Practice guidelines for the management of patients with sporotrichosis. For the Mycoses Study Group. Infectious Diseases Society of America

Development and evaluation of a rapid diagnostic method for Sporothrix globosa in Asia using quantitative real-time PCR

BACKGROUND

Sporotrichosis is a chronic granulomatous infection of the skin and subcutaneous tissue that can affect any organ through lymphatic spread. The prevalence of sporotrichosis infections is increasing and its treatment is challenging as there are no unified and standard diagnostic techniques or antifungal medications. Controlling further spread requires a rapid diagnosis. Assessment of clinical symptoms, histological analysis, serological testing, and pathogen culture are all necessary for the diagnosis of sporotrichosis. However, these procedures are unable to identify the species. The development of safe, reliable, and species-specific diagnostic techniques is essential.

OBJECTIVE

To establish and evaluate a new quantitative real-time PCR assay for the rapid diagnosis of sporotrichosis and to identify relevant species.

METHODS

Polymorphisms in calmodulin (CAL) gene sequences and the internal transcribed spacer (ITS) were used in a quantitative real-time PCR assay to identify S. globosa, S. schenckii, and non-target species.

RESULTS

The quantitative real-time PCR assay had 100% sensitivity and specificity. The limit of detection was 6 fg/µl. Thirty-four clinical specimens were verified to be infected with S. globosa with a 100% positive detection rate.

CONCLUSIONS

The quantitative PCR technique developed in this study is a quick, accurate, and targeted method of identifying S. globosa based on polymorphisms in CAL sequences and ITS. It can be used for a prompt clinical diagnosis to identify S. globosa in clinical specimens from patients with sporotrichosis.

Dermoscopy of Fixed Cutaneous Sporotrichosis With a Follow-Up Till Cure: A Case Report

Fixed cutaneous sporotrichosis (FCS) is a rare and chronic infection. Its diagnosis requires a high degree of suspicion. The data on its dermoscopy and follow-up is limited in the literature. We herein report one such case with a follow-up till cure along with its dermoscopy to establish certain specific features that may be used to ascertain the response to treatment for this chronic infection and its prognosis. We found only three such cases following an extensive review of the literature, and this case emphasizes the importance of dermoscopy in recent times as the history, swab cultures, and smears may be misleading at times due to the chronic and long-standing nature of the condition.

Clinical characteristics, diagnosis, and treatment of central nervous system sporotrichosis: Systematic review and meta-analysis

BACKGROUND

The clinical features of central nervous system (CNS) sporotrichosis are derived from case reports and a limited series of cases. Our objective was to carry out a systematic review and meta-analysis of CNS sporotrichosis.

METHODS

We searched PubMed/MEDLINE, Embase, Scopus, and LILACS on 9 September 2023. Our inclusion criteria were documentation of Sporothrix and demonstrated CNS involvement. A metaproportion or metamean analysis was performed to estimate a summary proportion with 95% confidence intervals.

RESULTS

We included 52 cases of CNS sporotrichosis published from 1966 to 2023. Forty-six patients were male (88%, 95% CI: 77-95), and the mean age was 39 years (95% CI: 36-43). Close contact with cats was reported in 55% of cases (95% CI: 37-72). Thirty-two (61.5%) patients were from Brazil, 18 patients from the United State of America (34.6%). Only two Sporothrix species were reported: S. schenckii (26/41, 63%), and S. brasiliensis (15/41, 37%). The most common neurological symptom was headache. Meningitis was chronic in approximately 80% of cases. A significant majority of the patients were immunocompromised. HIV infection was the primary cause of immunosuppression (85%, 95% CI: 61-95). Overall mortality was 56% (22/39). The comparison of Kaplan-Meier survival curve showed a higher mortality with a statistically significant difference in immunosuppressed patients (p = .019).

CONCLUSION

CNS sporotrichosis represents a notable cause of chronic meningitis, especially in individuals living in the Americas with HIV infection and concurrent skin lesions.

Prevalence and Antifungal Susceptibility of Sporothrix species in Guangzhou, Southern China

INTRODUCTION

Sporotrichosis is a subcutaneous and chronic infection caused by traumatic inoculation of pathogenic sporothrix species, usually infecting the skins and subcutaneous tissues of humans and animals. However, the lack of epidemiological data required further molecular identification to describe the distribution of this fungus in our region. In this study, forty-eight clinical sporothrix isolated from Sun Yat-Sen Memorial Hospital were classified, and the susceptibility of each strain to seven antifungal agents was determined.

METHODS

Forty strains of S. globosa and eight strains of S. shenkshii were identified via colony morphology and PCR sequencing of calmodulin gene.

RESULTS

Antifungal susceptibility tests of the mycelial phase in vitro showed terbinafine (TRB) and luliconazole (LULI) were the most effective, followed by itraconazole (ITZ) and amphotericin B (AMB). By contrast, voriconazole (VCZ), 5-flucytosine (5FC) and fluconazole (FCZ) have low efficacy with high MIC.

