology reference laboratory and tested by CLSI method. The MICs and MECs generated by the two methods were compared using concordance analysis. MIRONAUT-AM showed significant concordance (P < .0001) with CLSI method, and overall agreement was high (≥90%). In addition, MIRONAUT-AM produced echinocandin MECs results within 18-24 hours incubation time and correctly detected all non-WT isolates except one isolate. This colorimetric method is very promising and appears to be a suitable alternative susceptibility testing method to labor intensive broth microdilution reference method for Aspergillus species.

Candida auris: a Review of the Literature.

The emerging pathogen Candida auris has been associated with nosocomial outbreaks on five continents. Genetic analysis indicates the simultaneous emergence of separate clades of this organism in different geographical locations. Invasive infection and colonization have been detected predominantly in patients in high-dependency settings and have garnered attention due to variable antifungal resistance profiles and transmission within units instituting a range of infection prevention and control measures. Issues with the identification of C. auris using both phenotypic and molecular techniques have raised concerns about detecting the true scale of the problem. This review considers the literature available on C. auris and highlights the key unknowns, which will provide direction for further work in this field.

Rapid and extensive karyotype diversification in haploid clinical Candida auris isolates.

Candida auris is a newly emerged pathogenic microbe, having been identified as a medically relevant fungus as recently as 2009. It is one of the most drug-resistant yeast species known to date and its emergence and population structure are unusual. Because of its recent emergence, we are largely ignorant about fundamental aspects of its general biology, life cycle, and population dynamics. Here, we report the karyotype variability of 26 C. auris strains representing the four main clades. We demonstrate that all strains are haploid and have a highly plastic karyotype containing five to seven chromosomes, which can undergo marked alterations within a short time frame when the fungus is put under genotoxic, heat, or osmotic stress. No simple correlation was found between karyotype pattern, drug resistance, and clade affiliation indicating that karyotype heterogeneity is rapidly evolving. As with other Candida species, these marked karyotype differences between isolates are likely to have an important impact on pathogenic traits of C. auris.

In vitro antifungal activity of a novel topical triazole PC945 against emerging yeast Candida auris.

OBJECTIVES: Management of Candida auris infection is difficult as this yeast exhibits resistance to different classes of antifungals, necessitating the development of new antifungals. The aim of this study was to investigate the susceptibility of C. auris to a novel antifungal triazole, PC945, optimized for topical delivery. METHODS: A collection of 50 clinical isolates was obtained from a tertiary care hospital in North India. Nine isolates from the UK, 10 from a CDC panel (USA) and 3 from the CBS-KNAW culture collection (Japanese and South Korean isolates) were also obtained. MICs (azole endpoint) of PC945 and other triazoles were determined in accordance with CLSI M27 (third edition). Quality control strains were included [Candida parapsilosis (ATCC 22019) and Candida krusei (ATCC 6258)]. RESULTS: Seventy-four percent of isolates tested showed reduced susceptibility to fluconazole (≥64 mg/L). PC945 (geometric mean MIC = 0.058 mg/L) was 7.4-fold and 1.5-fold more potent than voriconazole and posaconazole, respectively (both P < 0.01). PC945 MIC values correlated with those of voriconazole or posaconazole, and only three isolates were found to be cross-resistant between PC945 and other azoles. ERG11 sequence analysis revealed several mutations, but no correlation could be established with the MIC of PC945. Tentative epidemiological cut-off values (ECOFFs) evaluated by CLSI's ECOFF Finder (at 99%) with 24 h reading of MICs were 1, 4 and 1 mg/L for PC945, voriconazole and posaconazole, respectively. MIC values for quality control strains of all triazoles were in the normal ranges. CONCLUSIONS: PC945 was found to be a more potent inhibitor than posaconazole, voriconazole and fluconazole of C. auris isolates collected globally, warranting further laboratory and clinical evaluations.

ECMM CandiReg-A ready to use platform for outbreaks and epidemiological studies.

BACKGROUND: Recent outbreaks of Candida auris further exemplify that invasive Candida infections are a substantial threat to patients and healthcare systems. Even short treatment delays are associated with higher mortality rates. Epidemiological shifts towards more resistant Candida spp. require careful surveillance. OBJECTIVES: Triggered by the emergence of C auris and by increasing antifungal resistance rates the European Confederation of Medical Mycology developed an international Candida Registry (FungiScope™ CandiReg) to allow contemporary multinational surveillance. METHODS: CandiReg serves as platform for international cooperation to enhance research regarding invasive Candida infections. CandiReg uses the General Data Protection Regulation compliant data platform ClinicalSurveys.net that holds the electronic case report forms (eCRF). Data entry is supported via an interactive macro created by the software that can be accessed via any Internet browser. RESULTS: CandiReg provides an eCRF for invasive Candida infections that can be used for a variety of studies from cohort studies on attributable mortality to evaluations of guideline adherence, offering to the investigators of the 28 ECMM member countries the opportunity to document their cases of invasive Candida infection. CandiReg allows the monitoring of epidemiology of invasive Candida infections, including monitoring of multinational outbreaks. Here, we describe the structure and management of the CandiReg platform. CONCLUSION: CandiReg supports the collection of clinical information and isolates to improve the knowledge on epidemiology and eventually to improve management of invasive Candida infections. CandiReg promotes international collaboration, improving the availability and quality of evidence on invasive Candida infection and contributes to improved patient management.

