Effectiveness of diphenyl diselenide against experimental sporotrichosis caused by Sporothrix brasiliensis.

Diphenyl diselenide (PhSe)2 is a stable organoselenium compound with promising in vitro antifungal activity against several fungi, including Sporothrix brasiliensis. This species is associated with feline and zoonotic sporotrichosis, an emergent mycosis in Latin America. We evaluated the activity of (PhSe)2, alone and in association with itraconazole, in the treatment of sporotrichosis caused by S. brasiliensis, in a murine model. Sixty mice were subcutaneously infected with S. brasiliensis in the footpad and treated by gavage for 30 consecutive days. The six treatment groups received: no active treatment, itraconazole (50 mg/kg), (PhSe)2 at 1, 5, and 10 mg/kg dosages, or itraconazole (50 mg/kg) + (PhSe)2 1 mg/kg, once a day, starting seven days post-inoculation. A significant reduction in the fungal burden of internal organs was achieved in the groups treated with (PhSe)2 1 mg/kg or itraconazole alone in comparison with the untreated group. Higher dosages (5 and 10 mg/kg) of (PhSe)2 increased the clinical manifestation of sporotrichosis and mortality rate. Treatment with both itraconazole and (PhSe)2 1 mg/kg was better than their activities alone (P < .001). This is the first demonstration of the potential use of (PhSe)2, alone or with the present drug of choice, in the treatment of sporotrichosis.

We evaluated the activity of diphenyl diselenide (PhSe)2, alone and in association with itraconazole, in the treatment of sporotrichosis caused by S. brasiliensis, in a murine model. This is the first demonstration of the potential use of (PhSe)2, alone or in an association against sporotrichosis.

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.

Disseminated Histoplasmosis in Persons with HIV/AIDS, Southern Brazil, 2010-2019.

We evaluated disseminated histoplasmosis (DH) in HIV patients over 10 years in southern Brazil. The incidence was 12 cases/1,000 hospitalizations (2010-2019); the mortality rate was 35%. Tuberculosis frequently obscured the diagnosis of DH. We emphasize the need in our region to suspect and investigate DH using more sensitive methods.

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.

CATastrophe: Response to the challenges of zoonotic sporotrichosis in southern Brazil.

BACKGROUND: In Brazil, zoonotic sporotrichosis became a national public health problem, with thousands of cases in the last decade in several regions of the country. In this context, health education activities are critical, especially in promoting early diagnosis and access to proper health care in sporotrichosis hyperendemic areas. Therefore, we report the implementation of a public specialised reference service (SRS) for diagnosis and treatment of sporotrichosis in southern Brazil. We evaluated the impact of the SRS on diagnostic confirmation and speed of diagnosis. METHODS: The SRS was implemented in Rio Grande City. We implemented a public service to promote the correct diagnosis, treatment and follow-up of human sporotrichosis cases. To study the impact of implementing SRS, the annual number of cases and the period between the appearance of lesions until diagnosis were compared, using prior data and that post-implementation. RESULTS: The implementation of the SRS directly benefited almost 50 patients in only four years, with the collaboration of almost 50% of the local health groups, together with an increase of more than 200% in diagnosis confirmation and speed of diagnosis, showing the reach, impact and importance of the SRS. CONCLUSION: The impact on the individual and collective health of the local population highlights the value of this public health approach in facing the epidemiological threat of zoonotic sporotrichosis.

Update of the Epidemiology of the Sporotrichosis Epidemic in the state of Rio Grande do Sul, Brazil.