CONCLUSION

Our results showed a predominantly S. globosa infection trend in southern China. Simultaneously, sporothrix is sensitive to TRB, LULI, ITZ and AMB whereas resistant to FCZ. This study firstly reports antifungal sensitivity test in vitro and epidemiological correlation analysis of sporothrix in southern China, and also the first time to find that sporothrix is sensitive to LULI.

Current Progress on Epidemiology, Diagnosis, and Treatment of Sporotrichosis and Their Future Trends

Sporotrichosis, a human and animal disease caused by Sporothrix species, is the most important implantation mycosis worldwide. Sporothrix taxonomy has improved in recent years, allowing important advances in diagnosis, epidemiology, and treatment. Molecular epidemiology reveals that S. brasiliensis remains highly prevalent during the cat-transmitted sporotrichosis outbreaks in South America and that the spread of S. brasiliensis occurs through founder effects. Sporothrix globosa and S. schenckii are cosmopolitan on the move, causing major sapronoses in Asia and the Americas, respectively. In this emerging scenario, one-health approaches are required to develop a creative, effective, and sustainable response to tackle the spread of sporotrichosis. In the 21st century, it has become vital to speciate Sporothrix, and PCR is the main pillar of molecular diagnosis, aiming at the detection of the pathogen DNA from clinical samples through multiplex assays, whose sensitivity reaches remarkably three copies of the target. The treatment of sporotrichosis can be challenging, especially after the emergence of resistance to azoles and polyenes. Alternative drugs arising from discoveries or repositioning have entered the radar of basic research over the last decade and point to several molecules with antifungal potential, especially the hydrazone derivatives with great in vitro and in vivo activities. There are many promising developments for the near future, and in this review, we discuss how these trends can be applied to the Sporothrix-sporotrichosis system to mitigate the advance of an emerging and re-emerging disease.

Disseminated sporotrichosis in a person with human immunodeficiency virus disease

Introduction

Disseminated sporotrichosis is an incapacitating infection caused by the dimorphic fungus Sporothrix schenckii. Because this condition may mimic the presentation of tuberculosis, syphilis and other bacterial infections, the diagnosis may be missed or delayed.

Case Presentation

We describe a case of disseminated sporotrichosis in a patient with poorly controlled human immunodeficiency virus infection. The patient was initially treated for bacterial skin infections. The differential diagnosis also included tuberculosis and syphilis. Only after appropriate specimens had been sent for microbiological and histopathological investigations was the diagnosis of disseminated sporotrichosis made and appropriate treatment started. The patient showed a good clinical response to itraconazole.

Conclusion

This report highlights the importance of having a high index of suspicion of endemic mycoses when managing immunocompromised patients. The report also demonstrates that a delay in the diagnosis of sporotrichosis increases morbidity and results in unnecessary and inappropriate treatment with associated costs and adverse effects.

Reactivation of latent infections in solid organ transplant recipients from sub-Saharan Africa: What should be remembered?

International migration from Sub-Saharan African countries to the European Union and the United States has significantly increased over the past decades. Although the vast majority of these immigrants are young and healthy people, a minority can be affected by chronic conditions eventually leading to solid organ transplantation (SOT). Importantly, these candidates can bear geographically restricted fungal and parasitic latent infections that can reactivate after the procedure. An appropriate evaluation before transplantation followed by treatment, whenever necessary, is essential to minimize such risk, as covered in the present review. In short, infection due to helminths (Schistosoma spp. and Strongyloides stercoralis) and intestinal protozoa (Entamoeba histolytica, Giardia lamblia or Cyclospora cayetanensis) can be diagnosed by multiple direct stool examination, serological assays and stool antigen testing. Leishmaniasis can be assessed by means of serology, followed by nucleic acid amplification testing (NAAT) if the former test is positive. Submicroscopic malaria should be ruled out by NAAT. Screening for Histoplasma spp. or Cryptococcus spp. is not routinely indicated. Consultation with an Infectious Diseases specialist is recommended in order to adjust preemptive treatment among Sub-Saharan African SOT candidates and recipients.

A One Health Approach to Combatting Sporothrix brasiliensis: Narrative Review of an Emerging Zoonotic Fungal Pathogen in South America

Cat-transmitted sporotrichosis caused by Sporothrix brasiliensis has become a major public health concern and presents a distinct divergence from the traditional epidemiology of sporotrichosis. This emerging fungal pathogen spreads readily among cat populations, and human infections occur exclusively via zoonotic transmission. While sporotrichosis is an implantation mycosis that typically manifests as cutaneous lesions in humans and cats, severe extracutaneous manifestations are more common with S. brasiliensis than other Sporothrix species infections. Rapid diagnosis and appropriate treatment regimens are critical for successful clinical resolution of sporotrichosis in both cats and humans. Species-level identification of Sporothrix is possible with molecular diagnostics and necessary for tracking the geographic expansion of S. brasiliensis and better understanding its epidemiology. Combatting cat-transmitted sporotrichosis requires a One Health approach to successfully implement public health control measures.

