Transmission study of Andes hantavirus infection in wild sigmodontine rodents.

Our study was designed to contribute to an understanding of the timing and conditions under which transmission of Andes hantavirus in Oligoryzomys longicaudatus reservoir populations takes place. Mice were caged in test habitats consisting of steel drums containing holding cages, where seronegative rodents were exposed to wild seropositive individuals by freely sharing the same cage or being separated by a wire mesh. Tests were also performed for potential viral transmission to mice from excrement-tainted bedding in the cages. Andes virus transmitted efficiently; from 130 attempts with direct contact, 12.3% resulted in virus transmission. However, if we consider only those rodents that proved to be infectious, from 93 attempts we obtained 16 infected animals (17.2%). Twelve of them resulted from intraspecies O. longicaudatus encounters where male mice were differentially affected and 4 resulted from O. longicaudatus to Abrothrix olivaceus. Experiments using Abrothrix longipilis as receptors were not successful. Transmission was not observed between wire mesh-separated animals, and mice were not infected from excrement-tainted bedding. Bites seemed not to be a requisite for oral transmission. Genomic viral RNA was amplified in two out of three saliva samples from seropositive rodents, but it was not detected in urine samples obtained by vesicle puncture from two other infected rodents. Immunohistochemistry, using antibodies against Andes (AND) hantavirus proteins, revealed strong reactions in the lung and salivary glands, supporting the possibility of oral transmission. Our study suggests that AND hantavirus may be principally transmitted via saliva or saliva aerosols rather than via feces and urine.

Dermatomycoses caused by Nattrassia mangiferae in São Paulo, Brazil.

Nattrassia mangiferae formerly known as Hendersonula toruloidea, is a phaeoid coelomycete described by Nattrass in 1933. We report five cases of N. mangiferae infections in São Paulo, Brazil. This fungus was isolated from interdigital lesions on the feet in one patient, toenails in three cases and fingernails in the other one. The infections were initially considered to be caused by a dermatophyte. Although there are only a few cases described in the medical literature, the five cases reported suggest that N. mangiferae should be taken into consideration in the differential diagnosis of tinea pedis infections.

Onychomycosis caused by Fusarium solani and Fusarium oxysporum in São Paulo, Brazil.

Fusarium species are common soil saprophytes and plant pathogens that have been frequently reported as etiologic agents of opportunistic infections in humans. We report eight cases of onychomycosis caused by Fusarium solani (4) and Fusarium oxysporum (4) in São Paulo, Brazil. These species were isolated from toenails in all cases. The infections were initially considered to be caused by dermatophytes. The clinical appearance of the affected toenails was leukonychia or distal subungual hyperkeratosis with yellowish brown coloration. The eight cases reported here suggest that Fusarium spp. should be taken into consideration in the differential diagnosis of tinea unguium.

Phaeoisaria clematidis as a cause of keratomycosis.

We report the first case of human infection by Phaeoisaria clematidis. This fungus caused a corneal ulcer in a Brazilian man who had previously suffered an eye injury. Diagnosis was established by positive direct examination and repeated cultures. The isolate was clearly resistant in vitro to the six antifungal agents tested.

Subcutaneous hyalohyphomycosis caused by Colletotrichum gloeosporioides.

The coelomycete Colletotrichum gloeosporioides was isolated in pure culture from subcutaneous nodules of the left forearm and elbow of a farmer after traumatic injury. To our knowledge, we report the first case involving this fungus as an etiological agent of subcutaneous infection. The in vitro inhibitory activities of amphotericin B, itraconazole, ketoconazole, miconazole, flucytosine, and fluconazole were studied.

Candida albicans morphotypes from oral cavity in several families

Se estudiaron 108 personas provenientes de 22 familias compuestas de 3 a 8 miembros cada una, para la búsqueda de morfotipos de candida albicans de la cavidad bucal con o sin piezas dentarias. Por la técnica de phongpaichit et. al., morfotipos idénticos o diferentes fueron detectados en 7 grupos familiares. En 10 familias, c. albicans fue aislada de la familia y de protesis dentarias removibles de un mismo individuo. La franja discontinua, considerada como probable indicador de virulencia fue detectada en 9 (16,7 porciento) de las cepas de c. albicans de personas con dentición completa y de saliva de usuarios y no usuarios de prótesis. La franja continua fue verificada en 5 (83,3 porciento) de las cepas de c. albicans aisladas de un mismo sitio. El morfotipo es simple, fácil de ejecutar, puede servir para detectar infección cruzada y como un posible indicador de riesgo de candidosis. C. albicans fue la especie prevalente (86,4 porciento), detectándose a lo menos en 2 miembros de 14 familias

Viabilidad de dermatofitos en muestras clínicas almacenadas / Viability of dermatophytes in stored clinical samples

