Restriction fragment length polymorphism (RFLP) in mitochondrial DNA (mtDNA) of clinical and environmental isolates of Sporothrix schenckii was investigated.
Isolates of S. schenckii were classified into 24 mtDNA types (Types 1-24) based on mtDNA RFLP patterns with HaeIII and clustered into two major groups by phylogeny, Group A and Group B. Group A isolates are predominant in South Africa, North America, Central America and South America, while Group B isolates are predominant in Australia, Japan and China.
Based on the mtDNA-RFLP patterns with HaeIII, most environmental isolates morphologically identified as S. schenckii were confirmed to be species distinct from S. schenckii and S. schenckii isolates were few, while all of more than 500 clinical isolates were confirmed as S. schenckii. Therefore, RFLP analysis of mtDNA is essential for the identification of environmental, but not clinical isolates of S. schenckii.

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Cryptococcosis is the third most common deep mycosis in Japan. Cryptococcus neoformans is known to grow in pyres of pigeon feces. Chicken feces in Thailand were tested for whether C. neoformans could be isolated, because there is considerable prevalence of cryptococcal meningitis in patients with HIV in that country. We isolated C. neoformans from chicken feces in as many as at 70% of the villages tested. Chicken as well as pigeon feces were believed to be an origin of infection. We have studied the relation between in vitro virulence and thickness of polysaccharide capsules. Strains with thicker capsules such as YC-11 or YC-5 showed more resistance to macrophage phagocytosis than strains with thinner capsules like YC-27 or YC-13. This finding was consistent with the cytokine dynamic state in mice cryptococcosis. Th1 was dominant in infections with thinner capsule strains, although Th2 was relatively dominant in those with thick capsules. The clinical features of 104 cases with pulmonary cryptococcosis were summarized. Radiological findings of pulmonary cryptococcosis varied depending on the time course of the disease and on immunological status. There were no specific symptoms and signs except for positive glucronoxylomannan. Those in azole class were the most commonly prescribed antifungals. New generation antifungals voriconazole and intravenous itraconazole showed potent clinical efficacy in pulmonary cryptococcosis.

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This article reports two cases of zygomycosis and analyzes the zygomycosis cases reported in the literature in Japan.
Case 1 was a 43-year-old male with malignant lymphoma who presented complications of pneumonia and cerebral bleeding, leading to his death. Autopsy findings showed pulmonary lesions were due to zygomycosis. Cerebral lesion was presumed to be due to zygomycosis without pathological examination. Case 2 was a 52-year-old male with acute lymphocytic leukemia from whom 4 sputum cultures were taken that were positive for Cunninghamella elegans. Combination therapy of itraconazole and amphotericin B (AMPH) was begun, and AMPH was changed to liposomal amphotericin B. During the neutropenic period after receiving premedication for a peripheral blood stem cell transplantation performed for his underlying disease, high fever was recognized and Staphylococcus epidermidis was isolated from the blood culture. Despite the change in antibiotics administered, pneumonia also developed as a complication, causing his death.
Two hundred four cases of zygomycosis have been reported in the literature in Japan: 55 cases were rhinocerebral zygomycosis, including 29 cases with no underlying disease. A premortem diagnosis was made in 34 cases by pathological findings of operation materials or drainage samples, and 24 cases were postmortem.
Pulmonary, disseminated, cardiovascular, gastrointestinal and thyroidal zygomycoses were found in 144 cases, including 66 cases with leukemia. A premortem diagnosis was made in 39 cases and 120 cases were postmortem.
Prognosis of rhinocerebral type was better in operated or drainage cases, and for resected cases in all other types.
Five cases with allergic zygomycosis were all alive.
There were only 14 cases in which isolated fungi were identified (Cunninghamella spp. from 5 cases, Mucor spp. from 2, Rhizomucor spp. from 2, and Rhizopus spp. from 5).

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Deep-seated trichosporonosis is a lethal opportunistic infection in immunocompromised patients. Trichosporon asahii and T. mucoides are the most common strains of fungi that cause disseminated trichosporonosis. Thirteen patients were diagnosed with disseminated trichosporonosis over a 20 year period in Oita Medical University Hospital. The majority of them had underlying hematologic malignancies, for which they received cytotoxic chemotherapy resulting in neutropenia. For the rapid diagnosis of this condition, we developed a novel nested-PCR assay that detected DNA specific for Trichosporon asahii and Trichosporon mucoides in the serum of patients with the condition. In a retrospective study using these serum samples, the specific DNA fragment was detected a few days to a few weeks earlier than blood culture. To treat this infection, we studied the efficacy of granulocyte colony-stimulating factor (GCS-F) alone and in combination with antifungal agents against disseminated trichosporonosis in neutropenic mice. The results suggested that GCS-F might be a useful immunomodulator against Trichosporon infections in neutropenic mice and the therapeutic outcome improved when used in combination with fluconazole. Furthermore our experimental animal model demonstrated that disseminated trichosporonosis is induced by immunosuppresion in hosts with latent trichosporonemia which was detectable by the nested PCR but not by blood culture. We found that there is a critical period for the progression of disseminated trichosporonosis after entry of fungi into the bloodstream.

