A case of disseminated subcutaneous phaeohyphomycosis caused by Exserohilum rostratum with CARD9 mutation

Phaeohypomycosis is a rare cutaneous and subcutaneous fungal infection caused by dematiaceous fungi. They have a widespread global distribution occasionally affecting humans. A 26-year-old woman presented with multiple skin lesions over her face and extremities for last 7 years, unresponsive to systemic amphotericin B and itraconazole. Further investigations revealed CARD9 mutation and phaeohyphomycosis caused by the pigmented fungus Exserohilum rosatratum. Lesions subsequently improved with oral flucytosine and itraconazole

Feohifomicosis por Exserohilum rostratum en un paciente pediátrico con leucemia linfoblástica aguda postransplante de médula ósea / Phaeohyphomycosis by Exserohilum rostratum in a pediatric patient with acute lymphoblastic leukemia after bone marrow transplantation

Resumen El género Exserohilum corresponde a hongos dematiáceos, la mayoría fitopatógenos, saprobios, de los cuales solo tres especies serían patógenas para el hombre: Exserohilum rostratum, Exserohilum longirostratum y Exserohilum mcginnisii. Se han reportado infecciones localizadas y sistémicas causadas por estos agentes, tanto en pacientes inmunocompetentes como inmunosuprimidos. Se presenta un caso de infección cutánea por E. rostratum en un paciente pediátrico con inmunocompromiso.

Abstract The genus Exserohilum consists of dematiaceous or darkly pigmented fungi. Most of the species included in this genus are phytopathogens, saprobes and only three of these species would be pathogenic to humans: Exserohilum rostratum, Exserohilum longirostratum and Exserohilum mcginnisii. Localized and systemic infections have been reported both in immunocompetent and immunosuppressed patients. A clinical case of cutaneous infection by E. rostratum in an immunocompromised pediatric patient is presented in this study.

Infección rino-sinusal por Exserohilum rostratum en un niño con leucemia mieloide aguda / Sinus infection caused by Exserohilum rostratum in a pediatric patient with acute myeloid leukemia

Resumen Los episodios de neutropenia febril son cuadros graves, que requieren un estudio etiológico exhaustivo y un inicio rápido de antimicrobianos. Dentro de los posibles microorganismos causales se encuentran los de origen fúngico, los que, dependiendo de su grado de invasión tisular, pueden llegar a presentar una alta mortalidad. Presentamos el caso de un niño con una leucemia mieloide aguda, que tras su quimioterapia de inducción, presentó un episodio de neutropenia febril, con una infección rino-sinusal por Exserohilum rostratum, hongo filamentoso que raramente se asocia a cuadros patológicos. Se inició rápidamente terapia antifúngica, lo cual, asociado a un aseo quirúrgico precoz, lograron una respuesta clínica favorable, sin complicaciones. Luego del seguimiento, y tras recibir profilaxis secundaria durante los episodios de neutropenia, no ha vuelto a presentar nuevas lesiones ni compromiso rino-sinusal.

Abstract The episodes of febrile neutropenia are severe cases that require an exhaustive etiological study and a quick start of antimicrobial agents. Within the possible microorganisms, fungal origins are also found, and depending on its tissue invasion, they can reach a high mortality rate. A case of a pediatric patient who suffered from acute myeloid leukemia is reported, and after his induction chemotherapy, the patient showed an episode of febrile neutropenia, which matches a rhinosinusal infection caused by Exserohilum rostratum, a filamentous fungi that is uncommonly associated with pathological cases. An antifungal therapy and an early surgical treatment were started, which lead to a positive response, without complications to the patient. After the monitoring and receiving secondary prophylaxis during the episodes of neutropenia, the patient hasn't presented new injuries nor rhinosinusal damage.

Microbiological And Epidemiological Profile Of Keratomycosis In A Tertiary Care Hospital – A Prospective Analysis

Introduction: Microbial keratitis is predominantly an opportunistic, serious ocular infectious disease that can lead to significant vision loss and ophthalmic morbidity.1 The fungi are significant pathogens causing ocular infections due to their frequent involvement and difficulty in establishing definitive diagnosis.. Material and Methods: We prospectively analyzed 106 cases of keratomycosis in our tertiary care hospital. Corneal scrapings were collected, processed and fungal pathogens were identified by standard laboratory techniques. Results: Out of 106 suspected cases, culture was positive in 31 cases. Aspergillus species were the most frequent isolates (51.61%). Next to this were Candida spp. (19.35%) followed by Fusarium spp., Alternaria spp., Mucor spp , Penicillium spp, Drechslera spp and Exserohilum spp . Males were more affected than females and trauma was the most common predisposing factor. Conclusions: This study highlights important risk factors and organisms responsible for mycotic keratitis.

