Study of tissue inflammatory response in different mice strains infected by dematiaceous fungi Fonsecaea pedrosoi

Abstract: Background: Diseases caused by melanized fungi include mycetoma, chromoblastomycosis and phaeohyphomycosis. This broad clinical spectrum depends on the dynamic interactions between etiologic agent and host. The immune status of the host influences on the development of the disease, as, an exemple. phaeohyphomicosis is more frequently observed in immunocompromised patients. Objectives: Examine the histological inflammatory response induced by Fonsecaea pedrosoi in several different strains of mice (BALB/c, C57BL/6, Nude and SCID, and reconstituted Nude). Methods: Fonsecaea pedrosoi was cultivated on agar gel and a fragment of this gel was implanted subcutaneously in the abdominal region of female adult mice. After infection has been obtained, tissue fragment was studied histopathologically. Results: There were significant changes across the strains, with the nodular lesion more persistent in Nude and SCID mice, whereas in immunocompetent mice the lesion progressed to ulceration and healing. The histopathological analysis showed a significant acute inflammatory reaction which consisted mainly of neutrophils in the initial phase that was subsequently followed by a tuberculoid type granuloma in immunocompetent mice. Study limitations: There is no a suitable animal model for chromoblastomycosis. Conclusions: The neutrophilic infiltration had an important role in the containment of infection to prevent fungal spreading, including in immunodeficient mice. The fungal elimination was dependent on T lymphocytes. The re-exposure of C57BL/6 mice to Fonsecaea pedrosoi caused a delay in resolving the infection, and appearance of muriform cells, which may indicate that re-exposure to fungi, might lead to chronicity of infection.

Mucormycosis and chromoblastomycosis occurring in a patient with leprosy type 2 reaction under prolonged corticosteroid and thalidomide therapy / Mucormicose e cromoblastomicose em um paciente com reação hansênica tipo II sob terapia prolongada com corticosteróide e talidomida

Mucormycosis is an uncommon fungal infection caused by Mucorales. It frequently occurs in patients with neutropenia, diabetes, malignancy and on corticoid therapy. However, it is rare in patients with AIDS. Clinical disease can be manifested in several forms. The case reported illustrates the rare occurrence of chromoblastomycosis and mucormycosis in an immunosuppressed patient with multibacillary leprosy, under prolonged corticosteroid and thalidomide therapy to control leprosy type 2 reaction. Neutrophil dysfunction, thalidomide therapy and work activities are some of the risk factors in this case. Chromoblastomycosis was treated by surgical excision and mucormycosis with amphotericin B. Although the prognosis of mucormycosis is generally poor, in the reported case the patient recovered successfully. This case should alert dermatologists to possible opportunistic infections in immunosuppressed patients.

Mucormicose é uma infecção fúngica incomum causada por Mucorales. Ocorre frequentemente em pacientes com neutropenia, diabetes, corticoterapia e condições malignas. Porém, é rara em pacientes com AIDS. A doença pode apresentar-se em diferentes formas. Este caso ilustra a rara ocorrência de mucormicose e cromoblastomicose em um paciente com hanseníase multibacilar, que estava sendo tratado com prednisona e talidomida devido a eritema nodoso (reação hansênica tipo II). Disfunção de neutrófilos, uso de talidomida e atividades profissionais são alguns fatores de risco neste caso. A cromoblastomicose foi tratada por excisão cirúrgica e a mucormicose com anfotericina B. Embora o prognóstico da mucormicose seja ruim, neste caso o tratamento foi bem sucedido. Este caso alerta dermatologistas para a possibilidade de infecções oportunistas em pacientes imunossuprimidos.

The pattern of immune cell infiltration in chromoblastomycosis: involvement of macrophage inflammatory protein-1 alpha/CCL3 and fungi persistence

Chromoblastomycosis (CR) is a subcutaneous chronic mycosis characterized by a granulomatous inflammatory response. However, little is known regarding the pattern of leukocyte subsets in CR and the pathways involved in their recruitment. The objective of this study was to assess the cellular subsets, chemokine, chemokine receptors and enzymes in CR. The inflammatory infiltrate was characterized by immunohistochemistry using antibodies against macrophages (CD68), Langerhans'cells (S100), lymphocytes (CD3, CD4, CD8, CD45RO, CD20 and CD56) and neutrophils (CD15). The expression of MIP-1alpha (Macrophage inflammatory protein-1alpha), chemokine receptors (CXCR3 and CCR1) and enzymes (superoxide dismutase-SOD and nitric oxide synthase-iNOS) was also evaluated by the same method. We observed an increase in all populations evaluated when compared with the controls. Numbers of CD15+ and CD56+ were significantly lower than CD3+, CD4+, CD20+ and CD68+ cells. Statistical analysis revealed an association of fungi numbers with CD3, CD45RO and iNOS-positive cells. Furthermore, MIP-1alpha expression was associated with CD45RO, CD68, iNOS and CXCR3. Our results suggest a possible role of MIP-1alpha and fungi persistence in the cell infiltration in CR sites.

