RÉSUMÉ
La enfermedad fúngica invasora (EFI) es una de las principales causas de morbimortalidad en los pacientes pediátricos inmunocom- prometidos. Los hongos que con mayor frecuencia causan EFI en este grupo de pacientes corresponden a especies de Candida y Aspergillus. Sin embargo, en los últimos años se ha descrito un aumento de patógenos no clásicos, tales como Fusarium, Scedosporium, Mucorales, Cryptococcus, Trichosporon, entre otros. Se presenta un caso de EFI por Trichosporon asahii en un preescolar con una leucemia linfo- blástica aguda en quimioterapia de inducción. Además, se presenta una revisión actualizada de la literatura especializada, con énfasis en la importancia del diagnóstico precoz y el tratamiento antifúngico específico.
Invasive fungal disease (IFD) is one of the leading causes of morbidity and death among immunosuppressed pediatric patients. The fungi that most frequently cause IFD in this group of patients correspond to Candida and Aspergillus species, however, in recent years an increase in non-classical pathogens, such as Fusarium, Scedosporium, Mucorales, Cryptococcus, Trichosporon, among others. A case of invasive fungal disease caused by Trichosporon asahii is presented in a preschool patient with acute lymphoblastic leukemia in induction stage. This review highlights the importance of active search for pathogens in immunosuppressed patients, and proposes a specific treatment.
Sujet(s)
Humains , Mâle , Enfant d'âge préscolaire , Leucémie-lymphome lymphoblastique à précurseurs B et T/complications , Trichosporonose/complications , Infections fongiques invasives , Trichosporon/isolement et purification , Trichosporonose/diagnostic , Trichosporonose/microbiologie , Trichosporonose/traitement médicamenteux , Antifongiques/usage thérapeutiqueRÉSUMÉ
Bats are important for the homeostasis of ecosystems and serve as hosts of various microorganisms including bacteria, viruses, and fungi with pathogenic potential. This study aimed to isolate fungi from biological samples obtained from bats captured in the city of Sinop (state of Mato Grosso, Brazil), where large areas of deforestation exist due to urbanization and agriculture. On the basis of the flow of people and domestic animals, 48 bats were captured in eleven urban forest fragments. The samples were processed and submitted to microbiological cultures, to isolate and to identify the fungal genera. Thirty-four (70.83%) of the captured bats were positive for fungi; 18 (37.5%) and 16 (33.33%) of these bats were female and male, respectively. Penicillium sp., Scopulariopsis sp., Fusarium sp., Aspergillus sp., Alternaria sp., Cryptococcus sp., Trichosporon sp., and Candida sp., which may cause opportunistic infections, were isolated. The bat species with the highest number of fungal isolates was Molossus molossus: 21 isolates (43.8%). According to our results, bats captured in urban forest fragments in Sinop harbor pathogenic fungi, increasing the risk of opportunistic fungal infections in humans and domestic animals.
Os morcegos apresentam grande importância na homeostasia dos ecossistemas e são hospedeiros de uma rica diversidade de micro-organismos como bactérias, vírus e fungos com potencial patogênico. Portanto, este estudo visou isolar fungos presentes em amostras biológicas de morcegos na cidade de Sinop - MT, que possui grandes áreas de desmatamento devido à urbanização e agricultura. Foram capturados 48 morcegos de diferentes espécies, em onze fragmentos florestais urbanos definidos de acordo com fluxo de pessoas e animais domésticos, para obtenção de amostras biológicas. Essas amostras foram processadas e submetidas aos cultivos microbiológicos, para isolamento e identificação dos gêneros dos fungos. Dos 48 morcegos, 34 (70,83%) foram positivos para pelos menos um gênero de fungo, sendo 18 (37,5%) fêmeas e 16 (33,33%) machos, e os gêneros isolados a partir das amostras biológicas foram Penicillium sp., Scopulariopsis sp., Fusarium sp., Aspergillus sp., Alternaria sp., Cryptococcus sp., Trichosporon sp. e Candida sp., que podem ser causadores de infecções oportunistas. Desse total, a espécie que apresentou maior positividade para pelo menos um gênero de fungo foi Molossus molossus com 21 (43,8%). Nossos resultados demonstram que os morcegos capturados nos fragmentos florestais urbanos na cidade de Sinop - MT, podem atuar como agentes veiculadores de fungos com potencial patogênico, aumentando assim o risco de exposição e aquisição de infecções fúngicas oportunistas por pessoas e animais domésticos.
