We propose a new method for evaluating the severity of pincer nail, in which the narrowed nail width ratio (NNWR) is calculated based on the measurements of actual nail width, distance between the distal lateral nail edges, and apparent proximal nail width. The method revealed that the average distal NNWR of the big toenails of 24 healthy volunteers was 80.5%, whereas that of 24 patients with pincer nail averaged 32.4%, indicating a significant difference between the two groups. Furthermore, the average increase in NNWR in six weeks after the correction therapy using a superelastic wire was 23.2 points, comparable to the clinical improvements of the overcurvature. In conclusion, this evaluation method using NNWR enabled objective judgement of not only the severity of pincer nail, but also the therapeutic effects of the correction treatment.

We report a case of 40-year-old woman with a Bednar tumor arising on the upper left chest. The lesion was a 45×21 mm, slightly reddish plaque with bluish pigmentation in some areas. A wide local excision followed by split-thickness skin graft was performed. Histopathological examination of the resected specimen revealed proliferation of spindle-shaped cells arranged in a tight storiform pattern, admixed with melanin containing dendritic cells. In the lower part of the tumor, sinusoid-like slits lined by the pleomorphic cells were seen. Scattered multinucleated giant cells were also observed. Immunohistochemically, most of the spindle-shaped cells were positive for CD34 and negative for S-100 protein. The melanin containing dendritic cells were positive for S-100 protein. Cytogenetic analysis identified a gene fusion of exon 2 of platelet-derived growth factor beta (PDGFβ; 22q13) to exon 34 of collagen type I alpha 1 (COL1A1; 17q22). The present case demonstrates a close histogenetic relationship between Bednar tumor and giant cell fibroblastoma.

An 83-year-old woman suffering from myelodysplastic syndrome and autoimmune hemolytic anemia who had been treated with oral prednisolone presented with redness, swelling, nodules, and subcutaneous indurations on the left lower leg. Mycobacteria were cultured from both a biopsy specimen and a discharge from a skin lesion and identified as Mycobacterium (M.) immunogenum by DNA sequence analysis of the 16S rRNA gene. The results of a DNA-DNA hybridization test suggested that the bacteria were M. abscessus. M. immunogenum was characterized as a new species very close to M. chelonae and M. abscessus in 2001. To our knowledge, infections due to M. immunogenum, including skin infection, have not previously been reported in Japan. However, it is possible that they have been erroneously reported as either M. chelonae or M. abscessus infections.