Publications by authors named "Agustin Resendiz Sharpe"

Background: Influenza-associated pulmonary aspergillosis (IAPA) is a severe fungal superinfection in critically ill influenza patients that is of incompletely understood pathogenesis. Despite the use of contemporary therapies with antifungal and antivirals, mortality rates remain unacceptably high. We aimed to unravel the IAPA immunopathogenesis as a means to develop adjunctive immunomodulatory therapies.

View Article and Find Full Text PDF

is an environmental yeast that primarily affects immunocompromised individuals, causing respiratory infections and life-threatening meningoencephalitis. Treatment is complicated by limited antifungal options, with concerns such as adverse effects, dose-limiting toxicity, blood-brain barrier permeability, and resistance development, emphasizing the critical need to optimize and expand current treatment options against invasive cryptococcosis. larvae have been introduced as an ethical intermediate for testing, bridging the gap between antifungal screening and mouse studies.

View Article and Find Full Text PDF
Article Synopsis
  • The management of invasive aspergillosis should be informed by antifungal susceptibility testing (AFST), with the disk diffusion (DD) method being a cost-effective and straightforward alternative to traditional methods suitable for resource-limited settings.
  • A systematic review of 2725 articles identified 13 that met criteria for evaluating the performance of the DD method in assessing triazole susceptibility in Aspergillus species, showing varying agreement levels with the reference CLSI method.
  • Results indicated that while the agreement for itraconazole was lower (70.75%) when using non-standard media, the DD method demonstrated high agreement (>94%) for voriconazole and posaconazole across all media, suggesting its potential as a reliable option for routine antifungal susceptibility testing
View Article and Find Full Text PDF

Aspergillus fumigatus is an environmental mold that causes life-threatening respiratory infections in immunocompromised patients. The plateaued effectiveness of antifungal therapy and the increasing prevalence of triazole-resistant isolates have led to an urgent need to optimize and expand the current treatment options. For the transition of research to models in the time- and resource-consuming preclinical drug development pipeline, Galleria mellonella larvae have been introduced as a valuable screening intermediate.

View Article and Find Full Text PDF

Invasive pulmonary aspergillosis has emerged as a frequent coinfection in severe coronavirus disease (COVID-19), similarly to influenza, yet the clinical invasiveness is more debated. We investigated the invasive nature of pulmonary aspergillosis in histology specimens of influenza and COVID-19 ICU fatalities in a tertiary care center. In this monocentric, descriptive, retrospective case series, we included adult ICU patients with PCR-proven influenza/COVID-19 respiratory failure who underwent postmortem examination and/or tracheobronchial biopsy during ICU admission from September 2009 until June 2021.

View Article and Find Full Text PDF

Pulmonary mycoses are an important threat for immunocompromised patients, and although current treatments are effective, they suffer from multiple limitations and fail to further reduce mortality. With the increasing immunocompromised population and increased antifungal resistance, fungal infection research is more relevant than ever. In preclinical respiratory fungal infection research, animal models are indispensable.

View Article and Find Full Text PDF

Aspergillus fumigatus and Cryptococcus neoformans species infections are two of the most common life-threatening fungal infections in the immunocompromised population. Acute invasive pulmonary aspergillosis (IPA) and meningeal cryptococcosis are the most severe forms affecting patients with elevated associated mortality rates despite current treatments. As many unanswered questions remain concerning these fungal infections, additional research is greatly needed not only in clinical scenarios but also under controlled preclinical experimental settings to increase our understanding concerning their virulence, host-pathogen interactions, infection development, and treatments.

View Article and Find Full Text PDF

Increasing resistance to triazole antifungals in is worrisome because of the associated high mortality of triazole-resistant (TRAF) infections. While most studies have focused on single triazole-susceptible (WT) or TRAF infections, reports of TRAF cases developing mixed WT and TRAF infections have been described in several studies. However, the prevalence of mixed infections and their responses to current recommended therapies are unknown and could be inappropriate, leading to poor clinical outcomes.

View Article and Find Full Text PDF

Unlabelled: Emergence of triazole resistance has been observed in Aspergillus fumigatus over the past decade including Africa. This review summarizes the current published data on the epidemiology and reported mechanisms of triazole-resistant Aspergillus fumigatus (TRAF) in both environmental and clinical isolates from Africa. Searches on databases Medline, PubMed, HINARI, Science Direct, Scopus and Google Scholar on triazole resistance published between 2000 and 2021 from Africa were performed.

View Article and Find Full Text PDF

Invasive pulmonary aspergillosis (IPA) caused by the mold Aspergillus fumigatus is one of the most important life-threatening infections in immunocompromised patients. The alarming increase of isolates resistant to the first-line recommended antifungal therapy urges more insights into triazole-resistant A. fumigatus infections.

