Sporotrichosis

Uncommon aetiology of lymphadenopathy in a healthy child: a sporotrichosis case with painless lymphadenopathy

A 6-year-old boy was referred to the paediatric infectious disease clinic with a 2-month history of enlarged, erythematous, painless cervical lymph nodes. He initially presented to his paediatrician with a painless lesion. At that time, he was treated empirically with clindamycin and azithromycin due to a history of cat exposure. Despite treatment, the lesion evolved into a non-healing linear ulcer with painless, ascending cervical lymphadenopathy. Serologies were negative for Bartonella henselae antibodies. Additional laboratory studies revealed eosinophilia and negative Toxoplasma gondii antibodies. After no improvement following a course of trimethoprim-sulfamethoxazole, further questioning revealed that the patient had fallen into a haystack 1 month before the initial cervical lesion. The patient's parents opted to treat the infection empirically for sporotrichosis with itraconazole rather than undergo lymph node biopsy. At the 2-week follow-up, his lymphadenopathy had resolved and had returned to baseline activity.

Clinical, Epidemiological, and Epizootic Features of Sporothrix brasiliensis in Espírito Santo, Brazil

We verified the clinical-epidemiological, microbiological, and molecular aspects of feline sporotrichosis in Espírito Santo, Brazil, as well as demonstrated the degree of reliability of the cytopathological examination in diagnosis, when compared to fungal culture. From March 2019 to April 2020, 154 suspicious cats were evaluated by collecting data and biological samples. The Cohen's kappa coefficient and the Chi-square independence defined the degree of agreement and the accuracy parameters, respectively. The interobserver agreement was high (Kappa coefficient = 0.96). Sensitivity, specificity, predictive (positive and negative), and accuracy values were 95.0, 97.0, 99.1, 84.2, and 95.5%, respectively. All isolates evaluated were identified as Sporothrix brasiliensis by species-specific PCR. A digital image bank (Padlet) was created with different types of clinical forms and positive slide profiles. We concluded that the cytopathological technique used demonstrated a high degree of reliability. We report an overwhelming occurrence of S. brasiliensis during epizooties in ES.

Microbial Control of Leptopharsa heveae Drake & Poor (Hemiptera: Tingidae) in Brazilian Rubber Tree Plantations: a Brief Historical Account and Identification of Entomopathogenic Fungi by Means of Multigene Phylogeny

Over the last decades, a few fungal species have been mentioned in the literature associated with the rubber tree lace bug, Leptopharsa heveae Drake & Poor (Hemiptera: Tingidae). The rubber plantation area treated with these biocontrol agents has been steady since the 1990s, estimated in 10,000-15,000 ha per year. A few large-scale rubber operations, one biocontrol company, and three government-owned laboratories were, and currently one still is, involved in their commercialization. One species, currently referred to as Sporothrix insectorum, has been historically deployed in biocontrol applications in Brazilian rubber farms. However, L. heveae-infecting isolates have only been identified through morphological examinations; therefore, proper molecular assessments are needed for accurate identifications. Hence, DNA of six L. heveae-infecting isolates (five of which have been deployed in field applications) were extracted and sequenced. Multigene phylogeny found that both Simplicillium lanosoniveum and Cordyceps (formerly Isaria) sp. have been sprayed on rubber plantations to manage L. heveae populations, although the former is the only one currently applied. Simplicillium lanosoniveum and Cordyceps sp. have no relation whatsoever to true Sporothrix species associated with human and animal diseases. Therefore, our molecular data may encourage biocontrol companies to register mycoinsecticides targeting L. heveae. We also added unpublished historical accounts after contacting key contributors to the launching of this not so well-known biocontrol program in the 1980s.

The clinico-epidemiological characteristics and therapeutic experience of 152 patients with cutaneous sporotrichosis: a 10-year retrospective study from India

BACKGROUND

Cutaneous sporotrichosis, a subcutaneous mycosis because of Sporothrix schenckii, is sporadic worldwide with local hyperendemic pockets.

OBJECTIVES

To study clinico-epidemiological and therapeutic aspects of sporotrichosis in our clinic.

METHODS

We retrospectively analyzed medical records of 152 (M:F 52:100) patients with cutaneous sporotrichosis managed during 2010-2019.

