Dermatophytes from animal dermatophytoses were investigated, especially for their teleomorphs and molecular characteristics.
Microsporum canis, M. equinum, M. gypseum, M. nanum, Trichophyton equinum, T. mentagrophytes complex, T. rubrum and T. verrucosum were isolated as the etiological agents of animal ringworm in Japan. They were morphologically and biochemically identified and their perfect states were examined. The teleomorph of M. canis was first obtained and reported as Nanizzia otae in 1975. The isolates of M. canis of which the teleomorph was confirmed were all “-” excepted two Japanese isolates. Mating experiments indicated that the isolates of M. gypseum were “+” or “-” of A. gypseum and A. incurvatum, respectively. Most of the isolates of T. mentagrophytes complex of which a perfect state was detected were A. vanbreuseghemii. One isolate from a monkey was A. simii and one from a rabbit was A. benhamiae. However, the teleomorph remained unknown in many isolates.
Molecular characteristics in random amplification of polymorphic DNA and Southern hybridization analyses were found to be effective to differentiate the species of Microsporum.
Nucleotide sequences of chitin synthase 1 (CHS1) gene of dermatophytes were also analyzed for their phylogenetic relatedness. The phylogenetic analysis revealed four clusters: the first cluster consisted of A. benhamiae, A. simii, A. vanbreuseghemii, T. mentagrophytes var. interdigitale, T. rubrum and T. violaceum; the second of A. fulvum, A. gypseum and A. incurvatum; the third of A. grubyi and A. otae; and the fourth of Epidermaphyton floccosum, providing useful information for the classification and understanding of their evolution.

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We evaluated the minimum period for penetration of Trichophyton mentagrophytes into human stratum corneum using an experimental model of tinea pedis. Fungal elements were applied to the surface of stratum corneum which were obtained from a healthy human heel, and samples were incubated under a designated condition of temperature and humidity. Thirty-five degrees, which is the approximate temperature of the surface of human skin, seemed more suitable for penetration than 27°C. The result also indicated that humidity was a more significant factor than temperature.
In the following examination using T. mentagrophytes and T. rubrum, the minimum period for penetration at 100% humidity was 1 day with the former and 1.5 days with the latter. At 95% humidity, T. mentagrophytes penetrated into human stratum corneum on day 1.5 and T. rubrum penetrated on day 4. Humidity of the 4th interdigital space in daily life was calculated to be below 95% using a hygrothermometer. Therefore, to wash the feet daily can prevent development of tinea pedis.
When we applied fungal elements to a cut side of stratum corneum, fungi penetrated within a day at 100% and 95% humidity. In addition, fungi were able to penetrate at below 85% humidity, which they were unable to do when applied them to the surface side. We stress that minor injury of stratum corneum is also a significant factor of the development of tinea pedis.

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Partial cDNA cloning of a putative membrane transporter protein gene expressed in Sporothrix schenckii and DNA polymorphism of the isolated gene are described here. DNA fragments were isolated from S. schenckii, and the deduced amino acid sequence from one of the fragments contained a region homologous to the conserved sequence of the membrane transporter protein family. 188-bp fragments encoding the homologous region were amplified from many strains of S. schenckii, and were subjected to polymerase chain reaction single strand conformation polymorphism (PCR-SSCP) analysis. The results demonstrated that the strains of S. schenckii were divided into three groups, and several base substitutions among these groups were observed. This finding agreed with the classification of S. schenckii strains based on the mitochondrial DNA diversity, because the three groups were clearly located on the branches of the phylogenetic tree constructed by digestion profiles of mitochondrial DNA with restriction enzymes. The correlation of the results of PCR-SSCP analysis with the mitochondrial DNA diversity might indicate linkage of the mutation of the membrane transporter protein gene with the evolution of S. schenckii, suggesting the protein plays an essential role in S. schenckii.

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A 66-year-old female had a solitary dark-red nodule measuring 1cm in diameter on her left forearm. She often had trauma to her hands and arms. A histopathologic examination demonstrated granulomatous changes in the dermis. Under the high-power magnification yeast-like cells and short toruloid hyphal elements were observed in the granuloma. A few giant cells contained fungal elements. No sclerotic cells were found. On the basis of the histopathologic and mycologic findings, the lesion was diagnosed as a dematiaceous fungal infection caused by Exophiala spinifera. She was treated with oral itraconazole (200mg/day) and topical heat therapy. The lesion was clinically improved within 58-days. However, E. spinifera was still isolated from the excisional specimen 92-days later. We believe that surgical excision is the choice of therapy if the lesion is small.