Con la finalidad de determinar la viabilidad en el tiempo de las estructuras fúngicas de dermatofitos y levaduras en muestras clínicas almacenas, se estudiaron 257 muestras ( 2 a 7 años de antiguedad) colectadas entre enero de 1990 y diciembre de 1994 (206 de uña, 43 de piel y 8 de pelo). El exámen microscópico directo se realizó con KOH-tinta parker y posterior cultivo en agar sabouraud-CAF y agar lactrimiel-VAF por 10-15 días a 28ºC. Como controles se analizaron con la misma metodología, 33 muestras de 5-8 meses de almacenamiento. En el 100 porciento de las muestras control, se observaron elementos fúngicos y solo en el 21,2 porciento de las almacenadas durante 5-6 meses se logró aislar nuevamente el agente causal. La especie más detectada fue t. rubrum. El 70,4 porciento de las muestras almacenadas por un periodo superior a los 8 meses presentaron estructuras fúngicas al exámen microscópico, sin embargo, todos sus cultivos resultaron negativos

[Mycetomas caused by Microsporum canis. Report of one case]. / Micetomas por Microsporum canis. Caso clínico.

We report an eight years old boy presenting with a pyogenic granuloma of the scalp, generalized alopecia, descamative plates in the neck, trunk and limbs and nail involvement. Cultures for fungus of all these lesions disclosed Microspore canis. The patient was treated with oral griseofulvin, miconazole and topical tolnaftate. Five years later and after several incomplete treatments, the patient returns with a fistulous mass of 15 x 8 cm in the dorsal area whose culture revealed Microspore canis. The mass was excised and oral ketoconazole was indicated. After three months of follow up, the patient was lost from control.

Ultrastructural aspects of hair digestion in black piedra infection.

The ultrastructural pattern of human hair infection by Piedraia hortae in vivo has been studied. The fungus destroyed the cuticular layers of the hair and was able to penetrate deeply into the cortex. The course of destruction of human hair is described and compared with that produced by other fungi. Two well-defined types of cortex digestion were characterized. The slow rate of keratin degradation at the cortex together with the compacted stromatic organization of the nodules are argued as the main reasons that guarantee the long survival of the fungus, and therefore the chronic course of the disease. The data provided in this paper may help to understand the mechanisms that regulate the pathogenicity of this fungus.

Isolation of Malassezia furfur from patients with onychomycosis.

Malassezia furfur (Pityrosporum ovale IP. orbiculare) was found microscopically and by culture in the nails in 14 of 370 patients seen for treatment of onychomycosis in São Paulo, Brazil. The clinical features, predisposing factors and laboratory diagnosis are discussed.

[Antibiotic effect of wild Streptomyces strains isolated from Chilean soils]. / Efecto antibiótico de cepas silvestres de Streptomyces aisladas de suelos chilenos.

BACKGROUND: The soils of the southern part of Chile, that are isolated, cold, humid, poorly oxygenated and with a low acidity, could contain new strains of antimicrobial producing Streptomyces. AIM: To demonstrate that the soil of the Southern region of Chile contains Streptomyces strains with antimicrobial activity towards pathogenic bacteria and fungi. MATERIAL AND METHODS: Two hundred fifty eight soil and sediment samples were collected from 148 places in Southern regions of Chile. They were cultured in Küster-Williams growth media and the presence of Streptomyces was confirmed by microscopic examination and biochemical characterization. The antimicrobial activity against reference microorganisms of each wild strain was tested using the disk method. Among active Streptomyces strains, 38 with the higher activity were selected and tested against 142 clinical microorganisms. RESULTS: Seventy seven percent of soils were positive and 542 wild strains of Streptomyces were isolated; of these, 266 had antimicrobial activity. Fifty three percent of isolates had activity against S aureus 43% against B subtilis and 0.7% against E coli. Most Streptomyces were active against more than one organism. When there was activity against single organisms, these were mostly eucariotic, such as C albicans and T mentagrophytes. Among clinical microorganisms, 29% of S aureus strains were inhibited, while P aeruginosa, Alternaria sp, P vulgaris and Y enterocolitica strains were not inhibited. The most frequent Streptomyces morphotypes were those showing pigmented colonies with flexuous and spiral shaped chains of arthrospores. CONCLUSIONS: Soils of the Southern region of Chile allow the growth of abundant native strains of Streptomyces with a promising antimicrobial activity.

[White piedra. Report of a case]. / Piedra blanca. Informe de un caso.

The most common superficial mycosis caused by Trichosporon beigelii is white piedra. We report a 18 years old male that had in several hairs of the scalp, white-yellowish nodules of 1 mm diameter, agglutinated or forming chains, even forming threads, with a greasy aspect. Trichosporon beigelii was identified in cultures. Oral and topical antimycotics were prescribed and the patient was lost from follow up.