Sujet(s)
Animaux , Champignons/pathogénicité , Chiroptera/microbiologie , Chiroptera/sang , Alternaria , Aspergillus , Candida , Cryptococcus , Fusarium , Penicillium , Scopulariopsis , TrichosporonRÉSUMÉ
Introducción: Las infecciones de las vías urinarias constituyen una de las patologías infecciosas más frecuentes tanto en la comunidad como en el ámbito hospitalario En el medio hospitalario se ha observado una alta frecuencia de infecciones asociadas a hongos oportunistas, en su mayoría corresponden a especies de Candida spp. Sin embargo, se aíslan otras especies como Trichosporon, donde predomina la especie asahii, en casos de pacientes inmunodeprimidos o con tratamiento previo de antibioticoterapia. Presentación de Casos Clínicos: Se presentan 2 casos donde se aisló en urocultivos Trichosporon asahii. En ambos casos los pacientes presentaron factores de riesgo y síntomas inespecíficos. Conclusión: La presencia de hongos de forma persistente en el tracto urinario es considerada clínicamente significativa. El tratamiento de la funguria debe basarse en el análisis del paciente, de su estado general y de sus factores de riesgo. Para el tratamiento, se observó que el efecto de los triazoles, fueron los más efectivos en el tratamiento de la infección por T. asahii.
Introduction: Urinary tract infections are one of the most frequent infectious pathologies both in the community and in the hospital setting. In the hospital environment, a high frequency of infections associated with opportunistic fungi has been observed, most of which correspond to species of Candida spp. However, other species such as Trichosporon are isolated, where the asahii species predominates (6,7). Presentation of Clinical Cases: Two cases are presented where Trichosporon asahii was isolated in urine cultures. In both cases, the patients presented risk factors and nonspecific symptoms. Conclusion: The persistent presence of fungi in the urinary tract is considered clinically significant (9,10). The treatment of funguria should be based on the analysis of the patient, his general condition and his risk factors (10). For treatment, it was observed that the effect of triazoles was the most effective in the treatment of T. asahii infection (8)
Sujet(s)
Infections urinaires , Trichosporon , InfectionsRÉSUMÉ
Abstract Trichosporon asahii is the causal agent of trichosporonosis. Patients with immunosuppression or hematological malignancies are at higher risk of infection. Skin and mucosal involvement appear as fast-growing papulonodular lesions and necrotic ulcers. Internal organ dissemination is lethal. Therapeutic success depends on the underlying disease. Here, the authors present the first case of disseminated mucocutaneous trichosporonosis in a patient with a post-mortem diagnosis of histiocytic sarcoma, a rare and aggressive haematolymphoid neoplasm. Regretfully, death occurred despite treatment with liposomal amphotericin B and supportive measures, showcasing the fatality of both diseases.
