Clinical characteristics of Pseudomonas and Aspergillus co-infected cystic fibrosis patients: A UK registry study.

BACKGROUND: Pseudomonas aeruginosa (Pa) and Aspergillus species (Asp) are the most common bacterial and fungal organisms respectively in CF airways. Our aim was to examine impacts of Asp infection and Pa/Asp co-infection. METHODS: Patients on the UK CF Registry in 2016 were grouped into: absent (Pa-), intermittent (Pai) or chronic Pa (Pac), each with Asp positive (Asp+) or negative (Asp-). Primary outcome was best percentage predicted FEV1 (ppFEV1) that year. Secondary outcomes were intravenous (IV) antibiotic courses, growth (height, weight, BMI) and additional disease complications. Associations between outcomes and infection-status were assessed using regression models adjusting for significant confounders (age, sex, Phe508del homozygosity and CF-related diabetes (CFRD)). RESULTS: 9,270 patients were included (median age 19 [IQR 9-30] years, 54% male, 50% Phe508del/F508del). 4,142 patients (45%) isolated Pa, 1,460 (16%) Asp. Pa-/Asp+ subjects had an adjusted ppFEV1 that was 5.9% lower than Pa-/Asp- (p < 0.0001). In patients with Pai or Pac, there was no additional impact of Asp on ppFEV1. However, there was a higher probability that Pac/Asp+ patients had required IV antibiotics than Pac/Asp- group (OR 1.23 [1.03-1.48]). Low BMI, ABPA, CF-liver disease and CFRD were all more frequent with Asp alone than Pa-/Asp-, though not more common in Pac/Asp+ than Pac/Asp-. CONCLUSIONS: Co-infection with Pa and Asp was not associated with reduced lung function compared with Pa alone, but was associated with additional use of IV antibiotics. Asp infection itself is associated with several important indicators of disease severity. Longitudinal analyses should explore the impact of co-infection on disease progression.

Aspergillus fumigatus tryptophan metabolic route differently affects host immunity.

Indoleamine 2,3-dioxygenases (IDOs) degrade l-tryptophan to kynurenines and drive the de novo synthesis of nicotinamide adenine dinucleotide. Unsurprisingly, various invertebrates, vertebrates, and even fungi produce IDO. In mammals, IDO1 also serves as a homeostatic regulator, modulating immune response to infection via local tryptophan deprivation, active catabolite production, and non-enzymatic cell signaling. Whether fungal Idos have pleiotropic functions that impact on host-fungal physiology is unclear. Here, we show that Aspergillus fumigatus possesses three ido genes that are expressed under conditions of hypoxia or tryptophan abundance. Loss of these genes results in increased fungal pathogenicity and inflammation in a mouse model of aspergillosis, driven by an alternative tryptophan degradation pathway to indole derivatives and the host aryl hydrocarbon receptor. Fungal tryptophan metabolic pathways thus cooperate with the host xenobiotic response to shape host-microbe interactions in local tissue microenvironments.

Invasive fungal disease misdiagnosed as tumour in association with orbital apex syndrome.

Invasive sino-orbital aspergillosis is a rare cause of orbital apex syndrome (OAS) in immunocompetent patients and often misdiagnosed as tumour because of its aggressive nature and invasive patterns. We report a 23-year-old immunocompetent man presenting with painful progressive loss of vision, ophthalmoplegia and proptosis of the right eye suggestive of OAS. MRI with gadolinium contrast showed an enhancing heterogeneous mass filling the paranasal sinuses, extraconal space and extending up to the right orbital apex. A functional endoscopic biopsy reported as invasive sino-orbital aspergillosis. He was started on intravenous voriconazole and maximal surgical debridement was done. He gradually regained his vision to 20/30 in the right eye. A review of literature reported several such cases which were managed medically or surgically but with poor visual recovery. This case highlights the need for awareness among clinicians for early diagnosis and treatment to prevent vision loss and better survival.