RESULTS

All patients were involved in agricultural activities, and 63.2% were aged 21-60 years. Women outnumbered men by nearly two times. Fixed and lymphocutaneous sporotrichosis occurred in 54.6% and 43.4% patients, respectively. Only 2% of patients had multifocal sporotrichosis. Only 48% of patients imputed their disease to prior injuries. Extremities, upper in 53.9% and lower in 21% of patients, were mostly involved. Scrotum involvement in one patient was unusual. A mixed inflammatory infiltrate in 38.7%, chronic granuloma formation in 35%, and presence of spores in 48.9% biopsies was noted. S. schenckii grew on Sabouraud's dextrose agar in 40.2% of cases. Treatment with saturated solution of potassium iodide was curative in 76.8% patients, and lesions healed in 2-9 months (average 5.2 months). Metallic taste was experienced by 42.9% of patients. Itraconazole therapy was safe and effective in seven patients, and the response was better when combined with SSKI compared to either drug used alone.

CONCLUSION

Cutaneous sporotrichosis mostly affects persons during active years of life. The injuries predisposing to infection are mostly forgotten. Both fixed and lymphocutaneous sporotrichosis involving extremities remain common forms. SSKI alone or in combination with itraconazole is safe and effective treatment. Itraconazole is preferable in patients having preexisting hypothyroidism or intolerance to SSKI.

Ocular Sporotrichosis

Purpose

To present 10 cases of Parinaud oculoglandular syndrome caused by sporotrichosis.

Observations

We report 10 cases of Parinaud oculoglandular syndrome after contact with domestic cats diagnosed with sporotrichosis. They all showed ocular hyperemia associated with unilateral tarsal conjunctival granulomas. After histopathological study and culture of the scrapings and conjunctival secretions, six patients were positive for Sporothrix schenkii and four had a presumed diagnosis of Parinaud oculoglandular syndrome due to sporotrichosis. Treatment with 200 mg/day of oral itraconazole was started, and all patients had a favorable therapeutic response.

Conclusion and importance

These case reports are essential for characterizing a rare etiology of Parinaud oculoglandular syndrome.

Serological tests using Sporothrix species antigens for the accurate diagnosis of sporotrichosis: a meta-analysis

Some species of the fungus Sporothrix cause a chronic granulomatous infection in humans and animals called sporotrichosis. In the last decades, some research into serological tests has been carried out by different groups for the rapid detection of this infection. We performed a systematic review of the literature with meta-analysis to evaluate studies using Sporothrix spp. antigens and to evaluate their accuracy for sporotrichosis diagnostic. We searched Scopus, MEDLINE, Web of Science, GALE, Technology Research Database, DOA, Elsevier, SciELO, and Google Scholar Databases. The united results of sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio with their corresponding 95% confidence intervals (CI) were assessed. A total of 15 assays from 8 studies using 7 different serological methods and 8 different antigens were analyzed. The studies were performed in the USA, Brazil, and Venezuela from 1973 until 2015 and presented good quality. A high heterogeneity for sensitivity [I² = 90.7%; 87% CI = (84-89), P < 0.001] and specificity [I² = 89.2%; 93% CI = (92-95), P < 0.001] was observed. The performance of diagnostic tests was 0.93. Enzyme-linked immunosorbent assay was the main tool used, and the ConA-binding fraction antigen of the strain 1099-18 appears as a promising diagnostic biomarker candidate.

Flare or foe? - Mycobacterium marinum infection mimicking rheumatoid arthritis tenosynovitis: case report and literature review

Background

Rheumatoid arthritis is the most common type of inflammatory arthritis affecting about 1% of the population. With the advent of disease-modifying anti-rheumatic drugs the disease can be well controlled in many cases. Patients, however, are prone to developing infectious complications. In rare cases, these can mimic a flare of the underlying itself.

Case presentation

We report the case of a 45-year-old female patient with a history of seronegative rheumatoid arthritis (RA) who presented with swelling and tenderness of the third metacarpophalangeal joint of the right hand. A flare of her RA was suspected based on clinical and ultrasound findings which showed a tenosynovitis with intense power doppler activity. Her steroid dose was increased but the clinical response to glucocorticoid therapy was very limited. Subsequently, she developed skin manifestations of ‘swimmer’s granuloma’ over the next 2 weeks after first presentation. Finally, a diagnosis of a Mycobacterium marinum infection was established with the help of tissue biopsy and culture, and the patient received appropriate antibiotic treatment with the desired effect.