Sujet(s)
Humains , Trichosporon , Sarcome histiocytaire/traitement médicamenteux , Trichosporonose/diagnostic , Trichosporonose/traitement médicamenteux , Basidiomycota , Antifongiques/usage thérapeutiqueRÉSUMÉ
Background: Oleaginous yeasts can be grown on different carbon sources, including lignocellulosic hydrolysate containing a mixture of glucose and xylose. However, not all yeast strains can utilize both the sugars for lipogenesis. Therefore, in this study, efforts were made to isolate dual sugar-utilizing oleaginous yeasts from different sources. Results: A total of eleven isolates were obtained, which were screened for their ability to utilize various carbohydrates for lipogenesis. One promising yeast isolate Trichosporon mycotoxinivorans S2 was selected based on its capability to use a mixture of glucose and xylose and produce 44.86 ± 4.03% lipids, as well as its tolerance to fermentation inhibitors. In order to identify an inexpensive source of sugars, nondetoxified paddy straw hydrolysate (saccharified with cellulase), supplemented with 0.05% yeast extract, 0.18% peptone, and 0.04% MgSO4 was used for growth of the yeast, resulting in a yield of 5.17 g L−1 lipids with conversion productivity of 0.06 g L−1 h−1 . Optimization of the levels of yeast extract, peptone, and MgSO4 for maximizing lipid production using BoxBehnken design led to an increase in lipid yield by 41.59%. FAME analysis of single cell oil revealed oleic acid (30.84%), palmitic acid (18.28%), and stearic acid (17.64%) as the major fatty acids. Conclusion: The fatty acid profile illustrates the potential of T. mycotoxinivorans S2 to produce single cell oil as a feedstock for biodiesel. Therefore, the present study also indicated the potential of selected yeast to develop a zero-waste process for the complete valorization of paddy straw hydrolysate without detoxification
Sujet(s)
Trichosporon/métabolisme , Oryza , Xylose/isolement et purification , Trichosporon/composition chimique , Huiles/composition chimique , Lipogenèse , Biocarburants , Fermentation , Glucose/isolement et purification , Hydrolyse , Lignine/métabolisme , Lipides/biosynthèseRÉSUMÉ
Background: Sugars from sweet sorghum stalks can be used to produce ethanol and also to grow oleaginous yeasts. Instead of two separate processes, in this paper we propose a different route producing ethanol and microbial oil in two consecutive fermentation steps. Results: Three yeasts were compared in the first ethanol producing step. In the second step four different oleaginous yeasts were tested. Sweet sorghum juice was first clarified and concentrated. High gravity ethanol fermentation was carried out with concentrated juice with 23.7 g/100 mL of total sugars and without added nutrients. Total sugars were 2.5 times more than the original clarified juice. One yeast gave the best overall response over the two other tested; relative high ethanol productivity, 1.44 g ethanol/Lâ¢h−1 , and 90% of sugar consumption. Aeration by flask agitation produced superior results than static flasks for all yeasts. Microbial oil production was done employing the residual liquid left after ethanol separation. The pooled residual liquid from the ethanol distillation contained 7.08 g/mL of total carbohydrates, rich in reducing sugars. Trichosporon oleaginosus and Lipomyces starkeyi produced higher dry biomass, total sugar consumption and oil productivity than the other two oleaginous yeasts tested; with values around 25 g/L, 80%, and 0.55 g oil/Lâ¢h−1 respectively. However, the biomass oil content in all yeasts was relatively low in the range of 14 to 16%. Conclusion: The two step process is viable and could be considered an integral part of a consolidated biorefinery from sweet sorghum.
Sujet(s)
Sorghum/composition chimique , Éthanol/métabolisme , Jus de fruits et de légumes , Saccharomyces cerevisiae , Levures , Trichosporon , Sucres , Jus , Lipomyces , Biocarburants/microbiologie , FermentationRÉSUMÉ
Relatar o caso de um paciente com múltiplas trocas valvares aórticas, imunocompetente, com diagnóstico de endocardite fúngica por T. asahii. Relato do caso: Homem, 63 anos, com história de febre reumática e quatro trocas da valva aórtica que evoluiu com sintomas de insuficiência cardíaca aguda e febre. Não foi encontrada nenhuma evidência de imunossupressão. Os exames laboratoriais demonstraram anemia e plaquetopenia leves, com leucograma normal e elevação de lactato desidrogenase e proteína C reativa. O ecocardiograma revelou insuficiência aórtica importante e múltiplas vegetações na valva aórtica. T. asahii foi isolado em duas hemoculturas, sendo iniciada a administração de anfotericina B. O paciente necessitou de cirurgia de emergência para nova troca valvar por deterioração clínica. Em decorrência de complicações intraoperatórias, evoluiu para óbito. Discussão: O diagnóstico e o tratamento da endocardite por T. asahii não estão bem estabelecidos na literatura. Os antifúngicos disponíveis atualmente são triazóis e anfotericina B, com evidências que sugerem superioridade dos triazóis, mas a cirurgia é necessária por ineficácia desses fármacos isoladamente. Conclusões: Faltam dados sobre o tratamento medicamentoso mais eficaz e seguro para a endocardite por T. asahii. Neste caso, as trocas valvares prévias agregaram dificuldade técnica ao novo procedimento, que resultou em evolução desfavorável. Não há dados de literatura sobre o momento ideal para troca valvar em pacientes com múltiplas trocas valvares prévias
