Yumi Shiraki

Genotype Analysis of the Variable Internal Repeat Region in the rRNA Gene of Trichophyton tonsurans Isolated from Japanese Judo Practitioners

Tinea capitis due to Trichophyton tonsurans is currently epidemic among Japanese Judo practitioners. T. tonsurans has seven genotypes in a variable internal repeat (VIR) region of the rRNA gene. All 101 isolates obtained from Japanese Judo practitioners had the identical genotype. This suggests that a specific genotype strain occurs throughout Japan.

Commonly affected body sites in 92 Japanese combat sports participants with Trichophyton tonsurans infection

Outbreaks of Trichophyton tonsurans infection constitute one of the serious problems among combat sports practitioners in Japan. To facilitate the diagnosis of individuals at risk, we undertook a study to determine which body sites are most commonly infected. We reviewed medical data, hairbrush culture results and questionnaire information from patients with T. tonsurans infection who were admitted to the dermatology clinic of Juntendo University hospital from 2000 to 2004. The study included 92 patients (87 males), aged 6–38 years (mean age: 18.4 years old). Eighty‐nine patients were judo practitioners and three were wrestlers. Twenty‐eight patients (30.4%) were asymptomatic carriers. In 64 patients, 51 patients (55.4%) with tinea corporis, 27 patients (29.3%) with tinea capitis, and/or one patient (1.1%) with tinea manuum were seen. Tinea corporis was observed on the forehead, auricles, nape of the neck, bilateral shoulders, left side of the upper chest, both elbows, back of the left hand to the wrist and both knees. Tinea capitis was most common in the occipitonuchal region at the hairline and in the temporal and frontal regions, at both auricles. Initial screening of these sites might facilitate the identification of the infection especially in judo practitioners.

Treatment of dermatophyte onychomycosis with three pulses of terbinafine (500 mg day-1 for a week).

We assessed the safety and efficacy of pulse therapy with terbinafine tablets in 55 patients with dermatophytic onychomycosis. One pulse consisted of oral terbinafine tablets (500 mg day−1) given for 1 week usually followed by a 3‐week interval. This regimen was repeated twice. Topical 1% terbinafine cream was applied daily. Efficacy was assessed based on both clinical and mycological examinations 1 year after treatment initiation. We observed a complete cure in 41 patients (74.5%), marked improved in three patients (5.6%), slight improvement in three patients (5.6%) and drop out in six patients (10.7%). Two patients (3.6%) discontinued terbinafine because of gastrointestinal disturbance (one patient) and drug‐induced eruption (one patient). No patient had abnormal laboratory findings, including liver function tests. In summary, a regimen of three pulses of terbinafine therapy given daily for 1 week in combination with topical application of terbinafine cream appears to be safe and effective in treating dermatophytic onychomycosis and offers advantages in convenience and cost‐effectiveness compared with continuous dosing.

Management and follow-up survey of Trichophyton tonsurans infection in a university judo club

The prevalence of Trichophyton tonsurans infection of the scalp in members of a university judo club (combat sport) was investigated over a 3.5‐year period using a questionnaire survey and an assay based on fungal culture by the hairbrush method. In November 2002, 11 (35%) of 31 athletes were found to be positive for T. tonsurans infection by the hairbrush method and provided treatment with oral and topical antifungal agents according to a prescribed protocol. All the infected subjects became culture‐negative following this treatment. We continued to conduct screening examinations every year in the month of April, when new university enrolment occurs. During three‐and‐a‐half years of follow‐up, there have been no outbreaks of the infection among the members of the university judo club. There were some positive culture results among the newly enrolled students, but these cases also became culture‐negative with treatment. No re‐infection has been noted after graduation among the club members who had been educated about and treated for the infection. Our findings indicate that the spread of T. tonsurans infection in sports clubs can be controlled by regular mass screening examination, therapy and measures at regular intervals to prevent the infection.

Real-time PCR TaqMan assay for detecting Trichophyton tonsurans, a causative agent of tinea capitis, from hairbrushes

Tinea capitis caused by Trichophyton tonsurans is currently an epidemic in the United States, Europe, and Japan, and the cultivation of this microorganism is necessary for a definitive diagnosis. We recently developed a real-time PCR TaqMan assay as a culture-independent method for the rapid detection of T. tonsurans from hairbrushes.

