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Background: Damage due to respiratory viruses increases the risk of bacterial and fungal coinfections and superinfections. High rates of invasive aspergillosis are seen in severe influenza and COVID‐19. This report describes CAPA cases diagnosed during the first wave in the biggest reference centre for severe COVID‐19 in Mexico. Objectives: To describe the clinical, microbiological and radiological characteristics of patients with invasive pulmonary aspergillosis associated with critical COVID‐19, as well as to describe the variables associated with mortality. Methods: This retrospective study identified CAPA cases among individuals with COVID‐19 and ARDS, hospitalised from 1 March 2020 to 31 March 2021. CAPA was defined according to ECMM/ISHAM consensus criteria. Prevalence was estimated. Clinical and microbiological characteristics including bacterial superinfections, antifungal susceptibility testing and outcomes were documented. Results: Possible CAPA was diagnosed in 86 patients among 2080 individuals with severe COVID‐19, representing 4.13% prevalence. All CAPA cases had a positive respiratory culture for Aspergillus species. Aspergillus fumigatus was the most frequent isolate (64%, n = 55/86). Seven isolates (9%, n = 7/80) were resistant to amphotericin B (A. fumigatus n = 5/55, 9%; A. niger, n = 2/7, 28%), two A. fumigatus isolates were resistant to itraconazole (3.6%, n = 2/55). Tracheal galactomannan values ranged between 1.2 and 4.05, while serum galactomannan was positive only in 11% (n = 3/26). Bacterial coinfection were documented in 46% (n = 40/86). Gram negatives were the most frequent cause (77%, n = 31/40 isolates), from which 13% (n = 4/31) were reported as multidrug‐resistant bacteria. Mortality rate was 60% and worse prognosis was seen in older persons, high tracheal galactomannan index and high HbA1c level. Conclusions: One in 10 individuals with CAPA carry a resistant Aspergillus isolate and/or will be affected by a MDR bacteria. High mortality rates are seen in this population. [ABSTRACT FROM AUTHOR]

Malassezia species are a major part of the normal mycobiota and colonize mainly sebum-rich skin regions of the body. This group of fungi cause a variety of infections such as pityriasis versicolor, folliculitis, and fungaemia. In particular, Malassezia sympodialis and its allergens have been associated with non-infective inflammatory diseases such as seborrheic dermatitis and atopic eczema. The aim of this study was to investigate the host response to M. sympodialis on oily skin (supplemented with oleic acid) and non-oily skin using an ex vivo human skin model. Host-pathogen interactions were analyzed by SEM, histology, gene expression, immunoassays and dual species proteomics. The skin response to M. sympodialis was characterized by increased expression of the genes encoding β-defensin 3 and RNase7, and by high levels of S100 proteins in tissue. Supplementation of oleic acid onto skin was associated with direct contact of yeasts with keratinocytes and epidermal damage. In oily conditions, there was increased expression of IL18 but no expression of antimicrobial peptide genes in the skin's response to M. sympodialis. In supernatants from inoculated skin plus oleic acid, TNFα, IL-6, and IL1-β levels were decreased and IL-18 levels were significantly increased. [ABSTRACT FROM AUTHOR]

Human skin fungal infections (SFIs) affect 25% of the world's population. Most of these infections are superficial. The main limitation of current animal models of human superficial SFIs is that clinical presentation is different between the different species and animal models do not accurately reflect the human skin environment. An ex vivo human skin model was therefore developed and standardised to accurately model SFIs. In this manuscript, we report our protocol for setting up ex vivo human skin infections and report results from a primary superficial skin infection with Trichophyton rubrum , an anthropophilic fungus. The protocol includes a detailed description of the methodology to prepare the skin explants, establish infection, avoid contamination, and obtain high quality samples for further downstream analyses. Scanning electronic microscopy (SEM), histology and fluorescent microscopy were applied to evaluate skin cell viability and fungal morphology. Furthermore, we describe a broad range of assays, such as RNA extraction and qRT-PCR for human gene expression, and protein extraction from tissue and supernatants for proteomic analysis by liquid chromatography-mass spectrometry (LC-MS/MS). Non-infected skin was viable after 14 days of incubation, expressed genes and contained proteins associated with proliferative, immune and differentiation functions. The macroscopic damage caused by T. rubrum had a similar appearance to the one expected in clinical settings. Finally, using this model, the host response to T. rubrum infection can be evaluated at different levels. [ABSTRACT FROM AUTHOR]