Risk factors for respiratory Aspergillus fumigatus in German Cystic Fibrosis patients and impact on lung function.

Airway inflammation and chronic lung infections in cystic fibrosis (CF) patients are mostly caused by bacteria, e.g. Pseudomonas aeruginosa (PA). The role of fungi in the CF lung is still not well elucidated, but evidence for a harmful and complex role is getting stronger. The most common filamentous fungus in CF is Aspergillus fumigatus (AF). Age and continuous antibiotic treatment have been discussed as risk factors for AF colonisation but did not differentiate between transient and persistent AF colonisation. Also, the impact of co-colonisation of PA and AF on lung function is still under investigation. Data from patients with CF registered in the German Cystic Fibrosis Registry database in 2016 and 2017 were retrospectively analysed, involving descriptive and multivariate analysis to assess risk factors for transient or persistent AF colonisation. Age represented an independent risk factor for persistent AF colonisation. Prevalence was low in children less than ten years, highest in the middle age and getting lower in higher age (≥ 50 years). Continuous antibiotic lung treatment was significantly associated with AF prevalence in all age groups. CF patients with chronic PA infection had a lower lung function (FEV1%predicted), which was not influenced by an additional AF colonisation. AF colonisation without chronic PA infection, however, was significantly associated with a lower function, too. Older age up to 49 years and continuous antibiotic use were found to be the main risk factors for AF permanent colonisation. AF might be associated with decrease of lung function if not disguised by chronic PA infection.

Galectin-3 enhances neutrophil motility and extravasation into the airways during Aspergillus fumigatus infection.

Aspergillus fumigatus is an opportunistic mold that infects patients who are immunocompromised or have chronic lung disease, causing significant morbidity and mortality in these populations. While the factors governing the host response to A. fumigatus remain poorly defined, neutrophil recruitment to the site of infection is critical to clear the fungus. Galectin-3 is a mammalian ß-galactose-binding lectin with both antimicrobial and immunomodulatory activities, however the role of galectin-3 in the defense against molds has not been studied. Here we show that galectin-3 expression is markedly up-regulated in mice and humans with pulmonary aspergillosis. Galectin-3 deficient mice displayed increased fungal burden and higher mortality during pulmonary infection. In contrast to previous reports with pathogenic yeast, galectin-3 exhibited no antifungal activity against A. fumigatus in vitro. Galectin-3 deficient mice exhibited fewer neutrophils in their airways during infection, despite normal numbers of total lung neutrophils. Intravital imaging studies confirmed that galectin-3 was required for normal neutrophil migration to the airspaces during fungal infection. Adoptive transfer experiments demonstrated that stromal rather than neutrophil-intrinsic galectin-3 was necessary for normal neutrophil entry into the airspaces. Live cell imaging studies revealed that extracellular galectin-3 directly increases neutrophil motility. Taken together, these data demonstrate that extracellular galectin-3 facilitates recruitment of neutrophils to the site of A. fumigatus infection, and reveals a novel role for galectin-3 in host defense against fungal infections.

Case Report: Beyond the Blood-retina Barrier: Intravitreal Caspofungin for Fungal Endophthalmitis.

SIGNIFICANCE: Two fungal endophthalmitis cases demonstrate safety and efficiency of intravitreal caspofungin as a new therapy option in fungal endophthalmitis. PURPOSE: The purpose of this study was to evaluate the intravitreal application of caspofungin for the treatment of fungal endophthalmitis because rising resistance to voriconazole and amphotericin B leads to a need for new antifungal therapy options. CASE REPORT: Initially, both patients with fungal endophthalmitis underwent pars plana vitrectomy. Microbiological analysis revealed Aspergillus terreus and Candida dubliniensis, which both possess atypical resistance patterns. Caspofungin has a low bioavailability in the eye when given systemically. It was injected intravitreally into the eyes affected by fungal endophthalmitis. An injection of 100 µg of caspofungin in a volume 0.1 mL was applied repeatedly. Clinical parameters were recorded. Both eyes were stabilized by the treatment. Finally, the intraocular infections with atypical mycotic agents were eliminated. Visual acuity improved to 0.4 logMAR (20/50 Snellen) in the first case and to 1.0 logMAR (20/200 Snellen) in the second case. During the treatment course, we have not seen any toxic effects or damage of intraocular structures related to the intravitreal administration of caspofungin. CONCLUSIONS: In summary, intravitreal caspofungin was effective and well tolerated in both cases. Therefore, caspofungin seems to be a safe and effective intravitreal alternative to voriconazole and amphotericin B in fungal endophthalmitis.