BACKGROUND: Sporotrichosis is a disease not requiring jurisdictional notification and consequently is underreported in Brazil. Therefore, the epidemiological picture even in hyperendemic states is unknown. Thus, we evaluated the occurrence of sporotrichosis throughout the territory of the southern state of Brazil, Rio Grande do Sul (RS). METHODS: We update the epidemiological situation of sporotrichosis in the southern region of this state and describe the emergence of this disease in the Metropolitan region. We engaged professionals from RS enrolled in animal health care in answering a questionnaire regarding sporotrichosis. RESULTS: The occurrence of local cases of feline sporotrichosis was reported by 83% of the participants from 40 cities, distributed through the seven health districts of RS. Human sporotrichosis cases, transmitted by cats, were also reported by professionals from four regions of the state. The frequency of the disease in both the South and Metropolitan regions showed a marked increase in recent years. CONCLUSION: Feline and cat-transmitted human sporotrichosis is an underreported mycosis in RS, widely distributed in the territory of this state and increasing. Aggressive public health policies are urgently necessary to control the geographical expansion of this spreading mycosis.

Fungal Bloodstream Co-infection by Trichosporon asahii in a COVID-19 Critical Patient: Case Report and Literature Review.

Opportunistic infections are serious complications in critically ill COVID-19 patients, especially co-infections with bacterial and fungal agents. Here we report a rare case of bloodstream co-infection by Trichosporon asahii, an emerging yeast, and Acinetobacterbaumannii, an opportunistic nosocomial pathogen, both multidrug resistant, in a tertiary hospital from southern Brazil. A review of the literature regarding similar cases is also included. Treatment with multiple antimicrobials failed, and the patient progressed to death four days after the diagnosis of bacteremia and fungemia.

Ebselen and diphenyl diselenide against fungal pathogens: A systematic review.

Fungal infections are one of the most prevalent diseases in the world and there is a lack of new antifungal drug development for these diseases. We conducted a systematic review of the literature regarding the in vitro antifungal activity of the organoselenium compounds ebselen (Eb) and diphenyl diselenide [(PhSe)2]. A systematic review was carried out based on the search for articles with data concerning Minimal Inhibitory Concentration (MIC) values, indexed in international databases and published until August 2020. A total of 2337 articles were found, and, according to the inclusion and exclusion criteria used, 22 articles were included in the study. Inhibitory activity against 96% (200/208) and 95% (312/328) of the pathogenic fungi tested was described for Eb and [(PhSe)2], respectively. Including in these 536 fungal isolates tested, organoselenium activity was highlighted against Candida spp., Cryptococcus ssp., Trichosporon spp., Aspergillus spp., Fusarium spp., Pythium spp., and Sporothrix spp., with MIC values lower than 64 µg/mL. In conclusion, Eb and [(PhSe)2] have a broad spectrum of in vitro inhibitory antifungal activity. These data added with other pharmacological properties of these organoselenium compounds suggest that both compounds are potential future antifungal drugs. Whether MICs toward the upper end of the ranges described here are compatible with efficacious therapy, and whether they may achieve such end as a result of the favorable non-antimicrobial effects of selenium on the host, requires more in vivo testing.

Fungal infections require the investigation of new drugs. The study is a systematic review of organo-selenium compounds with potential antifungal action. In 22 articles included in this review, in a total of 536 isolates of pathogenic fungi tested, the compounds showed action in more than 90% of them.

Synergism of Nikkomycin Z in Combination with Diphenyl Diselenide Against Sporothrix spp.

We evaluated the in vitro activity of nikkomycin Z (NikZ) in combination with diphenyl diselenide (PhSe)2, two compounds previously shown to have anti-Sporothrix spp. activity. Eighteen isolates of Sporothrix spp. were tested in checkerboard assays. Synergism for inhibition and killing Sporothrix spp. occurred in 100% and 89% of the isolates, respectively. The anti-Sporothrix spp. activity of this combination provides a rationale for in vivo studies to evaluate the application of both compounds in sporotrichosis treatment.

COVID-19-Associated Histoplasmosis in an AIDS Patient.

Most reports associating fungal infections with COVID-19 have been cases of invasive aspergillosis. Here, we report a case of severe histoplasmosis and COVID-19 infections in an HIV patient in Rio Grande, Southern Brazil. Histoplasmosis must be included as a diagnostic possibility in opportunistic fungal co-infections in COVID-19 patients with AIDS, mainly in endemic areas.

