Diagnostic accuracy of antigen detection in urine and molecular assays testing in different clinical samples for the diagnosis of progressive disseminated histoplasmosis in patients living with HIV/AIDS: A prospective multicenter study in Mexico.

BACKGROUND: The progressive disseminated histoplasmosis (PDH) has been associated with severe disease and high risk of death among people living with HIV (PLWHIV). Therefore, the purpose of this multicenter, prospective, double-blinded study done in ten Mexican hospitals was to determine the diagnostic accuracy of detecting Histoplasma capsulatum antigen in urine using the IMMY ALPHA Histoplasma EIA kit (IAHE), clarus Histoplasma GM Enzyme Immunoassay (cHGEI IMMY) and MiraVista Histoplasma Urine Antigen LFA (MVHUALFA); as well as the Hcp100 and 1281-1283220SCAR nested PCRs in blood, bone-marrow, tissue biopsies and urine. METHODOLOGY/PRINCIPAL FINDINGS: We included 415 PLWHIV older than 18 years of age with suspicion of PDH. Using as diagnostic standard recovery of H. capsulatum in blood, bone marrow or tissue cultures, or histopathological exam compatible, detected 108 patients (26%, [95%CI, 21.78-30.22]) with proven-PDH. We analyzed 391 urine samples by the IAHE, cHGEI IMMY and MVHUALFA; the sensitivity/specificity values obtained were 67.3% (95% CI, 57.4-76.2) / 96.2% (95% CI, 93.2-98.0) for IAHE, 91.3% (95% CI, 84.2-96.0) / 90.9% (95% CI, 87.0-94.0) for cHGEI IMMY and 90.4% (95% CI, 83.0-95.3) / 92.3% (95% CI, 88.6-95.1) for MVHUALFA. The Hcp100 nested PCR was performed on 393, 343, 75 and 297, blood, bone marrow, tissue and urine samples respectively; the sensitivity/specificity values obtained were 62.9% (95%CI, 53.3-72.5)/ 89.5% (95%CI, 86.0-93.0), 65.9% (95%CI, 56.0-75.8)/ 89.0% (95%CI, 85.2-92.9), 62.1% (95%CI, 44.4-79.7)/ 82.6% (95%CI, 71.7-93.6) and 34.9% (95%CI, 24.8-46.2)/ 67.3% (95%CI, 60.6-73.5) respectively; and 1281-1283220SCAR nested PCR was performed on 392, 344, 75 and 291, respectively; the sensitivity/specificity values obtained were 65.3% (95% CI, 55.9-74.7)/ 58.8% (95%CI, 53.2-64.5), 70.8% (95%CI, 61.3-80.2)/ 52.9% (95%CI, 46.8-59.1), 71.4% (95%CI, 54.7-88.2)/ 40.4% (95%CI, 26.4-54.5) and 18.1% (95%CI, 10.5-28.1)/ 90.4% (95%CI, 85.5-94.0), respectively. CONCLUSIONS/SIGNIFICANCE: The cHGEI IMMY and MVHUALFA tests showed excellent performance for the diagnosis of PDH in PLWHIV. The integration of these tests in clinical laboratories will certainly impact on early diagnosis and treatment.

Sporotrichosis in Mexico.

Sporotrichosis is an endemic mycosis caused by the species of the Sporothrix genus, and it is considered one of the most frequent subcutaneous mycoses in Mexico. This mycosis has become a relevant fungal infection in the last two decades. Today, much is known of its epidemiology and distribution, and its taxonomy has undergone revisions. New clinical species have been identified and classified through molecular tools, and they now include Sporothrix schenckii sensu stricto, Sporothrix brasiliensis, Sporothrix globosa, and Sporothrix luriei. In this article, we present a systematic review of sporotrichosis in Mexico that analyzes its epidemiology, geographic distribution, and diagnosis. The results show that the most common clinical presentation of sporotrichosis in Mexico is the lymphocutaneous form, with a higher incidence in the 0-15 age range, mainly in males, and for which trauma with plants is the most frequent source of infection. In Mexico, the laboratory diagnosis of sporotrichosis is mainly carried out using conventional methods, but in recent years, several researchers have used molecular methods to identify the Sporothrix species. The treatment of choice depends mainly on the clinical form of the disease, the host's immunological status, and the species of Sporothrix involved. Despite the significance of this mycosis in Mexico, public information about sporotrichosis is scarce, and it is not considered reportable according to Mexico's epidemiological national system, the "Sistema Nacional de Vigilancia Epidemiológica." Due to the lack of data in Mexico regarding the epidemiology of this disease, we present a systematic review of sporotrichosis in Mexico, between 1914 and 2019, that analyzes its epidemiology, geographic distribution, and diagnosis.