A cromomicose é micose subcutânea crônica sistêmica caracterizada por resposta inflamatória crônica granulomatosa. No entanto, existem poucos dados a respeito do padrão de subtipos de leucócitos na cromomicose e sobre as vias envolvidas no recrutamento destas células. O objetivo deste trabalho foi avaliar os tipos celulares, bem como a expressão de quimiocinas, receptores de quimiocinas e enzimas em lesões de cromomicose. O infiltrado inflamatório foi caracterizado por meio de técnica imuno-histoquímica utilizando os seguintes marcadores CD68 (macrófagos), S100 (células de Langerhans), CD3, CD4, CD8, CD45RO, CD20 e CD56 (linfócitos) e CD15 (neutrófilos). A expressão de MIP-1alfa (Proteína Inflamatória do Macrófago-1alfa), receptores de quimiocinas (CXCR3 e CCR1) e enzimas (superóxido dismutase-SOD e óxido nítrico sintase induzida-iNOS) foi avaliada pelo mesmo método. Observou-se um aumento de todas as populações celulares avaliadas em relação às amostras controle. As populações de células CD15+ e CD56+ foram significativamente menores que células CD3+, CD4+, CD20+ e CD68+. A análise estatística revelou uma correlação positiva entre o número de fungos com as células CD3, CD45RO e iNOS-positivas. A expressão de MIP-1alfa foi também associada às populações de células CD45RO, CD68, iNOS e CXCR3 positivas. Nossos resultados apontam para um possível papel de MIP-1alfa e da persistência fúngica na infiltração de células inflamatórias nos sítios de cromomicose.

Experimental murine chromomycosis mimicking chronic progressive human disease

Congenitally athymic (nu/nu) mice, mice defective in NK cell and macrophage function (bg/bg) and normal BALB/c mice were inoculated sc with 10 5-6 conidia of Fonsecae pedrosoi (FP). In immunologically intact and immunodeficient mice, a local infection developed approximately 2 weeks post-inoculation and enlarged over 1-2 weeks. In bg/bg and normal nu/+ mice, lesions resolved within 5-6 weeks. However, nu/nu mice continued to have enlarging cs lesions during >4-6 months od observation. These eventually metastasized. Lesions contained, few hyphal elements and massive numbers of sclerotic bodies. Five weeks after inoculation. 10 4-6 conidia froming units/gm of tissue were recovered from lesions. Delayed type hypersensitivity and serum antibody to FP antigens were demonstrated. Adoptive transfer of lymphocytes from nu/+ mice was followed in months bu the resolution of the lesions

Estudio de la sensibilidad cutanea a antigenos de cromoblastomicosis en Medellin y Sahagun (Colombia), 1986 / Study on cutaneous sensitivity to chromoblastomycosis antigens in Medellin and Sahagun (Colombia), 1986

Se hizo un estudio comparativo descriptivo de corte transversal, durante los meses de septiembre y octubre de 1986, en un area rural de Sahagun (Cordoba) y en el sur de la ciudad de Medellin, con el objeto de determinar mediante intradermorreaccion (IDR), la frecuencia de contacto con agentes causales de cromoblastomicosis. En Sahagun, se tomo una muestra aleatoria de 100 personas y en Medellin, se tomo una muestra de 36 trabajadores de viveros del sur de la ciudad. A ambas poblaciones se les hizo IDR con antigenos de F. pedrosoi y C. carrionii agentes causales de cromoblastomicosis en America Latina. Se aplico 0.1 ml de cada antigeno en la region anterosuperior del antebrazo. C. carrionii en el derecho y F.pedrosoi en el izquierdo. Se hicieron lecturas de las induraciones a las 24 y 48 horas, considerandose positiva toda induracion igual o mayor a 5mm de diametro; se practico examen fisico dermatologico, toma de muestras de lesiones para examen directo con KDH y serologia para titulacion de anticuerpos a quienes presentaron IDR igual o mayor a 7mm. Los datos fueron analizados por medio de las pruebas estadisticas del Chi-Cuadrado y T-Student (P=0.05). Se encontro la mayor frecuencia de positividad a la IDR para F. pedrosoi en ambas poblaciones. No se hallo diferencia en la positividad de la IDR respecto a sexo, edad y ocupacion. Ningun paciente tuvo en el momento del estudio cromoblastomicosis activa

Estudio epidemiológico de un área endémica a la cromomicosis en el estado Miranda / Epidemiological study of chromomycosis of an endemic area of the Estado Miranda

Para estudiar la sensibilidad y especificidad de los antígenos de Fonsecaea pedrosoi y Cladosporium carrionii se hace la segunda encuesta epidemiológica con estos antígenos; en esta oportunidad se escogió un área endémica a F. pedrosoi (Los Chaguaramos, estado Miranda); al mismo tiempo se prueban en 10 pacientes de cromomicosis. En el censo epidemiológico se obtiene una positividad de un 10% a F. pedrosoi y 2,5% al C. carrionii. Esto parece demostrar que el primer antígeno es más específico, pero menos sensible que el C. carrionii, al comparar estos resultados con los obtenidos en el estudio anterior