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A patient with a hematological malignancy is one example of a type of immunocompromised host, and critical opportunistic infections such as mycosis are not rare during medical treatment for such malignancy.
Candidiasis and aspergillosis are typical mycoses and their importance has been recognized widely and great progress attained in their prevention and medical treatment. However, allogenic hematopoietic stem cell transplantation (allo-HSCT) to treat hematological malignancy has spread, and the increase in emerging mycoses such as Fusarium infection is reported.
Fusarium spp. are common soil organisms and important plant pathogens, and have been conventionally known as a causative fungus of superficial mycosis in the dermatology and the ophthalmology domain. Reports of profound or disseminated Fusarium infection are found in immunocompromised hosts with such condition as a hematological malignancy or organ transplant, and have shown an upward tendency in recent years.
The symptoms of disseminated Fusarium infection are shown in many cases with persistent fever refractory to antibiotics and pneumonia, and this is a highly fatal infection which merges fungemia with multiple organ injury such as that in the lung, liver, spleen, kidney, and the heart. Disseminated Fusarium infection has a high rate of isolation in blood cultures, and the rate of diagnosis while a patient is alive is high compared with aspergillosis, zygomycosis, etc.
Despite the administration of anti-fungal drugs following allo-HSCT, two reported cases showing the symptoms of disseminated Fusarium infection finally died. Although definite diagnosis of these cases was made by blood cultures, no medical treatment effect with the anti-fungal drugs was determined. Since the existing antifungals are not expected to cure disseminated Fusarium infection certainly, an early diagnosis and the development of a new antifungal are desired to improve the medical treatment results.

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The systemic mycoses are increasing in importance as opportunistic infections. Cutaneous lesions resulting from systemic mycoses may first alert clinicians to the presence of a life-threatening disorder, or even the presence of an unsuspected immunodeficiency state. Skin involvement is generally uncommon in disseminated aspergillosis, zygomycosis but is more common in systemic candidiasis (candidemia) and cryptococcosis. The blanket terms, hyalohyphomycosis and phaeohyphomycosis, cover the infections caused by diverse fungal opportunists. A variety of manifestations of skin lesions of the systemic mycoses are reviewed. These specific and/or non-specific lesions require early recognition, diagnosis, and aggressive antifungal treatment.

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A questionnaire survey to determine the current status of clinical laboratories on mycological examination was performed in May 2002, and the results compared with data obtained in December 1994. One hundred and sixty seven answers were received in this survey.
The results indicated that the average number of medical technologists in a microbiological laboratory was one for every 168 hospital beds, and the number of clinical specimens examined daily by each technologist was 16 (bacterial) and 3.4 (mycological).
The rate of laboratories prepared a specialized technologist to handle mycological examinations was 10% in both surveys, and laboratories which had a system for mycological examination order were 23.4% (this survey) and 14.1% (prior).
The problems in routine mycological examination were: identification of non-sporulating filamentous fungi, 69.9%; identification of the fungi not previously encountered, 67.5%; and judgement of pathogenicity of the isolates, 66.9%.
Sixty four percent of technologists desired a lecture on the subject of dermatophytes, techniques of mycological examination, dematiaceous fungi, and moniliaceous fungi other than Aspergillus.
The above results indicate to establish a continuous postgraduate education system and reference center readly available to a medical technologist.

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We report two cases of tinea capitis by Microsporum (M) ferrugineum. A two year old boy (case 1) visited our hospital 3 months after his return from Myanmar. About a year later, we observed the same symptom on the scalp of his mother (case 2). In both cases itraconazole was effective clinically and mycologically. In Japan, although M. ferrugineum was the most common organism of tinea capitis before the 1960s, no cases of tinea are found caused by this species nowdays. We believe these cases to have been infected in Myanmar, and suggest the possibility that tinea caused by M. ferrugineum may become a re-emergent infection or an imported fungal disease in Japan.

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Statistical analysis was made of a total of 5530 patients (6798 cases) of dermatophytoses presenting at our private clinic during the period 1992 to 2001. The number of patients and cases represents 8.0% and 9.8% of the entire outpatient population during that time, respectively. Sex ratio (male/female) was 1.5. Among the 6798 dermatophytoses cases, tinea pedis was most frequent (65.8%), followed by tinea unguium (20.7%), tinea cruris (7.2%), tinea corporis (3.9%), tinea manuum (2.4%) and tinea barbae (0.04%). The incidence of tinea unguium increased, whereas that of tinea pedis, tinea cruris, and tinea corporis decreased during this ten year period, and 35.8% of dermatophytoses patients had more than two clinical subtypes simultaneously.
Three thousand seven hundred ninety-five dermatophytes were isolated during the survey.: Trichophyton rubrum (TR) (79.4%), Trichophyton mentagrophytes (TM) (19.5%), Microsporum canis (MC) (0.7%), Epidermophyton floccosum (EF) (0.3%), and Microsporum gypseum (MG) (0.1%).
Compared with our previous analysis reported for the period 1982 to 1991, the frequency of dermatophytoses increased, especially among aged individuals. Of the clinical subtypes, tinea pedis and tinea unguium were higher, but tinea cruris and tinea corporis were lower, and tinea capitis was not seen in the current survey. Among dermatophytes, TR was increased and other types of fungi were decreased. TR was 4.08 times more common than TM; this ratio is higher than our previous report.

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Pathogenic fungi can be identified by growth in special culture medium, colony appearance based on microscopic examination of conidia and hyphae, and by molecular biological techniques. However, these methods are time-consuming and labor-intensive.
We describe a simple method for identification of pathogenic fungi from Sabouraud's glucose agar slant culture, using Fungi-Tape^TM and MycoPerm-Blue^TM. It is rapid and easy, and permits visualization of fungal morphology. Using the Fungi-Tape^TM and MycoPerm-Blue^TM technique, we correctly identified 47 of 66 samples, for a 73.4% concordance with conventional identification methods. It is also noteworthy that slides prepared using this method can be stored for long periods without deterioration.

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