Micetoma por Nocardia asteroides / Nocardia Asteroids Mycetoma

Introducción: En 1860 Henry Van Carter introdujo la definición del micetoma y desde 1884 se reportan los primeros casos en África (Sudán, Senegal). Estas infecciones afectan la piel, el tejido celular subcutáneo y, en ocasiones, los músculos, los huesos, y pueden diseminarse por la cavidad torácica, la abdominal, y por otras regiones del cuerpo. Objetivo: Presentar un caso de micetoma por Nocardia asteroides con evolución desfavorable y tratamiento. Presentación del caso: Paciente masculino de 47 años de edad que sufrió hace 18 años un trauma en la rodilla izquierda con herida avulsiva y evolución desfavorable por infección. Diez años después presentó en el mismo sitio múltiples lesiones fistulosas con drenaje activo, secreción serohemática escasa y no fétida. En varias ocasiones fue llevado al salón de operaciones para realizarle debridamientos quirúrgicos y toillete y recibió múltiples tratamientos antibióticos y antifúngicos. Se concluyó el caso como un micetoma y se aisló una Nocardia asteroides. El paciente estuvo en desacuerdo con la amputación de la extremidad como tratamiento quirúrgico definitivo. Llegó a nuestro centro en octubre del 2020 con mal estado general y extensión severa del proceso infeccioso en toda la extremidad. Se planificó una hemipelvectomía como tratamiento definitivo, pero desafortunadamente el paciente falleció antes, debido a complicaciones generales. Conclusiones: Ante la aparición del micetoma es importante definir el alcance de la infección para determinar el tipo de tratamiento a utilizar, ya que bien empleado y de forma oportuna, puede salvar la vida al paciente sin dejar graves secuelas(AU)

Introduction: In 1860, Henry Van Carter introduced the definition of mycetoma and since 1884 the first cases have been reported in Africa (Sudan, Senegal). These infections affect the skin, the subcutaneous cellular tissue and, sometimes, the muscles, the bones, and it can spread throughout the thoracic cavity, the abdominal cavity, and other regions of the body. Objective: To report a case of mycetoma due to nocardia asteroides with unfavorable evolution and treatment. Case report: We report the case of a 47-year-old male patient who suffered a left knee trauma 18 years ago with an avulsive wound and unfavorable evolution due to infection. Ten years later, he presented, in the same site, multiple fistulous lesions with active drainage, scant serohematic, non-fetid secretion. On several occasions he was taken to the operating room for surgical debridement and toilette and he received multiple antibiotic and antifungal treatments. The case was concluded as a mycetoma. Nocardia asteroides was isolated. The patient disagreed with limb amputation as definitive surgical treatment. He came to our treatment center in October 2020 with poor general condition and severe extension of the infectious process throughout the limb. A hemipelvectomy was planned as definitive treatment, but unfortunately the patient deceased before due to general complications. Conclusions: Before the appearance of mycetoma, it is important to define the extent of the infection to determine the type of treatment to use, since it can save the patient's life if properly used and in a timely manner without leaving serious sequelae(AU)

Climate, soil type, and geographic distribution of actinomycetoma cases in Northeast Mexico: A cross-sectional study.

BACKGROUND: Mycetoma is a chronic, granulomatous infection of subcutaneous tissue, that may involve deep structures and bone. It can be caused by bacteria (actinomycetoma) or fungi (eumycetoma). There is an epidemiological association between mycetoma and the environment, including rainfall, temperature and humidity but there are still many knowledge gaps in the identification of the natural habitat of actinomycetes, their primary reservoir, and their precise geographical distribution. Knowing the potential distribution of this infection and its ecological niche in endemic areas is relevant to determine disease management strategies and etiological agent habitat or reservoirs. METHODOLOGY/PRINCIPAL FINDINGS: This was an ambispective descriptive study of 31 patients with actinomycetoma. We determined the biophysical characteristics including temperature, precipitation, soil type, vegetation, etiological agents, and mapped actinomycetoma cases in Northeast Mexico. We identified two disease cluster areas. One in Nuevo Leon, with a predominantly kastanozems soil type, with a mean annual temperature of 22°, and a mean annual precipitation of 585.2 mm. Herein, mycetoma cases were produced by Actinomadura pelletieri, Actinomadura madurae, Nocardia brasiliensis, and Nocardia spp. The second cluster was in San Luis Potosí, where lithosols soil type predominates, with a mean annual temperature of 23.5° and a mean annual precipitation of 635.4 mm. In this area, all the cases were caused by N. brasiliensis. A. madurae cases were identified in rendzinas, kastanozems, vertisols, and lithosols soils, and A. pelletieri cases in xerosols, kastanozems, and rendzinas soils. Previous thorn trauma with Acacia or Prosopis plants was referred by 35.4% of subjects. In these states, the presence of thorny plants, such as Acacia spp., Prosopis spp., Senegalia greggi, Vachellia farnesiana and Vachellia rigidula, are common. CONCLUSIONS/SIGNIFICANCE: Mapping this neglected tropical infection aids in the detection of disease cluster areas, the development of public health strategies for early diagnosis and disease prediction models; this paves the way for more ecological niche etiological agent research.

