Cryptococcosis predominantly affects immunocompromised individuals, particularly those with advanced HIV disease, with meningitis being the most severe form and linked to high mortality. Diagnosis typically relies on rapid Cryptococcus antigen (CrAg) testing, and antigen titer quantification helps in early detection and assessing disease severity. However, conventional titer methods are often more expensive than qualitative antigen detection. This study assessed the diagnostic performance of a semi-quantitative lateral flow assay (CrAgSQ LFA, IMMY™) for CrAg detection in serum and cerebrospinal fluid (CSF) collected between 2014 and 2022. The CrAgSQ LFA was compared to the standard CrAg LFA (IMMY™) and Clarus Cryptococcal Ag enzyme immunoassay (EIA-CrAg, IMMY™). The CrAgSQ LFA demonstrated 100% sensitivity and specificity in both serum and CSF, with perfect agreement (kappa 1.00) with the CrAg LFA. When comparing the CrAgSQ LFA with the titer measurement results obtained using CrAg LFA, titers ranged as follows: in category 1+, from 1:2 to 1:20; in 2+, from 1:5 to 1:40; in 3+, from 1:20 to 1:2560; and in 4+, from 1:320 to 1:2560. Titer results for the CrAgSQ LFA aligned well with CrAg LFA, and operator agreement was strong, with weighted kappa values of 0.926 and 0.966. The CrAg-EIA showed a sensitivity of 84% and specificity of 100% using the manufacture cutoff (>0.265), which improved to 96% sensitivity with an optimized cutoff value (>0.145). Overall, the CrAgSQ LFA demonstrated high accuracy and reliability, suggesting it could be a valuable tool for diagnosing cryptococcosis in the Americas.

Los hongos son organismos polifacéticos presentes en casi todos los ecosistemas de la tierra, donde establecen diversos tipos de simbiosis con otros seres vivos. A pesar de ser reconocidos por los humanos desde la antigüedad –y de la cantidad de trabajos que han profundizado sobre su biología y ecología–, aún falta mucho por conocer sobre estos organismos.Algunos de los criterios que clásicamente se han utilizado para su estudio, hoy resultan limitados y hasta cierto punto permiten un agrupamiento de los aislamientos según algunas características, pero generan confusión en su clasificación y, más aún, cuando se pretende comprender sus relaciones genealógicas.Los caracteres fenotípicos no son suficientes para identificar una especie de hongos y, menos aún, para construir una filogenia amplia o de un grupo particular. Hay grandes vacíos que hacen que los árboles generados sean inestables y fácilmente debatidos.Para los profesionales de la salud, parece que la identificación de los hongos hasta niveles inferiores como género y especie es suficiente para elegir el tratamiento más adecuado para su control, comprender la epidemiología de los cuadros clínicos asociados y reconocer los brotes y los factores determinantes de la resistencia a los antimicrobianos. No obstante, la ubicación taxonómica dentro del reino permitiría establecer relaciones filogenéticas entre los taxones fúngicos, facilitando la comprensión de su biología, su distribución en la naturaleza y la evolución de su potencial patogénico.

Introduction. For over a century, Sporothrix schenckii was considered the sole species responsible for sporotrichosis. In 2007, scientific community confirmed the disease could be caused by various Sporothrix species. These species differed in their virulence factors and their antifungal sensitivity.Objective. This study aims to characterize 42 Colombian clinical isolates of Sporothrix spp. phenotypically and genotypically.Material and methods. Forty-two clinical isolates were characterized using phenotypic methods. It involved various culture media to determine their growth range at different temperatures and to assess the type and distribution of pigment and colony texture. Microscopic morphology was evaluated through microcultures, as well as the conidia diameter, type of sporulation, and morphology. Additionally, the assimilation of carbohydrates was selected as a physiological trait for species identification. Genotyping of 40 isolates was performed through partial amplification of the calmodulin gene, followed by sequence analysis.Results. Molecular studies enabled the identification of 32 isolates of S. schenckii and 8 isolates of S. globosa. The combination of phenotypic and genotypic methods eased these species characterizations and the recognition keys development based on parameters such as growth diameter at 25 and 30 ºC, colony texture (membranous or velvety) on potato dextrose agar, and microscopic morphology with predominance of pigmented triangular, elongated oval globose, or subglobose conidia.Conclusions. Confirmation of the phenotypic characteristics and molecular analysis is crucial for identifying Sporothrix species and determining adequate treatment. This study represents the first phenotypical and genotypical characterization of clinical isolates of Sporothrix spp. reported in Colombia.

The genus Aspergillus comprises a diverse group of fungi that can cause a range of health issues, including systemic infections and allergic reactions. In this regard, A. fumigatus has been recognized as the most prevalent allergen-producing species. This genus taxonomic classification has been subject to frequent updates, which has generated considerable difficulties for its classification when traditional identification methodologies are employed. To demonstrate the feasibility of this approach, we sequenced the whole genomes of 81 Aspergillus isolates and evaluated a WGS-based pipeline for precise species identification. This pipeline employed two methodologies: (i) BLASTn web using four barcode genes and (ii) species tree inference by OrthoFinder. Furthermore, we conducted a prediction of allergenic capacity based on a homology analysis across all the isolated species and confirmed by RT-qPCR the expression of three orthologous allergens (Asp f 1, Asp f 3 and Asp f 22) in fifteen different Aspergillus species. The species-level identification rate with the barcoding and the species tree were calculated at 64.2% and 100%, respectively. The results demonstrated that A. fumigatus, A. flavus and A. niger were the most prevalent species. The species A. hortae, A. uvarum, A. spinulosporus, A. sydowii, A. westerdijkiae, A. amoenus and A. rhizopodus identified in this study represent the inaugural report of their presence in our region. The results of the homology analysis indicated the presence of orthologous allergens in a wide range of non-fumigatus species. This study presents a novel approach based on WGS that enables the classification of new species within the genus Aspergillus and reports the genomic sequences of a great diversity of species isolated in our geographic area that had never been reported before. Additionally, this approach enables the prediction of allergens in species other than A. fumigatus and demonstrates their genetic expression, thereby contributing to the understanding of the allergenic potential of different species within this fungal genus.

Fungal contamination in closed or open environments has been well reported. However, studies that address airborne spores trap methods are scarce. In this study, two techniques were evaluated to detect fungal spores in the environment of three buildings of campus of a university in the city of Cali, Colombia. The gravimetric method of spore trapping was compared with the volumetric method (Air Ideal 3P) using the Omeliansky formula to determine the spore abundance. Environmental sampling was performed quarterly for a period of 12 months using dichloran rose bengal chloramphenicol agar. A total of 64,497 CFU/m3 were counted, of which 34,930 CFU/m3 were isolated using the volumetric method and 29,567 CFU/m3 using the gravimetric method. No significant statistical differences were observed between the two techniques (P = 0.0739). The predominant genera obtained with both methods were Cladosporium, Penicillium, Aspergillus, and Fusarium, which suggests that although the gravimetric method is not as efficient as the volumetric method, it is reliable in estimating environmental fungal contamination.