To present the case report of an immunocompetent patient with multiple aortic valve replacements, diagnosed with fungal endocarditis due to T. asahii. Case report: A 63-year-old male patient with a history of rheumatic fever and four aortic valve replacements, who progressed with symptoms of acute heart failure and fever. No evidence of immunosuppression was found. Laboratory tests detected mild anemia and thrombocytopenia, with normal leukogram and elevated lactate dehydrogenase and C-reactive protein levels. The echocardiogram revealed severe aortic insufficiency and multiple aortic valve vegetations. T. asahii was isolated in two blood cultures, and administration of amphotericin B was initiated. The patient required emergency surgery for a further valve replacement due to clinical deterioration. The patient later died as a result of intraoperative complications. Discussion: Diagnosis and treatment of T. asahii endocarditis are not well established in the literature. The currently available antifungals are triazoles and amphotericin B, with evidence suggesting superiority of the former, but surgery is required because of the ineffectiveness of these drugs alone. Conclusions: There is insufficient data on the safest and most effective pharmaceutical treatment for T. asahii endocarditis. In this case, the previous valve replacements added technical difficulty to the new procedure, which resulted in an unfavorable outcome. There is no data in the literature on the optimal timing for valve replacement in patients with multiple prior replacements
Sujet(s)
Humains , Mâle , Adulte d'âge moyen , Valve aortique , Trichosporon , Endocardite/mortalité , Immunocompétence , Prothèses et implants , Échocardiographie/méthodes , Facteurs de risque , Électrocardiographie/méthodes , Champignons , Défaillance cardiaque/complicationsRÉSUMÉ
Fungi are a major cause of human infections with diverse clinical manifestations. The incidence of fungal infections has increased over time, particularly in patients who have risk factors such as neutropenia, immune suppression, an intravascular catheter, parenteral nutrition, a prosthetic device, and prior broad spectrum antibiotic therapy. Here, we present an unusual case of co-infection by 2 distinct fungi, Candida parapsilosis and Trichosporon asahii, isolated from a patient who did not have any known risk factors initially, except active pulmonary tuberculosis. Despite the negative conversion of sputum acid-fast bacilli (AFB) culture test after treatment, clinical symptoms were refractory to therapy. The patient developed symptoms suggesting septic shock, and 2 distinct colonies were isolated from a blood specimen, which were identified as C. parapsilosis and T. asahii by MALDI-TOF and rRNA sequencing. Fever and hypotension were relieved after anti-fungal agent injection, and pulmonary lesions identified by imaging also improved.
Sujet(s)
Humains , Candida , Cathéters , Co-infection , Fièvre , Fongémie , Champignons , Hypotension artérielle , Incidence , Neutropénie , Nutrition parentérale , Facteurs de risque , Choc septique , Expectoration , Trichosporon , Tuberculose pulmonaireRÉSUMÉ
Because primary antifungal prophylaxis is widely used for immunocompromised hosts, the incidences of unusual fungal infections have increased. Trichosporon asahii has emerged as an important life-threatening opportunistic systemic pathogen because of the increased use of cytotoxic or immunosuppressant agents, along with high mortality rates. Here, we describe a case of catheter-related T. asahii bloodstream infection with multiple septic skin nodules in both the arms and legs of the patient who was in the neutropenic period after allogeneic stem cell transplantation for myelodysplastic syndrome treated with prophylactic ciprofloxacin and itraconazole. We successfully treated her with intravenous voriconazole for more than a month without any complications. Clinicians should consider breakthrough Trichosporon infections when clinical progress in an immunocompromised patient with unexplained infection signs and symptoms does not improve despite proper treatment with antibiotics or various antifungal agents. In addition, voriconazole can be a good treatment choice for achieving better treatment results and prognosis.