The habitat of Coccidioides spp. and the role of animals as reservoirs and disseminators in nature.

BACKGROUND: Coccidioidomycosis, a potentially fatal fungal infection, is considered an emergent mycotic disease because of the increased incidence of fungal infections registered over recent years. Infection occurs through the inhalation of arthroconidia from two main species of Coccidioides: Coccidioides immitis and C. posadasii, which are both endemic to arid and semi-arid regions of North America. Coccidioides species not only infect humans but can also infect other mammals (land, aquatic, wild or domestic), reptiles and birds. OBJECTIVE: To obtain information regarding the habitat of Coccidioides spp. and the animals infected by this fungus and to identify the role that infected animals play as reservoirs and disseminators of this fungus in nature. MATERIALS: A literature review was conducted to identify the habitat of Coccidioides spp. and the infected non-human animal species targeted by this fungus. RESULTS AND CONCLUSIONS: This review allows us to suggest that Coccidioides spp. may be classified as halotolerant organisms; nevertheless, to perpetuate their life cycle, these organisms depend on different animal species (reservoirs) that serve as a link with the environment, by acting as disseminators of the fungi in nature.

Phenotypic characteristics of isolates of Aspergillus section Fumigati from different geographic origins and their relationships with genotypic characteristics.

BACKGROUND: Epidemiological studies worldwide have shown that A. fumigatus exhibits important phenotypic and genotypic diversity, and these findings have been of great importance in improving the diagnosis and treatment of diseases caused by this fungus. However, few studies have been carried out related to the epidemiology of this fungus in Latin America. This study's aim is to report on the epidemiology of the fungus by analyzing the phenotypic variability of Aspergillus section Fumigati isolates from different Latin American countries and the relationship between this variability, the geographical origin and genotypic characteristics. METHODS: We analyzed the phenotypic characteristics (macro- and micromorphology, conidial size, vesicles size, antifungal susceptibility and thermotolerance at 28, 37 and 48°C) of A. section Fumigati isolates from Mexico (MX), Argentina (AR), Peru (PE) and France (FR). The results were analyzed using analysis of variance (ANOVA) and Tukey's multiple comparison test to detect significant differences. Two dendrograms among isolates were obtained with UPGMA using the Euclidean distance index. One was drawn for phenotypic data, and the other for phenotypic and genotypic data. A PCoA was done for shown isolates in a space of reduced dimensionality. In order to determine the degree of association between the phenotypic and genotypic characteristics AFLP, we calculated the correlation between parwise Euclidean distance matrices of both data sets with the nonparametric Mantel test. RESULTS: No variability was found in the macromorphology of the studied isolates; however, the micromorphology and growth rate showed that the PE isolates grew at a faster rate and exhibited the widest vesicles in comparison to the isolates from MX, AR and FR. The dendrogram constructed with phenotypic data showed three distinct groups. The group I and II were formed with isolates from PE and FR, respectively, while group III was formed with isolates from MX and AR. The dendrogram with phenotypic and genotypic data showed the same cluster, except for an isolate from FR that formed a separate cluster. This cluster was confirmed using PCoA. The correlation between the phenotypic and genotypic data of the isolates revealed a statistically significant association between these characteristics. CONCLUSIONS: The PE isolates showed specific phenotypic characteristics that clearly differentiate them from the rest of the isolates, which matches the genotypic data. The correlation between the phenotypic and genotypic characteristics showed a statistically significant association. In conclusion, phenotypic and genotypic methods together increase the power of correlation between isolates.

Molecular findings of disseminated histoplasmosis in two captive snow leopards (Uncia uncia).