Conclusions

This case highlights the difficulty of distinction between infection and inflammation in patients with joint swelling and pain, especially in the age of disease-modifying drugs (DMARDs) and the concomitant risk of atypical infections. A review of the literature identified eight additional published cases, which suggests that Mycobacterium marinum infection is a rare but recognized complication of DMARD therapy. It can mimic a flare of the underlying arthritis potentially leading to diagnostic delays, and requires differential diagnostic methods to identify the pathogen and pave the way for appropriate treatment.

Endophthalmitis in HIV Infection

Purpose: The role of HIV infection in exogenous and endogenous endophthalmitis has not been clarified. We aim to assess the potential role of HIV as a risk factor or a poor prognostic feature in this sight-threatening condition. Methods: Literature review. Review of evidence: Evidence for endophthalmitis in HIV patients is based on scarce retrospective case series and case reports. Infrequency of literature on this topic is owed to the diversity of the different types of endophthalmitis as well as the rarity of the coexistence of the two conditions. Conclusions: Endophthalmitis in HIV patients are a rare but potentially devastating condition. Many forms of endophthalmitis tend to occur in severely immunosuppressed HIV patients with low CD4 counts. Therefore, the early introduction of cART with full immune reconstitution is an essential part of the prevention of endophthalmitis in the HIV population.

Fast diagnosis of sporotrichosis caused by Sporothrix globosa, Sporothrix schenckii, and Sporothrix brasiliensis based on multiplex real-time PCR

The accurate diagnosis of sporotrichosis and identification at the species level are critical for public health and appropriate patient management. Compared with morphological identification methods, molecular diagnostic tests are rapid and have high sensitivity and standardized operating processes. Therefore, we designed a novel multiplex real-time polymerase chain reaction (PCR) method based on the calmodulin (CAL) gene for the identification of clinically relevant Sporothrix species: S. globosa, S. schenckii s. str., and S. brasiliensis. We evaluated the assay with clinical and spiked samples and assessed its diagnostic performance by comparing the results to those of culture and species-specific PCR. Thirty-three DNA templates were used to detect assay specificity, and three plasmids were constructed to create a standard curve and determine the limits of detection (LODs). For nucleic acid detection, the sensitivity and specificity reached 100%. The LODs were 10 copies, 10 copies and 100 copies for S. globosa, S. schenckii s. str and S. brasiliensis, respectively. For the clinical samples, the positive detection rates by culture, species-specific PCR and the multiplex real-time PCR assay were 87.9% (29/33), 39.4% (13/33), and 93.9% (31/33), respectively. For the spiked samples, the positive detection rates were both 100% for S. schenckii s. str and S. brasiliensis. Based on the above results, compared with culture and other molecular diagnosis methods, the novel multiplex real-time PCR assay is effective, fast, accurate, and highly sensitive. It has a lower reaction cost and lower sample volume requirements, can detect co-infections, and allows for standardized operation and easier interpretation of results. In the future, this assay could be developed into a commercial kit for the diagnosis and identification of S. globosa, S. schenckii s. str, and S. brasiliensis.

Sporotrichosis is a subacute or chronic infectious disease caused by dimorphic fungi of Sporothrix spp. The genus Sporothrix consists of several species with different geographic distributions, virulence, and antifungal susceptibilities, making species-level identification necessary. S. brasiliensis, S. globosa, S. schenckii s. str and S. luriei make up the “pathogenic clade” of the genus Sporothrix. Importantly, S. luriei has a low clinical-epidemiological impact within this genus. Therefore, we designed a novel multiplex real-time PCR method using fluorescent probes for the identification of S. globosa, S. schenckii s. str, and S. brasiliensis. We designed a pair of primers based on the conserved sequence of the calmodulin gene of Sporothrix spp. and probes with different fluorescent signals based on the divergent sequences of S. globosa, S. schenckii s. str and S. brasiliensis. Through the verification of nucleic acid, clinical and spiked sample detection, the multiplex real-time PCR could quickly and accurately identify the three clinically relevant species of Sporothrix spp. with high sensitivity. This new assay could be applied in epidemiology, clinical diagnosis, and experiments with sporotrichosis to control new outbreaks, reduce diagnostic and identification time, and improve test efficiency.