Potential benefit of combination antifungal therapy in Aspergillus endocarditis.

Aspergillus endocarditis (AE) is a rare condition with a mortality rate greater than 60%. While it is generally accepted that both antifungal therapy and surgery are necessary for survival, the optimal antifungal regimen is unclear. A 62-year-old man was diagnosed with AE of a prosthetic aortic valve, complicated by cerebral emboli. He underwent debridement of the aortic valve abscess and valve replacement, and was managed with a combination of liposomal amphotericin B and voriconazole for 7 weeks followed by long-term suppressive azole therapy. He remained well at follow-up 18 months later. Data from a review of case reports published between 1950 and 2010 revealed greater survival rates in patients managed with two or more antifungals as opposed to single agent therapy. We provide an updated literature review with similar findings, suggesting that dual agent antifungal therapy should be considered in patients with AE.

Chronic invasive fungal rhinosinusitis vs sinonasal squamous cell carcinoma: the differentiating value of MRI.

OBJECTIVES: To investigate MRI features in discriminating chronic invasive fungal rhinosinusitis (CIFRS) from sinonasal squamous cell carcinomas (SNSCC). METHODS: MRI findings of 33 patients with CIFRS and 47 patients with SNSCC were retrospectively reviewed and compared. Multivariate logistic regression analysis was performed to identify significant imaging features in distinguishing between CIFRS and SNSCC. The ROC curves and the AUC were used to evaluate diagnostic performance. RESULTS: There were significant differences in cavernous sinus involvement (p < 0.001), sphenoid sinus involvement (p < 0.001), meningeal involvement (p = 0.024), T2 signal intensity (p = 0.006), and enhancement pattern (p < 0.001) between CIFRS and SNSCC. Multivariate logistic regression analysis identified cavernous sinus involvement (odds ratio [OR] = 0.06, 95% confidence interval [95% CI] = 0.02-0.20) and sphenoid sinus involvement (OR = 0.14, 95% CI = 0.05-0.45) as significant indicators for CIFRS and T2 isointensity to gray matter (OR = 4.44, 95% CI = 1.22-16.22) was a significant indicator for SNSCC. ROC curve analysis showed the AUC from a combination of three imaging features was 0.95 in differentiating CIFRS and SNSCC. CONCLUSIONS: MRI showed significant differences between CIFRS and SNSCC features. In immunocompromised patients, a sinonasal hypointense mass on T2WI with septal enhancement or loss of contrast enhancement, and involvement of cavernous sinus, sphenoid sinus, and meninges strongly suggest CIFRS. KEY POINTS: • Chronic invasive fungal rhinosinusitis (CIFRS) is often difficult to distinguish from sinonasal squamous cell carcinomas (SNSCC) in clinical practice. • Cavernous sinus and sphenoid sinus involvement appear to be significant indicators for CIFRS. T2 isointensity to gray matter appears to be a significant indicator for SNSCC. • Loss of contrast enhancement and septal enhancement can be used to distinguish CIFRS from SNSCC with a high degree of specificity.

Molecular epidemiology of Aspergillus species and other moulds in respiratory samples from Argentinean patients with cystic fibrosis.

