Search

Sporotrichosis is a subcutaneous infection caused by fungi from the genus Sporothrix. It is transmitted by inoculation of infective particles found in plant-contaminated material or diseased animals, characterizing the classic sapronotic and emerging zoonotic transmission, respectively. Since 1998, southeastern Brazil has experienced a zoonotic sporotrichosis epidemic caused by S. brasiliensis, centred in the state of Rio de Janeiro. Our observation of feline sporotrichosis cases in Brasília (Midwestern Brazil), around 900 km away from Rio de Janeiro, led us to question whether the epidemic caused by S. brasiliensis has spread from the epicentre in Rio de Janeiro, emerged independently in the two locations, or if the disease has been present and unrecognized in Midwestern Brazil. A retrospective analysis of 91 human and 4 animal cases from Brasília, ranging from 1993 to 2018, suggests the occurrence of both sapronotic and zoonotic transmission. Molecular typing of the calmodulin locus identified S. schenckii as the agent in two animals and all seven human patients from which we were able to recover clinical isolates. In two other animals, the disease was caused by S. brasiliensis. Whole-genome sequence typing of seven Sporothrix spp. strains from Brasília and Rio de Janeiro suggests that S. brasiliensis isolates from Brasília are genetically distinct from those obtained at the epicentre of the outbreak in Rio de Janeiro, both in phylogenomic and population genomic analyses. The two S. brasiliensis populations seem to have separated between 2.2 and 3.1 million years ago, indicating independent outbreaks or that the zoonotic S. brasiliensis outbreak might have started earlier and be more widespread in South America than previously recognized.

Sporotrichosis is a subcutaneous infection caused by fungi from the genus Sporothrix. It is transmitted by inoculation of infective particles found in plant-contaminated material or diseased animals, characterizing the classic sapronotic and emerging zoonotic transmission, respectively. Since 1998, southeastern Brazil has experienced a zoonotic sporotrichosis epidemic caused by S. brasiliensis, centred in the state of Rio de Janeiro. Our observation of feline sporotrichosis cases in Brasília (Midwestern Brazil), around 900 km away from Rio de Janeiro, led us to question whether the epidemic caused by S. brasiliensis has spread from the epicentre in Rio de Janeiro, emerged independently in the two locations, or if the disease has been present and unrecognized in Midwestern Brazil. A retrospective analysis of 91 human and 4 animal cases from Brasília, ranging from 1993 to 2018, suggests the occurrence of both sapronotic and zoonotic transmission. Molecular typing of the calmodulin locus identified S. schenckii as the agent in two animals and all seven human patients from which we were able to recover clinical isolates. In two other animals, the disease was caused by S. brasiliensis. Whole-genome sequence typing of seven Sporothrix spp. strains from Brasília and Rio de Janeiro suggests that S. brasiliensis isolates from Brasília are genetically distinct from those obtained at the epicentre of the outbreak in Rio de Janeiro, both in phylogenomic and population genomic analyses. The two S. brasiliensis populations seem to have separated between 2.2 and 3.1 million years ago, indicating independent outbreaks or that the zoonotic S. brasiliensis outbreak might have started earlier and be more widespread in South America than previously recognized.