Ploidy Determination in the Pathogenic Fungus Sporothrix spp

The pathogenic clade of the Sporothrix genus comprises the etiological agents of sporotrichosis, a worldwide emergent disease. Despite the growing understanding of their successful pathogen traits, there is little information on genome sizes and ploidy within the genus. Therefore, in this work, we evaluated the ploidy of four species of the Sporothrix genus, specifically Sporothrix brasiliensis, Sporothrix schenckii, Sporothrix globosa, and Sporothrix pallida. Through cell cycle analysis of the yeast-phase cells, we showed that the DNA content of G0/G1 cells was similar to the genome size determined by whole genome sequencing. Moreover, ploidy of S. schenckii, S. brasiliensis, and S. pallida that was determined by allele composition using next-generation sequencing (NGS) data is consistent with monomorphic positions at each allele. These data show that the analyzed strains of Sporothrix are haploid, or at least aneuploid, thereby laying the foundation for the development of a molecular toolbox for Sporothrix spp.

Sporotrichosis In Immunocompromised Hosts

Sporotrichosis is a global implantation or subcutaneous mycosis caused by several members of the genus Sporothrix, a thermo-dimorphic fungus. This disease may also depict an endemic profile, especially in tropical to subtropical zones around the world. Interestingly, sporotrichosis is an anthropozoonotic disease that may be transmitted to humans by plants or by animals, especially cats. It may be associated with rather isolated or clustered cases but also with outbreaks in different periods and geographic regions. Usually, sporotrichosis affects immunocompetent hosts, presenting a chronic to subacute evolution course. Less frequently, sporotrichosis may be acquired by inhalation, leading to disseminated clinical forms. Both modes of infection may occur in immunocompromised patients, especially associated with human immunodeficiency virus (HIV) infection, but also diabetes mellitus, chronic alcoholism, steroids, anti-TNF treatment, hematologic cancer and transplanted patients. Similar to other endemic mycoses caused by dimorphic fungi, sporotrichosis in immunocompromised hosts may be associated with rather more severe clinical courses, larger fungal burden and longer periods of systemic antifungal therapy. A prolonged outbreak of cat-transmitted sporotrichosis is in progress in Brazil and potentially crossing the border to neighboring countries. This huge outbreak involves thousands of human and cats, including immunocompromised subjects affected by HIV and FIV (feline immunodeficiency virus), respectively. We reviewed the main epidemiologic, clinical, diagnostic and therapeutic aspects of sporotrichosis in immunocompromised hosts.

Isolated Sporothrix schenckii Monoarthritis

Sporothrix schenkii sensu lato is a rare cause of arthritis. Its course is indolent with lack of constitutional symptoms resulting in delayed presentation and diagnosis. It is a dimorphic fungus found ubiquitously in sphagnum moss, decaying vegetation, soil, and hay. Inoculation of dirt into the skin and soft tissues and, in rare instances, inhalation of aerosolized conidia from soil and plants can lead to infection. Subacute and chronic involvement of skin and subcutaneous tissues is the most common manifestation of sporotrichosis in immunocompetent hosts. In patients with underlying risk factors (HIV, alcoholism, diabetes mellitus, organ transplant patients, immunosuppressive medications, steroids, and malignancies), it can often have disseminated visceral, osteoarticular, meningeal, and pulmonary involvement. Sporothrical arthritis most commonly infects knee joint followed by hand and wrist joints. A culture of Sporothrix schenkii sensu lato is the gold standard for the diagnosis of sporotrichosis. Itraconazole is the drug of choice for osteoarticular sporotrichosis. We present a case of sporotrichal arthritis in a patient without skin or lymph node involvement who underwent treatment with itraconazole resulting in resolution of his symptoms.

Proteins Potentially Involved in Immune Evasion Strategies in Sporothrix brasiliensis Elucidated by Ultra-High-Resolution Mass Spectrometry

Sporotrichosis is an important disease in Brazil that is caused by fungi of the genus Sporothrix and affects cats and humans. Our work investigated the proteins differentially expressed by S. brasiliensis in order to find out why this species is more virulent and pathogenic than S. schenckii. We verified a set of proteins that may be related to immune escape and that can explain the high virulence.