This paper reports two cases of disseminated histoplasmosis in captive snow leopards (Uncia uncia). Histoplasmosis was diagnosed based on histopathology, immunohistochemistry, transmission electron microscopy, and molecular findings.

Geographical distribution of genetic polymorphism of the pathogen Histoplasma capsulatum isolated from infected bats, captured in a central zone of Mexico.

Fourteen Histoplasma capsulatum isolates recovered from infected bats captured in Mexican caves and two human H. capsulatum reference strains were analyzed using random amplification of polymorphic DNA PCR-based and partial DNA sequences of four genes. Cluster analysis of random amplification of polymorphic DNA-patterns revealed differences for two H. capsulatum isolates of one migratory bat Tadarida brasiliensis. Three groups were identified by distance and maximum-parsimony analyses of arf, H-anti, ole, and tub1 H. capsulatum genes. Group I included most isolates from infected bats and one clinical strain from central Mexico; group II included the two isolates from T. brasiliensis; the human G-217B reference strain from USA formed an independent group III. Isolates from group II showed diversity in relation to groups I and III, suggesting a different H. capsulatum population.

Identification of the infectious source of an unusual outbreak of histoplasmosis, in a hotel in Acapulco, state of Guerrero, Mexico.

Three isolates of Histoplasma capsulatum were identified from mice lung, liver, and spleen inoculated with soil samples of the X hotel's ornamental potted plants that had been fertilized with organic material known as compost. The presence of H. capsulatum in the original compost was detected using the dot-enzyme-linked immunosorbent assay. Nested-PCR, using a specific protein Hcp100 coding gene sequence, confirmed the fungal identification associated with an unusual histoplasmosis outbreak in Acapulco. Although, diversity between the H. capsulatum isolate from the hotel and some clinical isolates from Guerrero (positive controls) was observed using random amplification of polymorphic DNA based-PCR, sequence analyses of H-anti and ole fragment genes revealed a high homology (92-99%) between them.

Phenotyping and genotyping of Sporothrix schenckii isolates according to geographic origin and clinical form of Sporotrichosis.

Sporothrix schenckii isolates of fixed and lymphocutaneous clinical forms from Mexico (MX), Guatemala (GT), and Colombia (CO) as well as environmental isolates from MX were studied by analyzing their phenotypic characteristics (conidial length, thermotolerance by percent growth inhibition [GI] at 35 and 37 degrees C, median lethal dose [LD(50)]) and genotypic characteristics (by random amplified polymorphic DNA [RAPD] analysis-PCR). A significant difference (P < 0.01) in the mean conidial length of S. schenckii clinical isolates from CO ( = 4.03 +/- 1.04 microm) compared with those of clinical isolates from MX ( = 2.06 +/- 0.53 microm) and GT ( = 2.68 +/- 0.83 microm) was observed. The lowest thermotolerance, as determined by measurement of percent GI, was exhibited by isolates from CO at 35 degrees C ( = 50.1% +/- 15.9%) and 37 degrees C ( = 72.7% +/- 10.9%). In general, the highest virulence, as determined by measurement of the LD(50) for mice, was observed for the MX environmental isolates. RAPD analysis-PCR with 10-mer primers OPBG-01, OPBG-14, and OPBG-19 generated 52 reproducible bands. The 44 Sporothrix isolates fell into four major groups by hierarchical cluster analysis. The first group (group I), formed by 25 (of 27) isolates from MX, had two subgroups: subgroup Ia with 10 environmental isolates and subgroup Ib with 14 clinical isolates. The second group (group II) had two subgroups: subgroup IIa, formed by isolates from CO, and subgroup IIb, formed by isolates from GT. Groups III and IV each had only one clinical isolate from MX. A principal-component analysis of the same data yielded three distinct groups, depending on the geographical origins of the isolates, including the isolates in groups III and IV from MX, which were grouped with the isolates from MX by principal-component analysis. This study revealed that isolates from CO had low thermotolerances at 35 and 37 degrees C and could be associated with superficial skin lesions in patients with fixed clinical forms of sporotrichosis, the most frequent form of the disease in CO. Distinct patterns dependent on geographical origins were also revealed by RAPD analysis-PCR, but these had no relation to the clinical form of the disease.