View Article and Find Full Text PDF

Invasive pulmonary aspergillosis (IPA) is a life-threatening fungal infection occurring mainly in immunocompromised patients. We recently identified IPA as an emerging co-infection with high mortality in critically ill, but otherwise immunocompetent influenza patients. The neuraminidase inhibitor oseltamivir is the current standard-of-care treatment in hospitalized influenza patients; however, its efficacy in influenza-associated pulmonary aspergillosis (IAPA) is not known.

View Article and Find Full Text PDF

Background: Prevalence reports of triazole-resistance in Aspergillus fumigatus differ between countries and centers and may likewise vary over time. Continuous local surveillance programs to establish the evolving epidemiology of triazole-resistance in A. fumigatus are crucial to guide therapeutic recommendations.

View Article and Find Full Text PDF

Influenza-associated pulmonary aspergillosis (IAPA) has been reported increasingly since the advent of use of neuraminidase (NA) inhibitors following the 2009 influenza pandemic. We hypothesize that blocking host NA modulates the immune response against . We demonstrate that NA influences the host response against and that oseltamivir increases the susceptibility of mice to pulmonary aspergillosis.

View Article and Find Full Text PDF

Triazole-resistance has been reported increasingly in . An international expert team proposed to avoid triazole monotherapy for the initial treatment of invasive aspergillosis in regions with >10% environmental-resistance, but this prevalence is largely unknown for most American and African countries. Here, we screened 584 environmental samples (soil) from urban and rural locations in Mexico, Paraguay, and Peru in Latin America and Benin and Nigeria in Africa for triazole-resistant .

View Article and Find Full Text PDF
Article Synopsis
  • - A study was conducted in Burkina Faso to investigate the prevalence of azole-resistant (ARAF) strains due to limited data on these strains in Africa, highlighting environmental factors that suggest their presence.
  • - Researchers collected and analyzed 120 soil samples, utilizing azole-containing agar plates for resistance screening and the EUCAST method to confirm resistance.
  • - Among the samples, one ARAF isolate (2%) was identified, carrying specific mutations, marking the first report of azole resistance in Burkina Faso.
View Article and Find Full Text PDF

Recently, mutations in the -encoding gene (), a gene involved in ergosterol production, were associated with triazole-resistance in . In this study, we determined the prevalence and characteristics of mutations in a collection of clinical triazole-resistant isolates collected during 2001-2019 from two international mycology reference centers: the Belgian National Reference Center for Mycosis and the Center of Expertise in Mycology Radboudumc/CWZ. Clinical isolates with and without gene mutations and randomly selected wild-type (WT) controls were included.

View Article and Find Full Text PDF

is an opportunistic fungal pathogen in patients with immunodeficiency, and virulence of isolates has mainly been studied in the context of chronic granulomatous disease (CGD), with characterization of clinical isolates obtained from non-CGD patients remaining elusive. This study therefore carried out a detailed biological characterization of two clinical isolates (CIs), obtained from a patient with breast carcinoma and pneumonia and from a patient with cystic fibrosis that underwent lung transplantation, and compared them to the reference, nonclinical FGSC A4 strain. Both CIs presented increased growth in comparison to that of the reference strain in the presence of physiologically relevant carbon sources.

View Article and Find Full Text PDF

Background: Invasive pulmonary aspergillosis (IPA) remains a life-threatening opportunistic infection, but can be difficult to diagnose. New biomarkers are therefore needed. Gliotoxin (GT), a secondary metabolite of Aspergillus fumigatus, and bis(methylthio)gliotoxin (bmGT), a degradation product of GT, have been proposed as potential biomarkers.

View Article and Find Full Text PDF
Article Synopsis
  • Aspergillus fumigatus resistance to voriconazole, a common antifungal, poses a significant risk, particularly in hematology patients, with reported mortality rates ranging from 50% to 100%.
  • A study on 129 culture-positive invasive aspergillosis cases found 20.2% were voriconazole-resistant, with most resistant strains having specific mutations.
  • The research showed that non-ICU patients with voriconazole-resistant infections had a noticeably higher mortality rate at 12 weeks compared to those with susceptible infections, highlighting the urgency of addressing this resistance problem.
View Article and Find Full Text PDF

Triazole resistance is an increasing concern in the opportunistic mold Aspergillus fumigatus. Resistance can develop through exposure to azole compounds during azole therapy or in the environment. Resistance mutations are commonly found in the Cyp51A-gene, although other known and unknown resistance mechanisms may be present.

View Article and Find Full Text PDF