Sporothrix brasiliensis is the prevalent agent of a large zoonotic outbreak in Brazil. With the involvement of several thousands of cases, this is the largest cohort of human and animal sporotrichosis on record in the world. Infections are characterized by local cutaneous dissemination in humans without underlying disease. S. brasiliensis has shown a high degree of virulence in a mouse model compared to the remaining Sporothrix species, including the ancestral species, Sporothrix schenckii. The present paper investigates a genomic and expressed-proteome comparison of S. brasiliensis to S. schenckii. Using bottom-up proteomics, we found 60 proteins exclusively expressed in S. brasiliensis. No significant genomic differences were found among the genes coding for this protein set. A comparison with literature data identified nine proteins that are known to be involved in virulence and immune evasion in other species, several of which had not yet been reported for the Sporothrix species analyzed.

IMPORTANCE Sporotrichosis is an important disease in Brazil that is caused by fungi of the genus Sporothrix and affects cats and humans. Our work investigated the proteins differentially expressed by S. brasiliensis in order to find out why this species is more virulent and pathogenic than S. schenckii. We verified a set of proteins that may be related to immune escape and that can explain the high virulence.

Sporothrix schenckii Immunization, but Not Infection, Induces Protective Th17 Responses Mediated by Circulating Memory CD4+ T Cells

Sporotrichosis is a chronic subcutaneous mycosis caused by the Sporothrix schenckii species complex and it is considered an emerging opportunistic infection in countries with tropical and subtropical climates. The host’s immune response has a main role in the development of this disease. However, it is unknown the features of the memory cellular immune response that could protect against the infection. Our results show that i.d. immunization in the ears of mice with inactivated S. schenckii conidia (iC) combined with the cholera toxin (CT) induces a cellular immune response mediated by circulating memory CD4⁺ T cells, which mainly produce interleukin 17 (IL-17). These cells mediate a strong delayed-type hypersensitivity (DTH) reaction. Systemic and local protection against S. schenckii was mediated by circulating CD4⁺ T cells. In contrast, the infection induces a potent immune response in the skin mediated by CD4⁺ T cells, which have an effector phenotype that preferentially produce interferon gamma (IFN-γ) and mediate a transitory DTH reaction. Our findings prove the potential value of the CT as a potent skin adjuvant when combined with fungal antigens, and they also have important implications for our better understanding of the differences between the memory immune response induced by the skin immunization and those induced by the infection; this knowledge enhances our understanding of how a protective immune response against a S. schenckii infection is developed.

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.

Sporotrichal Tenosynovitis Diagnosed Helpfully by Musculoskeletal Ultrasonography

A 72-year-old man presented with persistent oligoarthritis and positive results for rheumatoid factor and was suspected of having rheumatoid arthritis (RA). However, the musculoskeletal ultrasonography (MSUS) findings were not consistent with those of typical RA. He had undergone surgery for carpal tunnel syndrome, which allowed both histopathological and microbiological examinations to be performed. A synovial tissue culture was positive for Sporothrix schenckii, and he was diagnosed with sporotrichal tenosynovitis. He received anti-fungal therapy, and the sporotrichal tenosynovitis resolved. This case suggests that MSUS is a useful modality, and sporotrichal tenosynovitis, though rare, should be considered in the differential diagnosis of RA.

Lower percentage of CD8+ T cells in peripheral blood of patients with sporotrichosis

PURPOSE

To characterize the peripheral immunity and immunity response of patients with sporotrichosis, in this study we determined the lymphocyte subsets in the peripheral blood of Chinese patients with sporotrichosis.

METHODS

In this retrospective study, peripheral blood was collected from 69 sporotrichosis patients (37, fixed cutaneous form; 32 lymphocutaneous) and 66 healthy controls. Lymphocyte subsets were analyzed using flow cytometry.

RESULTS

Compared to controls, the percentage of CD8+ T cells was lower in sporotrichosis patients. The percentage of CD8+ T cells in peripheral blood tended to become lower with disease duration and disease severity, although the difference was not statistically significant for either acute, subacute and chronic patients or fixed cutaneous and lymphocutaneous patients.