In cystic fibrosis (CF) patients, fungal colonization of the respiratory tract is frequently found. Aspergillus fumigatus is the most frequently recorded and is associated with loss of pulmonary function and allergic disease (ABPA). The knowledge on prevalence rates of filamentous fungi in CF patients in Latin America is scarce. One hundred and seventy-six fungal isolates recovered from the upper respiratory tract of CF patients from Argentina were identified to species by morphology and DNA sequencing. In total, 90% of CF patients were colonized by Aspergillus sp., followed by Exophiala sp. (14%) and Scedosporium sp. (10%). Among Aspergillus, six species complexes (Fumigati, Flavi, Terrei, Nigri, Usti, and Nidulante) and different cryptospecies were found. Among Scedosporium, three species were observed (Scedosporium apiospermum, Scedosporium aurantiacum and Scedosporium boydii). All Exophiala isolates were identified as Exophiala dermatitidis. Rare filamentous fungi were also found. All cases of ABPA were associated to the presence of A. fumigatus. Mixed colonization with other mould or rare fungi was observed in half of them. To our knowledge, this is the first prospective study of mould species in CF using molecular methods in Latin America. This study shows that Aspergillus sp., E. dermatitidis and Scedosporium sp. have a high frequency in CF patients from Argentina, and by far, A. fumigatus was the most commonly cultured species. Continuous clinical surveillance is required to detect the emergence of new fungal pathogens and to detect resistant or difficult-to-treat species capable of chronic colonizing the airways and of hematogenous dissemination in case of lung transplantation.

The role of pars plana vitrectomy in the management of fungal endogenous endophthalmitis.

PURPOSE: To identify the causative microorganism of fungal endogenous endophthalmitis in our tertiary referral uveitis center and review the therapeutic role of pars plana vitrectomy in patients with fungal endogenous endophthalmitis. METHODS: Seven eyes of six cases were identified as fungal endogenous endophthalmitis through positive cultures of ocular fluids and clinical presentations. The final anatomical and functional results were evaluated. RESULTS: Four women (66.7%) and two men (33.3%) underwent vitrectomy. Control of infection was achieved early on in all cases. Candida (71.4%) and Aspergillus (28.6%) species were identified as causative fungi in patients with fungal endogenous endophthalmitis. Two patients were reoperated due to reinfection and retinal detachment, respectively. Visual acuity improved in six eyes (85.7%) and worsened in one eye (14.3%). At the final examination, the retina was flat in all cases. No eye developed phthisis bulbi. CONCLUSION: Candida species are the most common causative organisms of fungal endogenous endophthalmitis in this study. Pars plana vitrectomy in fungal endogenous endophthalmitis may enhance the treatment of infection by removing fungal elements in the vitreous and aid in diagnosis. Vitrectomy may also be an important tool in the management of vision-threatening post-infectious sequelae such as retinal detachment and reinfections.

The role of Aspergillus fumigatus polysaccharides in host-pathogen interactions.

Aspergillus fumigatus is a saprophytic mold that can cause infection in patients with impaired immunity or chronic lung diseases. The polysaccharide-rich cell wall of this fungus is a key point of contact with the host immune system. The availability of purified cell wall polysaccharides and mutant strains deficient in the production of these glycans has revealed that these glycans play an important role in the pathogenesis of A. fumigatus infections. Herein, we review our current understanding of the key polysaccharides present within the A. fumigatus cell wall, and their interactions with host cells and secreted factors during infection.

Labeled quantitative mass spectrometry to study the host response during aspergillosis in the common bottlenose dolphin (Tursiops truncatus).

