Identification of Familial Infections Using Multilocus Microsatellite Typing in Tinea Corporis due to Microsporum canis.

Microsporum canis is a type of dermatophyte that causes zoonotic dermatophytosis in cats and dogs. We report three cases of tinea corporis due to M. canis from a single household with a domestic cat as a pet. The cases included a woman in her thirties (mother), a girl in her teens (older sister), and a girl in her teens (younger sister). Following sudden hair loss in the domestic cat, annular erythema with pruritus and scales appeared on the face, neck, and limbs of the older sister, younger sister, and mother, sequentially; they subsequently visited our hospital. Potassium hydroxide direct microscopy revealed filamentous fungi on all three women. In addition, short-haired colonies with a white to yellowish-white color and extending in a radial manner were found in cultures using a flat plate agar medium. A slide culture with the same medium indicated pointed spindle-shaped macroconidia with 7-8 septa. Therefore, the cases were diagnosed as tinea corporis due to M. canis. Genetic analysis of the cells of the cat and the mother, older sister, and younger sister using multilocus microsatellite typing (MLMT) indicated that all cases were classified into the same genotype, suggesting that the transmission route of these cases was familial. Here, we show that MLMT is useful in identifying the infection route in cases of tinea corporis due to M. canis.

Clinical effectiveness of efinaconazole 10% solution for treatment of onychomycosis with longitudinal spikes.

Onychomycosis with longitudinal spikes in the nail plate has been reported to be refractory to oral drugs as with dermatophytoma. We evaluated the efficacy of 10% efinaconazole solution in the treatment of onychomycosis with longitudinal spikes. Of the 223 subjects who were enrolled in a previous study, a post-hoc analysis of 82 subjects with longitudinal spikes was performed in this study. The opacity ratio of longitudinal spikes was decreased over time from 8.1 to 0.9 at the final assessment. In addition, the longitudinal spike disappearance rate increased early after the application to 81.7% at the final assessment. Therefore, 10% efinaconazole solution can be a first-line drug for longitudinal spikes, which have been regarded as refractory to oral drugs.

Subcutaneous abscesses caused by Trichophyton rubrum in the unilateral groin of an immunocompromised patient: A case report.

A 60-year-old Japanese man presented with multiple subcutaneous nodules in his left groin. Histologically, the nodules consisted of suppurative granulomas and abscesses not involving the hair follicles. Trichophyton rubrum TWCC57922 was detected by fungal culture and polymerase chain reaction (PCR) sequencing of the rDNA genes. We diagnosed these nodules as deeper dermal dermatophytosis, a rare form of invasive dermatophytosis. He was treated with terbinafine. We compared these findings with previous reports of deep dermal dermatophytosis.

Dermatoscopy of folliculosebaceous cystic hamartoma.

A 29-year-old Japanese man presented to our institution with a nodule on his nose that had increased in size since childhood. Physical examination indicated the presence of an elastic, firm, pedunculated red nodule measuring 15 mm in size. Dermatoscopic examination of the nodule indicated a yellowish-white network, yellowish-orange dots/globules at its center, and a pinkish-white structureless peripheral area. Histopathological examination of an excisional biopsy specimen showed a dilated infundibulocystic structure with sebaceous lobules proliferating radially, surrounded by fibrous stroma. Moreover, mature adipocytes and small vessels were noted in the stroma. Based on these histopatho-logic findings, the patient was diagnosed with folliculosebaceous cystic hamartoma.

Histopathological investigation of clinically non-affected perilesional scalp in alopecias detected unexpected spread of disease activities.

Histopathological comparison between clinically affected and intact regions in alopecia patients has been considered to facilitate better understanding of the pathophysiology of ongoing disease. Theoretically, adjacent intact regions should provide ideal controls as they should share close histological characteristics, however, to what extent clinically non-affected neighboring regions maintain their pathological integrity has not been fully assessed. The goal of this study is to delineate histopathological characteristics of clinically intact perilesional regions in the patients with various forms of alopecia. Transverse sections of 4-mm punch biopsy at the levels of isthmus and suprabulbar portion were obtained from seemingly unimpaired perilesional scalp of 50 Japanese alopecia patients (16 alopecia areata [AA] multiplex, 19 scarring alopecia [SA], 15 other conditions) and subject to histopathological investigation. Initial screening detected decrease in anagen (anagen : telogen ratio = 82.4:17.6) when compared with previously reported standard hair counts in normal Asian scalp. This finding prompted further investigation. Unexpectedly, 33 (66%) specimens demonstrated some microscopic abnormalities, 10 (62.5%) AA specimens showed increase in telogen ratio, vellus hair count and miniaturization, while perifollicular inflammatory cell infiltration was detected in 5 (26.3%) SA cases. Exclusion of histologically affected specimens yielded average hair count numbers resembling those reported in Koreans, supporting the pathological integrity of selected samples and, more importantly, indicating normal hair counts in east Asians. These findings indicated a less recognized significance of histopathological investigation of clinically non-affected perilesional scalp in alopecias for better assessment of the spread of disease activities, which should enable better management of hair loss conditions.

Histopathological insights into hair loss in Cronkhite-Canada syndrome: diffuse anagen-telogen conversion precedes clinical hair loss progression.

Cronkhite-Canada syndrome (CCS) is a rare disorder characterised by gastrointestinal polyposis and ectodermal changes, represented by extensive alopecia. Detailed histopathological investigations of alopecic lesions in two female CCS patients with severe hair loss revealed a marked increase in telogen hair follicles with no sign of loss or of the minaturisation or atrophy of hair follicle structures and the absence of inflammatory change, despite severe inflammation in the gastrointestinal tract. These findings suggested that hair regrowth can be expected without systemic corticosteroids, if they are not necessary for treatment of the gastrointestinal tract, and that anagen-telogen transition is an early event preceding clinical hair loss in CCS.