CONCLUSION

Our data indicate that the decrease of CD8+ T cells in peripheral blood of patients with sporotrichosis is associated with disease severity, although the difference was not statistically significant for either duration or clinical forms of the disease. Combining antifungal agents and immunomodulators in patients with long disease duration and lymphocutaneous may be more beneficial than antifungal monotherapy.

Primary Cutaneous Nocardiosis in a Patient With Nephrotic Syndrome: A Case Report and Review of the Literature

Nocardia infection is not common in clinical practice and most cases occur as an opportunistic infection in immunocompromised patients.We report a case of primary cutaneous nocardiosis characterized by multiple subcutaneous abscesses due to Nocardia brasiliensis in a patient with nephrotic syndrome undergoing long-term corticosteroid therapy. The patient was diagnosed with nephrotic syndrome 9 months ago, and mesangial proliferative glomerulonephritis was confirmed by renal biopsy. Subsequently, his renal disease was stable under low-dose methylprednisolone (8 mg/d). All of the pus cultures, which were aspirated from 5 different complete abscesses, presented Nocardia. Gene sequencing confirmed that they were all N. brasiliensis. The patient was cured by surgical drainage and a combination of linezolid and Trimethoprim-Sulfamethoxazole.The case highlights that even during the period of maintenance therapy with low-dose corticosteroid agents, an opportunistic infection still could occur in patients with nephrotic syndrome.

Subcutaneous mycoses in coastal Karnataka in south India

BACKGROUND

Subcutaneous mycoses are chronic, localized infections of the skin and subcutaneous tissue which occur following traumatic implantation of the etiological agent. The causative organisms are soil saprophytes of regional epidemiology with varying ability to adapt to the tissue environment and elicit disease.

OBJECTIVES

This study was conducted to evaluate the various types of subcutaneous mycoses, including actinomycotic mycetomas, in south coastal Karnataka, India.

METHODS

Between January 2005 and January 2013, a total of 25 patients were diagnosed with subcutaneous mycoses based on a detailed clinical history and presentation, histopathology, and culture of organisms.

RESULTS

Chromoblastomycosis was the infection most commonly seen (n = 16 patients, 64%), followed by mycetoma (n = 4, 16%), sporotrichosis (n = 4, 16%), and rhinoentomophthoromycosis (n = 1, 4%). The extremities were the most common site of involvement, with the lower limb being most affected (64%). Males were more commonly afflicted (64%) than females (36%). Most patients were agricultural workers, although preceding trauma was noted in only three patients. The majority of patients responded well to therapy and were disease-free on follow-up.

CONCLUSIONS

Subcutaneous mycoses are a rare group of disorders. Chromoblastomycosis is the most frequent subcutaneous fungal infection in south India. Morphologically, chromomoblastomycoses present as verrucous, ulcerative, nodular, or eczematous lesions. Clinical diagnosis is important as culture is often negative. The incidence of infection is higher among rubber tappers. It is important to clinically differentiate chromoblastomycosis from tuberculosis verrucosa cutis. Most of the subcutaneous mycoses respond well to treatment, with the exception of rhinoentomophthoromycosis, which is a rare form of deep mycosis with associated mutilation. Eumycetomas are not observed in this part of India.

Molecular epidemiology of human sporotrichosis in Venezuela reveals high frequency of Sporothrix globosa

Background

Sporotrichosis is a cutaneous and subcutaneous fungal disease of humans and other mammals, known to be caused by the Sporothrix schenckii species complex, which comprises four species of clinical importance: S. brasiliensis, S. globosa, S. luriei, and S. schenckii sensu stricto. Of them, S. globosa and S. schenckii s. str. show global distribution and differences in global frequency as causal agents of the disease. In the Americas, only three species are present: S. schenckii s. str., S. brasiliensis (so far, only reported in Brazil), and S. globosa. In Venezuela, since the first case of sporotrichosis reported in 1935, S. schenckii have been considered its unique etiological agent. In the present work, the presence of more than one species in the country was evaluated.

Methods

By phenotypic key features and molecular phylogeny analyses, we re-examined 30 isolates from diverse Venezuelan regions belonging to the fungi collection of Instituto de Biomedicina, Caracas, Venezuela, and national reference center for skin diseases. All isolates were collected between 1973 and 2013, and maintained in distilled water.

