Optimization of a commercial Histoplasma galactomannan EIA test in a population from an endemic area of histoplasmosis in southern Brazil.

BACKGROUND: Since 2020 the World Health Organization (WHO) recommends Histoplasma antigen detection for the diagnosis of disseminated histoplasmosis (DH) in people living with HIV (PLHIV). OBJECTIVE: Here we aimed to optimise the IMMY's Clarus® Histoplasma GM enzyme immunoassay (EIA), evaluating the best cut-off in the semi-quantitative (SQ-HGM EIA), also known as 'calibrator cut-off procedure'. METHODS: The optimization was done using the quantitative standard procedure (Q-HGM EIA), also known as 'standard curve procedure', as reference test. A retrospective study from an endemic area of DH in southern Brazil was carried out including 264 patients investigated for DH using the test. Receiver Operator Characteristic curve was plotted, and sensitivity and specificity of the SQ-HGM EIA were calculated. RESULTS: The study included 24 positive (values ≥ 0.20 ng/ml) and 240 negative patients by the Q-HGM EIA. According to the manufacturer SQ-HGM EIA protocol, the new SQ-HGM EIA cut-off of 0.8 EIA units was validated, resulting in sensitivity and specificity of 88% and 98.7%, respectively. CONCLUSION: Our study pioneers and brings important data about the optimization of the Histoplasma antigen testing for the diagnosis of DH in a population from Southern Brazil. This optimization also reduced the amount of reagents used, lowering the cost associated with testing.

Anti-Aspergillus fumigatus IgG in patients with bronchiectasis and its relationship with clinical outcome.

Aspergillosis is a mycosis, most commonly affecting the airways. This mycosis can worsen the clinical condition of patients with concurrent lung diseases. We assayed for the presence of serum anti-A. fumigatus IgG in bronchiectasis patients from a tertiary hospital in south Brazil and evaluated the relationship with clinical outcome. Thirty-one patients with bronchiectasis, without cystic fibrosis, were included. Clinical and epidemiological data were collected from all participants. Positive serological tests were detected in 13% (4/31) of the patients. The mortality rate for the year following the assay was, in the seropositive group, 75% (3/4), whereas in the seronegative group, 15% (4/27). An illustrative case is also shown and discussed. Our study highlights the diagnostic challenge and the possible impact of Aspergillus infection on these patients, indicating the necessity of more and larger investigations in the field.

In vitro susceptibility of Sporothrix spp. to complexes coordinated with Co(II) and cobalt chloride hexahydrate

Abstract Sporothrix spp. are the major dimorphic fungus associated with a type of subcutaneous mycosis, sporotrichosis. The limitation of antifungal availability and the past reports of in vitro resistance of Sporothrix spp. clinical isolates makes it important to search for new compounds with antifungal activities. In this study, we therefore evaluate the in vitro activities of complexes coordinated with Co(II) and cobalt chloride hexahydrate against clinical isolates of Sporothrix spp. Broth microdilution test was performed as per M38-A2 from CLSI (2008) in duplicate for 31 clinical isolates of Sporothrix spp. (27 S. brasiliensis e 04 S. schenckii stricto sensu). The antifungal activities of the complexes coordinated with Co(II) and cobalt chloride hexahydrate were detected at a concentration range of 32-128 µg/mL for all isolates. None of the compounds demonstrated any cytotoxicity (to macrophage cells) at the concentration of 200 µg/mL. The activity against Sporothrix spp. recorded in this study instigate the continuity of experimental studies with Co(II) to search for the mechanisms of antifungal action as well as to evaluate its interaction with the commercial antifungal drugs.

Disseminated sporotrichosis with immune reconstitution inflammatory syndrome in an HIV patient: Case report and review of the literature.

BACKGROUND: Sporotrichosis has been occurring as outbreaks in Brazil, reaching epidemic levels in some regions. Zoonotic transmission is the main route to acquire Sporothrix. CASE REPORT: We describe a case of disseminated sporotrichosis caused by Sporothrix brasiliensis in an HIV/AIDS patient, with the presentation of immune reconstitution inflammatory syndrome (IRIS). CONCLUSIONS: This case reinforces that sporotrichosis should always be suspected in patients with IRIS from endemic regions, even in patients without the typical cutaneous lesions of this mycosis.