Exserohilum keratitis: Clinical profile of nine patients and comparison of morphology versus ITS-Based DNA sequencing for species identification of the fungal isolates

Purpose: The objective of this study was to describe the microbiological and clinical features of nine cases of Exserohilum keratitis. Patients and Methods: Fungal isolates from corneal scrapings were identified based on macroscopic and microscopic characteristics of the colonies and DNA sequencing of ITS1-5.8S-ITS2 region in the rRNA gene. All patients were treated with topical and if required systemic antifungals. Therapeutic penetrating keratoplasty (TPK) was done in case of failed medical therapy. Results: Morphologically, all fungal isolates were Exserohilum rostratum except one Exserohilum mcginnisii. Based on the BLAST analysis, 6 isolates showed 100% similarity to Setosphaeria rostrata (CBS 112815) and E. mcginnisii (CBS 20308). The other three isolates were Setosphaeria holmii (CBS 128053), not reported earlier in fungal keratitis. Three patients were lost to follow-up and response to medical therapy was good (Healed scar � 4 patients). Two out of nine patients were advised TPK. Conclusions: Diagnosis and clinical features of Exserohilum keratitis are akin to other dematiaceous keratitis. The two morphological species of E. mcginnisii and E. rostratum are indistinguishable from Setosphaeria rostratum at DNA sequence level, which justifies the retention of the latter nomenclature.

Sinusitis aguda invasiva por Exserohilum rostratum en una paciente pediátrica con recaída medular de leucemia linfoblástica aguda / Invasive acute sinusitis by Exserohilum rostratum in a patient with medullary relapse of acute lymphoblastic leukemia

La infección fúngica invasora ha aumentado en frecuencia a lo largo de la última década, y la sinusitis fúngica es cada vez más habitual. Los hongos del género Exserohilum (familia Pleosporaceae, orden Pleosporales) son filamentosos y dematiáceos, de localización ubicua. Se trata de patógenos emergentes, que producen, en la mayoría de los casos, infecciones sistémicas que afectan, principalmente, a los senos paranasales y los pulmones. Son más frecuentes en pacientes inmunosuprimidos, aunque pueden presentarse en pacientes inmunocompetentes. El tratamiento de estas infecciones comprende el tratamiento antifúngico, resección quirúrgica y restitución de la inmunidad. Se presenta el caso de una paciente con recaída medular de leucemia linfoblástica aguda con sinusitis fúngica invasiva por Exserohilum rostratum.

Invasive fungal infection has increased in frequency over the last decade, with fungal sinusitis becoming more frequent. The fungi of the genus Exserohilum (family Pleosporaceae, order Pleosporales) are filamentous and dematiaceous of ubiquitous location. It is an emerging pathogen, which in most cases produces a systemic infection that mainly affects the paranasal sinuses and lungs. It is more common in immunosuppressed patients, although it may occur in immunocompetent patients. The treatment is based on three pillars: antifungal treatment, surgical debridement and restitution of immunity. We present the case of a patient with medullary relapse of acute lymphoblastic leukemia with invasive fungal sinusitis by Exserohilum rostratum.

Efficacy of epiphytic bacteria to prevent northern leaf blight caused by Exserohilum turcicum in maize / Eficacia de bacterias epifíticas en la prevención del tizón foliar del maíz causado por Exserohilum turcicum

Eight potential biological control agents (BCAs) were evaluated in planta in order to assess their effectiveness in reducing disease severity of northern leaf blight caused by Exserohilum turcicum. The assay was carried out in greenhouse. Twenty-six-day-old plants, V4 phenological stage, were inoculated with antagonists by foliar spray. Only one biocontrol agent was used per treatment. Ten days after this procedure, all treatments were inoculated with E. turcicum by foliar application. Treatments performed were: C-Et: control of E. turcicum; T1: isolate 1 (Enterococcus genus) + E. turcicum; T2: isolate 2 (Corynebacterium genus) + E. turcicum; T3: isolate 3 (Pantoea genus) + E. turcicum; T4: isolate 4 (Corynebacterium genus) + E. turcicum; T5: isolate 5 (Pantoea genus) + E. turcicum; T6: isolate 6 (Bacillus genus) + E. turcicum; T7: isolate 7 (Bacillus genus) + E. turcicum; T8: isolate 8 (Bacillus genus) + E. turcicum. Monitoring of antagonists on the phyllosphere was performed at different times. Furthermore, the percentage of infected leaves and, plant and leaf incidence were determined. Foliar application of different bacteria significantly reduced the leaf blight between 30-78% and 39-56% at 20 and 39 days respectively. It was observed that in the V10 stage of maize plants, isolate 8 (Bacillus spp.) caused the greatest effect on reducing the severity of northern leaf blight. Moreover, isolate 8 was the potential BCA that showed more stability in the phyllosphere. At 39 days, all potential biocontrol agents had a significant effect on controlling the disease caused by E. turcicum.

