Subcutaneous fungal infections

Microneedle-based arrays - Breakthrough strategy for the treatment of bacterial and fungal skin infections

Currently, fungal and bacterial skin infections rank among the most challenging public health problems due to the increasing prevalence of microorganisms and the development of resistance to available drugs. A major issue in treating these infections with conventional topical medications is the poor penetration through the stratum corneum, the outermost layer of the skin. The concept of microneedles seems to be a future-proof approach for delivering drugs directly into deeper tissues. By bypassing the skin barrier, microneedle systems allow therapeutic substances to reach deeper layers more efficiently, significantly improving treatment outcomes. Nonetheless, the primary challenges regarding the effectiveness of microneedles involve selecting the appropriate size and shape, along with polymer composition and fabrication technology, to enable controlled and efficient drug release. This review offers a comprehensive overview of the latest knowledge on microneedle types and manufacturing techniques, highlighting their potential effectiveness in treating bacterial and fungal skin infections. It includes updated statistics on infection prevalence and provides a detailed examination of common bacterial and fungal diseases, focusing on their symptoms, causative species, and treatment methods. Additionally, the review addresses safety considerations, regulatory aspects, and future perspectives for microneedle-based therapeutic systems. It also underscores the importance of industrialization and clinical translation efforts, emphasizing the significant potential of microneedle technology for advancing medical applications.

Humans vs. Fungi: An Overview of Fungal Pathogens against Humans

Human fungal diseases are infections caused by any fungus that invades human tissues, causing superficial, subcutaneous, or systemic diseases. Fungal infections that enter various human tissues and organs pose a significant threat to millions of individuals with weakened immune systems globally. Over recent decades, the reported cases of invasive fungal infections have increased substantially and research progress in this field has also been rapidly boosted. This review provides a comprehensive list of human fungal pathogens extracted from over 850 recent case reports, and a summary of the relevant disease conditions and their origins. Details of 281 human fungal pathogens belonging to 12 classes and 104 genera in the divisions ascomycota, basidiomycota, entomophthoromycota, and mucoromycota are listed. Among these, Aspergillus stands out as the genus with the greatest potential of infecting humans, comprising 16 species known to infect humans. Additionally, three other genera, Curvularia, Exophiala, and Trichophyton, are recognized as significant genera, each comprising 10 or more known human pathogenic species. A phylogenetic analysis based on partial sequences of the 28S nrRNA gene (LSU) of human fungal pathogens was performed to show their phylogenetic relationships and clarify their taxonomies. In addition, this review summarizes the recent advancements in fungal disease diagnosis and therapeutics.

Nanoparticles assisted intra and transdermic delivery of antifungal ointment: an updated review

This review paper highlights the trans-dermic delivery of nanoparticles (NPs) based antifungal ointments with the help of nanotechnology. It also describes the novel trans-dermal approach utilizing various nanoparticles which enables an efficient delivery to the target site. This current review gives an overview about past research and developments as well as the current nanoparticle-based ointments. This review also presents data regarding types, causes of infection, and different pathogens within their infection site. It also gives information about antifungal ointments with their activity and side effects of antifungal medicines. Additionally, this review also focuses on the future aspects of the topical administration of nanoparticle-based antifungal ointments. These nanoparticles can encapsulate multiple antifungal drugs as a combination therapy targeting different aspects of fungal infection. Nanoparticles can be designed in such a way that they can specifically target fungal cells and do not affect healthy cells. Nanoparticle based antifungal ointments exhibit outstanding potential to treat fungal diseases. As further research and advancements evolve in nanotechnology, we expect more development of nanoparticle-based antifungal formulations shortly. This paper discusses all the past and future applications, recent trends, and developments in the various field and also shows its bright prospective in the upcoming years.

Implantation Mycoses and Invasive Fungal Infections with Cutaneous Involvement in Tropical Taiwan: An 11-Year Retrospective Study of a Medical Center

Background: The rising incidence of implantation mycoses and invasive fungal infections prompts the need for studies describing the latest trends of these diseases; however, the literature remains scarce from tropical Asia in recent years. We shared our 11-year clinical experience at a tertiary center in Southern Taiwan to improve physicians’ understanding of the diseases, which could help them assume appropriate management strategies. Patients and methods: Forty cases of pathology-proven cases of implantation mycoses and invasive fungal infections with cutaneous involvement were retrospectively reviewed. The epidemiology, patients’ characteristics, initial clinical impressions, fungal species, management, and outcomes were compared and reported. Results: Fonsecaea sp. was the most commonly (14%) involved species in implantation mycoses. The percentages of immunocompromised patients with implantation mycoses and invasive fungal infections were 26% and 60%, respectively. Additionally, 46% of patients with implantation mycoses had type 2 diabetes mellitus. The lesions were commonly mistaken for skin appendage tumors, skin cancers, and hyperkeratotic dermatoses. The prognosis was favorable for the implantation mycoses (83% showed clinical improvement) but bleak for the invasive fungal infections (100% mortality). Conclusions: Presentations of implantation mycoses and invasive fungal infections vary widely, and immunocompromised status and diabetes mellitus are important associated factors.

