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The National Reference Laboratory in Clinical Mycology of Argentina conducted a retrospective review of human coccidioidomycosis cases diagnosed by the National Mycology Laboratory Network of Argentina between 2010 and 2022 to determine the burden of the disease in the country. A total of 100 human coccidioidomycosis cases were documented, with a higher prevalence in male patients (male-to-female ratio of 1.9:1), with a median age of 41 years. Comparing the number of cases between two 10-year periods (2000-2009 and 2010-2019), the increase was 36.51% (from 63 to 86 cases). Among the 100 recorded cases, 79 tested positive using the double immunodiffusion test. Spherules were observed in 19 cases through histopathology or direct microscopic examination and the fungus was isolated in 39 cases. Thirty-six isolates were identified as Coccidioides posadasii through partial sequencing of the Ag2/PRA gene. Catamarca province had the highest number of cases, comprising 64% of the total, with an incidence rate above 1.0-2.5/100,000 inhabitants until 2018. However, there has been a recent downward trend in the region from 2018 to 2022. It is concerning that more than half of diagnosed cases were chronic pulmonary or disseminated forms, indicating a lack of early disease detection. To rectify this issue, it is imperative to conduct targeted training programs for healthcare personnel and enhance public awareness within the endemic area. This will contribute to a better understanding of the true burden of coccidioidomycosis and enable the implementation of appropriate sanitary control measures., (© The Author(s) 2024. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

Coccidiomycosis is a potentially life-threatening fungal infection endemic to certain regions of Argentina. The infection is caused by Coccidioides spp. and is primarily diagnosed by Coccidioides antibody (Ab) detection. Access to rapid, highly accurate diagnostic testing is critical to ensure prompt antifungal therapy. The sōna Coccidioides Ab Lateral Flow Assay (LFA) performs faster and requires less laboratory infrastructure and equipment compared with other Ab detection assays, potentially providing a substantial improvement for rapid case screening in coccidioidomycosis-endemic regions; however, validation of this test is needed. Thus, we aimed to evaluate the analytical performance of the sōna Coccidioides Ab (LFA) and compare agreement with anti- Coccidioides Ab detection assays. A total of 103 human sera specimens were tested, including 25 specimens from patients with coccidioidomycosis and 78 from patients without coccidioidomycosis. The sōna Coccidioides Ab Lateral Flow Assay (LFA) was performed with a sensitivity of 88%, and specificity and accuracy of 87%. Furthermore, the Coccidioides Ab LFA had good agreement with other anti- Coccidioides Ab detection assays. Our findings suggest the sōna Coccidioides Ab LFA has satisfactory performance and may be useful for diagnosing coccidioidomycosis in endemic regions.

This study aimed to perform a seroepidemiological survey on the prevalence of sporotrichosis among cats living in the Northern area of Buenos Aires, where a four-fold increase of Sporothrix brasiliensis infections were diagnosed during the last decade. For this purpose, an in-house indirect ELISA test sensitized with S. brasiliensis crude antigens was used. The ELISA test showed 100.0% sensitivity and 95.0% specificity. Antibodies against S. brasiliensis antigens were detected in 3.7% (9/241) of healthy cats evaluated, suggesting likely exposure or infection to this fungus. This ELISA test would be a valuable screening tool for diagnosing sporotrichosis and for seroepidemiological surveys., (© The Author(s) 2023. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

We report a case of disseminated histoplasmosis and COVID-19 infection in a renal transplant recipient in Argentina. The patient exhibited respiratory symptoms, and a chest computed tomography scan (CT) showed multiple bilateral centrilobular opacities with a tree-in-bud pattern in both lobes. The patient was initially treated as having bacterial community-acquired pneumonia, and then tuberculosis. A month later, histoplasmosis was diagnosed, and Histoplasma capsulatum LAmB clade was isolated from sputum, skin and oral lesions. The patient was hospitalized and treatment was started with intravenous liposomal amphotericin B. During the course of the antifungal therapy the respiratory symptoms worsened, a new chest CT showed a unilateral lesion with a ground glass appearance and SARS-CoV-2 was detected in a new nasopharyngeal sample. In addition, plasma therapy was administered, and the immunosuppressive regimen was adjusted (everolimus was interrupted, mycophenolate mofetil reduced, and meprednisone increased). Finally, the patient's progress was favorable and was discharged after five days on oral itraconazole treatment for histoplasmosis., (Copyright © 2021 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.)