Se evaluó a 8 potenciales agentes de control biológico (ACB) en un ensayo in planta, con el objetivo de probar su efectividad en la reducción del daño provocado por Exserohilum turcicum, agente causal del tizón foliar del maíz. El ensayo se llevó a cabo en invernadero. Plantas de maíz de 26 días, en estadio fenológico V4, se inocularon con los potenciales antagonistas por aplicación foliar como espray. Solo un agente de biocontrol fue usado por tratamiento y todos los tratamientos se inocularon con E. turcicum 10 días después, también por aplicación foliar. Los tratamientos desarrollados fueron los siguientes: C-Et: control de E. turcicum; T1: aislamiento 1 (género Enterococcus) + E. turcicum; T2: aislamiento 2 (género Corynebacterium) + E. turcicum; T3: aislamiento 3 (género Pantoea) + E. turcicum; T4: aislamiento 4 (género Corynebacterium) + E. turcicum; T5: aislamiento 5 (género Pantoea) + E. turcicum; T6: aislamiento 6 (género Bacillus) + E. turcicum; T7: aislamiento 7 (género Bacillus) + E. turcicum; T8: aislamiento 8 (género Bacillus) + E. turcicum. La monitorización en la filosfera de los antagonistas se llevó a cabo a diferentes tiempos. Además, se determinó el porcentaje de hojas infectadas y la incidencia en plantas y hojas. La aplicación foliar de diferentes bacterias redujo significativamente la gravedad del tizón del maíz: entre el 30 y el 78% a los 20 días y entre el 39 y el 56% a los 39 días. En el estadio V10 de las plantas de maíz se observó que el aislamiento 8 (Bacillus spp.) causó el mayor efecto de reducción del tizón foliar. Además, dicho aislamiento fue el potencial agente de biocontrol que mostró mayor estabilidad en la filosfera. A los 39 días, todos los potenciales agentes de biocontrol demostraban un efecto significativo sobre el control de la enfermedad causada por E. turcicum.

Characterisation and pathological variability of Exserohilum turcicum responsible for causing northern corn leaf blight (NCLB) disease in Malaysia

Aims: Corn is grown primarily for human consumption. It is considered as the second most important cereal crop after rice in Asia. Many diseases affect this crop due to planting of susceptible hybrids. This research is aimed to characterize the causative agent of northern corn leaf blight disease in Malaysia, caused by Exserohilum turcicum. Methodology and results: Leaf samples were collected from infected farms of 2 corn growing areas of Peninsular Malaysia in 2015. A total of 5 fungal isolates were examined for cultural, morphological and molecular properties, and based on the results, the five isolates were identified as E. turcicum. The conidial shapes were observed to be elongated and spindle. Cultural characteristics showed that variation existed among the isolates in colony growth and colour. Mycelia growth rates of the isolates were significantly different on potato dextrose agar (PDA), corn meal agar (CMA) and potato sucrose agar (PSA) media, growth on CMA was faster than on PSA and PDA. The isolates were grouped into three groups based on colony colour i.e. light gray, gray and dark gray. The isolates were categorized into 2 groups based on growth namely, moderate growth and profused growth. The number of septa ranged from 5-7 to 7-10 representing isolates ET002 and ET003, respectively. Similarly, conidial length varied from 56.7 µm to 89.44 µm for isolates ET002 and ET003, respectively. The pathogenic variability tested on Thai Super Sweet (TSS) corn variety, showed that isolates ET001 and ET003 were more aggressive while isolate ET005 was less aggressive among the isolates tested. Conclusion, significance and impact of the study: Both morphology and molecular results showed that, the isolates were identified as E. turcicum. The findings of this study will serve as a baseline for future studies and will help to minimize losses in yield.

