To clarify the association of clinical and prognostic features with dermatomyositis (DM)specific autoantibodies (Abs) in adult Japanese patients with DM.

A 75-year-old Japanese man presented with pruritic blisters and macules on his trunk and extremities. He had been on hemodialysis for 4 years because of chronic renal failure, and in recent months, a polymethylmethacrylate membrane had been used for dialysis. After a change in dialysis membrane to a cellulose triacetate membrane, pruritic tense blisters developed on the extremities in combination with marked blood eosinophilia. Physical examination showed erythematous macules and tense blisters on the trunk and extremities. A biopsy specimen of an erythematous macule showed subepidermal vesicles and eosinophils that attached to the dermal-epidermal junction. Serum level of eosinophilic cationic protein was elevated. From clinical, histological, and immunological findings, a diagnosis of bullous pemphigoid was made. New blisters continued to erupt during the period in which the patient used the cellulose triacetate membrane dialyzer, and even after the use of clobetasol propionate. It resolved only after the patient came back to the use of a synthetic membrane dialyzer. We discontinued the use of clobetasol propionate, and neither bullous eruptions nor blood eosinophilia recurred. These observations suggest that cellulose membrane may be involved in the development of bullous pemphigoid through activation of eosinophils in the blood and the skin lesion, as in the present case.

Dear Editor, Mycobacterium chelonae is a rapidly growing mycobacterium that causes illnesses ranging from disseminated cutaneous infection, localized cellulitis, abscess, osteomyelitis, to catheter infection in immunocompetent or immunosuppressed patients. 1 Recent studies have shown that isolates of M. chelonae are usually susceptible to clarithromycin, 1,2 and thus it has been the drug of choice for cutaneous M. chelonae infection. 3 However, there have been case reports of clarithromycin resistance in patients with M. chelonae infection. [4][5][6][7] We report a case of cutaneous M. chelonae infection which exhibited resistance to clarithromycin and was successfully treated with roxithromycin.A 36-year-old, previously healthy, Japanese woman presented in April 2006 with a 4-week history of a painful subcutaneous nodule on the right upper arm. She had no previous history of trauma. Physical examination revealed a firm subcutaneous nodule 3 cm in diameter on the outside of her right upper arm. There was no discoloration of the overlying skin. Magnetic resonance imaging (MRI) of the nodule demonstrated a subcutaneous mass with similar signal intensity to muscle on T1-weighted images (Fig. 1), and a high signal on T2-weighted images. Postcontrast T1-weighted images demonstrated intense enhancement of the subcutaneous nodule, suggesting a hypervascular tumor. A presumptive clinical diagnosis of a subcutaneous tumor such as angioleiomyoma was made, and the tumor was excised. Histological examination of the tumor revealed a dense infiltrate of neutrophils, monocytes and lymphocytes ( Fig. 2a). A few granulomas with multinuclear giant cells were also seen ( Fig. 2b). A diagnosis of an abscess with an infectious granuloma was suggested, but Ziehl-Neelsen, Gram, and periodic acid-Schiff staining did not reveal any microorganisms. Two months later, a subcutaneous nodule recurred beside the excision site. A biopsy specimen of the nodule revealed the same histological findings. A culture of the nodule revealed a rapidly-growing Mycobacterium, which was identified as M. chelonae by DNA-DNA hybridization. Susceptibility testing of the organism was not performed. Oral minocycline, 100 mg twice daily, was started and subsequently discontinued due to gastrointestinal symptoms. After identification of the organism, she was treated with oral clarithromycin, 200 mg twice daily, for 5 weeks but the subcutaneous nodule enlarged. The treatment was changed to oral roxithromycin, 150 mg twice daily, which resolved the nodule within the first 4 weeks. Figure 1. Transverse magnetic resonance imaging (MRI) of the nodule on the right upper arm. T1-weighted imaging demonstrates a mass with similar signal intensity to muscle in the subcutaneous fat (arrow).