Keratinocyte infection by Actinomadura madurae triggers an inflammatory response.

BACKGROUND: Actinomycetoma is a syndrome of the skin characterized by chronic inflammation and lesions with nodular grain-like structures. The most common aetiological agents are Nocardia brasiliensis and Actinomadura madurae. In response to infection with these organisms the body produces an inflammatory immune response in the skin. The aim of the present study was to determine the production of chemokines, pro-inflammatory cytokines, antimicrobial peptides and the expression of Toll-like receptors (TLRs) in keratinocytes infected by A. madurae. METHODS: A cell line of HaCaT keratinocytes was infected with A. madurae at a multiplicity of infection of 20:1 for 2 h and the samples were collected from 2 to 72 h post-infection. Intracellular replication of the bacterium was evaluated by counting of colony-forming units, the TLR expression and antimicrobial peptide production were assayed by confocal microscopy and chemokine and pro-inflammatory cytokine levels were determined by enzyme-linked immunosorbent assay. RESULTS: Early in the infection, A. madurae was able to achieve intracellular replication in keratinocytes, however, the cells eventually controlled the infection. In response to the infection, keratinocytes overexpressed TLR2 and TLR6, produced high concentrations of cytokines monocyte chemoattractant protein-1, interleukin 8, human ß-defensin-1, human ß-defensin-2 and LL37 and low levels of tumour necrosis factor α. CONCLUSIONS: The human keratinocytes contribute to the inflammatory process in response to A. madurae infection by overexpressing TLRs and producing chemokines, pro-inflammatory cytokines and antimicrobial peptides.

Mycetomas: an epidemiological, etiological, clinical, laboratory and therapeutic review.

Mycetoma is a chronic suppurative disease of the skin and subcutaneous tissue, characterized by a symptomatic triad: tumor, fistulas and grains. It can be caused by fungi (eumycetoma) and bacteria (actinomycetoma), with similar clinical features. Diagnosis is based on the clinical presentation and identification of the etiological agents in the tissue, by mycological/bacteriological, histopathological and immunohistochemical tests. It is important to specify the fungal or bacterial etiology, because the treatments are different. An approach that involves early diagnosis, the use of systemic antibiotics or antifungal agents, including surgical removal of lesions, is the basis for the treatment of these diseases. In this review, the most commonly used diagnostic methods and treatments will be discussed. Also, we will review the history of the disease through epidemiological and etiological aspects.

Mycetomas: an epidemiological, etiological, clinical, laboratory and therapeutic review

Abstract: Mycetoma is a chronic suppurative disease of the skin and subcutaneous tissue, characterized by a symptomatic triad: tumor, fistulas and grains. It can be caused by fungi (eumycetoma) and bacteria (actinomycetoma), with similar clinical features. Diagnosis is based on the clinical presentation and identification of the etiological agents in the tissue, by mycological/bacteriological, histopathological and immunohistochemical tests. It is important to specify the fungal or bacterial etiology, because the treatments are different. An approach that involves early diagnosis, the use of systemic antibiotics or antifungal agents, including surgical removal of lesions, is the basis for the treatment of these diseases. In this review, the most commonly used diagnostic methods and treatments will be discussed. Also, we will review the history of the disease through epidemiological and etiological aspects.

Pie de madura: primer caso en nuestro país y breve actualización (1904-2013) / Foot of madura: first case in our country and brief update (1904-2013)

Presentamos el primer caso de pie de madura publicado en Argentina y realizamos una breve actualización de su diagnóstico y terapéutica.

We presented the first case of feet of Madura published in Argentine. We did a review of diagnostic and treatment.

Eumycetoma.

Eumycetoma is caused by different fungi. Madurella mycetomatis, Madurella grisae, and Scedosporium apiospermum are the most common causative agents. This disease is more frequent on the lower extremities but can also be present in other areas. The diagnosis is made by direct microscopic examination and histologic study, which should show hyphae and vesicles characteristic of the fungi. Etiologic identification of the species of the fungus is sometimes difficult by culture and biopsy specimen; in these cases, molecular techniques can help to identify the infecting organism. Treatment has been with amphotericin B, which is now seldom used due to its side effects and limited success. The best therapeutic choice is surgical removal of the lesion, followed by medical treatment. This includes antifungals such as the azoles, ketoconazole and itraconazole; in resistant cases, posaconazole and voriconazole are currently recommended. In particular, the combination of terbinafine and itraconazole can elicit a good result in some cases.