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.

Airway persistence by the emerging multi-azole-resistant Rasamsonia argillacea complex in cystic fibrosis.

Infections caused by Rasamsonia argillacea complex have been reported in various clinical settings. Cystic fibrosis (CF) is one of the main underlying conditions. An observational cohort study of CF patients with Rasamsonia in respiratory samples was conducted. Eight isolates from 6 patients were identified as R. argillacea complex and tested for antifungal susceptibility. All isolates had high MICs to voriconazole and posaconazole and low MECs to echinocandins. Four patients experienced lung function decline in the year preceding first Rasamsonia isolation. This continued in the year following first isolation in 3 out of 4 cases. Antifungal therapy was initiated in 2 patients, to which only one exhibited a clinical response. Three out of 6 patients died within 3 years of isolating Rasamsonia. Genotyping suggests that similar genotypes of Rasamsonia can persist in CF airways. Consistent with other fungi in CF, the clinical impact of airway colonisation by Rasamsonia is variable. In certain patients, Rasamsonia may be able to drive clinical decline. In others, though a clear impact on lung function may be difficult to determine, the appearance of Rasamsonia acts as a marker of disease severity. In others it does not appear to have an obvious clinical impact on disease progression.

Insidious Risk of Severe Mycobacterium chimaera Infection in Cardiac Surgery Patients.

BACKGROUND: An urgent UK investigation was launched to assess risk of invasive Mycobacterium chimaera infection in cardiothoracic surgery and a possible association with cardiopulmonary bypass heater-cooler units following alerts in Switzerland and The Netherlands. METHODS: Parallel investigations were pursued: (1) identification of cardiopulmonary bypass-associated M. chimaera infection through national laboratory and hospital admissions data linkage; (2) cohort study to assess patient risk; (3) microbiological and aerobiological investigations of heater-coolers in situ and under controlled laboratory conditions; and (4) whole-genome sequencing of clinical and environmental isolates. RESULTS: Eighteen probable cases of cardiopulmonary bypass-associated M. chimaera infection were identified; all except one occurred in adults. Patients had undergone valve replacement in 11 hospitals between 2007 and 2015, a median of 19 months prior to onset (range, 3 months to 5 years). Risk to patients increased after 2010 from <0.2 to 1.65 per 10000 person-years in 2013, a 9-fold rise for infections within 2 years of surgery (rate ratio, 9.08 [95% CI, 1.81-87.76]). Endocarditis was the most common presentation (n = 11). To date, 9 patients have died. Investigations identified aerosol release through breaches in heater-cooler tanks. Mycobacterium chimaera and other pathogens were recovered from water and air samples. Phylogenetic analysis found close clustering of strains from probable cases. CONCLUSIONS: We identified low but escalating risk of severe M. chimaera infection associated with heater-coolers with cases in a quarter of cardiothoracic centers. Our investigations strengthen etiological evidence for the role of heater-coolers in transmission and raise the possibility of an ongoing, international point-source outbreak. Active management of heater-coolers and heightened clinical awareness are imperative given the consequences of infection.

In vitro efficacy of disinfectants utilised for skin decolonisation and environmental decontamination during a hospital outbreak with Candida auris.

Candida auris has caused nosocomial infections and transmissions within hospital settings. As little is known about the efficacy of skin and environmental decontamination products to kill C. auris, this study investigated the in vitro activity of chlorine, chlorhexidine, iodine povidone and vaporised hydrogen peroxide products against C. auris. H2 O2 vapour showed 96.6%-100% effective killing of C. auris. All isolates were inhibited by chlorhexidine gluconate concentrations at 0.125%-1.5% and for iodinated povidone at 0.07%-1.25%. Other species of Candida were also killed at 1000 ppm chlorine except C. parapsilosis which failed to be killed at 3 minutes contact time. We conclude that chlorhexidine gluconate, iodinated povidone, chlorine and H2 O2 vapour demonstrate effective killing activity against C. auris at concentrations used in clinical practice.

Serum opsonin ficolin-A enhances host-fungal interactions and modulates cytokine expression from human monocyte-derived macrophages and neutrophils following Aspergillus fumigatus challenge.

Invasive aspergillosis is a devastating invasive fungal disease associated with a high mortality rate in the immunocompromised, such as leukaemia patients, transplant patients and those with HIV/AIDS. The rodent serum orthologue of human L-ficolin, ficolin-A, can bind to and opsonize Aspergillus fumigatus, the pathogen that causes invasive aspergillosis, and may participate in fungal defence. Using human monocyte-derived macrophages and neutrophils isolated from healthy donors, we investigated conidial association and fungal viability by flow cytometry and microscopy. Additionally, cytokine production was measured via cytometric bead arrays. Ficolin-A opsonization was observed to significantly enhance association of conidia, while also inhibiting hyphal growth and contributing to increased fungal killing following incubation with monocyte-derived macrophages and neutrophils. Additionally, ficolin-A opsonization was capable of manifesting a decrease in IL-8, IL-1ß, IL-6, IL-10 and TNF-α production from MDM and IL-1ß, IL-6 and TNF-α from neutrophils 24 h post-infection. In conclusion, rodent ficolin-A is functionally comparable to human L-ficolin and is capable of modulating the innate immune response to A. fumigatus, down-regulating cytokine production and could play an important role in airway immunity.