Disseminated sporotrichosis with immune reconstitution inflammatory syndrome in an HIV patient: case report and review of the literature / Esporotricosis diseminada y síndrome inflamatorio de reconstitución inmune en un paciente con VIH: reporte de un caso y revisión de la literatura

BACKGROUND: Sporotrichosis has been occurring as outbreaks in Brazil, reaching epidemic levels in some regions. Zoonotic transmission is the main route to acquire Sporothrix. CASE REPORT: We describe a case of disseminated sporotrichosis caused by Sporothrix brasiliensis in an HIV/AIDS patient, with the presentation of immune reconstitution inflammatory syndrome (IRIS). CONCLUSIONS: This case reinforces that sporotrichosis should always be suspected in patients with IRIS from endemic regions, even in patients without the typical cutaneous lesions of this mycosis

ANTECEDENTES: La esporotricosis suele aparecer en Brasil en forma de brotes y alcanza tasas epidémicas en algunas regiones. La ruta principal de transmisión es la zoonótica. CASO CLÍNICO: Describimos un caso de esporotricosis diseminada causado por Sporothrix brasiliensis en una paciente con VIH/sida que presentó un síndrome inflamatorio de reconstitución inmune (SIRI). CONCLUSIONES: Este caso demuestra que en regiones endémicas de esporotricosis esta micosis siempre debe ser sospechada en casos de SIRI, incluso en pacientes sin las lesiones cutáneas típicas de esta enfermedad

Antifungal activity of diphenyl diselenide alone and in combination with itraconazole against Sporothrix brasiliensis.

Sporothrix brasiliensis is the main agent of feline and zoonotic sporotrichosis. Given the scarcity of options for sporotrichosis treatment and the promising activity of diphenyl diselenide (PhSe)2 against a diversity of fungal pathogens, this study aimed to evaluate the in vitro susceptibility of Sporothrix brasiliensis to (PhSe)2 alone and in combination with itraconazole (ITC). Forty clinical isolates of S. brasiliensis were subjected to broth microdilution method to evaluate their susceptibility to (PhSe)2 in concentrations ranging between 0.25 and 128 µg/ml, and to ITC (0.0313-16 µg/ml) following the protocol of the Clinical and Laboratory Standards Institute (CLSI, 2008). All of these isolates were also used to evaluate the interaction between these drugs by checkerboard technique. Geometric mean of (PhSe)2 MIC values was 12.12 µg/ml, ranging from 4 to 32 µg/ml, and for ITC was 0.37 µg/ml (0.125 to 1 µg/ml). Benefic effect (additive or synergistic) in the interaction test between (PhSe)2 and ITC occurs in 73% (29/40) of the isolates. The promising (PhSe)2in vitro activity against S. brasiliensis suggests that it may not only be a potential alternative therapy but also be used as a combination with ITC, which is the first choice of therapy to sporotrichosis.

Human sporotrichosis: A zoonotic outbreak in southern Brazil, 2012-2017.

Zoonotic sporotrichosis has undergone a geographical expansion in Brazil in the last decade. Rio Grande do Sul (RS) is the second state of the country in which a number of feline sporotrichosis cases have been described. Since cats are the main zoonotic source of infection, this study aimed to describe 100 cases of human sporotrichosis occurring in the last 5 years in the southern region of RS, Brazil. In addition, we aimed to illustrate the zoonotic importance of the disease, describing four cases in the same family due to transmission by their cat. This great number of human cases in a short period of evaluation highlights the severity of sporotrichosis as a public health problem in the region, suggesting that a possible outbreak is occurring that requires immediate public intervention actions to weaken its impact.

Sporotrichosis in Southern Brazil, towards an epidemic?