Aspergillosis is a fungal infection caused by Aspergillus molds that can affect both humans and animals. Despite advances in diagnostics and therapy, medical management of this disease remains difficult. Expansion of the basic knowledge regarding its pathophysiology in animals is critical to aid in the identification of new biomarkers of infection for diagnosis and therapeutic targets. For such a purpose, proteomics can be used by addressing protein changes during various disease processes. In the present study, a mass spectrometry analysis based on isobaric tagging for relative and absolute quantitation (iTRAQ®) was applied for direct identification and relative quantitation of proteins in blood collected from 32 Aspergillus-diseased common bottlenose dolphins (Tursiops truncatus, 32 samples) in comparison with blood from 55 other dolphins (55 samples from 41 clinically-normal controls and from 14 cetaceans with miscellaneous non-Aspergillus inflammation diseases) and ten convalescent dolphins (28 samples). Sixty-six and 40 proteins were found to be ≥2.0-fold over- and underrepresented versus miscellaneous non-Aspergillus inflammatory dolphins, respectively, and most were confirmed vs. clinically-normal controls and convalescents. Many proteins which play a role in the adaptive immune response were identified, including MHC proteins and others involved in catalytic activity like the NADPH-ubiquinone oxido-reductases. Overall, iTRAQ® appears to be a convenient proteomic tool greatly suited for exploratory ex vivo studies focusing on pathophysiology. This technique should be considered as a preliminary step before validation of new diagnostic markers.

Change in lung clearance index with microbiological status in children with cystic fibrosis.

The impact of infections caused by bacteria, especially Gram-negative, on the progression of lung disease in cystic fibrosis is well established. Decline in pulmonary function commence already at early age. In this group of patients, the lung clearance index seems to be a better marker than FEV1 allowing non-invasive monitoring of changes in small airways. The aim of this study was to investigate the association between the microbiological status and LCI derived from multiple breath washout (MBW) technique as well as FEV1 and FVC in children suffering from cystic fibrosis. Over the 1-year recruitment period, 136 CF patients aged 5-18 with: Staphylococcus aureus (n-27), Pseudomonas aeruginosa (first time (n-27), intermittent (n-9), and chronic (34) infection), Aspergillus fumigatus (n-6) and without pathogenic flora (n-33) were included in the study. Patients had performed a spirometry and MBW test during the visit at outpatient clinic. The study showed that the lung clearance index in patients infected with Aspergillus fumigatus was significantly higher (P < 0.05) than in those with normal throat flora. There was also statistically significant differences in the lung clearance index obtained in subjects with chronic Pseudomonas aeruginosa infection and those with first Pseudomonas aeruginosa infection (P < 0.05). Furthermore, significant statistical differences (P < 0.05) were observed between the groups of patients with chronic Pseudomonas aeruginosa infection FEV1 > 70% and FEV1 < 70%. In conclusion, LCI was associated with microbiological status of CF patients. Chronic lung infections, especially Aspergillus fumigatus and Pseudomonas aeruginosa, were associated with increased LCI. Early eradication of pathological flora positively affects the maintenance of lower LCI.

Fungal osteomyelitis in a patient with chronic granulomatous disease: Case report and review of the literature.

Chronic granulomatous disease (CGD) is the most common of the primary immunodeficiency in children. It is caused by single gene defect resulting in dysfunctional nicotinamide adenine dineucleotide phosphate (NADPH) oxidase complex causing recurrent bacterial and fungal infections. Here we present the case of a 9 year old boy who was a known case of CGD since three years of age. He presented with recent history of fever, left sided pain in the scapular region and difficulty in breathing. Chest imaging revealed developing left upper lobe consolidation and erosion of the 3rd posterior rib. The child underwent video assisted thoracoscopic surgery (VATS) and biopsy of the lesion. Histopathology revealed fungal hyphae which were confirmed to be Aspergillus nidulans on staining. He was successfully treated with voriconazole therapy. We will also review the literature on fungal osteomyelitis in CGD patients.

Gliotoxin penetrates and impairs the integrity of the human blood-brain barrier in vitro.