The serum opsonin L-ficolin is detected in lungs of human transplant recipients following fungal infections and modulates inflammation and killing of Aspergillus fumigatus.

BACKGROUND: Invasive aspergillosis (IA) is a life-threatening systemic fungal infection in immunocompromised individuals that is caused by Aspergillus fumigatus. The human serum opsonin, L-ficolin, has been observed to recognize A. fumigatus and could participate in fungal defense. METHODS: Using lung epithelial cells, primary human monocyte-derived macrophages (MDMs), and neutrophils from healthy donors, we assessed phagocytosis and killing of L-ficolin-opsonized live A. fumigatus conidia by flow cytometry and microscopy. Additionally, cytokines were measured by cytometric bead array, and L-ficolin was measured in bronchoalveolar lavage (BAL) fluid from lung transplant recipients by enzyme-linked immunosorbent assay. RESULTS: L-ficolin opsonization increased conidial uptake and enhanced killing of A. fumigatus by MDMs and neutrophils. Opsonization was also shown to manifest an increase in interleukin 8 release from A549 lung epithelial cells but decreased interleukin 1ß, interleukin 6, interleukin 8, interleukin 10, and tumor necrosis factor α release from MDMs and neutrophils 24 hours after infection. The concentration of L-ficolin in BAL fluid from patients with fungal infection was significantly higher than that for control subjects (P = .00087), and receiving operating characteristic curve analysis highlighted the diagnostic potential of L-ficolin for lung infection (area under the curve, 0.842; P < .0001). CONCLUSIONS: L-ficolin modulates the immune response to A. fumigatus. Additionally, for the first time, L-ficolin has been demonstrated to be present in human lungs.

H-ficolin binds Aspergillus fumigatus leading to activation of the lectin complement pathway and modulation of lung epithelial immune responses.

Aspergillus fumigatus is an opportunistic fungal pathogen that typically infects the lungs of immunocompromised patients leading to a high mortality. H-Ficolin, an innate immune opsonin, is produced by type II alveolar epithelial cells and could participate in lung defences against infections. Here, we used the human type II alveolar epithelial cell line, A549, to determine the involvement of H-ficolin in fungal defence. Additionally, we investigated the presence of H-ficolin in bronchoalveolar lavage fluid from transplant patients during pneumonia. H-Ficolin exhibited demonstrable binding to A. fumigatus conidia via l-fucose, d-mannose and N-acetylglucosamine residues in a calcium- and pH-dependent manner. Moreover, recognition led to lectin complement pathway activation and enhanced fungal association with A549 cells. Following recognition, H-ficolin opsonization manifested an increase in interleukin-8 production from A549 cells, which involved activation of the intracellular signalling pathways mitogen-activated protein kinase MAPK kinase 1/2, p38 MAPK and c-Jun N-terminal kinase. Finally, H-ficolin concentrations were significantly higher in bronchoalveolar lavage fluid of patients with lung infections compared with control subjects (n = 16; P = 0·00726). Receiver operating characteristics curve analysis further highlighted the potential of H-ficolin as a diagnostic marker for lung infection (area under the curve = 0·77; P < 0·0001). Hence, H-ficolin participates in A. fumigatus defence through the activation of the lectin complement pathway, enhanced fungus-host interactions and modulated immune responses.

[68Ga]Ga-Schizokinen, a Potential Radiotracer for Selective Bacterial Infection Imaging.

Gallium-68-labeled siderophores as radiotracers have gained interest for the development of in situ infection-specific imaging diagnostics. Here, we report radiolabeling, in vitro screening, and in vivo pharmacokinetics (PK) of gallium-68-labeled schizokinen ([68Ga]Ga-SKN) as a new potential radiotracer for imaging bacterial infections. We radiolabeled SKN with ≥95% radiochemical purity. Our in vitro studies demonstrated its hydrophilic characteristics, neutral pH stability, and short-term stability in human serum and toward transchelation. In vitro uptake of [68Ga]Ga-SKN by Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and S. epidermidis, but no uptake by Candida glabrata, C. albicans, or Aspergillus fumigatus, demonstrated its specificity to bacterial species. Whole-body [68Ga]Ga-SKN positron emission tomography (PET) combined with computerized tomography (CT) in healthy mice showed rapid renal excretion with no or minimal organ uptake. The subsequent ex vivo biodistribution resembled this fast PK with rapid renal excretion with minimal blood retention and no major organ uptake and showed some dissociation of the tracer in the urine after 60 min postinjection. These findings warrant further evaluation of [68Ga]Ga-SKN as a bacteria-specific radiotracer for infection imaging.