First case report of cutaneous sporotrichosis (Sporothrix species) in a cat in the UK

Case summary

A 12-year-old female neutered indoor-outdoor domestic longhair cat presented with frequent sneezing and a nodular, suppurative lesion on its dorsal nose. Histopathological examination revealed a fungal granuloma. PCR and sequencing of the ribosomal internal transcribed spacers (ITS) regions (ITS-F and ITS-R) confirmed an infection with a Sporothrix species. Further sequencing of the beta-tubulin and calmodulin genes confirmed Sporothrix humicola, which lies within the Sporothrix pallida complex. The cat had concurrent diabetes mellitus, which responded to insulin therapy and diet. Oral itraconazole at 10 mg/kg PO q24h resulted in resolution of the lesions after 12 months. Treatment was well tolerated.

Relevance and novel information

This is the first report of sporotrichosis in a cat in the UK and only the fifth worldwide involving the S pallida complex. Clinicians, pathologists and microbiologists need to be aware of the potential of Sporothrix infections in the UK and the ability of S pallida complex to cause opportunistic infections. Molecular techniques can achieve rapid and accurate identification of rare fungal organisms. A precise diagnosis with molecular testing can provide information regarding prognosis, treatment and zoonotic implications.

Delayed Diagnosis in a Case of Smoldering Sporotrichal Monoarthropathy

We present the clinical, imaging, and laboratory findings of a 41-year-old male with culture proven Sporothrix schenckii osteoarticular infection of the right knee. Fungal arthropathies are a rare and indolent form of septic arthritis, which often leads to a delayed diagnosis. Early diagnosis and treatment of fungal arthropathies is critical to preventing permanent functional disability.

Central Nervous System Infection with Other Endemic Mycoses: Rare Manifestation of Blastomycosis, Paracoccidioidomycosis, Talaromycosis, and Sporotrichosis

The central nervous system (CNS) is not a major organ involved with infections caused by the endemic mycoses, with the possible exception of meningitis caused by Coccidioides species. When CNS infection does occur, the manifestations vary among the different endemic mycoses; mass-like lesions or diffuse meningeal involvement can occur, and isolated chronic meningitis, as well as widely disseminated acute infection that includes the CNS, are described. This review includes CNS infection caused by Blastomyces dermatitidis, Paracoccidioides brasiliensis, Talaromyces marneffei, and the Sporothrix species complex. The latter is not geographically restricted, in contrast to the classic endemic mycoses, but it is similar in that it is a dimorphic fungus. CNS infection with B. dermatitidis can present as isolated chronic meningitis or a space-occupying lesion usually in immunocompetent hosts, or as one manifestation of widespread disseminated infection in patients who are immunosuppressed. P. brasiliensis more frequently causes mass-like intracerebral lesions than meningitis, and most often CNS disease is part of disseminated infection found primarily in older patients with the chronic form of paracoccidioidomycosis. T. marneffei is the least likely of the endemic mycoses to cause CNS infection. Almost all reported cases have been in patients with advanced HIV infection and almost all have had widespread disseminated infection. Sporotrichosis is known to cause isolated chronic meningitis, primarily in immunocompetent individuals who do not have Sporothrix involvement of other organs. In contrast, CNS infection in patients with advanced HIV infection occurs as part of widespread disseminated infection.

Disseminated Sporotrichosis in a Liver Transplant Patient: A Case Report

Sporotrichosis is an infection caused by the fungus of the Sporothrix schenckii complex and can be particularly harmful in immunocompromised patients. We report the case of a 26-year-old male patient with a previous history of pulmonary infection who underwent a liver transplant for Budd-Chiari syndrome. After the procedure, he presented with persistent fever and leukocytosis. On the 13th post-operative day, he was diagnosed with thrombosis of the hepatic artery and underwent a second liver transplant 15 days after the first procedure. After the retransplant, he presented daily episodes of fever, even after the use of several antimicrobial, antiviral, and antifungal agents. A number of negative cultures from different sites were obtained. After an acute episode of mental confusion, the growth of S schenckii was observed in cultures from cerebrospinal fluid and ascites obtained from a diagnostic paracentesis. Treatment with amphotericin B was started but the patient died on the fourth day of antifungal treatment, from a massive gastrointestinal hemorrhage. We found no previous report in the literature of spontaneous dissemination of S schenckii to the abdominal cavity causing peritonitis.