Background: Paracoccidioidomycosis (PCM) and histoplasmosis are endemic fungal diseases in South America. Both can lead to lung involvement with fungal dissemination progressing to systemic and severe clinical manifestations, especially in immunosuppressed hosts. As the population of immunosuppressed individuals has been rising, a higher occurrence of fungal infections is predicted in this setting. This poses challenges regarding the differential diagnosis due to overlapping clinical and laboratorial findings, hampering the management of cases. Objectives: In this study, the authors discuss the occurrence of a false-positive Histoplasma urinary antigen detection in a kidney transplant recipient with acute PCM. Given the scarce information about this subject, a review on literature data is provided. Methods: A comprehensive literature search was conducted to investigate previous studies that found cross-reactivity between Histoplasma urinary antigen assays in human patients with confirmed diagnosis of PCM. Additionally, an update of PCM in transplant recipients is provided. Findings: The included studies reported 120 samples from patients with PCM tested for Histoplasma antigen, presenting an overall cross-reactivity of 51.67% and 17 cases of PCM in transplant recipients. CONCLUSIONS: The galactomannan urinary antigen developed to diagnose histoplasmosis can cross react with PCM, which may represent a concern in countries where both mycoses overlap. Author summary: Paracoccidioidomycosis (PCM) and histoplasmosis are severe fungal diseases occurring simultaneously in South America. They can cause similar clinical manifestations, especially in immunosuppressed hosts. This poses challenges regarding the differential diagnosis due to overlapping clinical and laboratorial findings, hampering the management of individual cases. In this study, the authors report the occurrence of a false-positive urinary test to detect histoplasmosis in a kidney transplant recipient with acute PCM. Given the scarce information about this subject, a review on literature data is provided. As conclusion, this study highlights the urinary test developed to diagnose histoplasmosis can cross react with PCM, which may represent a concern in countries where both mycoses overlap. [ABSTRACT FROM AUTHOR]

During the infectious process, pathogenic microorganisms must obtain nutrients from the host in order to survive and proliferate. These nutritional sources include the metallic nutrient copper. Despite its essentiality, copper in large amounts is toxic. Host defense mechanisms use high copper poisoning as a fungicidal strategy to control infection. Transcriptional analyses showed that yeast cultured in the presence of copper or inside macrophages (24 h) had elevated expression of CRP1, a copper efflux pump, suggesting that Histoplasma capsulatum could be exposed to a high copper environment in macrophages during the innate immune stage of infection. Accordingly, macrophages cultured in high copper are more efficient in controlling H. capsulatum growth. Also, silencing of ATP7a, a copper pump that promotes the copper influx in phagosomes, increases fungal survival in macrophages. The rich copper environment faced by the fungus is not dependent on IFN‐γ, since fungal CRP1 expression is induced in untreated macrophages. Appropriately, CRP1 knockdown fungal strains are more susceptible to macrophage control than wild‐type yeasts. Additionally, CRP1 silencing decreases fungal burden in mice during the phase of innate immune response (4‐day postinfection) and CRP1 is required for full virulence in a macrophage cell lines (J774 A.1 and RAW 264.7), as well as primary cells (BMDM). Thus, induction of fungal copper detoxifying genes during innate immunity and the attenuated virulence of CRP1‐knockdown yeasts suggest that H. capsulatum is exposed to a copper‐rich environment at early infection, but circumvents this condition to establish infection. [ABSTRACT FROM AUTHOR]