Selection of potential biological control of Exserohilum turcicum with epiphytic microorganisms from maize / Selección de microorganismos epifíticos de maíz como potenciales agentes de biocontrol de Exserohilum turcicum

The aims of this study were to select microbial isolates from phyllosphere of maize and to examine their antagonistic activity against Exserohilum turcicum. Selection was performed through the ability of isolates to compete with the pathogen using an index of dominance and to affect growth parameters of E. turcicum. Most of the epiphytic populations obtained for the screening were bacteria. These isolates were found in the order of 6 log CFU/g of leaf fresh weight. According to similar morphological characteristics and staining, 44 out of 111 isolates obtained were selected for testing antagonistic effects. At water potential, ψ, −1.38 MPa and −4.19 MPa, three Bacillus isolates showed dominance at a distance (5/0) and a significant reduction of growth rate of the pathogen. Three Bacillus isolates only decreased the growth rate of E. turcicum at −1.38 MPa. At −4.19 MPa the growth rate decreased with three isolates of Pantoea and three Bacillus. In this study a negative and significant correlation was observed between the growth rate of E. turcicum and the dominance index in the interaction of the pathogen with some bacteria. These results show that with decreasing growth rate of the pathogen the dominance index of the interaction increases. Eleven potential biocontrol agents against E. turcicum were selected.

El objetivo de este estudio fue seleccionar aislamientos microbianos de la filósfera de maíz y examinar su actividad antagonista contra Exserohilum turcicum. La selección se realizó a través de la capacidad de los aislamientos de competir con el patógeno usando un índice de dominancia y también la capacidad de afectar los parámetros de crecimiento de E. turcicum. La mayoría de las poblaciones epifíticas aisladas para la selección fueron bacterias. Estos aislamientos se encontraron en el orden de 6 log de UFC por gramo de peso fresco de hoja de maíz. En base a características morfológicas y tintóreas similares, se seleccionaron 44 de 111 aislamientos obtenidos para evaluar su capacidad antagónica. A los potenciales agua, ψ, −1,38 MPa y −4,19 MPa, tres aislados del género Bacillus mostraron dominancia a distancia (5/0) y una reducción significativa de la velocidad de crecimiento del patógeno. Tres aislamientos de Bacillus disminuyeron la velocidad de crecimiento de E. turcicum a −1,38 MPa. A −4,19 MPa la velocidad de crecimiento disminuyó con tres aislamientos de Pantoea y tres de Bacillus. En este estudio se observó una correlación negativa y significante entre la velocidad de crecimiento de E. turcicum y el índice de dominancia cuando el patógeno interactuó con algunas bacterias. Esto estaría indicando que cuando disminuye la velocidad de crecimiento del patógeno se incrementa el índice de dominancia de la interacción. Se seleccionaron once posibles agentes de biocontrol contra E. turcicum.

Avaliação de bactérias endofíticas para o controle biológico da mancha foliar de Exserohilum turcicum em milho / Assessing of endophytic bacteria for biological control of northern corn leaf blight (Exserohilum turcicum)

A eficácia de nove isolados de bactérias endofíticas foi avaliada no biocontrole da mancha foliar de Exserohilum turcicum, pela microbiolização das sementes e da parte aérea do milho híbrido AS-1548 (72 e 24 horas antes e no mesmo dia da inoculação do patógeno) em condições de casa de vegetação. Verificou-se que Bacillus subtilis 0G, Bacillus lentimorbus, Streptomyces sp. e Bacillus agaradhaerens se destacaram dos demais, quando aplicados na parte aérea, em todos os intervalos testados, com um controle na ordem de 42 a 61%. Quando as bactérias foram aplicadas nas sementes, Bacillus lentimorbus, Streptomyces sp., Ewingella americana e Xanthomonas axonopodis foram os mais eficientes, com um controle entre 37 e 59%.(AU)

The efficacy of nine endophytic bacterial strains was evaluated on biocontrol of northern corn leaf blight (Exserohilum turcicum), by microbiolization of seeds and aerial parts of maize, hybrid AS-1548 (72 and 24 hours before and at same day of the pathogen inoculation) in greenhouse conditions. It was found that Bacillus subtilis 0G, Bacillus lentimorbus, Streptomyces sp. and Bacillus agaradhaerens highlighted from the others, when applied on aerial parts of maize, in all intervals tested, presenting control in order of 42 to 61%. When the bacteria were applied on seeds, Bacillus lentimorbus, Streptomyces sp., Ewingella americana and Xanthomonas axonopodis showed more efficiency, presenting control between 37 and 59%.(AU)

Escala diagramática para avaliação de severidade da helmintosporiose comum em milho / Diagramatic scale for severity evaluation of common helminthosporium in corn