Sujet(s)
Humains , Antibactériens , Antifongiques , Bras , Infections sur cathéters , Ciprofloxacine , Fongémie , Sujet immunodéprimé , Incidence , Itraconazole , Jambe , Mortalité , Syndromes myélodysplasiques , Pronostic , Peau , Transplantation de cellules souches , Trichosporon , VoriconazoleRÉSUMÉ
Because primary antifungal prophylaxis is widely used for immunocompromised hosts, the incidences of unusual fungal infections have increased. Trichosporon asahii has emerged as an important life-threatening opportunistic systemic pathogen because of the increased use of cytotoxic or immunosuppressant agents, along with high mortality rates. Here, we describe a case of catheter-related T. asahii bloodstream infection with multiple septic skin nodules in both the arms and legs of the patient who was in the neutropenic period after allogeneic stem cell transplantation for myelodysplastic syndrome treated with prophylactic ciprofloxacin and itraconazole. We successfully treated her with intravenous voriconazole for more than a month without any complications. Clinicians should consider breakthrough Trichosporon infections when clinical progress in an immunocompromised patient with unexplained infection signs and symptoms does not improve despite proper treatment with antibiotics or various antifungal agents. In addition, voriconazole can be a good treatment choice for achieving better treatment results and prognosis.
Sujet(s)
Humains , Antibactériens , Antifongiques , Bras , Infections sur cathéters , Ciprofloxacine , Fongémie , Sujet immunodéprimé , Incidence , Itraconazole , Jambe , Mortalité , Syndromes myélodysplasiques , Pronostic , Peau , Transplantation de cellules souches , Trichosporon , VoriconazoleRÉSUMÉ
We report the first two cases of Trichosporon mycotoxinivorans infections in Latin America. We also conducted a literature review and a microbiological investigation, including that of clinical and environmental isolates. A 30-year-old man with chronic renal failure had disseminated infection after dialysis and a 15-year-old boy with cystic fibrosis (CF) had pulmonary exacerbations with positive respiratory samples. A review of the relevant literature revealed that deep-seated infections were related to immunosuppression or invasive devices, while most of the CF patients showed a decline in lung function after positive cultures. Phylogenetic analyses revealed three distinct circulating genotypes. MALDI-TOF mass spectrometry analysis showed similar spectral profiles and correctly identified all strains/isolates. Biofilm production was documented in a bloodstream isolate and biofilm-producing cells showed high minimum inhibitory concentrations against antifungals.
Sujet(s)
Humains , Mâle , Adolescent , Adulte , Trichosporon/génétique , Trichosporonose/diagnostic , Trichosporon/classification , Trichosporon/effets des médicaments et des substances chimiques , Brésil/épidémiologie , Tests de sensibilité microbienne , Biofilms/croissance et développement , Trichosporonose/microbiologie , Trichosporonose/épidémiologie , Génotype , Amérique latine , Antifongiques/pharmacologieRÉSUMÉ
La piedra blanca es una micosis superficial crónica y asintomática poco frecuente del pelo causada por Trichosporon spp. (T. asahii, T. cutaneum o T. beigelii, T. inkin y T. mucoides), caracterizada por presentar nódulos blandos, blanquecinos, adheridos a los tallos pilosos, preferentemente del cuero cabelludo, axilas, cejas, pestañas y con menor frecuencia, en la barba, el bigote, el pubis y el perineo. Suele aparecer con mayor frecuencia en población de climas templados y tropicales. En los tres casos reportados se tomó muestra de los cabellos con los nódulos sospechosos, se le realizaron pruebas diagnósticas que permitieron confirmar la presencia de estructuras levaduriformes compatibles con Trichosporon spp. La sospecha de pediculosis es el motivo de consulta de los pacientes con piedra blanca, confundiendo los nódulos con liendres; por consiguiente es importante que el médico tenga claro las enfermedades micóticas con las cuales se debe hacer el diagnóstico diferencial para poder orientar y establecer el adecuado tratamiento para el paciente