Association of NR1I2 gene polymorphisms and time of progression to AIDS.

BACKGROUND: The time of progression towards AIDS can vary greatly among seropositive patients, and may be associated with host genetic variation. The NR1I2 (PXR) gene, a ligand-activated transcription factor, regulates the transcription immune pathway genes and can therefore be targets of viral replication mechanisms influencing time of progression to AIDS. OBJECTIVE: To verify the association of single nucleotide polymorphisms (SNPs) rs3814057, rs6785049, rs7643645, and rs2461817 in the NR1I2 (PXR) gene with progression to AIDS in HIV-1 infected patients. METHODS: Blood samples were obtained from 96 HIV-1 positive individuals following informed consent. DNA was isolated and genotyped through real time polymerase chain reaction (PCR) for the presence of SNPs in the NR1I2. Questionnaires on socio-demographic features and behaviors were answered and time of progression to AIDS was estimated based on medical chart analysis. FINDINGS: Patients with the GG genotype for rs7643645 were shown to be related with a more rapid disease progression when compared to GA and AA genotypes. This result was maintained by the Multivariate Cox Regression considering sex, ethnicity, and presence of HLA-B*57, HLA-B*27, and CCR5del32 polymorphisms. MAIN CONCLUSIONS: Recent studies reported the expression of the nuclear receptors in T-Lymphocytes, suggesting their possible role in the immune response. In addition, nuclear receptors have been shown to inhibit the HIV replication, although no such mechanism has been thoroughly elucidated to date. This is the first time an association between NR1I2 polymorphism and time of progression to AIDS is reported and supports an apparent relationship between the gene in the immune response and identifies another genetic factor influencing AIDS progression.

Initial Results of the International Efforts in Screening New Agents against Candida auris.

BACKGROUND: Candida auris is an emergent fungal pathogen and a global concern, mostly due to its resistance to many currently available antifungal drugs. OBJECTIVE: Thus, in response to this challenge, we evaluated the in vitro activity of potential new drugs, diphenyl diselenide (PhSe)2 and nikkomycin Z (nikZ), alone and in association with currently available antifungals (azoles, echinocandins, and polyenes) against Candida auris. METHODS: Clinical isolates of C. auris were tested in vitro. (PhSe)2 and nikZ activities were tested alone and in combination with amphotericin B, fluconazole, or the echinocandins, micafungin and caspofungin. RESULTS: (PhSe)2 alone was unable to inhibit C. auris, and antagonism or indifferent effects were observed in the combination of this compound with the antifungals tested. NikZ appeared not active alone either, but frequently acted cooperatively with conventional antifungals. CONCLUSION: Our data show that (PhSe)2 appears to not have a good potential to be a candidate in the development of new drugs to treat C. auris, but that nikZ is worthy of further study.

Treatment of Human Sporotrichosis Caused by Sporothrix brasiliensis.

We describe the successful treatment of a series of 30 zoonotic sporotrichosis cases from southern Brazil. Sporothrix brasiliensis was the species genotypically identified in all 25 confirmed cases. Five other cases were classified as probable, without laboratory confirmation, but with clinical and epidemiological data of cat-transmitted sporotrichosis. Two isolates were sequenced by translation elongation factor-1 alpha (EF1α) loci in order to compare their sequences, and both of them showed distinct genotypes from S. brasiliensis strains from other Brazilian states. Itraconazole (ITZ) or potassium iodide (KI) were the first choice treatment in 28 and 2 cases, respectively. Microdilution assay showed a wild-type profile of S. brasiliensis isolates to ITZ. However, a lack of clinical response occurred in 42% of cases, especially those treated with ITZ 100 mg/day, and treatment needed modifications, by either increased doses or antifungal combinations. Clinical cure required a mean of 187 days of treatment, which was dependent on the clinical form of the disease and age of patients. Therapy, including dosages and durations, for cutaneous forms of sporotrichosis requires re-evaluation, since cases caused by S. brasiliensis may influence treatment efficacy.