Efficient Treatment of Sporothrix globosa Infection Using the Antibody Elicited by Recombinant Phage Nanofibers

Antifungal therapy is used to treat sporotrichosis. However, there are several limitations in this therapy, such as development of drug resistance and potential health risks including liver injury. The purpose of our study was to evaluate the antifungal efficacy of antibody against the hybrid phage nanofibers displaying KPVQHALLTPLGLDR (phage-KR) in a fungal-infected mouse model. In this study, we extracte an antibody against hybrid phage nanofibers (phage-KR) from immunized mice and passively inoculate Sporothrix globosa (S. globosa) infected mice. The study shows that the antibody exhibits efficient inhibition efficacy of the S. globosa infection, including reduction of the progressive fungi colonizing, increase of animal survival rate and relief of organ inflammation in the mice. The results indicate that antibody against phage-KR may act as a potential strategy for safe and efficient treatment of S. globosa infections.

Primary Cutaneous Peripheral T-Cell Lymphoma in a Sporotrichoid Pattern: A Case Report

We present the extraordinary case of a 72-year-old man with a history of primary cutaneous peripheral T-cell lymphoma not otherwise specified (pcPTCL-NOS) previously controlled with topical agents who developed tumours in a sporotrichoid pattern. Culture of the tumours was negative, and histopathology showed findings consistent with recurrent pcPTCL. The tumours were successfully treated with localised radiation therapy. Sporotrichoid lesions are an extremely rare and atypical presentation of cutaneous lymphoma, with only 2 other cases reported in the literature. Our case reinforces the need to include cutaneous lymphoma in the differential diagnosis of nodules on the extremities spreading in a sporotrichoid pattern. Clinical recognition of this atypical presentation of cutaneous lymphoma allows for prompt, effective treatment, which might include localised radiation therapy.

Studies in Phylogeny, Development of Rapid IdentificationMethods, Antifungal Susceptibility, and Growth Rates of Clinical Strains of Sporothrix schenckii Complex in Japan

Sporotrichosis is a fungal infection caused by the Sporothrix species, which have distinct virulence profiles and geographic distributions. We performed a phylogenetic study in strains morphologically identified as Sporothrix schenckii from clinical specimens in Japan, which were preserved at the Medical Mycology Research Center, Chiba University. In addition, we examined the in vitro antifungal susceptibility and growth rate to evaluate their physiological features. Three hundred strains were examined using sequence analysis of the partial calmodulin gene, or polymerase chain reaction（PCR）method using newly designed species-specific primers; 291 strains were Sporothrix globosa and 9 strains were S. schenckii sensu stricto (in narrow sense, s. s.). S. globosa strains were further clustered into two subclades, and S. schenckii s. s. strains were divided into three subclades. In 38 strains of S. globosa for which antifungal profiles were determined, 4 strains (11%) showed high minimal inhibitory concentration (MIC) value for itraconazole. All tested strains of S. schenckii s. s. and S. globosa showed low sensitivity for amphotericin B. These antifungals are used for treatment of sporotrichosis when infection is severe. S. schenckii s. s. grew better than S. globosa; wherein S. globosa showed restricted growth at 35℃ and did not grow at 37℃. Our molecular data showed that S. globosa is the main causal agent of sporotrichosis in Japan. It is important to determine the antifungal profiles of each case, in addition to accurate species-level identification, to strategize the therapy for sporotrichosis.

The antifungal pipeline: a reality check

Invasive fungal infections continue to appear in record numbers as the immunocompromised population of the world increases, owing partially to the increased number of individuals who are infected with HIV and partially to the successful treatment of serious underlying diseases. The effectiveness of current antifungal therapies - polyenes, flucytosine, azoles and echinocandins (as monotherapies or in combinations for prophylaxis, or as empiric, pre-emptive or specific therapies) - in the management of these infections has plateaued. Although these drugs are clinically useful, they have several limitations, such as off-target toxicity, and drug-resistant fungi are now emerging. New antifungals are therefore needed. In this Review, I discuss the robust and dynamic antifungal pipeline, including results from preclinical academic efforts through to pharmaceutical industry products, and describe the targets, strategies, compounds and potential outcomes.

A 27-Year-Old Severely Immunosuppressed Female with Misleading Clinical Features of Disseminated Cutaneous Sporotrichosis

Sporotrichosis is a subacute or chronic granulomatous mycosis caused by fungus of the Sporothrix schenckii complex. It is considered to be a rare condition in most parts of the world. It mostly causes cutaneous infection but can also cause multisystemic disease. Unlike most deep cutaneous mycoses which have a primary pulmonary focus, it is usually caused by direct inoculation of the fungus into the skin causing a classical linear, lymphocutaneous nodular eruption. However, atypical presentations of the condition can occur especially in immunosuppressed individuals. We report the case of a severely immunosuppressed female who presented with disseminated cutaneous sporotrichosis which was initially diagnosed and treated as disseminated cutaneous Kaposi's sarcoma.