The white stone is a rare, superficial, chronic and asymptomatic mycosis of the hair caused by Trichosporon spp. (T asahii, T. cutaneum or T. beigelli, T. inkin, and T. mucoid), which is characterized by the presence of white soft nodules, adhered to the hair shafts, preferably the scalp, armpits, eyebrows, eyelashes, and less frequently, in the beard, moustache, pubic area and perineum. It usually appears with greater frequency in areas of temperate and tropical climates. In the three reported cases, the sample of hair was taken from suspect hair, and then a series of diagnostic tests were performed to allow the confirmation of the presence of yeast shaped structures compatible with Trichosporon spp. Often, a possible pediculosis was the main reason of consultation of the patients who suffer white stone, and it can be confused with nodules of nits. Therefore, it is important that the physician has a better understanding of the fungal diseases that will be part of the differential diagnosis in order to guide and establish a proper treatment for the patients
Sujet(s)
Humains , Femelle , Enfant d'âge préscolaire , Enfant , Adulte , Pediculus , Cuir chevelu , Climat tropical , Trichosporon , Mycoses , Pédiculoses , Volition , Levures , Vibrisses , PoilsRÉSUMÉ
RESUMEN Objetivo Determinar la frecuencia de las dermatomicosis en personas de diferentes instituciones de atención social en la ciudad de Manizales durante el año 2011. Método Mediante la toma de muestras de los sitios que presentaban algún tipo de lesión sospechosa de ser una micosis cutánea, se hizo un análisis directo con KOH y cultivo en medios de Saboureaud y Mycosel. Se aplicó un instrumento de recolección de información para establecer factores asociados con la presencia de estos microorganismos. Resultados Los hongos levaduriformes encontrados con mayor frecuencia fueron: Candida albicans, Trichosporon sp, y los mohos saprofitos Penicillium sp, fusarium sp; seguido de hongos dermatofitos como: Trichophyton mentagrophytes, Trichophyton rubrum, Epidermophyton floccosum y Microsporum gypseum. Las lesiones secas y descamativas se encontraron con mayor frecuencia. El compartir baños y vivir en hacinamiento y el uso de elementos comunes fueron los factores asociados más importantes en este estudio. Conclusiones Las dermatomicosis son frecuentes en poblaciones vulnerables y se asocian a diferentes factores muy similares a los encontrados en otros estudios de igual naturaleza.(AU)
ABSTRACT Objective To determine the frequency of ringworm in people of different social care institutions in the city of Manizales in 2011. Method Using the sampling sites that had some kind of suspicious lesion from a cutaneous mycosis, direct analysis with KOH and culture media was Saboureaud and Mycosel. An instrument of data collection was used to establish factors associated with the presence of these microorganisms. Results The yeast found most frequently were: Candida albicans, Trichosporon sp and Penicillium molds saprophytes sp, Fusarium sp, followed by dermatophyte fungi such as Trichophyton mentagrophytes, Trichophyton rubrum, Epidermophyton floccosum and Microsporum gypseum. Dry scaly lesions were found more frequently. The shared bathrooms and living in overcrowded and the use of common elements were the most important in this study associated factors. Conclusions Dermatomycoses are common in vulnerable populations and are associated with different very similar to those found in other studies of the same nature factors.(AU)
Sujet(s)
Humains , Penicillium/isolement et purification , Trichosporon/isolement et purification , Candida albicans/isolement et purification , Mycoses cutanées/épidémiologie , Épidémiologie Descriptive , Colombie/épidémiologie , Populations vulnérablesRÉSUMÉ
ABSTRACT The antifungal activity of tacrolimus in combination with antifungal agents against different fungal species has been previously reported. Here we report the in vitro interactions between tacrolimus and amphotericin B, fluconazole, itraconazole, and caspofungin against 30 clinical isolates of both fluconazole-susceptible and fluconazole-resistant Trichosporon asahii. For these analyses, we used the broth microdilution method based on the M27-A3 technique and checkerboard microdilution method. Tacrolimus showed no activity against T. asahii strains (minimal inhibitory concentrations, MICs > 64.0 µg mL−1). However, a larger synergistic interaction was observed by the combinations tacrolimus + amphotericin B (96.67%) and tacrolimus + caspofungin (73.33%) against fluconazole-susceptible isolates. Combinations with azole antifungal agents resulted in low rates of synergism for this group (fluconazole + tacrolimus = 40% and itraconazole + tacrolimus = 10%). Antagonistic interactions were not observed. For the fluconazole-resistant T. asahii group, all tested combinations showed indifferent interactions. The synergism showed against fluconazole-susceptible T. asahii isolates suggests that the potential antifungal activity of tacrolimus deserves in vivo experimental investigation, notably, the combination of tacrolimus with amphotericin B or caspofungin.