In vitro anti-Cryptococcus activity of diphenyl diselenide alone and in combination with amphotericin B and fluconazole.

Cryptococcus is an encapsulated yeast that causes fungal meningitis, most commonly in HIV patients, with high mortality rates. Thus, the study of new treatment options is relevant. Antifungal activity of organoselenium compounds attributed to their pro-oxidative effect in fungal cells has been shown given that few data regarding its anti-Cryptococcus activity are available, this in vitro study was conducted with 40 clinical isolates of Cryptococcus neoformans. Diphenyl diselenide (DD) alone, and its interaction with amphotericin B or fluconazole, was tested by microdilution and checkerboard assays. All Cryptococcus neoformans were inhibited by DD in concentrations ≤ 32 µg/mL, and fungicidal concentrations were ≤ 64 µg/mL. Advantageous interaction between fluconazole occurred in 40% of the isolates, respectively. This study contributes with data of DD alone and in combination with classical drugs of choice for cryptococcosis treatment. Further studies focused on DD antifungal mechanism of action, and in vivo experiments are necessary.

Role of SEP15 Gene Polymorphisms in the Time of Progression to AIDS.

AIMS: HIV infection is a chronic disease that requires intensive treatment in its later phases, including dietary supplementation. Several studies have suggested clinical improvements in patients with high levels of selenium, linking these levels with a longer progression to AIDS. The objective of this study was to verify the association of two polymorphisms in the SEP15 gene, which encodes a selenoprotein that is responsible for the transport of selenium in cells, with the time of progression to AIDS in HIV-1-infected patients. METHODS: Blood samples were obtained from 139 HIV-1-positive individuals after they provided informed consent. DNA was isolated and genotyped using real-time polymerase chain reaction for the presence of SEP15 single nucleotide polymorphisms (rs5859 and rs561104). Questionnaires on sociodemographic features and behavior were answered, and the time of progression to AIDS was estimated based on a medical chart analysis. RESULTS: The allelic and genotypic frequencies did not differ between rapid and nonrapid progressors; however, the presence of the AA genotype of the rs5859 polymorphism was associated with a shorter time of progression to AIDS compared with GG homozygotes (hazard ratio = 3.62, 95% CI = 1.55-8.43, p = 0.003). CONCLUSION: These findings show the importance of genetic analysis of the SEP15 gene in individual patients with regard to predicting time of progression to AIDS.

Association of NR1I2 gene polymorphisms and time of progression to AIDS

BACKGROUND The time of progression towards AIDS can vary greatly among seropositive patients, and may be associated with host genetic variation. The NR1I2 (PXR) gene, a ligand-activated transcription factor, regulates the transcription immune pathway genes and can therefore be targets of viral replication mechanisms influencing time of progression to AIDS. OBJECTIVE To verify the association of single nucleotide polymorphisms (SNPs) rs3814057, rs6785049, rs7643645, and rs2461817 in the NR1I2 (PXR) gene with progression to AIDS in HIV-1 infected patients. METHODS Blood samples were obtained from 96 HIV-1 positive individuals following informed consent. DNA was isolated and genotyped through real time polymerase chain reaction (PCR) for the presence of SNPs in the NR1I2. Questionnaires on socio-demographic features and behaviors were answered and time of progression to AIDS was estimated based on medical chart analysis. FINDINGS Patients with the GG genotype for rs7643645 were shown to be related with a more rapid disease progression when compared to GA and AA genotypes. This result was maintained by the Multivariate Cox Regression considering sex, ethnicity, and presence of HLA-B*57, HLA-B*27, and CCR5del32 polymorphisms. MAIN CONCLUSIONS Recent studies reported the expression of the nuclear receptors in T-Lymphocytes, suggesting their possible role in the immune response. In addition, nuclear receptors have been shown to inhibit the HIV replication, although no such mechanism has been thoroughly elucidated to date. This is the first time an association between NR1I2 polymorphism and time of progression to AIDS is reported and supports an apparent relationship between the gene in the immune response and identifies another genetic factor influencing AIDS progression.