A case of lymphangitic sporotrichosis occurring on both forearms with a published work review of cases of bilateral sporotrichosis in Japan

The patient, 56‐year‐old man who was working as a clerk and a farmer, presented with nodules that had appeared on the dorsa of both his hands 3 months earlier. At the first examination, there were multiple dark‐red nodules scattered on the fingers, dorsa and wrists of both hands. The nodules were up to 3 cm in diameter and had crusts in the incenters. The patient was suspected to suffer from prurigo and was subsequently treated with topical steroid, but the nodules did not respond. Therefore, a skin biopsy and fungal culture were performed, and the patient was finally diagnosed as having bilateral multiple sporotrichosis. He was then successfully treated with local thermotherapy and oral potassium iodide. Bilaterally‐distributed lymphangitic sporotrichosis is very rare and often difficult to diagnose. Careful attention is required to avoid misdiagnosis.

Combination of pulse therapy with terbinafine tablets and topical terbinafine cream for the treatment of dermatophyte onychomycosis: a pilot study.

We performed a pilot study to assess the safety and efficacy of pulse therapy with terbinafine tablets in 66 patients with dermatophyte onychomycosis. One pulse consisted of oral terbinafine tablets (500 mg/day) given for 1 week followed by a 3‐week interval. Topical 1% terbinafine cream was applied daily. The number of pulses was determined by the extent of improvement in the affected nails and by the patients requests, up to a maximum of six pulses. Efficacy was assessed based on both clinical and mycological examinations 1 year after treatment initiation. We observed a complete cure in 51 patients (77.3%), marked improvement in five patients (7.6%), improvement in five patients (7.6%) and slight improvement in one patient (1.5%). Four patients (6.0%) showed no change. In the patients who were completely cured, the average number of pulses used was 3.7 ± 1.4 pulses and the treatment duration was 3.3 ± 1.6 months. Nine patients experienced adverse effects, consisting of gastrointestinal disturbance (eight patients) and drug‐induced eruption (one patient). There were no abnormal findings in the laboratory tests, including liver function tests. In summary, terbinafine pulse therapy in combination with topical application of terbinafine cream appeared safe and effective in this pilot study.

Candida albicans abrogates the expression of interferon‐γ‐inducible protein‐10 in human keratinocytes

Candida albicans is the predominant causative agent of human cutaneous candidiasis. Epidermal keratinocytes play an important role in the cutaneous immune response through the production of cytokines and chemokines, including IFN-gamma-inducible protein 10 (IP-10). Here, we investigated the influence of C. albicans infection on IP-10 production by normal human epidermal keratinocytes (NHEK) in vitro. Our results showed that IFN-gamma-stimulated NHEK showed enhanced IP-10 mRNA and protein expression; this expression was downregulated by C. albicans infection. Candida tropicalis also impaired IFN-gamma-induced IP-10 expression, but Candida glabrata did not. Heat-killed C. albicans did not impair IFN-gamma-induced IP-10 expression. We found that coincubation of NHEK with live C. albicans without cell-to-fungi contact impaired IFN-gamma-induced IP-10 mRNA and protein expression in NHEK, suggesting the role of soluble factors derived from live C. albicans in this impairment. Enzyme-linked immunosorbent assay analysis revealed that C. albicans and C. tropicalis could produce marked levels of prostaglandin (PG) E(2), while C. glabrata produced low levels of this prostaglandin. Treatment with E-series prostaglandin receptor antagonists, AH6809 and AH23848, restored IFN-gamma-induced IP-10 expression in C. albicans-infected NHEK. Thus, Candida-derived PGE(2) may impair IFN-gamma-induced IP-10 expression in human keratinocytes and may play a role in the pathogenesis of cutaneous candidiasis.