Sujet(s)
Humains , Trichosporon/effets des médicaments et des substances chimiques , Tacrolimus/pharmacologie , Inhibiteurs de la calcineurine/pharmacologie , Antifongiques/pharmacologie , Tests de sensibilité microbienne , Fluconazole/pharmacologie , Amphotéricine B/pharmacologie , Itraconazole/pharmacologie , Interactions médicamenteuses , Synergie des médicaments , Échinocandines/pharmacologie , Lipopeptides/pharmacologie , CaspofungineRÉSUMÉ
Abstract BACKGROUND: Although dermatophytes are considered the major cause of onychomycosis, many reports have incriminated non-dermatophyte moulds and yeasts in the disease’s etiology. Successive Trichosporon isolation from onychomycosis has led to the genus being suspected as a nail primary pathogen. OBJECTIVE: To determine the prevalence of Trichosporon isolation in onychomycosis patients who attended a mycology diagnostic service in Rio de Janeiro, Brazil, between January 2003 and December 2006. The study also includes a worldwide review on Trichosporon isolation prevalence in ungueal disease, emphasizing T. ovoides. METHODS: This retrospective study was conducted with the support of staff from the Mycology Laboratory at the Dermatological Service of Rio de Janeiro’s Santa Casa da Misericórdia (MLDS). RESULTS: Mycological analysis provided positive results equaling 47/5036 (0.93%) for Trichosporon spp.; obtained mainly as a single agent (72.35%), and from mixed cultures (27.65%; X2= 6.397; p= 0.018). The great majority belongs to the T. ovoides species (91.5%; n=43), obtained as a single isolate (74.41%; n= 32/43; X2 = 7.023; p= 0.014). CONCLUSIONS: Although T. ovoides is classically associated as an etiologic agent of white piedra, this study highlights its potential as a human nail disease pathogen. Our study opens doors for future epidemiologic and virulence factors aimed at determining whether T. ovoides is an important causative agent of onychomycosis in Brazil.
