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.

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.

Appropriate radial clearance of ceramic-on-ceramic total hip prostheses to realize squeeze-film lubrication.

OBJECTIVE: Estimation of appropriate radial clearance of ceramic-on-ceramic total hip prostheses to realize squeeze-film lubrication. BACKGROUND: Some clinical results show that severe wear occurs at ceramic-on-ceramic interfaces of total hip prostheses if the design parameters are improper. Appropriate design is required to realize the optimum lubrication of joint prostheses. DESIGN: Squeeze-film thickness of total hip prostheses with different radial clearances was numerically estimated under the physiological conditions of normal walking. METHODS: The changes in the fluid film thickness between ceramic balls and a ceramic cups with radial clearances of various values from 10 to 80 microm were numerically estimated under the assumption of normal walking conditions by means of elastohydrodynamic squeeze-film lubrication theory including the three-dimensional theory of elasticity. RESULTS: The minimum film thickness remained over 0.02 microm during a few walking steps with a radial clearance under 20 microm and a head diameter of 28 mm. On the other hand, the fluid film was squeezed out during a few steps when the radial clearance was greater than 30 microm. CONCLUSIONS: Squeeze-film lubrication can be realized in a ceramic-on-ceramic total hip prosthesis if the radial clearance is smaller than 20 microm on a head of 28 mm diameter. RELEVANCE: Fluid film lubrication is necessary to prevent the severe wear of ceramic joint prostheses. The present investigation shows which radial clearance of ceramic-on-ceramic hip prostheses is appropriate for squeeze-film lubrication under physiological conditions in daily action.