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A 38-year-old Japanese AIDS patient delveloped papular lesions which rapidly increased in number, eroded and crusted, and spread over not only skin but also the mucosal surface. High fever, sore throat, malaise and hepatosplenomegaly were also noted, and he died despite 2 months of intensive treatment. An autopsy revealed numerous histiocytes infected with Penicillium marneffei in the lymph nodes, liver, spleen, bone marrow, skin, and mucosal surface of the oral cavity to the pharynx. This case is thought to be the first Japanese case of penicilliosis marneffei.

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We investigated the epidemiology of 618 patients of mucocutaneous candidiasis who visited our outpatient clinic between 1993 and 1997. Compared with previous reports in Japan, the incidence of candida intertrigo increased and that of erythema mycoticum infantile decreased. The incidence of “others”, such as nail candidiasis and candidiasis developed under plaster increased. We identified the species of Candida from patients in 496 recent cases, and these species were cultured successfully in 79.2%. As reported by previous authors, a majority or our results were Candida albicans serotype A. We also investigated the risk factors such as diseases or conditions which might be related to immunodeficiency (neoplasm, AIDS) and that might force a patient to restrict himself to bed for a long period (neurological disease). The former was found in 22.7%, and the latter in 23.3% of patients.

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A patient treated with itraconazole (ITCZ) under the diagnosis of Aspergillus flavus-induced chronic hypertrophic pachymeningitis is presented. The reason for the successful cure of this patient was investigated by the pharmacokinetic analysis of serum levels of ITCZ. Concurrently administered digoxin was also investigated for its drug-drug interaction.
The patient (a 75-year-old male) developed ophthalmopathy, and was diagnosed as having A. flavus hypertrophic pachymeningitis by pachymeninx biopsy. After admission, he was treated with FLCZ, AMPH, 5-FC and MCZ. The infection tended to subside with the AMPH administration. Since renal insufficiency was induced by AMPH and the other antifungal drugs were ineffective, daily administration of 200mg of ITCZ was initiated, and the inflammatory signs and symptoms gradually subsided. The symptoms did not recur during the 36 months of itraconazole treatment after discharge, and it was concluded that ITCZ was effective for A. flavus hypertrophic pachymeningitis.
Pharmacokinetic parameters of ITCZ and OH-ITCZ as follows: ITCZ: C_max 93.2ng/ml, T_1/2β 11 hours, AUC_0-24 999ng·h/ml, OH-ITCZ: C_max 159.4ng/ml, T_1/2β 16.2 hours, AUC_0-24 of 1391ng·h/ml. Both ITCZ and OH-ITCZ reached steady states seven days after administration began. The ITCZ and OH-ITCZ levels in serum collected 36 months after the initiation of administration were 452.9ng/ml and 1233.6ng/ml, respectively. C_max and AUC_0-24 of ITCZ and OH-ITCZ on the second day were markedly lower than those in healthy adults reported by Oguchi et al., and hypoalbuminemia observed at administration on that day was considered the most probable cause. It was assumed that the most plausible reason for a successful cure even at a low dose of ITCZ was the increase of distribution to tissue by the increase of the unbound form.
Digoxin was concurrently given to this patient at 0.125mg/day, but the blood digoxin level was not elevated.
Consideration of the blood level of albumin is believed to be important for evaluating the blood concentration of ITCZ.

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Aspergillus fumigatus is an opportunistic pathogen, especially in an immunocompromised host. This fungus grows in a hyphal form in infected tissues; therefore, new tests to examine hyphal susceptibility are needed. In this study, we measured the mycotic activity of miconazole (MCZ) contained in human serum against A. fumigatus using the BioCell-Tracer method. Three serum samples were obtained from the same patient who was injected with 600mg b. i. d. MCZ daily for 2 days. The concentrations of MCZ in the serum sample were 8.8, 3.5, and 1.6μg/ml, respectively.
The serum containing 8.8μg/ml of MCZ inhibited hyphal growth 90 minutes after administration, and the hypha stopped growing. The serum containing 3.5μg/ml MCZ stopped hypha growth 100 minutes after administration, but re-growth of the hypha was observed at this concentration of MCZ. Serum containing 1.6μg/ml did not inhibite hyphal growth, nor did control serum have any inhibitory activity foward hyphae. Based on these results, we conclude that the BioCell-Tracer is a useful method for determining the effects on filamentous fungi of antifungal agents in the serum.

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