Host defenses in subcutaneous mycoses.

Subcutaneous mycoses include diverse clinical syndromes, characterized by invasion of the skin and subcutaneous tissue by saprobic fungi. Individuals living in rural areas constantly suffer lesions or trauma; however, only a few of them develop disease. In this contribution, we describe recent advances in the understanding of the virulence of these organisms, focusing on the most prevalent infections, sporotrichosis, chromoblastomycosis, and mycetoma. Although these infectious diseases are considered neglected tropical diseases, modern molecular techniques have been able to identify the etiologic agents and observe variations in the former monolithic concept of the species, which was based mostly on morphologic characteristics. The complete genetic characterization of the causative agents, along with that of their host, will help in the understanding of the factors on which the development of these infections depends.

Difficult mycoses of the skin: advances in the epidemiology and management of eumycetoma, phaeohyphomycosis and chromoblastomycosis.

PURPOSE OF REVIEW: Eumycetoma, phaeohyphomycosis and chromoblastomycosis are subcutaneous mycoses having in common the fact that they are acquired as a result of penetrating trauma to the skin and may be caused by a large variety of fungi. This article will review recent data regarding the epidemiology and treatment of these infections. RECENT FINDINGS: Recent epidemiologic observations in these mycoses include an increased incidence of phaeohyphomycosis in immunosuppressed patients, the association of polymorphisms in genes involved in innate immunity, the occurrence of eumycetoma caused by Madurella mycetomatis and the nosocomial acquisition of phaeohyphomycosis. The management of these infections continues to be challenging. An approach that involves early diagnosis, the use of systemic antifungal agents and local therapies, including surgical removal of lesions, is the basis of the treatment of these diseases. SUMMARY: It is crucial that the epidemiology and clinical presentation of these infections are understood if we are to improve their outcomes.

Micetoma: reporte de un caso / Mycetoma: a case report

Se presenta el caso un paciente de 62 años de raza negra que sufrió una lesión en el pie derecho hace 20 años, luego desarrolló una lesión supurativa-ulcerosa que de forma intermitente necesitó tratamiento antimicrobiano. En las fotos del paciente y las imágenes radiológicas se visualizaron datos de reabsorción ósea y esclerosis de los huesos del pie derecho, todo esto es compatible con la presencia de un micetoma(AU)

A case of a black race of 62 years-old patient that suffered a lesion in the right foot 20 years ago is presented, developed a suppurative-ulcerous lesion that needed antimicrobial treatment of intermittent form. In the photos and in the radiological images of the patient sclerosis and osseous resorption data of the bones of the right foot were visualized, all this is compatible with the presence of a mycetoma(AU)

Endobronchitis by Scedosporium apiospermum in a child with cystic fibrosis.

A case of endobronchitis by Scedosporium apiospermum in a child with cystic fibrosis is presented. The bronchial aspirate's cytology showed the presence of a large amount of septated-dichotomized hyphae. The bronchial aspirate's culture showed the presence of Scedosporium apiospermum in a pure culture of three consecutive samples. The scanning electron microscopy study of the mucosal surface revealed scarce mycelia with the presence of abundant conidiae. The transmission electron microscopy of the mucosa revealed inflammatory infiltrates constituted by macrophages, polymorphonuclear leukocytes, a lot of dichotomized mycelia and macrophages with hyphae and conidiae within the phagosomes. The patient was treated with amphotericin B and itraconazole.

Emerging moulds: Fusarium, Scedosporium and Zygomycetes in transplant recipients.

PURPOSE OF REVIEW: The incidence of non-Aspergillus mould infections in transplant recipients has increased over the past decade. This paper will review recent data regarding the epidemiology, clinical manifestations, treatment and the outcome of infections caused by Fusarium spp., Scedosporium spp. and the Zygomycetes in transplant recipients. RECENT FINDINGS: Although the reasons for the increased incidence of non-Aspergillus mould infections in transplant recipients are not very clear, changes in transplant procedures, resulting in more severe immunosuppression, seem to play a major role, as suggested by recent epidemiologic data. Infections caused by these fungi have a tendency to be disseminated, and the prognosis is usually poor because the fungi are resistant to most of the available antifungal agents. New drugs, particularly the new azoles, may have a role in the treatment and prophylaxis of these infections, but the available data are still scant. SUMMARY: The understanding of the changing epidemiology of fungal infections and their implications for the prognosis of transplant recipients are important to better evaluate the impact of new transplant procedures.

Atypical skin lesions caused by Curvularia sp. and Pseudallescheria boydii in two patients after allogeneic bone marrow transplantation.