Histoplasmosis is a worldwide systemic endemic mycosis caused by several cryptic species included within the Histoplasma capsulatum complex. Domestic and wild mammals are susceptible to infection by this fungus and could be used as indicators of its presence in the environment. The aim of the study was to identify the natural reservoirs of H. capsulatum in the Argentinean Humid Pampas eco-region analyzing a wildlife frozen-tissue collection and trace its distribution patterns over time and space. Tissue samples from 34 small wild mammals caught in the Humid Pampas were analyzed using two molecular markers: 100 kDa protein coding gene (Hcp100) and ITS1 rDNA. Results showed that 32.4% of them were infected with H. capsulatum and its DNA was detected in 5/17 Calomys laucha; 3/6 Calomys musculinus; 1/5 Akodon azarae, 1/3 Monodelphis dimidiata; and 1/2 Didelphis albiventris. In the single specimen studied of Cavia aperea, no H. capsulatum DNA was detected. This is the first H. capsulatum infection report in C. laucha and C. musculinus rodents and M. dimidiate opossum which proves that tissue collections are an important source of material for epidemiological studies of endemic disease over time.

Coccidioides immitis and C. posadasii are the etiologic agents of coccidioidomycosis, an endemic fungal disease of the Americas. In Colombia, this mycosis is uncommon, and only five cases, two of them imported, have been documented.By means of DNA sequencing, C. immitis was identified in formalin-fixed, paraffin-embedded archival tissues samples from the 5th Colombian patient diagnosed in 1997. The patient was born in Pinto, Department of Magdalena, and had never visited other geographic regions, a reason to consider that the mycosis had been acquired locally.This species is primarily found in California although it has been occasionally reported in other geographic areas such as Mexico and Brazil. This is the first indigenous report of C. immitis-associated coccidioidomycosis in a Colombian patient., (© The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

Background: A multicenter study was conducted. A panel containing DNA from Histoplasma capsulatum, as well as negative and cross-reaction controls, was sent to five different laboratories, members of the MICOMOL network from CYTED Program., Aims: The objective was to assess the accuracy of different PCR protocols to detect H. capsulatum DNA., Methods: Seven different PCR protocols were tested. They were based on PCR techniques and used unicopy and multicopy targets., Results: Most of these protocols (4/7) were able to detect the smallest amounts of fungal DNA (10(2)fg/μl). Overall sensitivity was 86% and specificity was 100%. The protocol based on a unicopy target (SCAR220) presented lower sensitivity (43%) but 100% specificity. The real-time protocols tested were highly reproducible, sensitive, and specific. Neither false positives nor cross-reactions were detected in any protocol., Conclusions: All laboratories were able to amplify H. capsulatum DNA, and real-time PCR seems to be a promising tool to efficiently detect this pathogen in clinical samples., (Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.)

Background: Histoplasma capsulatum is the agent of histoplasmosis, a deep mycosis mainly afflicting immunocompromised patients. Rapid identification of the fungus isolated from clinical specimens allows timely administration of specific treatment., Aim: To assess the ability of a dual PCR system targeting specific H. capsulatum DNA sites to identify fungal species in simple aqueous lysates from cultured fungi., Methods: We analysed the performance of two independent PCR reactions designed to amplify fragments of 111 and 279 bp included in H. capsulatum-specific gene AgM. We used 248 H. capsulatum strains and 68 isolates of other fungal species. Reaction templates consisted of aqueous lysates of cultured fungi (either in mycelial or yeast phase) obtained after three cycles of boiling and immediate cooling at 0°C. Selected strains were submitted to conventional DNA extraction and/or sequencing., Results: Both PCR systems performed identically. Amplification from aqueous lysates was achieved from 239 H. capsulatum strains; the remaining 9 strains only showed specific bands when purified DNA was used as template. Of all other fungal species tested, only 2 Emmonsia crescens strains amplified H. capsulatum-specific bands and sequences of their amplified PCR products matched > 97% with H. capsulatum sequences. Total test time did not exceed 7h with 96% sensitivity, 97% specificity and 99% positive predictive value., Conclusions: The assay is fast, accurate and economical, and can be an alternative method for presumptive identification of H. capsulatum in simple culture lysates., (Copyright © 2010 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.)

To assess the value of using whole blood samples for the molecular diagnosis of histoplasmosis, we applied an in-house DNA extraction method and a nested PCR targeting a 210 bp specific segment of the Histoplasma capsulatum HcP100 gene. A whole blood volume of 2.5-3 milliliters was centrifuged and the cellular pellet was treated with Trichoderma harzianum lyticase and proteinase K prior to applying a conventional phenol DNA extraction. This procedure allowed complete cell lysis, high DNA yield and specific amplification. The PCR detection limit was 0.25-1 yeast cells/ml of blood sample. The method was assessed on 31 blood samples from 19 patients with microbiological diagnosis of histoplasmosis, 30 healthy persons and 21 patients with other mycoses or mycobacterial diseases. Positive results were obtained in samples from 17/19 patients with histoplasmosis (14/15 immunocompromised and 3/4 without known immunological disorder). Blood samples from the 30 healthy controls and 20 patients with other conditions proved negative; the only false positive result was obtained from a patient with Mycobacterium avium-intracellulare infection. With 89% sensitivity and 98% specificity, this molecular method for detection of the agent in blood shows promising for the rapid diagnosis of human histoplasmosis.