Sporotrichosis: an overview and therapeutic options

Sporotrichosis is a chronic granulomatous mycotic infection caused by Sporothrix schenckii, a common saprophyte of soil, decaying wood, hay, and sphagnum moss, that is endemic in tropical/subtropical areas. The recent phylogenetic studies have delineated the geographic distribution of multiple distinct Sporothrix species causing sporotrichosis. It characteristically involves the skin and subcutaneous tissue following traumatic inoculation of the pathogen. After a variable incubation period, progressively enlarging papulo-nodule at the inoculation site develops that may ulcerate (fixed cutaneous sporotrichosis) or multiple nodules appear proximally along lymphatics (lymphocutaneous sporotrichosis). Osteoarticular sporotrichosis or primary pulmonary sporotrichosis are rare and occur from direct inoculation or inhalation of conidia, respectively. Disseminated cutaneous sporotrichosis or involvement of multiple visceral organs, particularly the central nervous system, occurs most commonly in persons with immunosuppression. Saturated solution of potassium iodide remains a first line treatment choice for uncomplicated cutaneous sporotrichosis in resource poor countries but itraconazole is currently used/recommended for the treatment of all forms of sporotrichosis. Terbinafine has been observed to be effective in the treatment of cutaneous sporotrichosis. Amphotericin B is used initially for the treatment of severe, systemic disease, during pregnancy and in immunosuppressed patients until recovery, then followed by itraconazole for the rest of the therapy.

Genetic diversity and antifungal susceptibility profiles in causative agents of sporotrichosis

Background

Sporotrichosis is a chronic subcutaneous mycosis of humans and animals, which is typically acquired by traumatic inoculation of plant material contaminated with Sporothrix propagules, or via animals, mainly felines. Sporothrix infections notably occur in outbreaks, with large epidemics currently taking place in southeastern Brazil and northeastern China. Pathogenic species include Sporothrix brasiliensis, Sporothrix schenckii s. str., Sporothrix globosa, and Sporothrix luriei, which exhibit differing geographical distribution, virulence, and resistance to antifungals. The phylogenetically remote species Sporothrix mexicana also shows a mild pathogenic potential.

Methods

We assessed a genetically diverse panel of 68 strains. Susceptibility profiles of medically important Sporothrix species were evaluated by measuring the MICs and MFCs for amphotericin B (AMB), fluconazole (FLC), itraconazole (ITC), voriconazole (VRC), posaconazole (PCZ), flucytosine (5FC), and caspofungin (CAS). Haplotype networks were constructed to reveal interspecific divergences within clinical Sporothrix species to evaluate genetically deviant isolates.

Results

ITC and PCZ were moderately effective against S. brasiliensis (MIC₉₀ = 2 and 2 μg/mL, respectively) and S. schenckii (MIC₉₀ = 4 and 2 μg/mL, respectively). PCZ also showed low MICs against the rare species S. mexicana. 5FC, CAS, and FLC showed no antifungal activity against any Sporothrix species. The minimum fungicidal concentration ranged from 2 to >16 μg/mL for AMB against S. brasiliensis and S. schenckii, while the MFC₉₀ was >16 μg/mL for ITC, VRC, and PCZ.

Conclusion

Sporothrix species in general showed high degrees of resistance against antifungals. Evaluating a genetically diverse panel of strains revealed evidence of multidrug resistant phenotypes, underlining the need for molecular identification of etiologic agents to predict therapeutic outcome.

Itraconazole (Sporanox®) in superficial and systemic fungal infections

Itraconazole (Sporanox) is a triazole antifungal agent with a broad activity spectrum and favorable pharmacokinetic and safety profiles. Numerous clinical trials have established the efficacy and safety of itraconazole in the treatment of superficial fungal infections. In this field, full exploitation of its pharmacokinetics in keratinized tissues has led to the development of intermittent (pulse) treatment regimens that allow similar efficacy with lower overall drug exposure as well as a reduction in treatment costs. The additional anti-inflammatory action of itraconazole also makes it suitable for application in difficult-to-treat inflammatory skin disorders, such as seborrheic dermatitis. Recently, a new oral liquid formulation and an intravenous formulation have been developed, extending the therapeutic application of itraconazole to systemic fungal infections. Due to its broad activity spectrum and excellent tolerability, itraconazole is a valuable addition to the antifungal armamentarium used for prophylactic and empiric treatment in immunocompromised hosts.

Recent advances in antifungal pharmacotherapy for invasive fungal infections

Invasive fungal infections carry significant morbidity and mortality. Candida species have become one of the most frequent causes of bloodstream infections, and infections caused by molds such as Aspergillus are becoming more frequent in immunocompromised patients. As this population grows, more invasive fungal infections can be anticipated. In the past, treatment options have been limited for many of these infections due to toxicity and efficacy concerns with the available antifungals. Fortunately, the past few years have brought exciting developments in antifungal pharmacotherapy. Lipid-based formulations of amphotericin B were introduced in the 1990s to attenuate adverse effects caused by amphotericin B deoxycholate (Fungizone, Bristol-Myers Squibb). Most recently, the echinocandins have been added to our antifungal regimen with the introduction of caspofungin (Cancidas, Merck and Co.) and voriconazole (Vfend, Pfizer), a new triazole, has come to market. The introduction of the echinocandins has invigorated the discussion about combination antifungal therapy. Evidence-based studies using these new agents are accumulating, and they are assuming important roles in the pharmacotherapy of invasive fungal infections in seriously ill and complex patients.

