Cutaneous disseminated sporotrichosis associated with diabetes: A case report and literature review

Drug to genome to drug: a computational large-scale chemogenomics screening for novel drug candidates against sporotrichosis

Sporotrichosis is recognized as the predominant subcutaneous mycosis in South America, attributed to pathogenic species within the Sporothrix genus. Notably, in Brazil, Sporothrix brasiliensis emerges as the principal species, exhibiting significant sapronotic, zoonotic and enzootic epidemic potential. Consequently, the discovery of novel therapeutic agents for the treatment of sporotrichosis is imperative. The present study is dedicated to the repositioning of pharmaceuticals for sporotrichosis therapy. To achieve this goal, we designed a pipeline with the following steps: (a) compilation and preparation of Sporothrix genome data; (b) identification of orthologous proteins among the species; (c) identification of homologous proteins in publicly available drug-target databases; (d) selection of Sporothrix essential targets using validated genes from Saccharomyces cerevisiae; (e) molecular modeling studies; and (f) experimental validation of selected candidates. Based on this approach, we were able to prioritize eight drugs for in vitro experimental validation. Among the evaluated compounds, everolimus and bifonazole demonstrated minimum inhibitory concentration (MIC) values of 0.5 µg/mL and 4.0 µg/mL, respectively. Subsequently, molecular docking studies suggest that bifonazole and everolimus may target specific proteins within S. brasiliensis- namely, sterol 14-α-demethylase and serine/threonine-protein kinase TOR, respectively. These findings shed light on the potential binding affinities and binding modes of bifonazole and everolimus with their probable targets, providing a preliminary understanding of the antifungal mechanism of action of these compounds. In conclusion, our research advances the understanding of the therapeutic potential of bifonazole and everolimus, supporting their further investigation as antifungal agents for sporotrichosis in prospective hit-to-lead and preclinical investigations.

Clinical Analysis of Patients Diagnosed with Cutaneous Sporotrichosis in China

Purpose

This study aimed to improve the understanding of sporotrichosis by analyzing the epidemiological characteristics, clinical manifestations, mycological features, and pathological characteristics of the disease in eastern China.

Methods

Clinical data of 49 patients diagnosed with cutaneous sporotrichosis in dermatology clinics over a 20-year period were collected and analyzed retrospectively. The analysis included patient demographics, occupations, clinical types, lesion sites, misdiagnosis rates, laboratory investigations, treatment and outcomes.

Results

The study included 22 male and 27 female patients, with a mean age of 52.4 years. Farmers (42.86%) and manual workers (28.57%) had a higher risk of infection. The most common clinical types were lymphocutaneous (30.61%) and fixed (69.39%), predominantly affecting the face and upper limbs. Misdiagnosis as other infectious skin diseases occurred in 35 patients (71.43%). Fungal culture and histopathological examination were important diagnostic tools. Treatment with oral itraconazole for three months led to relief and regression of the skin lesions in most patients, although a few experienced recurrences.

Conclusion

Cutaneous sporotrichosis mainly affects individuals working in agriculture and manual labour, with lymphocutaneous and fixed types being the predominant clinical manifestations. The high misdiagnosis rate emphasizes the importance of early recognition, accurate diagnosis and standardized treatment for the prognosis and cure of sporotrichosis. Fungal culture and histopathological examination are essential for diagnosis, and oral itraconazole is an effective treatment option.

Novel Insights into Sporotrichosis and Diabetes

Sporotrichosis is a type of zoonotic subcutaneous mycosis caused by different species of dimorphic fungus of the genus Sporothrix, and it is the most common form of subcutaneous mycosis in Latin America. Sporotrichosis is generally restricted to cutaneous and lymphatic tissue (i.e., localized forms), and involvement in the viscera (i.e., disseminated or disseminated cutaneous form) is uncommon, especially in the central nervous system. However, immunosuppression in individuals with diabetes mellitus can lead to the disseminated form of the disease due to a failure to eliminate the pathogen and poor infection treatment outcomes. Possible correlations between patients with diabetes and their greater susceptibility to disseminated cases of sporotrichosis include a decreased cytokine response after stimulation, increased oxidative stress, decreased chemotaxis, phagocytic activity, adhesion and rolling of neutrophils and monocytes/macrophages, and increased macrophage/monocyte and polymorphonuclear cell apoptosis. Therefore, this review highlights novel insights into diabetes and sporotrichosis by investigating how chronic inflammation affects and aggravates the infection, the possible causes of the greater susceptibility of Sporothrix sp. to hematogenous dissemination in immunocompromised patients, and the main alterations that this dissemination can cause.