Humane Endpoint: Example from a Murine Model of Disseminated Sporotrichosis.

Vertebrate animal models are essential in research; however, efforts need to be made to decrease animal suffering as much as possible. It could be useful to determine humane endpoints that could serve as surrogates for a fatal outcome. We address this issue with respect to infectious diseases. We propose a humane endpoint for studies of Sporothrix brasiliensis infection. BALB/c mice were inoculated subcutaneously in the footpad. To define a humane endpoint, we considered two groups: animals who died during the experiment, and those euthanized at the end of the experiment. The groups were compared for colony-forming units (CFU) in internal organs, clinical condition, and body weight. Thirteen (22%) animals died before the end of the experiment due to the progression of local infection to severe and disseminated sporotrichosis. Analyzing data of the groups, we propose the following future criteria for euthanasia as a humane endpoint: neurological impairment OR necrosis of the footpad OR loss of ≥ 20% body weight AND moderate to severe dehydration. In view of the current global epidemiological impact of zoonotic sporotrichosis caused by S. brasiliensis, our data could facilitate the utility of models used to study the disease, particularly therapy.

Amlodipine and lufenuron as repurposing drugs against Sporothrix brasiliensis.

Background: Sporotrichosis caused by Sporothrix brasiliensis is a globally emerging infectious disease with limited therapeutic options. Thus, we aimed to evaluate the in vitro activity of amlodipine (AML) and lufenuron (LUF) alone and their interaction with itraconazole (ITZ), the first-choice drug against S. brasiliensis. Methods: Twenty clinical isolates of S. brasiliensis from two hyperendemic regions were tested through a microdilution assay to evaluate the minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) of AML and LUF. Checkerboard assay was performed with 10 isolates for both drug interactions with ITZ. Results: AML showed inhibitory and fungicidal activity against all isolates included, with MIC values ranging from 32 to 256 µg/mL, and MFC from 64 to 256 µg/mL. However, none of the S. brasiliensis isolates were inhibited by the highest soluble concentration of LUF (MIC >64 µg/mL for all strains). Synergic interaction of AML and LUF with ITZ occurred in 50% and 40% of the isolates tested, without any antagonistic effects. Conclusion: Both repurposing drugs evaluated in our study showed a promising in vitro activity, especially in synergy with ITZ against S. brasiliensis, warranting future in vivo investigations regarding its activity.

Sporothrix brasiliensis: Epidemiology, Therapy, and Recent Developments.

Sporotrichosis caused by Sporothrix brasiliensis is an emergent mycosis that is now a worldwide concern. One important step to sporotrichosis control is its correct treatment. However, limitations abound; thus, new antifungals, mainly focused on S. brasiliensis, are urgently needed. We performed a systematic review (following the PRISMA guideline) focused on (1) the global distribution of human and animal sporotrichosis by S. brasiliensis, especially outside of Brazil; (2) appraising therapies tested against this pathogen. We identified sporotrichosis caused by S. brasiliensis reported in five countries (Paraguay, Chile, Argentina, the United Kingdom, and the United States) in addition to Brazil, occurring on three continents, highlighting the epidemiological scenario in Argentina with an important increase in reported cases in recent years. Regarding the antifungal activity of drugs, 25 articles described the in vitro action of 20 unique chemicals and eight repurposed drugs against S. brasiliensis. Only five studies reported in vivo activity against S. brasiliensis (five drugs) using invertebrate and vertebrate models. Sporotrichosis caused by S. brasiliensis has a global impact and it is no longer specifically a Brazilian problem. We review the need for understanding the disease epidemiology, education of clinicians and of the populace, organization of health care delivery to respond to a spreading epidemic, and research on therapy for sporotrichosis.

Systemic aspergillosis associated with acute enterocolitis in foals.

Aspergillosis is an uncommon disease in horses, but it can be fatal. We report two cases of systemic aspergillosis in foals that occurred in a short period in the same region of southern Brazil. In addition, a literature review of similar cases was also performed. Risk factors were attributed to an immunodepression by primary enterocolitis and corticosteroid treatment, the damage in the epithelium, and multiple antibacterial treatments, which allowed local fungal proliferation, tissue invasion and spread of infection, leading to death. Since the antemortem diagnosis of aspergillosis in foals is difficult, our report alerts equine veterinarians regarding the importance of suspecting and investigating fungal co-infections in complicated cases of enterocolitis.

Nikkomycin Z for the treatment of experimental sporotrichosis caused by Sporothrix brasiliensis.

Sporotrichosis caused by Sporothrix brasiliensis is a global emergent infectious disease. Due to the scarcity of therapeutic options for fungal diseases, new antifungals are urgently needed. Nikkomycin Z (NikZ) is a future option as an agent against dimorphic fungi. We evaluated NikZ monotherapy and in combination with itraconazole (ITZ; the conventional therapy) in the treatment of experimental sporotrichosis caused by S. brasiliensis in a murine model. Animals were subcutaneously infected, and treated orally for 30 days. The study groups were as follows control (untreated), ITZ group (50 mg/kg/day), and three groups treated with NikZ, two by monotherapy (200 or 400 mg/kg/day), and one combining NikZ (400 mg/kg/day) and ITZ. Efficacy of treatments was evaluated via body weight gain, mortality and fungal burden in tissues. Efficacy was noted in all treatment groups, and the group receiving the drug combination showed even better results than those with monotherapy. Our study shows for the first time the high potential of NikZ to be used in the treatment of sporotrichosis caused by S. brasiliensis.

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.

Aspergillosis in free-ranging Magellanic penguins.

We evaluated the mortality due to aspergillosis in free-ranging Magellanic penguins during their migration and the reproductive season. A total of 98 carcasses of penguins were collected along 370 km of coastline in Southern Brazil, between June 2017 and October 2019, and from reproductive colonies in Patagonian Argentina, in January 2019. All animals were necropsied, and only proven cases were computed. Aspergillosis was diagnosed in 2.5% of the penguins evaluated during their migration route. Our study, of the Southern coast of Brazil, is the first to demonstrate that aspergillosis is an important cause of mortality in free-ranging penguins. The implications of these findings in the One Health context are discussed.

We evaluated the mortality due to aspergillosis in free-ranging Magellanic penguins during their migration and the reproductive season. The mortality rate of penguins was 2.5% during their migration route. Our study is the first to demonstrate aspergillosis as an important cause of mortality in free-ranging penguins.

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.

Tattooing as a gateway to Sporothrix brasiliensis infection.

Recently, sporotrichosis caused by Sporothrix brasiliensis transmitted during tattooing process was described in the epicenter of the Brazilian epidemic sporotrichosis. We report a similar case of this mycosis in a patient recently tattooed, but probably infected by a sick cat instead of via a contaminated procedure. Clinical cure was attained after two months of oral itraconazole. In the hyperendemic S. brasiliensis regions of sporotrichosis, health professionals must be aware of atypical transmissions of this fungus.

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.

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.