Multiple facial candidal abscesses after self-administered acupuncture in a patient with undiagnosed diabetes mellitus: a case report

Background

Facial abscess caused by Candida albicans infection is a rare condition even in immunocompromised patients, and only a few cases have been reported. To our knowledge, this is the first case of multiple facial candidal abscesses caused by self-administered acupuncture in an undiagnosed diabetes mellitus patient.

Case presentation

A 57-year-old woman who had self-acupuncture treatment 2 weeks previously, presented with a 1-week history of progressive left eyelid swelling, erythema, and pain. Despite the antibiotic treatment, the lesion progressed. Surgical incision and drainage was performed and Candida albicans was isolated from the obtained pus culture. The patient was diagnosed with type 2 diabetes mellitus based on a random serum glucose level of 350 mg/dl and 9.2% HbA1c. The abscess resolved after seven incision and drainage cycles and 4 weeks of intravenous fluconazole treatment with an appropriate control of diabetes mellitus.

Conclusion

Unusual organisms and underlying immunocompromised condition should be suspected in cases of recurrent abscess showing an inadequate response to antibiotic treatment.

Melanin and chromoblastomycosis agents: Characterization, functions, and relation with antifungals

Melanins are a diverse group of dark pigments with similar properties. In fungi, the most studied is the dihydroxynaphtalene (DHN)-melanin, present in several species including all the chromoblastomycosis agents, a chronic, disabling, and recalcitrant subcutaneous mycosis. It is synthesized in a pathway known as the pentaketide pathway, which has the agrochemical tricyclazole as an inhibitor, widely used in in vitro studies because it does not prevent the growth of fungi. There are different methodologies for qualitative and quantitative analyses of DHN-melanin, which made it possible to discover its important structural and antioxidant functions, with melanin acting as a protective factor against the host's immune system. Also, it can interact with some of the main antifungals of medical interest, reducing its activity and the susceptibility of fungi to these agents. This review aims to discuss the aspects of DHN-melanin, focusing on chromoblastomycosis, bringing the main findings of the published scientific studies, and highlighting the need for further research to understand this important fungal pathogenicity and a virulence factor.

Case series of sporotrichosis at a teaching hospital in Brazil

INTRODUCTION:

Sporotrichosis is a subcutaneous fungal infection with a worldwide distribution and higher incidence in tropical and subtropical areas, such as the Brazilian territory, where it has been standing out due to its frequent epidemics. Thus, the present study aimed to evaluate the prevalence of sporotrichosis and profile the affected patients at a university teaching hospital in the central region of Rio Grande do Sul, Brazil.

METHODS:

This study was a case series of patients diagnosed with Sporothrix spp. from January 2006 to December 2015 by microscopic examination or fungal isolates. Medical records were reviewed for epidemiological data.

RESULTS:

Forty-three cases of sporotrichosis were diagnosed through the period. The sample comprised predominantly young male adults and rural workers. The most common disease type was lymphocutaneous (51%), followed by fixed cutaneous form (32.5%). The predominant location was the upper limbs (70%), followed by the lower limbs (16%). A significant association was observed between the lymphocutaneous form and upper limb location and between the fixed cutaneous form and lower limb location (p = 0.019). Potassium iodine and itraconazole were the most common treatments.

CONCLUSIONS:

This study will help update the epidemiological situation of sporotrichosis in the central region of the state of Rio Grande do Sul, Brazil, over the last decade.

Chromoblastomycosis

Chromoblastomycosis (CBM), also known as chromomycosis, is one of the most prevalent implantation fungal infections, being the most common of the gamut of mycoses caused by melanized or brown-pigmented fungi. CBM is mainly a tropical or subtropical disease that may affect individuals with certain risk factors around the world. The following characteristics are associated with this disease: (i) traumatic inoculation by implantation from an environmental source, leading to an initial cutaneous lesion at the inoculation site; (ii) chronic and progressive cutaneous and subcutaneous tissular involvement associated with fibrotic and granulomatous reactions associated with microabscesses and often with tissue proliferation; (iii) a nonprotective T helper type 2 (Th2) immune response with ineffective humoral involvement; and (iv) the presence of muriform (sclerotic) cells embedded in the affected tissue. CBM lesions are clinically polymorphic and are commonly misdiagnosed as various other infectious and noninfectious diseases. In its more severe clinical forms, CBM may cause an incapacity for labor due to fibrotic sequelae and also due to a series of clinical complications, and if not recognized at an early stage, this disease can be refractory to antifungal therapy.