Results

Sporotrichosis in Venezuela is mainly caused by S. schenckii s. str. (70%). However, a significant proportion (30%) of sporotrichosis cases in the country can be attributable to S. globosa. A correlation between intraspecific genotypes and clinical presentation is proposed.

Conclusions

Our data suggest that sporotrichosis various clinical forms might be related to genetic diversity of isolates, and possibly, to diverse virulence profiles previously reported in the S. schenckii species complex. Sporothrix globosa was found to be the causative agent of 30% of sporotrichosis for the Venezuelan cases re-examined, the highest frequency of this species so far reported in the Americas. The high genetic variability presented by S. schenckii s. str. indicates that species distinction based on phenotypic key features could be a challenging and uncertain task; molecular identification should be always employed.

The impact of sporotrichosis in HIV-infected patients: a systematic review

Sporotrichosis is a fungal infection of man and animals caused by Sporothrix complex. It usually presents as a lymphocutaneous form, but disseminated disease may occur. Given the paucity of data about HIV/AIDS and sporotrichosis co-infection, a systematic review of reported cases of HIV-associated sporotrichosis found via Pubmed (1984-2013) was done. A total of 39 papers were included, and 58 patients' data analyzed. Thirty-three (56.9 %) cases were from Brazil and 18 (31 %) from the USA. Patients' mean age was 37.8 ± 10.4 years; males predominated (84.5 %). The median CD4(+) cell count was 97 cells/mm(3). The most common clinical forms were disseminated and disseminated cutaneous with 33 (56.9 %) and 10 (17.5 %) patients, respectively. There was a correlation between CD4(+) count and clinical categories (p = 0.002). Mortality was 30 % and there was a correlation between central nervous system involvement and death (p < 0.001).

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.

Sporothrix schenckii complex biology: environment and fungal pathogenicity

Sporothrix schenckii is a complex of various species of fungus found in soils, plants, decaying vegetables and other outdoor environments. It is the aetiological agent of sporotrichosis in humans and several animals. Humans and animals can acquire the disease through traumatic inoculation of the fungus into subcutaneous tissue. Despite the importance of sporotrichosis, it being currently regarded as an emergent disease in several countries, the factors driving its increasing medical importance are still largely unknown. There have only been a few studies addressing the influence of the environment on the virulence of these pathogens. However, recent studies have demonstrated that adverse conditions in its natural habitats can trigger the expression of different virulence factors that confer survival advantages both in animal hosts and in the environment. In this review, we provide updates on the important advances in the understanding of the biology of Spor. schenckii and the modification of its virulence linked to demonstrated or putative environmental factors.

Use of potassium iodide in dermatology: updates on an old drug

Potassium iodide, as a saturated solution, is a valuable drug in the dermatologist's therapeutic arsenal and is useful for the treatment of different diseases due to its immunomodulatory features. However, its prescription has become increasingly less frequent in dermatology practice. Little knowledge about its exact mechanism of action, lack of interest from the pharmaceutical industry, the advent of new drugs, and the toxicity caused by the use of high doses of the drug are some possible explanations for that. Consequently, there are few scientific studies on the pharmacological aspects, dosage and efficacy of this drug. Also, there is no conventional standard on how to manipulate and prescribe the saturated solution of potassium iodide, which leads to unawareness of the exact amount of the salt being delivered in grams to patients. Considering that dosage is directly related to toxicity and the immunomodulatory features of this drug, it is essential to define the amount to be prescribed and to reduce it to a minimum effective dose in order to minimize the risks of intolerance and thus improve treatment adherence. This review is relevant due to the fact that the saturated solution of potassium iodide is often the only therapeutic choice available for the treatment of some infectious, inflammatory and immune-mediated dermatoses, no matter whether the reason is specific indication, failure of a previous therapy or cost-effectiveness.

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.