Rio Grande do Sul (RS) is the second highest state with respect to sporotrichosis incidence in Brazil, with most cases occurring in the southern region. Given the importance of epidemiologic monitoring in hyperendemic areas, this study evaluated the spatial, geographical and annual sporotrichosis incidence over a period of 7 years in the southern region of RS, as well as the disease evolution over the last two decades. Data were collected from the Mycology Laboratory of the Federal University of Rio Grande (FAMED-FURG) and from the Centre for Zoonosis Control (CZC) of the Prefeitura Municipal of Pelotas city. All feline cases of sporotrichosis diagnosed between 2010 and 2016 were included and analysed. In addition, cases of human and canine sporotrichosis were accounted for. Over the 7-year period (2010-2016), 372 feline, 34 canine and 83 human cases of sporotrichosis were diagnosed, being the mean number of cases/year 18.33 in the first 3 years of the study and 116.33 in the last 3 years. Cases were distributed among 34 and 28 neighbourhoods in Rio Grande and Pelotas city, respectively. Socioeconomic features reinforced the result that the disease is already spreading across a major part of the southern region. In addition, the study demonstrated the intensification and expansion of the high endemicity areas. Therefore, given that the number of feline sporotrichosis cases in southern RS reached alarming proportions, we suggested that this region will promptly face an epidemic of sporotrichosis if no preventive or control measures are undertaken.

In vitro susceptibility of Sporothrix brasiliensis: Comparison of yeast and mycelial phases.

Sporothrix brasiliensis has emerged as an important cause of sporotrichosis, particularly associated with feline and zoonotic cases. Owing to the paucity of data on antifungal activity against this species, the present study aimed to evaluate the in vitro susceptibility of clinical isolates of S. brasiliensis in the mycelial and yeast phases to itraconazole (ITZ), terbinafine (TRB), and amphotericin B (AMB). Thirty-five isolates from an outbreak of feline sporotrichosis in Southern Brazil were used. All of them were assessed in the yeast and filamentous phases using the broth microdilution technique in accordance with the respective reference protocols M27-A3 and M38-A2 of the Clinical and Laboratory Standards Institute (CLSI). In our study, TRB was the most active antifungal against both the filamentous and yeast phases, showing GM of the MIC of 0.343 µg/ml and 0.127 µg/ml, respectively. In the yeast phase, the GM of the MIC for TRB was significantly lower than that for both ITZ (P = .009) and AMB (P < .001). However, in the filamentous phase, the GM of the MIC for TRB was significantly lower than that of AMB (P < .001), but not different from that of ITZ (P = .091). AMB was the antifungal with the highest GM of the MIC for both phases (1.486 µg/ml for the filamentous phase and 0.660 µg/ml for the yeast). Our results may contribute to a better understanding of antifungal susceptibility profiles of clinical isolates of S. brasiliensis in the mycelial and yeast phases in further studies.

Sporothrix brasiliensis outbreaks and the rapid emergence of feline sporotrichosis.

Sporotrichosis is the main subcutaneous mycosis in Brazil, and is caused by Sporothrix schenckii and allied species. Sporothrix propagules present on soil and plant debris may be traumatically inoculated into the cutaneous/ subcutaneous tissues of the warm-blooded host. An alternative route involves direct animal-animal and animal-human transmissions through deep scratches and bites of diseased cats. Sporotrichosis is much more common than previously appreciated with several cases emerging over the years especially in South and Southeast Brazil. We conducted an epidemiological surveillance in endemic areas of feline sporotrichosis in the southern region of Rio Grande do Sul state, Brazil. Over the last 5-year period the number of feline sporotrichosis in Rio Grande increased from 0.75 new cases per month in 2010 to 3.33 cases per month in 2014. The wide geographic distribution of diagnosed cases highlights the dynamics of Sporothrix transmission across urban areas with high population density. Molecular identification down to species level by PCR-RFLP of cat-transmitted Sporothrix revealed the emergence of the clonal offshoot S. brasiliensis during feline outbreaks; this scenario is similar to the epidemics taking place in the metropolitan areas of Rio de Janeiro and São Paulo. Controlling and preventing sporotrichosis outbreaks are essential steps to managing the disease among humans and animals.