Case of tinea capitis caused by Trichophyton mentagrophytes (molecular type Arthroderma benhamiae): Prevalence of a new zoonotic fungal infection in Japan

Dear Editor, We describe herein a case of tinea capitis caused by Trichophyton mentagrophytes (molecular type Arthroderma benhamiae) and suggest that infection caused by A. benhamiae-related T. mentagrophytes has already spread widely in Japan. A 6-year-old girl, living in Tokyo, was referred to our clinic for evaluation of a scalp eruption that had appeared 1 month earlier. Despite treatment with systemic griseofulvin, the symptoms had worsened. On initial examination, we observed four nodules on the scalp, with hair loss. One nodule was on the parietal region, two were on the regio occipitalis capitis, and the fourth was on the regio temporalis capitis. One of the nodules, on the parietal region, was the size of a quail’s egg and showed pronounced swelling, with spongy and indurated areas exuding pus and with adherent crusts (Fig. 1). On the child’s face and trunk, there were many pruritic, erythematous, crusted lesions, which had been scratched. Examination of hair shafts by direct microscopy showed ectothrix tinea capitis spores outside the hair shaft. As no fungal element was observed on the face and trunk, the eruptions outside the scalp were considered dermatophytid. A colony cultured on Sabouraud dextrose agar from these lesions produced flat, milky-white, powdery colonies with ray-like margins. On slide culture of the isolates, numerous circular to tear-shaped microconidia, spirals and a few club-shaped macroconidia were observed. Based on macroscopic and microscopic characteristics (Fig. 2), we identified the isolate as T. mentagrophytes, a classification that includes multiple species, including three teleomorphs. The chitin synthase 1 (CHS1) sequence from the clinical isolate was investigated to determine its similarity to other dermatophyte sequences. Its sequence proved to have more than 85% similarity with sequence of the other dermatophytes examined. Moreover, the sequence similarity between the clinical isolate and known A. benhamiae isolates exceeded 99%. As the clinical isolates CHS1 sequence was essentially identical to that of A. benhamiae and distinct from those of Arthroderma simii, Arthroderma vanbreuseghemii and Trichophyton interdigitale, the isolate was highly suggested to be A. benhamiae by molecular analyses. Trichophytin skin test was not carried out. We diagnosed kerion celsi with dermatophytid and treated the patient with a combination of oral

A case of Trichophyton tonsurans infection in which incubation time can be estimated

Dear Editor, Trichophyton tonsurans is a well-known causative organism of tinea capitis in the West.1 In Japan, outbreaks of T. tonsurans infection among wrestlers and judo participants have rapidly increased since approximately 2001.2 Because judo is a national sport and a large population in Japan participates in judo, this disease poses a major public health problem for this country. We recently treated a case of T. tonsurans infection at a clinic in Tokyo that suggested that infection can spread by ordinary household contact and that allowed us to estimate the incubation time of the infection. In treating this case, we realized the pressing need to establish countermeasures against T. tonsurans infection in Japan. The patient was a 13-year-old junior-high school girl from Tokyo with no sports history. She visited our clinic on 21 September 2004, complaining of round, erythematous, scaly macules on the abdomen and left thigh. Two erythematous macules with mild itching had first appeared on the abdomen and left thigh about 1 week earlier and had gradually assumed a round shape. Medical and family history were uneventful. On the first examination, we noted an erythematous macule 2 cm in diameter with a raised border on the abdomen which was surrounded by three relatively small erythematous macules suggestive of satellite lesions. On the extensor surface of the left thigh, we observed another erythematous macule 2.5 cm in diameter with a well-defined border associated with fine scales and with a center that showed slight clearing (Fig. 1). Microscopic examination of potassium hydroxide specimens prepared from the eruptions on the abdomen and left thigh revealed many hyphae. Fungal specimens were cultured on Sabouroud’s glucose agar, and an isolate was identified as T. tonsurans using direct DNA sequencing of polymerase chain reaction amplication.3 Scalp hairs were negative for fungi by the hairbrush method. The patient was given a diagnosis of tinea corporis and treated with oral terbinafine and liranaftate cream. This case suggests that T. tonsurans can be transmitted from person to person by normal household exposure within a 4-week period, in the absence of extensive physical contact, such as judo wrestling. The patient had stayed with her mother’s family in Akita Prefecture, a northern part of the Honshu District of Japan, from 7–21 August during summer holidays. Her mother’s family consisted of three members including her 16-year-old cousin, who was a member of his high-school judo club. The cousin visited a dermatology clinic regularly for treatment of tinea corporis. His doctor had diagnosed tinea corporis on the face without performing a culture and was treating the boy only with miconazole cream. It was known that tinea was prevalent