Cutaneous sporotrichosis treated with photodynamic therapy: an in vitro and in vivo study

BACKGROUND

Sporotrichosis is a fungal infection caused by Sporothrix schenckii complex, usually restricted to the skin, subcutaneous cellular tissue, and adjacent lymphatic vessels. Antimicrobial photodynamic therapy (aPDT) could be a good alternative to manage localized, superficial infections.

CASE REPORT

A 65-year-old African woman was diagnosed with a fixed cutaneous sporotrichosis on her left arm, treated with itraconazol and oral terbinafine with partial improvement. Topical 16% methyl aminolevulinate (MAL, Metvix(®))-PDT was used without success.

METHODS

An in vitro photoinactivation test with the isolated microorganism revealed phenothiazinium salts to be more effective than MAL.

CONCLUSIONS

PDT with intralesional 1% methylene blue (MB) in combination with intermittent low doses of itraconazole obtained complete microbiological and clinical response.

Application of 6-nitrocoumarin as a substrate for the fluorescent detection of nitroreductase activity in Sporothrix schenckii

Introduction

Sporothrix schenckii is a thermal dimorphic pathogenic fungus causing a subcutaneous mycosis, sporotrichosis. Nitrocoumarin represents a fluorogenic substrate class where the microbial nitroreductase activity produces several derivatives, already used in several other enzyme assays. The objective of this study was the analysis of 6-nitrocoumarin (6-NC) as a substrate to study the nitroreductase activity in Sporothrix schenckii.

Methods

Thirty-five samples of S. schenckii were cultivated for seven, 14 and 21 days at 35 °C in a microculture containing 6-nitrocoumarin or 6-aminocoumarin (6-AC) dissolved in dimethyl sulfoxide or dimethyl sulfoxide as a negative control, for posterior examination under an epifluorescence microscope. The organic layer of the seven, 14 and 21-day cultures was analyzed by means of direct illumination with 365 nm UV light and by means of elution on G silica gel plate with hexane:ethyl acetate 1:4 unveiled with UV light.

Results

All of the strains showed the presence of 6-AC (yellow fluorescence) and 6-hydroxylaminocoumarin (blue fluorescence) in thin layer chromatography, which explains the green fluorescence observed in the fungus structure.

Conclusion

The nitroreductase activity is widely distributed in the S. schenckii complex and 6-NC is a fluorogenic substrate of easy access and applicability for the nitroreductase activity detection.

Systemic mycoses in immunodepressed patients (AIDS)

Infectious and noninfectious skin diseases are observed in about 90% of HIV patients, and their incidence increases and is more severe as the immune system weakens. Cutaneous manifestations are considered good clinical predictors for the immunological condition of the patient with AIDS and the introduction of highly effective antiretroviral therapy totally changed the prognosis of the mycoses, among other diseases associated with AIDS, permitting longer survival and acceptable level of quality of life for these patients. This contribution describes the systemic mycoses that are more frequent in the seropositive population, that is, patients with HIV/AIDS, which are cryptococcosis, histoplasmosis, coccidioidomycosis, blastomycosis, paracoccidioidomycosis, sporotrichosis, penicilliosis, and aspergillosis. Their causative agents, mode of transmission, clinics, laboratorial diagnosis and therapy, in the aspects related to immunodepressed patients, are reviewed.

Pulmonary sporotrichosis: case series and systematic analysis of literature on clinico-radiological patterns and management outcomes

Pulmonary infections by Sporothrix spp. manifest radiologically as cavitary or non-cavitary disease depending on whether the infection is primary pulmonary or multifocal sporotrichosis. Despite current guidelines, the optimal management for pulmonary sporotrichosis remains unclear. In order to clarify this, we present two cases of pulmonary sporotrichosis, as well as the results of a comprehensive literature review of treatment outcomes based on clinico-radiological presentation patterns of the disease. A literature search of all case reports in English language over the last 50 years (1960-2010) was conducted. Data on patient characteristics, risk factors, clinico-radiological patterns, treatment modalities and outcomes were collected and analyzed. A total of 86 cases were identified, i.e., 64 (74.4%) primary pulmonary and 22 (25.6%) multifocal sporotrichosis. Radiologically, primary pulmonary disease was commonly characterized by cavity formation which was lacking in multifocal infections (P = 0.0001). Immunosuppressant use was more common in multifocal sporotrichosis (P = 0.0001), while hemoptysis was more common in primary pulmonary form (P = 0.01). No other differences in patient characteristics or risk factors were noted. Extra-pulmonary multifocal sporotrichosis most commonly involved skin (81.8%) and joints (45.4%). For patients with cavitary primary pulmonary sporotrichosis, outcomes from medical therapy alone were inferior to surgical intervention (P = 0.02). However, for both primary pulmonary and multifocal sporotrichosis with non-cavitary disease, medical therapy alone provided good outcomes. Only 12 (16.7%) cases were treated with itraconazole. Treatment of pulmonary sporotrichosis should be guided by the clinico-radiological patterns of presentation. Medical therapy alone is likely sufficient for non-cavitary disease while early surgery should be considered for cavitary primary pulmonary sporotrichosis. The experience in treating cavitary disease with itraconazole alone is limited and further data are required.