Actividad de antisépticos en malassezia pachydermatis aislada de oído externo en perros y gatos / Antiseptics activity on malassezia pachydermatis isolated from external ear in dogs and cats

Se estudiaron en agar sabouraud dextrosado, muestras obtenidas del conducto auditivo externo de 80 perros y 22 gatos aparentemente sanos. El examen micológico directo y las características morfofisiológicas y bioquímicas, permitieron determinar la presencia de malassezia pachydermatis en el 61,3 porciento de las muestras provenientes de perros y en el 13,6 porciento de los gatos. La susceptibilidad de esta levadura se determinó en medios sólidos, por el método de dilución in vitro frente a soluciones de yodo, timerosal y violeta de genciana. Todas las cepas fueron inhibidas en las siguientes concentraciones: yodo 1,0 g/l; timerosal 0,0125 g/l y violeta de genciana a 0,0078 g/l, lo que representa su dilución comercial diluída 641 veces

Agentes de onicomicosis en manos y pies en Valdivia (Chile) / Onichomycosis agents in hands and feet in Valdivia (Chile)

Se estudiaron 78 muestras de uñas de manos y pies de 74 pacientes con diagnóstico de onimicosis. Para la obtención de la muestra se raspó la lámina interna de la uña, excepcionalmente la lámina externa y se efectuó el examen microscópico directo ya sea en koh-20 porciento-tinta parker 51 azul permanente o con koh-20 porciento-chloroback e. Todas las muestras fueron sembradas en agar sabouraud dextrosado, agar lactrimel y agar selectivo para dermatofitos (dim) e incubadas a 28ºC por 10-15 días. De las muestras estudiadas, en el 79,5 porciento se observaron hongos al examen microscópico directo, aislándose estos en el 61,5 porciento de los cultivos. La frecuencia de agentes de onimicosis fue: c. albicans (43,75 porciento), t. rubrum (31,25 prociento) y t. mentagrophytes (10,42 porciento). C.albicans se aisló en el 70,8 porciento de las onimicosis en manos de mujeres. T.rubrum se aisló en un 50 y 25 porciento de hombres y mujeres respectivamente. En pie se aisló en el 52,9 porciento y en mano en un 19,3 porciento. S. brevicaulis fue aislado en un solo caso

[The differentiation of Candida albicans strains by the killer system]. / Diferenciação de cepas de Candida albicans pelo sistema killer.

The authors studied the killer effect of nine standard strains of yeasts on 146 samples of Candida albicans isolated from the following clinical specimens: oral mucosa, feces, bronchial wash, sputum, vaginal secretion, urine, skin lesion, nail lesion and blood. Using this system it was possible to differentiate 23 biotypes of Candida albicans. The biotypes 211, 111 and 811 were most frequently isolated. Most of the samples of C. albicans (98.6%) were sensitive to at least one or more of the nine killer strains. Using the killer system it was possible to show that two patients harbored the same killer biotypes, 111 and 211, respectively, in different clinical specimens and another patient harbored the same biotype (211) in bloodcultures effected in different ocasions. The utilization of the killer system to differentiate types among species of pathogenic yeasts can be a useful method to establish the eventual source of infection, and it is a valuable tool to control and watch for nosocomial infections caused by yeasts.

[Kerion Celsi. A diagnostic problem? Experience with 6 cases]. / Querion de Celso. Un problem diagnóstico? Experiencia en 6 pacientes.

We report six patients with Kerion Celsi due to Trichophyton verrucosum. Five of the patients were hospitalized with the diagnosis of Staphylococcal abscess. This confusion is due to that highly suppurative and inflammatory nature of the infection. Griseofulvin is the antimicrobial of choice for treatment, associated with imidazolics and corticosteroids to prevent alopecia. The authors suggest that an adequate use of simple microbiological diagnostic tests in the diagnosis of pyodermitis in rural children, may prevent unnecessary hospitalizations and permanent hair loss.

Nattrassia Mangiferae, H. toruloidea: an agent of cutaneous phaeohyphomycosis in Brazil

Se describen dos casos de micosis de uñas y piel producidas por Nattrassia mangiferae en dos pacientes que nunca salieron de Brasil. El uso de medios de cicloheximida, la cual inhibe el desarrollo de este hongo, puede explicar porque él es infrecuentemente diagnosticado

Agarose gel immunodiffusion tests with the addition of PEG (polyethylene glycol 6000) for the diagnosis and serological follow up of paracoccidioidomycosis infection.

By using PEG (polyethylen glycol 6000) in the gel immunodiffusion tests (ID), the precipitin lines were increased in 25.5% of the 192 sera reactions and the titers were increased from one to four serial dilutions in 44.6% of the 139 serum samples. Owing to its sensitivity, easy interpretation of the results and low cost, the use of 2% PEG incorporated into the gel in ID tests is recommended for the diagnosis and serological follow-up of paracoccidioidomycosis infections.