Background: Sporotrichosis is a subcutaneous or implantation mycosis caused by some species of the genus Sporothrix. Rio de Janeiro state, Brazil, experiences hyperendemic levels of zoonotic sporotrichosis, with increasing cases of disseminated disease, especially in people living with HIV (PLHIV). Involvement of the nasal mucosa is rare and occurs isolated or in disseminated cases, with a delayed resolution. Methodology/Principal findings: This study aimed to describe the epidemiological, clinical, and therapeutic profiles of 37 cases of sporotrichosis with involvement of the nasal mucosa treated at the ear, nose, and throat (ENT) outpatient clinic of the Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, from 1998 to 2020. Data were reviewed from the medical records and stored in a database. The Mann–Whitney test was used to compare the means of quantitative variables, and Pearson chi-square and Fisher's exact tests were used to verify the association between qualitative variables (p<0.05). Most patients were males, students or retirees, with a median age of 38 years, residents in the municipality of Rio de Janeiro, and infected through zoonotic transmission. Disseminated sporotrichosis forms in patients with comorbidities (mostly PLHIV) were more common than the isolated involvement of the mucosa. The main characteristics of lesions in the nasal mucosa were the presence/elimination of crusts, involvement of various structures, mixed appearance, and severe intensity. Due to therapeutic difficulty, itraconazole was combined with amphotericin B and/or terbinafine in most cases. Of the 37 patients, 24 (64.9%) healed, with a median of 61 weeks of treatment, 9 lost follow-up, 2 were still treating and 2 died. Conclusions: Immunosuppression was determinant to the outcome, with worse prognosis and lower probability of cure. Notably in this group, the systematization of the ENT examination for early identification of lesions is recommended to optimize the treatment and outcome of the disease. Author summary: Sporotrichosis is a subcutaneous or implantation mycosis with hyperendemic levels of zoonotic transmission in Rio de Janeiro state, Brazil. The involvement of the nasal mucosa is uncommon and may occur in isolated or disseminated forms of sporotrichosis, but the number of cases has been increasing. We analyzed 37 cases of sporotrichosis with involvement of the nasal mucosa treated at a reference center for infectious diseases. There was a predominance of males, students and retirees, residents in the municipality of Rio de Janeiro, and infected by cats. The median age was 38 years. Disseminated forms of sporotrichosis predominated over isolated involvement of the nasal mucosa. The number of patients with HIV infection also caught our attention. The main characteristics of the nasal mucosa lesions were the presence/elimination of crusts, with an involvement of various structures. Most cases were treated with a combination of antifungal agents and were cured, and two deaths were observed. Immunosuppression directly influenced the prognosis of cure of nasal mucosa sporotrichosis. [ABSTRACT FROM AUTHOR]

Histoplasmosis is a frequent mycosis in people living with HIV/AIDS and other immunocompromised hosts. Histoplasmosis has high rates of mortality in these patients if treatment is unsuccessful. Itraconazole and amphotericin B are used to treat histoplasmosis; however, both antifungals have potentially severe pharmacokinetic drug interactions and toxicity. The present study determined the minimal inhibitory and fungicidal concentrations of mebendazole, a drug present in the NIH Clinical Collection, to establish whether it has fungicidal or fungistatic activity against Histoplasma capsulatum. Protein extracts from H. capsulatum yeasts, treated or not with mebendazole, were analyzed by proteomics to understand the metabolic changes driven by this benzimidazole. Mebendazole inhibited the growth of 10 H. capsulatum strains, presenting minimal inhibitory concentrations ranging from 5.0 to 0.08 µM. Proteomics revealed 30 and 18 proteins exclusively detected in untreated and mebendazole-treated H. capsulatum yeast cells, respectively. Proteins related to the tricarboxylic acid cycle, cytoskeleton, and ribosomes were highly abundant in untreated cells. Proteins related to the nitrogen, sulfur, and pyrimidine metabolisms were enriched in mebendazole-treated cells. Furthermore, mebendazole was able to inhibit the oxidative metabolism, disrupt the cytoskeleton, and decrease ribosomal proteins in H. capsulatum. These results suggest mebendazole as a drug to be repurposed for histoplasmosis treatment. [ABSTRACT FROM AUTHOR]

Itraconazole is the first choice for treating sporotrichosis. Amphotericin B is indicated for severe and disseminated forms. The aim of the study was to evaluate the antifungal susceptibility of Sporothrix brasiliensis strains isolated from patients with severe sporotrichosis treated with amphotericin B and correlate with clinical outcomes. Clinical and epidemiological data were obtained from severe sporotrichosis cases caused by S. brasiliensis. Antifungal susceptibility tests against amphotericin B, itraconazole, terbinafine, posaconazole, and 5-flucytosine were performed. Moreover, possible synergisms between amphotericin B and posaconazole or 5-flucytosine were assessed. Relationships between clinical and laboratorial data were then analyzed. Forty-six S. brasiliensis isolates from 37 patients were studied. Clinical forms included disseminated (94.6%) and disseminated cutaneous sporotrichosis (5.4%). The median treatment time was 784 days (range: 7 to 3115 days). Cure occurred in 45.9% of the cases and death due to sporotrichosis in 24.3%. Forty-three (93.5%) S. brasiliensis isolates were classified as wild-type for all the antifungals tested according to their in vitro antifungal susceptibility. There was no synergism for the combinations studied. Finally, we found no association between higher Minimal Inhibitory Concentration (MIC) values of amphotericin B or itraconazole with unfavorable outcomes; however, there were higher MIC values of itraconazole in strains isolated from alcoholic patients. Possibly, clinical factors, such as the extent of dissemination, immunosuppression, and late treatment onset, are the main determinants of patient outcomes, rather than antifungal resistance. The current study suggests that the need to use amphotericin B therapy is not associated with the emergence of S. brasiliensis resistant strains. [ABSTRACT FROM AUTHOR]