Cutaneous sporotrichosis: a six-year review of 19 cases in a tertiary referral center in Malaysia

BACKGROUND

Sporotrichosis is a subcutaneous fungal infection caused by a thermally dimorphic aerobic fungus, Sporothrix schenckii. It results from traumatic inoculation or contact with animals. Most cases were reported mainly in the tropics and subtropics.

OBJECTIVE

  The objective of our study is to assess the clinical characteristic of cutaneous sporotrichosis among our patients.

METHODOLOGY

We performed a retrospective review of all cases diagnosed with cutaneous sporotrichosis from July 2004 to June 2010. Patients' medical records were retrieved and analyzed according to demography, preceding trauma, sites of lesions, clinical subtypes, treatment, and clinical response.

RESULTS

Nineteen cases were diagnosed with cutaneous sporotrichosis with a male/female ratio of 9:10. Thirteen cases (68.4%) were able to recall preceding trauma, and seven of them reported cat scratches or cat bites. Lymphocutaneous sporotrichosis was observed in 13 cases (68.4%) followed by four cases of fixed cutaneous sporotrichosis and two cases of disseminated sporotrichosis. Histologically, 11 cases (57.8%) demonstrated a granulomatous reaction. Sporothrix schenckii was cultured in 12 cases (63.2%). Thirteen cases (68.4%) were successfully treated with oral itraconazole alone for a mean duration of 15.6 weeks. Two cases with disseminated cutaneous sporotrichosis were treated with intravenous amphotericin B.

CONCLUSION

  Lymphocutaneous sporotrichosis was the most common subtype of cutaneous sporotrichosis in our series, with cat scratches or bites being the most common preceding trauma. Oral itraconazole was highly effective for the localized subtypes, whereas intravenous amphotericin B was required in disseminated cutaneous sporotrichosis.

Lymphocutaneous sporotrichosis in an adolescent girl presenting as mycetoma

A 13-year-old girl presented with multiple painless purulent ulcers with raised borders on the medial aspect of the sole of her right foot associated with inguinal lymphadenopathy for the past 4 years. There was history of local trauma at the site prior to the formation of ulcers. There were no other significant associated signs or symptoms. The patient was initially treated with multiple antibiotics with minimal improvement. Fungal cultures of biopsy specimens demonstrated the presence of colonies of Sporothrix schenckii thus confirming the diagnosis of sporotrichosis. Oral itraconazole at the dose of 100 mg twice daily was initiated with marked response at 4 weeks. This case demonstrated a rare morphological presentation of the lymphocutaneous sporotrichosis as mycetoma. The possible diagnosis of sporotrichosis should be kept in mind in such a clinical presentation not responding to antibiotics. Cutaneous sporotrichosis should be diagnosed and treated as early as possible because untreated cases may disseminate to cause visceral involvement with fatal outcome in immunocompromised patients.

Benign acquired superficial skin lesions of the hand

Numerous dermatologic conditions may be visualized by the hand surgeon during office hours, including when examining patients for an alternative chief problem. Although the primary focus of the visit may be unrelated to a skin lesion, it is important for the hand surgeon to be familiar with these lesions to address patient inquiries and determine which lesions may require some form of treatment. This article reviews some of the most common benign acquired superficial skin lesions of the hand. Particular attention will be paid to epidermal lesions, pigmented lesions, vascular lesions, dermal fibrous/fibrohistiocytic lesions, and infections that can be confused with skin neoplasms or tumor-like conditions. Diagnostic clues, including photographs, will be provided for each lesion described, as well as the recommended treatment.

Update on the optimal use of voriconazole for invasive fungal infections

Voriconazole is an extended-spectrum triazole with excellent bioavailability that has now become the treatment of choice for aspergillosis. It has a unique side effect profile compared with other azoles, as well as a number of clinically important drug-drug interactions. These factors, along with a correlation between increased serum levels and improved outcomes, have prompted an interest in therapeutic drug monitoring of this agent. The pharmacology and clinical outcomes data of voriconazole are presented in this review.