Subcutaneous mycoses in Peru: a systematic review and meta-analysis for the burden of disease

BACKGROUND

There is a worrying lack of epidemiological data on the geographical distribution and burden of subcutaneous mycoses in Peru, hindering the implementation of surveillance and control programs.

OBJECTIVES

This study aimed to estimate the disease burden of subcutaneous mycoses in Peru and identify which fungal species were commonly associated with these mycoses.

METHODS

We performed a meta-analysis after a systematic review of the published literature in PubMed, LILACS, and SciELO to estimate the burden of subcutaneous mycoses in 25 regions in Peru. The disease burden was determined in terms of prevalence (number of cases per 100,000 inhabitants) and the number of reported cases per year per region.

RESULTS

A total of 26 studies were eligible for inclusion. Results showed that sporotrichosis was the most common subcutaneous mycosis (99.7%), whereas lobomycosis, chromoblastomycosis, and subcutaneous phaeohyphomycosis were rare. Cases of eumycetoma and subcutaneous zygomycosis were not found. Of the 25 regions, the burden of sporotrichosis was estimated for four regions classified as endemic; in nine regions, only isolated cases were reported. The highest burden of sporotrichosis was in Apurimac (15 cases/100,000 inhabitants; 57 cases/year), followed by Cajamarca (3/100,000 inhabitants; 30/year), Cusco (0.5/100,000 inhabitants; 4/year), and La Libertad (0.2/100,000 inhabitants; 2/year). In two regions, the mycoses predominantly affected children.

CONCLUSIONS

Sporotrichosis is the most common subcutaneous mycosis in Peru, with a high disease burden in Apurimac. Chromoblastomycosis, lobomycosis, and subcutaneous phaeohyphomycosis are rare mycoses in Peru.

Involvement of major components from Sporothrix schenckii cell wall in the caspase-1 activation, nitric oxide and cytokines production during experimental sporotrichosis

Sporotrichosis is a chronic infection caused by the dimorphic fungus Sporothrix schenckii, involving all layers of skin and the subcutaneous tissue. The role of innate immune toll-like receptors 2 and 4 in the defense against this fungus has been reported, but so far, there were no studies on the effect of cell wall major components over the cytosolic oligo-merization domain (NOD)-like receptors, important regulators of inflammation and responsible for the maturation of IL-1β and IL-18, whose functions are dependents of the caspase-1 activation, that can participate of inflammasome. It was evaluated the percentage of activation of caspase-1, the production of IL-1β, IL-18, IL-17, IFN-γ and nitric oxide in a Balb/c model of S. schenckii infection. It was observed a decreased activity of caspase-1 during the fourth and sixth weeks of infection accompanied by reduced secretion of the cytokines IL-1β, IL-18 and IL-17 and high production of nitric oxide. IFN-γ levels were elevated during the entire time course of infection. This temporal reduction in caspase-1 activity coincides exactly with the reported period of fungal burden associated with a transitory immunosuppression induced by this fungus and detected in similar infection models. These results indicate the importance of interaction between caspase-1, cytokines IL-1β and IL-18 in the host defense against S. schenckii infection, suggesting a participation the inflammasome in this response.

Overview of vertebrate animal models of fungal infection

Fungi represent emerging infectious threats to human populations worldwide. Mice and other laboratory animals have proved invaluable in modeling clinical syndromes associated with superficial and life-threatening invasive mycoses. This review outlines salient features of common vertebrate animal model systems to study fungal pathogenesis, host antifungal immune responses, and antifungal compounds.

Management of mycetomas in France

OBJECTIVE OF THE STUDY

Mycetomas are chronic sub-cutaneous tropical infections in which exogenous causative agents, fungal (eumycetes) or bacterial (actinomycetes), generate grains. The typical presentation is multi-fistulized pseudotumors. This disease, particularly eumycetoma, is difficult to treat. It is a major health problem in tropical and subtropical countries. In France, the disease is rare, but patients have access to a broader range of treatments. The authors had for objective to present the cases of mycetomas diagnosed in developed country and their management.

PATIENTS AND METHODS

A retrospective study was made on the clinical presentation and management of mycetomas from 1995 to 2011, in the Bobigny Avicenne teaching hospital.

RESULTS

Six patient files were studied. The patients were men with a median age of 31 years (16-70). Five patients were from Sub Saharan Africa, one from Sri Lanka. The etiologies were one actinomycetoma and five eumycetomas. There was bone involvement in five cases. There was one atypical presentation: a primary intra-osseous mycetoma. Three patients were cured including two by surgical management and one by medical treatment (actinomycetoma). Antifungal therapy failed (four patients) in every case (voriconazole, itraconazole, ketoconazole, terbinafine, caspofungin).

CONCLUSION

The results of this study made in a non-epidemic zone revealed that despite a typical clinical presentation, the diagnosis and management were delayed because this imported disease is rare in France. The patients received new broad-spectrum triazole and caspofungin, but none were cured with antifungal therapy alone.