Cerebral fungal infections represent an important public health concern, where a key element of pathophysiology is the ability of the fungi to cross the blood-brain barrier (BBB). Yet the mechanism used by micro-organisms to cross such a barrier and invade the brain parenchyma remains unclear. This study investigated the effects of gliotoxin (GTX), a mycotoxin secreted by Aspergillus fumigatus, on the BBB using brain microvascular endothelial cells (BMECs) derived from induced pluripotent stem cells (iPSCs). We observed that both acute (2 h) and prolonged (24 h) exposure to GTX at the level of 1 µM or higher compromised BMECs monolayer integrity. Notably, acute exposure was sufficient to disrupt the barrier function in iPSC-derived BMECs, resulting in decreased transendothelial electrical resistance (TEER) and increased fluorescein permeability. Further, our data suggest that such disruption occurred without affecting tight junction complexes, via alteration of cell-matrix interactions, alterations in F-actin distribution, through a protein kinase C-independent signaling. In addition to its effect on the barrier function, we have observed a low permeability of GTX across the BBB. This fact can be partially explained by possible interactions of GTX with membrane proteins. Taken together, this study suggests that GTX may contribute in cerebral invasion processes of Aspergillus fumigatus by altering the blood-brain barrier integrity without disrupting tight junction complexes.

Plasma protein electrophoresis as a prognostic indicator in Aspergillus species-infected Gentoo penguins (Pygoscelis papua papua).

BACKGROUND: Avian aspergillosis presents a significant threat to captive penguin populations. Currently, a lack of objective prognostic factors limits disease staging, objective reassessment throughout treatment, comparative evaluation of treatment regimes, and appropriate timing of euthanasia. OBJECTIVE: The study objective was to investigate absolute and relative plasma protein fractions by agarose gel electrophoresis (EPH) as predictors of survival in Gentoo penguins (Pygoscelis papua papua) under treatment for aspergillosis. METHODS: One hundred and eighty-three EPH profiles from individual clinical cases were examined retrospectively. Animal survival to 90 days post sampling was established from clinical records; birds either survived (n = 146) or died within 90 days (n = 37), and time to death was recorded. RESULTS: Fourteen variables showed statistically significant differences (P < .05) between surviving and dying birds. Receiver operating characteristic curve analysis identified total albumin concentration (albumin + prealbumin) and albumin-to-globulin (A:G) ratio as having strongest discriminatory values (95% CI) at 0.788 (0.710-0.866) and 0.784 (0.696-0.871), respectively. Albumin (concentration and percentage of total protein) displayed moderate discriminatory value but additionally a weak positive correlation with time to death (95% CI); r = .353 (0.033-0.608) and .424 (0.116-0.658), respectively. CONCLUSIONS: Optimized test cutoffs for total albumins, albumin (concentration and percentage of total protein), and A:G ratio achieved moderate sensitivity and specificity, strong negative predictive values, but weak positive predictive values due to a low prevalence of death. Selection of appropriate test cutoff values may provide valuable adjunctive prognostic tools for clinical decision-making when the prognosis is difficult to assess clinically.

The microbiome-metabolome crosstalk in the pathogenesis of respiratory fungal diseases.

Filamentous fungi of the genus Aspergillus are responsible for several superficial and invasive infections and allergic syndromes. The risk of infection and its clinical outcome vary significantly even among patients with similar predisposing clinical factors and pathogen exposure. There is increasing evidence that the individual microbiome supervises the outcome of the host-fungus interaction by influencing mechanisms of immune regulation, inflammation, metabolism, and other physiological processes. Microbiome-mediated mechanisms of resistance allow therefore the control of fungal colonization, preventing the onset of overt disease, particularly in patients with underlying immune dysfunction. Here, we review this emerging area of research and discuss the contribution of the microbiota (and its dysbiosis), including its immunoregulatory properties and relationship with the metabolic activity of commensals, to respiratory fungal diseases. Finally, we highlight possible strategies aimed at decoding the microbiome-metabolome dialog and at its exploitation toward personalized medical interventions in patients at high risk of infection.