Sporotrichosis in Delhi among the migrant population from Uttarakhand, India

Six cases of sporotrichosis in Delhi (non-endemic area) were recorded in migrants from Uttarakhand over a period of one year (2008-2009). The clinico-epidemiological and mycological profile of the patients is discussed. These were confirmed by mycological culture, histopathological examination and/or remission of lesion with potassium iodide. Sporotrichosis is endemic in Uttarakhand, a north-western state in the sub-Himalayan region.

Sporothrix schenckii associated with armadillo hunting in Southern Brazil: epidemiological and antifungal susceptibility profiles

INTRODUCTION: Sporotrichosis is the most common subcutaneous mycosis observed in Brazil and it is generally consequent to a little trauma caused by vegetal particles or spines which inoculate the fungi in the subcutaneous area. Although sporotrichosis had been frequently mentioned with armadillo hunting this form has not been widely reported in Brazil until now. In this study we report ten cases of sporotrichosis evolving the armadillo's hunting diagnosed in some towns located in the central and west regions of Rio Grande do Sul State. METHODS: The cases were established based on clinical and classic mycological laboratorial techniques. The susceptibility tests were conducted by microdilution technique according to M38-A2 CLSI documents. RESULTS: Ten cases of sporotrichosis associated with armadillo hunting detected in the State of Rio Grande do Sul were diagnosed by mycological methods. The susceptibility tests of Sporothrix schenckii isolates to antifungal agents itraconazole, ketoconazole and terbinafine showed that all the isolates were susceptible. CONCLUSIONS: The paper discusses some cultural aspects related to hunting of this wild animal as well as possible causes of this unexpected occurrence in southern Brazil.

Subcutaneous mycoses: chromoblastomycosis, sporotrichosis and mycetoma

Subcutaneous mycoses are common in subtropical and tropical regions of the world. They are rarely observed in Europe. These mycoses are heterogeneous, but all are caused by penetrating trauma of the skin. Most cases in Europe are observed in returning travelers, aid workers, archaeologists and immigrants. Therefore, a careful, thorough history is essential in order to reach a proper diagnosis. We provide up-to-date epidemiological, clinical, diagnostic, and therapeutic data on the three most important imported subcutaneous mycoses in Europe: chromoblastomycosis, sporotrichosis and mycetoma.

Neonatal sporotrichosis

Sporotrichosis is caused by the dimorphic fungus, Sporothrix schenckii. Classically, infection occurs after implantation of the organism into the skin by abrasion of a puncture wound by contaminated thorns, hay, or sphagnum moss. Cats are also a commonly recognized source of sporotrichosis. In children, fixed cutaneous lesions are more common than lymphocutaneous lesions, and the face is a frequent location for infection. We present a neonate with a fixed cutaneous facial lesion and both pre-auricular and cervical lymphadenopathy who developed signs of infection at 3 weeks of age. This patient is currently the youngest reported case of sporotrichosis in the literature. The patient's family denied any trauma and denied contact with flowers, gardens, and cats; thus, the source of infection remains unknown.

Potassium iodide remains the most effective therapy for cutaneous sporotrichosis

Sporotrichosis is a subcutaneous fungal infection caused by the dimorphic fungus Sporothrix schenckii. Itraconazole has largely replaced older therapies, but we present a case of lymphocutaneous sporotrichosis that failed to respond to an adequate course of itraconazole yet responded dramatically to treatment with saturated solution of potassium iodide (SSKI).

Fixed sporotrichosis as a cause of a chronic ulcer on the knee

Chronic wounds are a major health care problem worldwide. Wound healing is a holistic endeavour that requires an accurate identification of the specific entities interfering with wound healing in a particular patient. We present a case of fixed sporotrichosis as the cause of a chronic ulcer in the knee. Although a culture of Sporothrix schenckii could not be obtained, a positive response to the sporotrichin skin test, a skin biopsy showed a suppurative granuloma and an adequate response to oral administration of potassium iodide confirmed the diagnosis. The identification and correction of the underlying aetiology of any chronic wound is the first and most important step to restore wound healing.

Current research on the immune response to experimental sporotrichosis

Sporotrichosis is often manifested as a chronic granulomatous infection and the monocytes/macrophages play a central role in the host defense system. Surface components of Sporothrix schenckii have been characterized and suggestions have been made as to their possible role in pathogenicity. Ergosterol peroxide, cell-wall compounds (alkali-insoluble fraction-F1 and lipid extract-LEY), and exoantigen from the yeast form of the fungus have been characterized as virulence factors, activating both innate, by cytotoxins linked to the activation of reactive oxygen and nitrogen species (H2O2 and NO), and adaptive immune response to produce cytokines Th1 and Th2 profile. In this study, preliminary results have demonstrated that, in systemic sporotrichosis, TLR-4 triggers the innate immune response, activating an oxidative burst. These data represent the first report of the participation of TLR-4 in murine sporotrichosis, in the presence of lipids from the cell wall of S. schenckii. These results taken together may open new perspectives of study leading to an antifungal agent that could be used to benefit the entire population.