Sporotrichosis is a subcutaneous mycosis with worldwide distribution and caused by eight pathogenic species of the Sporothrix genus. Different ex situ preservation methods are used around the world to maintain the survival, morphophysiological and genetic traits of fungal strains isolated from patients with sporotrichosis for long terms. The main aim of the present study was to evaluate the survival, phenotypic and genotypic stability of Sporothrix strains after preservation on PDA slant stored at 4 °C, sterile water and cryopreservation at −80 °C, for a period of time of 6, 12, 18 and 24 months of storage. Eight clinical Sporothrix isolates were identified based on a polyphasic approach consisting of classical macro- and micro-morphological traits, biochemical assays, proteomic profiles by MALDI-TOF MS and molecular biology. According to the final identification, one strain was identified as S. schenckii (CMRVS 40428) and seven strains were re-identified as S. brasiliensis (CMRVS 40421, CMRVS 40423, CMRVS 40424, CMRVS 40425, CMRVS 40426, CMRVS 40427 and CMRVS 40433). In addition, it was observed that the isolates survived after the different time points of storage in distilled water, PDA slant and cryopreservation at −80 °C. For fungi preserved in water, low polymorphisms were detected by the partial sequencing of β-tubulin. Cryopreservation at −80 °C induced morphological changes in one single isolate. The proteomic profiles obtained by MALDI-TOF MS after preservation showed differences among the methods. In conclusion, preservation on agar slant stored at 4 °C was the most effective method to preserve the eight clinical Sporothrix strains. This method produced less change in the phenotypic traits and kept the genetic integrity of all strains. Agar slant stored at 4 °C is a simple and inexpensive method and can be especially used in culture collections of limited funding and resources. [ABSTRACT FROM AUTHOR]

Meningeal sporotrichosis is rare and occurs predominantly in immunosuppressed individuals. This retrospective study explored clinical and laboratory characteristics, treatment, and prognosis of patients with disseminated sporotrichosis who underwent lumbar puncture (LP) at a Brazilian reference center from 1999 to 2020. Kaplan–Meier and Cox regression models were used to estimate overall survival and hazard ratios. Among 57 enrolled patients, 17 had meningitis. Fifteen (88.2%) had HIV infection, and in 6 of them, neurological manifestations occurred because of the immune reconstitution inflammatory syndrome (IRIS). The most frequent symptom was headache (88.2%). Meningeal symptoms at first LP were absent in 7/17 (41.2%) patients. Sporothrix was diagnosed in cerebrospinal fluid either by culture or by polymerase chain reaction in seven and four patients, respectively. All but one patient received prolonged courses of amphotericin B formulations, and seven received posaconazole, but relapses were frequent. Lethality among patients with meningitis was 64.7%, with a higher chance of death compared to those without meningitis (HR = 3.87; IC95% = 1.23;12.17). Meningeal sporotrichosis occurs mostly in people with HIV and can be associated with IRIS. Screening LP is indicated in patients with disseminated disease despite the absence of neurological complaints. Meningitis is associated with poor prognosis, and better treatment strategies are needed. [ABSTRACT FROM AUTHOR]