Sujet(s)
Humains , Mâle , Femelle , Adulte d'âge moyen , Sujet âgé , Trichosporon/isolement et purification , Trichosporon/pathogénicité , Onychomycose/microbiologie , Onychomycose/épidémiologie , Brésil/épidémiologie , Numération de colonies microbiennes , Prévalence , Études rétrospectives , Dermatoses du pied/microbiologie , Dermatoses de la main/microbiologieRÉSUMÉ
En este estudio fueron analizadas mediante el cultivo muestras de orina de pacientes hospitalizados en la región centro-oeste de Brasil; los microorganismos aislados fueron identificados filogenéticamente como Trichosporon asahii. A través del análisis de máxima parsimonia de las secuencias de IGS1, fueron encontrados 3 genotipos que no habían sido descritos anteriormente. Las concentraciones inhibitorias mínimas frente a los 9 aislados identificados presentaron un rango de 0,06-1µg/ml en el caso de la anfotericina B, de 0,25-4µg/ml en el del fluconazol, y de 0,03-0,06µg/ml en el del itraconazol. Aproximadamente 6/9 de los aislados de T. asahii formaron biopelículas en la superficie de microplacas de poliestireno. Este trabajo documenta el aislamiento de T. asahii como agente causal de infeciones urinarias nosocomiales. Además, demuestra que la región IGS1 puede ser considerada una nueva herramienta epidemiológica para la genotipificación de los aislados de T. asahii. Los genotipos menos comunes encontrados en este estudio pueden estar relacionados con las características epidemiológicas locales
In this study, the culture analysis of urine samples from patients hospitalized in the Central-West region of Brazil was performed, and the isolated microorganisms were phylogenetically identified as Trichosporon asahii. Maximum parsimony analysis of the IGS1 sequences revealed three novel genotypes that have not been described. The minimum inhibitory concentrations of the nine isolates identified were in the range of 0.061µg/ml for amphotericin B, 0.254µg/ml for fluconazole, and 0.030.06µg/ml for itraconazole. Approximately 6/9 of the T. asahii isolates could form biofilms on the surface of polystyrene microplates. This study reports that the microorganisms isolated here as T. asahii are agents of nosocomial urinary tract infections. Furthermore, the IGS1 region can be considered a new epidemiological tool for genotyping T. asahii isolates. The least common genotypes reported in this study can be related to local epidemiological trends
Sujet(s)
Humains , Mâle , Femelle , Infections urinaires/microbiologie , Trichosporon/isolement et purification , Trichosporon/classification , Tests de sensibilité microbienne/méthodes , Urine/microbiologie , Trichosporonose/épidémiologie , Profil génétiqueRÉSUMÉ
Abstract The Spitzenkörper is a dynamic and specialized multicomponent cell complex present in the tips of hyphal cells. The amphiphilic styryl dye FM4-64 was found to be ideal for imaging the dynamic changes of the apical vesicle cluster within growing hyphal tips. It is widely used as a marker of endocytosis and to visualize vacuolar membranes. Here we performed uptake experiments using FM4-64 to study the dynamic of the Spitzenkörper in Trichosporon asahii. We observed that Spitzenkörpers were present at the tip of the budding site of the spore, blastospore, and the germ tube of T. asahii. We also found that Spitzenkörpers were present at the tip of the hyphae as well as the subapical regions. Cytochalasin D, an inhibitor of actin polymerization, leads to abnormal Spitzenkörper formation and loss of cell polarity.
Sujet(s)
Colorants fluorescents/analyse , Hyphae/cytologie , Organites/métabolisme , Composés de pyridinium/analyse , Composés d'ammonium quaternaire/analyse , Coloration et marquage/méthodes , Trichosporon/cytologie , Trichosporon/croissance et développement , Hyphae/croissance et développement , Microscopie de fluorescenceRÉSUMÉ
Trichosporon asahii es un hongo patógeno emergente reportado en la literatura médica principalmente en pacientes inmunocomprometidos. No obstante, el presente caso es inusual debido a que se trata de un paciente adulto joven inmunocompetente que presentó fungemia por T. asahii y al mismo tiempo desarrolló insuficiencia respiratoria aguda por bronquiolitis respiratoria y neumonía descamativa, la cual resolvió posterior al tratamiento antimicótico instaurado, soporte ventilatorio y vigilancia en Unidad de Cuidado Intesivo (UCI).
Trichosporon asahii is an emerging fungal pathogen reported in the medical literature mainly in immunologically compromised patients. However, this case is unusual because is a young immunocompetent patient who developed fungemia by T. asahii simultaneously with acute respiratory failure, respiratory bronchiolitis and desquamative interstitial pneumonia, who responded satisfactorily to ventilatory support and antifungal therapy.
Trichosporon asahii é um patógeno fúngico emergente relatado na literatura médica principalmente em pacientes imunologicamente comprometidos. No entanto, este caso é incomum porque é um jovem imunocompetente que desenvolveu fungemia por T. asahii simultaneamente com insuficiência respiratória aguda, bronquiolite respiratória e pneumonia intersticial descamativa, que responderam satisfatoriamente ao suporte ventilatório e à terapia antifúngica.