Mucormycosis is an emerging infectious disease with high rates of associated mortality and morbidity. Little is known about the characteristics of mucormycosis or entomophthoromycosis occurring in Mexico. A search strategy was performed of literature published in journals found in available databases and theses published online at Universidad Nacional Auto' noma de Me'xico (UNAM) library website reporting clinical cases or clinical case series of mucormycosis and entomophthoromycosis occurring in Mexico between 1982 and 2016. Among the 418 cases identified, 72% were diabetic patients, and sinusitis accounted for 75% of the reported cases. Diabetes mellitus was not a risk factor for entomophthoromycosis. Mortality rate was 51% (125/244). Rhizopus species were the most frequent isolates (59%, 148/250). Amphotericin B deoxycholate was used in 89% of cases (204/227), while surgery and antifungal management as combined treatment was used in 90% (172/191). In diabetic individuals, this combined treatment approach was associated with a higher probability of survival (95% vs 66%, OR = 0.1, 95% CI, 0.02-0.43' P = .002). The most common complications were associated with nephrotoxicity and prolonged hospitalization due to IV antifungal therapy. An algorithm is proposed to establish an early diagnosis of rhino-orbital cerebral (ROC) mucormycosis based on standardized identification of warning signs and symptoms and performing an early direct microbiological exam and histopathological identification through a multidisciplinary medical and surgical team. In summary, diabetes mellitus was the most common risk factor for mucormycosis in Mexico; combined antifungal therapy and surgery in ROC mucormycosis significantly improved survival. [ABSTRACT FROM AUTHOR]

Candidemia is the predominant form of invasive candidiasis and the most frequently occurring serious fungal infection in critically ill patients in Intensive Care Units (ICU). Studies carried out in Latin America reveal a higher incidence of candidemia and higher mortality rates when compared to North America or Europe. This highlights the need to develop guidelines for correctly diagnosing and treating candidemia in critically ill patients in the ICU. These guidelines are part of the efforts to implement antifungal optimization programs in the region to obtain better clinical outcomes and promote rational antifungal use. This evidence-based clinical standard, established through expert consensus for the Latin American context, contains recommendations and algorithms for diagnosing and treating candidemia in critically ill ICU patients., Competing Interests: Conflicts of interest The following authors declared that they have no conflict of interest: MSJ, CDB, RRR, CJEA, LCN. The following authors declared conflicts of interest: JAC (Pfizer), MCV (Pfizer), PMP (GlaxoSmithKline), MN (Mundipharma, Knight Therapeutics, Cidara Therapeutics), CAA (Moderna, Merck Sharp & Dohme, GlaxoSmithKline, Becton Dickinson, Pfizer), FQT (IMMY, Sandoz, Mundipharma), RR (Gilead Sciences, Gador, Pfizer), RRF (Pfizer, Gilead Sciences, Merck Sharp & Dohme), FR (Gilead Sciences, Janssen: Pharmaceutical Companies of Johnson & Johnson), PC (Pfizer, Merck Sharp & Dohme), DEC (IMMY), LECP (Knight Therapeutics), JZ (Pfizer), ARH (Octapharma, Pfizer, Medtronic), ALC (Grant from the Research Support Foundation of the State of São Paulo [FAPESP], number 2021/10,599–3), without identifying declared interests that could be considered potentially conflicting with the primary interest of this EBCS., (Copyright © 2024 Sociedade Brasileira de Infectologia. Published by Elsevier España, S.L.U. All rights reserved.)

Background: Mucormycosis is an aggressive, invasive fungal infection caused by moulds in the order Mucorales. Early diagnosis is key to improving patient prognosis, yet relies on insensitive culture or non-specific histopathology. A pan-Mucorales specific monoclonal antibody (mAb), TG11, was recently developed. Here, we investigate the spatio-temporal localisation of the antigen and specificity of the mAb for immunohistochemistry., Methods: We use immunofluorescence (IF) microscopy to assess antigen localisation in eleven Mucorales species of clinical importance and live imaging of Rhizopus arrhizus germination. Immunogold transmission electron microscopy (immunoTEM) reveals the sub-cellular location of mAb TG11 binding. Finally, we perform immunohistochemistry of R. arrhizus in an ex vivo murine lung infection model alongside lung infection by Aspergillus fumigatus., Results: IF revealed TG11 antigen production at the emerging hyphal tip and along the length of growing hyphae in all Mucorales except Sakasenea. Timelapse imaging revealed early antigen exposure during spore germination and along the growing hypha. ImmunoTEM confirmed mAb TG11 binding to the hyphal cell wall only. The TG11 mAb specifically stained Mucorales but not Aspergillus hyphae in infected murine lung tissue., Conclusions: TG11 detects early hyphal growth and has valuable potential for diagnosing mucormycosis by enhancing discriminatory detection of Mucorales in tissue., (© The Author(s) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)