Mouse bone marrow-derived dendritic cells can phagocytize the Sporothrix schenckii, and mature and activate the immune response by secreting interleukin-12 and presenting antigens to T lymphocytes

In sporotrichosis, dermal dendritic cells were considered to participate in induction of the immune responses against Sporothrix schenckii infection. However, it is still unclear whether and how dermal dendritic cells were involved in the progress. To clarify the pathogenic role of dermal dendritic cells (DC) in sporotrichosis, we examined the phagocytosis, maturation stages, cytokine production and antigen-presenting ability of mouse bone marrow-derived DC after stimulation with S. schenckii. By analysis of flow cytometry, electron microscope and confocal microscope, mouse bone marrow-derived DC were proved to be able to phagocytize the S. schenckii. The increased expression of CD40, CD80 and CD86 on the surface of S. schenckii-pulsed mouse bone marrow-derived DC was detected by flow cytometer, indicating that the S. schenckii-pulsed mouse bone marrow-derived DC underwent the maturation program. The secretory enhancement of interleukin (IL)-12, but not IL-4, was found in S. schenckii-pulsed mouse bone marrow-derived DC, suggesting the possible activation of T-helper 1 prone immune responses. Furthermore, S. schenckii-pulsed mouse bone marrow-derived DC were demonstrated to be capable of inducing the proliferation of T lymphocytes from BALB/c mice that were pre-sensitized with S. schenckii. Together, all the results implied that dermal DC may participate in the induction of immune responses against S. schenckii infection in sporotrichosis.

Influence of TLR-2 in the immune response in the infection induced by fungus Sporothrix schenckii

Toll-like receptors (TLRs) play an important role in immunity, since they bind to pathogen surface antigens and initiate the immune response. However, little is known about the role of TLR-2 in the recognition of S. schenckii and in the subsequent immune response. Therefore, the aim of this study was to evaluate the involvement of TLR-2 in the immune response induced by S. schenckii. C57BL/6 mice (WT) and C57BL/6 TLR-2 knockout (TLR-2-/-) were used to evaluate, over a period of 10 weeks of sporotrichotic infection, the influence of TLR-2 over macrophages production of IL-1β, IL-12 and TNF-α, their stimulation level by NO release and the production of IFN -γ, IL-6, IL-17 and TGF-β by spleen cells. The results showed that the production of pro-inflammatory mediators and NO, TLR-2 interference is striking, since its absence completely inhibited it. IL-17 production was independent of TLR-2. The absence of Th1 response in TLR2-/- animals was concomitant with IL-17 production. Therefore, it can be suggested that TLR-2 absence interferes with the course of the infection induced by the fungus S. schenckii.

Sporotrichosis: a forgotten disease in the drug research agenda

Potassium iodide was discovered in the 19th century and still remains as one of the more effective and most prescribed treatments for sporotrichosis. No new drugs have been evaluated in large randomized clinical trials in comparison with standard or alternative treatments for sporotrichosis during the last decades. The emergence of disseminated sporotrichosis in AIDS patients has uncovered the need for more effective treatments. Sporotrichosis is only a public health problem in a few geographical areas, mostly located in developing countries; and its usually harmless history could explain the limited investment in sporotrichosis treatment research. Better understanding of the virulence factors, such as the melanization process, could reveal new potential drug targets.

Epidemiology of sporotrichosis in Venezuela

BACKGROUND

Sporotrichosis is one of the most common subcutaneous mycoses in Venezuela. It is a granulomatous chronic infection with cutaneous or subcutaneous tissue lesions. Regional lymphatic involvement may be present; extracutaneous disease is rare. The causal fungus Sporothrix schenckii has been isolated from soil, vegetation, and animals on numerous occasions and in many localities throughout the world. The aim of this study is to describe clinical and epidemiological features of cases of sporotrichosis observed in Venezuela and review of the literature.

PATIENTS AND METHODS

We included the demographic data, clinical features, diagnostic methods, treatment, and follow-up of patients with sporotrichosis from 1963 to 2009, diagnosed at the Department of Medical Mycology.

RESULTS

One-hundred and thirty-three sporotrichosis cases were diagnosed. Most patients were under the age of 30 years (66.15%). In 61.6% of them, the mode of transmission was not identified. The predominant clinical form in this population was lymphocutaneous (63.15%). Direct microscopic diagnosis was performed in 123 cases, and 57.9% yielded positive results for asteroid body.

CONCLUSIONS

Sporotrichosis is an endemic subcutaneous mycosis in Venezuela. There are no reports to this date of disseminated forms of the disease, even amongst patients with acquired immunodeficiency syndrome. Direct microscopic examination of wet mount slides with saline solution or distilled water in the search for asteroid bodies is paramount. Saturated sodium and potassium iodine solutions continue to be extremely efficacious and affordable to most of our patients, therefore our treatment of choice.