A helmintosporiose comum, causada pelo fungo Exserohilum turcicum é uma das principais doenças foliares da cultura do milho, na região sul do Brasil, e apresenta um considerável potencial de danos à cultura, especialmente quando o ataque se inicia antes do período de floração. Assim, este trabalho teve como objetivo elaborar e validar uma escala diagramática para avaliação da severidade da helmintosporiose comum do milho. Para isso, foram coletadas folhas com sintomas da doença para a determinação da severidade real, definição dos limites máximos e mínimos, e os níveis intermediários da escala por meio de incrementos logarítmicos, de acordo com a lei de estímulo visual de Weber-Fechner. A escala elaborada sugere sete níveis de severidade: 0,5; 1,0; 2,5; 6,5; 15,5; 30,0; 54,0%. A validação foi realizada por seis avaliadores, sem experiência na quantificação dessa doença, que estimaram a severidade em 30 folhas com diferentes níveis de sintomas, sem e com o auxílio da escala. A utilização da escala diagramática resultou em melhor acurácia e precisão nas estimativas realizadas, sendo uma ferramenta de fácil e rápida utilização, que pode ser adotada para auxiliar na avaliação da severidade da helmintosporiose comum do milho.

The Helminthosporium leaf blight, caused by Exserohilum turcicum, is one of the main spots that attacks corn crop in Southern Brazil. This disease causes considerable economic losses on this crop, especially when the attack begins before the flowering period. The aim of this research was to elaborate and validate a diagrammatic scale to evaluate the severity of the Helminthosporium leaf blight in corn. Corn leaves with symptoms of the disease were collected for measuring the real severity and defining the maximum and minimum limits, as well as the intermediate levels and the logarithmic increments, according to Weber-Fechner's stimulus-response law. The elaborated scale suggested seven severity levels: 0,5; 1,0; 2,5; 6,5; 15,5; 30,0 and 54,0%. The validation was performed by six persons without previous experience to quantify this disease. The severity of 30 leaves with different levels of symptoms was estimated, with and without the help of the scale. The use of the diagrammatic scale resulted in better accuracy and precision in the estimates, being a tool for quick and easy use, which can be adopted to assist in the severity evaluation of the Helminthosporium leaf blight in corn.

Keratomycosis caused by Exserohilum rostratum.

We report a case of keratomycosis caused by Exserohilum rostratum. A 46-year-old farmer presented with history of pain, watery discharge and redness of the right eye for the past 2 weeks following trauma with vegetable matter. On ocular examination, a central corneal ulcer of about 8 mm with a greyish-white slough, feathery edges and diffuse corneal edema was seen in the right eye. KOH examination of corneal scrapings revealed thick, brown, branched, septate hyphae. Culture of corneal scrapings on Sabouraud dextrose agar showed velvety greenish-black colony with a black pigment on the reverse. The culture was identified as E. rostratum on the basis of microscopic morphology. The patient responded well to treatment with topical natamycin and oral itraconazole.

Observation of Infection Process of Exserohilum monoceras and Alteration of Cellar Ultrastrncture in Barnyardgrass / 微生物学通报

The infection process of Exserohilum monoceras and alteration of cellar ultrastructure in infected barnyardgrass were observed by using scanning electron microscope and transmission electron microscope. The observation showed that the hypha began to form from the basal point of the conidia 8 hours after inoculation (HAI) and then penetrated barn-yardgrass leaves through stornata 13 HAI. The infection process finished from 24 to 26 HAI. After infected, cell membranes of the host were dramatically changed; starch particles disappeared in chloroplasts and lots of phenolic compounds occurred in the infected cells.

HT-TOXIN PRODUCED BY EXSEROHILUM TURCICUM AND SUPEROXIDATION OF MEMBRANE LIPID IN CORN CELL / 微生物学通报

Superoxidation of membrane lipid in corn leaf cells has been studied by researching the relationship between membrane permeability,the content of MDA,and the activity of POD and SOD under HT\|toxin stress.The experimental results showed that the content of MDA ascended,the POD activity was stimulated and SOD activity was inhibited in compatible combination,but POD activity was inhibited in incompatible combination.HT\|toxin strongly destroyed the permeability of cell membrane of corn,and there were positive correlation between toxin effect and toxin concentration and time exposure to toxin.It was conclusion that there may be toxin\|binding site in both resistant and susceptible cell membrane,and the difference in sensitivity of resistant and susceptible cells to toxin may result from their active oxygen metabolism.