Members of the Meyerozyma guilliermondii species complex are able to cause superficial and life-threatening systemic infections with low susceptibility to azoles and echinocandins. We tested 130 bloodstream M. guilliermondii complex isolates collected from eight Latin American medical centers over 18 years (period 1 = 2000-2008 and period 2 = 2009-2018) to investigate trends in species distribution and antifungal resistance. The isolates were identified by rDNA ITS region sequencing, and antifungal susceptibility tests were performed against fluconazole, voriconazole, anidulafungin, and amphotericin B using the CLSI microbroth method. M. guilliermondii sensu stricto (s.s.; n = 116) was the most prevalent species, followed by Meyerozyma caribbica ( n = 12) and Meyerozyma carpophila ( n = 2). Based on rDNA ITS identification, three clades within M. guilliermondii sensu stricto were characterized (clade 1 n = 94; clade 2 n = 19; and clade 3 n = 3). In the second period of study, we found a substantial increment in the isolation of M. caribbica (3.4% versus 13.8%; P = 0.06) and clade 2 M. guilliermondii s.s. exhibiting lower susceptibility to one or more triazoles. IMPORTANCE Yeast-invasive infections play a relevant role in human health, and there is a concern with the emergence of non- Candida pathogens causing disease worldwide. There is a lack of studies addressing the prevalence and antifungal susceptibility of different species within the M. guilliermondii complex that cause invasive infections. We evaluated 130 episodes of M. guilliermondii species complex candidemia documented in eight medical centers over 18 years. We detected the emergence of less common species within the Meyerozyma complex causing candidemia and described a new clade of M. guilliermondii with limited susceptibility to triazoles. These results support the relevance of continued global surveillance efforts to early detect, characterize, and report emergent fungal pathogens exhibiting limited susceptibility to antifungals.

Candida auris can persist for long periods on hospital surfaces and on the skin. C. auris has the ability to form drug-resistant biofilms, which can substantially impact on patient outcome. In comparison to Candida albicans, C. auris has a lower capacity to form biofilms in in vitro models and a higher capacity when tested on animal skin models. Intraspecies variation is shown to exist, with some clinical isolates having greater biofilm capabilities than others. There is a need for models that closely mimic the real niches where infection occurs on human patients. This protocol describes, in detail, a human skin model to study C. auris biofilm formation using catheterized and non-catheterized skin., (© 2022. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

In individuals with HIV/AIDS, 47% of the deaths are attributed to invasive fungal infections (IFIs), despite antiretroviral (ARV) therapy. This is a retrospective study carried out in the Hospital Regional de Alta Especialidad Oaxaca (HRAEO), southwest Mexico, where IFIs that occurred during 2016⁻2017 are described. A total of 55 individuals were included. Histoplasmosis (36%) and possible-IFIs in neutropenic fever (20%) were the most frequent cases, followed by cryptococcosis (14%). The HIV/AIDS subpopulation corresponded with 26 cases (47%), all from an indigenous origin. The incidence of IFIs among them was 24% (95% CI = 15⁻33%). The CD4+ T cells median was 35 cells/mL (IQR 12⁻58). Four cases (15%) of unmasking IRIS were identified, three of histoplasmosis and one coccidioidomycosis. Co-infections were found in 52% (12/23), and tuberculosis in 50% (6/12) was the most frequent. The mortality rate was 48%. The general characteristics of the HIV individuals who died were atypical pneumonia (70% vs. 9%, p = 0.01), acute kidney injury, (70% vs. 9%, p = 0.008) and ICU stay (80% vs. 9%, p = 0.002). In conclusion, IFIs are diagnosed in one out of four individuals with HIV/AIDS along with other complicated infectious conditions, leading to major complications and a high mortality rate.

Background: Serum levels of aldosterone in heart failure are increased up to 20 times compared to normal subjects. After an acute myocardial infarction, aldosterone increases progressively as well as interstitial fibrosis and collagen synthesis from cardiac fibroblasts, forming a patchy heterogeneous interstitial collagen matrix that affects ventricular function. Even if angiotensin converting enzyme inhibitors (ACEI) or angiotensin II receptor antagonists (ARA) can reduce aldosterone levels early during treatment, they increase again after a 12 week treatment. The aim of this study was to evaluate the changes in structure and function of the left ventricle in symptomatic (NYHA I-III) diastolic heart failure patients receiving an aldosterone receptor antagonist., Methods: Twenty-eight subjects with diastolic heart failure, on BB, ACEI and/ or ARA were randomized to receive spironolactone (group A) on a mean dose of 37.5 mg once a day (n = 14, age 63.7 +/- 21.6 years and body mass index, BMI 27.5 +/- 9.4), or not (group B, n = 14, Age 64.8 +/- 11.9, BMI 26.9 +/- 4.7). All patients were followed-up for a mean of 13.79 +/- 0.99 months., Results: Group A showed a 42.8% ischemic origin of heart failure, while in group B was 55% (p = 0.2). No other co-morbidities were significativelly different among both groups. Mean percentage of changes by echocardiogram was as follows: Interventricular septum (IVS) -12.2 +/- 11% vs. 1.3 +/- 15.2 (p = 0.03), pulmonary systolic artery pressure (PSAP was 0.99 +/- 3.8% vs. 10.5 +/- 9.1, p = 0.05). Other parameters did not show statistically significant differences., Conclusion: Aldosterone receptor antagonists reduce or avoid increasing of PSAP and inducing a favorable remodeling of the left ventricle, especially in the IVS in diastolic heart failure patients.