[Diagnosis, clinical aspects and therapy of early chromoblastomycosis in a case example]. / Diagnostik, Klinik und Therapie der frühen Chromoblastomykose an einem Fallbeispiel.

Despite the availability of modern antimycotics, which produce high cure rates in early infections, the therapy of advanced chromoblastomycosis is still unsatisfactory. An initial chromoblastomycosis caused by a hitherto unidentified species of the genus Phialophora was diagnosed in a 46-year-old teacher. The organism was isolated twice at an interval of 6 weeks from a partly psoriasiform, partly verrucous lesion on the 4th toe. The infection was apparently acquired 4 years ago during a holiday at Cape Verde. Treatment with itraconazole (Sempera). 200 mg/day, and amphotericin B (Ampho-Moronal) cream for 6 weeks initially resulted in rapid regression. However, 4 weeks after cessation of therapy, the Phialophora species was cultured again from skin scrapings. Complete healing was achieved after re-treatment with itraconazole for 20 weeks at the same dosage in combination with topical amorolfine and local hyperthermia. Until now, no relapse has occurred. The present case demonstrates that this rare disease, which mainly occurs as a traumatic mycosis in the rural population of tropical regions, must be included in the differential diagnosis of psoriasiform or verrucous skin lesions and also included in the list of diseases which may be acquired while on vacation in exotic locations.

Phialophora repens, an emerging agent of subcutaneous phaeohyphomycosis in humans.

A 63-year-old Japanese man had phaeohyphomycosis that occurred as a solitary subcutaneous nodule on the dorsal aspect of his left hand. In the nodule there were foci of mixed granulomatous and suppurative infiltrations circumscribed by thick fibrous tissue reaction. The foci contained short septate hyphae and occasionally small rounded aggregates of irregularly branched septate hyphae, both of which were nonpigmented or rarely weakly pale brown. Fungal culture from the nodule was positive for a dematiaceous mold. The mycologic features of the mold were typical of Phialophora repens. The infection was successfully treated by excision of the nodule. This is the second reported case of infection due to P. repens.

The mucilage secreted by roots and its possible role in cell-cell recognition for the adhesion of fungal pathogens to root surfaces of Zea mays L.

The outer cells of the roots of plants secrete a mucilage which lubricates the root and keeps it moist. The mucilage is secreted from the Golgi apparatus in vesicles which fuse at the plasma membrane. In maize roots a complex of at least three polysaccharides and glycoproteins are formed, some of which have a large proportion of fucose in their composition. The synthesis of these compounds can be readily monitored because fucose can be easily identified, and especially because exogenous fucose is not catabolized but is incorporated intact into the polymers. The synthesis of the polymers seems to be initiated in the endoplasmic reticulum in conjunction with polyprenoid oligosaccharides that contain fucose. Lipid-oligosaccharides of nine sugar residues can be obtained from the membrane preparations of the root cells. These compounds are polyprenyl diphosphate derivatives. A GDP-fucose:polyprenyl phosphate transfucosylase occurs in the endoplasmic reticulum, whereas fucosyl transferase that transfers fucose to a polymer occurs mainly in the Golgi apparatus. The indirect evidence suggests that oligosaccharides of polyprenyl diphosphate compounds are transferred to proteins, elaborated in the Golgi apparatus, and large molecular weight polysaccharides are finally exported as the mucus. Part of the mucus is acidic and in some respects resembles pectin. The presence of fucose in such large quantities in maize root mucilage suggested that this might have some significance for the recognition of these plants by parasitic root fungi. The adsorption of mucilage by pathogenic fungi was investigated with two types of fungi, a highly specialized ectotrophic root-infecting fungus, e.g. Phialophora radicicola and a vascular wilt fungus capable of attacking a great variety of tissues, e.g. Fusarium moniliforme. The adsorption of radioactively labelled and fluorescently labelled polymers by the pathogenic fungi was investigated. The character and proportion of fungal surfaces present in vitro were standardised by the production and semi-synchronous germination of populations of conidia. Changes in appearance of fungal walls, present before and after germination, were examined ultrastructurally. There was polyanionic material on hyphal but less on conidial surfaces of the ectotrophic root-infecting fungi. In contrast this material was present to similar extents on both hyphal and conidial surfaces of F. moniliforme.(ABSTRACT TRUNCATED AT 400 WORDS)

Role of the fungal cell wall in the granulomatous response of mice to the agents of chromomycosis.

Mice were given, intraperitoneally, inocula of a cell-wall preparation and fractions thereof from Fonsecaea pedrosoi, F. compactum, Cladosporium carrioni and Phialophora verrucosum. Large doses of cell-wall preparation, with or without trypsin treatment, produced a pronounced loss of body weight, a granulomatous reaction and, sometimes, death. After extraction of the cell wall preparation with 1N NaOH, three fractions were obtained: an alkali-insoluble fraction 1; an alkali-soluble acid-insoluble fraction 2; and an alkali- and acid-soluble fraction 3. Intravenous administration showed that only fraction 1 induced a granulomatous reaction and death in mice.

Phialophora richardsiae isolated from infected human bone: morphological, physiological and antifungal susceptibility studies.

A dematiaceous fungus, Phialophora richardsiae (Nannf.) Conant, was isolated from human bone. In culture the fungus produced no yeast forms and was less pigmented than two other P. richardsiae isolates. While growth rates were similar, colonial forms differed. Phialides were of two kinds. While both had broad bases and tapered at the tips, only one terminated with a cupulate or rarely a saucer-shaped collarette. Most phialides were hyaline with a few lightly pigmented ones in older cultures. Broth dilution susceptibility testing of the isolates against amphotericin B, miconazole, ketoconazole, clotrimazole, and 5-fluorocytosine showed the fungus was susceptible to miconazole, ketoconazole and amphotericin B at achievable serum levels and resistant to 5-fluorocytosine and clotrimazole. The other isolates were reported to differ in their resistance to miconazole and amphotericin B. Enzyme and salinity studies showed minor difference among the isolates.

Study of the conidial development and cleistothecium-like structure of some strains of Fonsecaea pedrosoi. Comparison with other close Dematiaeae.

The production of twenty-seven strains of Fonsecaea pedrosoi was studied. The denticulate type (asexual reproduction) showed three morphological variations: medium-size, long and sessile forms. These forms can be used to characterize the different strains isolated especially for epidemiological purposes. Only one strain (MR 1335) isolated from a chromomycosis case in Martinique showed a cleistothecium-like structure. This formation was compared to that observed in Phialophora verrucosa, another agent of chromomycosis, and to the cleistothecium of Dictyotrichiella mansonii, the perfect state of Wangiella mansonii which is a saprophyte fungus.