We report two patients who developed atypical skin lesions caused by Curvularia sp. and Pseudallescheria boydii after allogeneic bone marrow transplantation for severe aplastic anemia. The first patient (female, 18-year-old) had multiple hemorrhagic vesicles on day +30 after her second BMT for graft failure. Pseudallescheria boydii was isolated from a skin biopsy. The patient died of respiratory failure probably as a consequence of systemic fungal infection. The second patient (male, 9-year-old) developed an ecthyma gangrenosum-like lesion on his right palm on day +8. Curvularia sp. was isolated from a skin biopsy. Liposomal amphotericin was given to achieve a total dose of 30 mg/kg and followed by oral itraconazole until steroids were discontinued. The infection resolved completely and the patient has remained disease-free. We conclude that emerging fungal organisms such as those described in this report are increasingly recognized in this setting. Early recognition and biopsy of these cutaneous lesions will allow prompt initiation of therapy to prevent systemic infection.

Actinomicetoma / Actinomycetoma

El actinomiocetoma es una enfermedad crónica de la piel y tejidos subcutáneos de evolución muy lenta y por tanto poco invalidante durante los primeros meses o años de su aparición. Esto ocasiona que su diagnóstico y tratamiento resulten una desventaja para el individuo que la padece y favorece al progreso de la enfermedad. Un problema adicional es que la incidencia de esta patología en nuestro país es baja y se presenta preferentemente en poblaciones que trabajan en el campo; por esta razón, el presente trabajo de revisión bibliográfica tiene como principal objetivo actualizar la información acerca de las principales características de este padecimiento, las estrategias de diagnóstico y tratamiento, así como las evidencias experimentales que permiten su estudio en un modelo animal

Actinomicetoma / Actinomycetoma

El actinomiocetoma es una enfermedad crónica de la piel y tejidos subcutáneos de evolución muy lenta y por tanto poco invalidante durante los primeros meses o años de su aparición. Esto ocasiona que su diagnóstico y tratamiento resulten una desventaja para el individuo que la padece y favorece al progreso de la enfermedad. Un problema adicional es que la incidencia de esta patología en nuestro país es baja y se presenta preferentemente en poblaciones que trabajan en el campo; por esta razón, el presente trabajo de revisión bibliográfica tiene como principal objetivo actualizar la información acerca de las principales características de este padecimiento, las estrategias de diagnóstico y tratamiento, así como las evidencias experimentales que permiten su estudio en un modelo animal (AU)

Immune response to Nocardia brasiliensis antigens in an experimental model of actinomycetoma in BALB/c mice.

Nine- to twelve-week-old BALB/c mice were injected in footpads with 10(7) CFU of a Nocardia brasiliensis cell suspension. Typical actinomycetoma lesions, characterized by severe local inflammation with abscess and fistula formation, were fully established by day 28 after infection. These changes presented for 90 days, and then tissue repair with scar formation slowly appeared, with complete healing after 150 days of infection. Some animals developed bone destruction in the affected area. Histopathology showed an intense inflammatory response, with polymorphonuclear cells and hyaloid material around the colonies of the bacteria, some of which were discharged from draining abscesses. Sera from experimental animals were analyzed by Western blotting, and immunodominant antigens P61 and P24 were found as major targets for antibody response. Anti-P24 immunoglobulin M (IgM) isotype antibodies were present as early as 7 days, IgG peaking 45 days after infection. Lymphocyte proliferation with spleen and popliteal lymph node cells demonstrated thymidine incorporation at 7 days after infection, the stimulation index decreasing by day 60. Levels of interleukin-1 (IL-1), IL-2, IL-4, IL-6, tumor necrosis factor alpha, and gamma interferon (IFN-gamma) were determined by enzyme-linked immunosorbent assay in the sera of infected animals. The circulating levels of IFN-gamma increased more than 10 times the basal levels; levels of IL-4, IL-6 and IL-10 also increased during the first 4 days of infection.

Diecisiete casos de micetomas actino y eumicóticos en Rosario, Argentina (1959-1998) / Seventeen cases of actno and eumycotic mycetoma in Rosario, Argentina (1959-1998)

Se comunican diecisiete casos de micetomas estudiados en el período comprendido entre enero de 1958 y noviembre de 1998, 10 eumicóticos (59 porciento) y 7 actinomicóticos (41 porciento) madurella grisea fue el agente más aislado (29.5 porciento) en los primeros y nocardia asteroides (17.6 porciento) en los segundos. Los agentes restantes fueron pseudallescheria boidii, madurella mycetomatis, fusarium solani, mocardia brasiliensis y actinomadura madurae. A pesar que los micetomas son afecciones benignas, las dificultades terapéuticas los transforman en cuadros clínicos más serios