Primary Cutaneous Gamma-Delta T-Cell Lymphoma Initially Diagnosed as Subcutaneous Panniculitis-like T-Cell Lymphoma with Dermatomyositis.

Primary cutaneous gamma-delta T-cell lymphoma (CGD-TCL) is a rare cutaneous lymphoma. Panniculitis-like T-cell lymphoma (SPTCL) has a better prognosis than CGD-TCL. SPTCL is sometimes associated with autoimmune disease. A 64-year-old Japanese female with a history of dermatomyositis presented with subcutaneous nodules on the upper extremities and exacerbated dermatomyositis. A skin biopsy showed lobular panniculitis, a vacuolar interface change, and a dermal mucin deposit. Fat cells rimmed by neoplastic cells, fat necrosis, and karyorrhexis were observed. The atypical lymphoid cells showed CD3+, CD4-, CD8+, granzyme B+, CD20-, and CD56-. Polymerase chain reaction analysis demonstrated a T-cell receptor rearrangement. The patient was initially diagnosed with SPTCL, so the dose of prednisone was raised from 7.5 to 50 mg daily (1 mg/kg). After one month, erythematous nodules regressed, and muscle symptoms improved. Subsequently, prednisone was tapered, and cyclosporin A was added. After one year, the patient remained symptom-free and continued taking 7.5 mg prednisone and 100 mg cyclosporin A daily. Afterward, we immunostained skin samples with antibodies against TCR-ß and δ and found positive TCR-δ and negative TCR-ß. Therefore, we corrected the diagnosis to CGD-TCL, although the clinical course and the presence of dermatomyositis were reminiscent of SPTCL.

Evolution and virulence of Panton-Valentine leukocidin-positive ST30 methicillin-resistant Staphylococcus aureus in the past 30 years in Japan.

Methicillin-resistant Staphylococcus aureus (MRSA) includes hospital-acquired MRSA (HAMRSA) and community-acquired MRSA (CA-MRSA). Panton-Valentine leukocidin (PVL)-positive multilocus sequence type 30 (ST30) MRSA is one of worldwide CA-MRSA, which has also persisted in Japan since the 1980s. However, unexpectedly, it was not the same ST30 clone throughout. Before 2000, it was HA-MRSA with spa43 and ψSa3sea (phage Sa3 carrying the sea gene) and only one PVL-positive MRSA in Japan; in the 1980s, ST30 MRSA accounted for 23.5% of HA-MRSA, showed multidrug resistance, had high MICs for oxacillin and imipenem, and caused decubitus and pneumonia in hospitalized patients. A dynamic clonal change (spa43/ψSa3sea→ spa19) occurred around 2000-2002. A rare spa43/ψSa3sea/SCCmecI-IE25923 genotype also emerged. After 2002, the prevalent spa19 clone was CA-MRSA; it accounted for only 0.3% (or less) of MRSA in hospitals but 7.6% of CA-MRSA. Since 2007, PVL-positive CA-MRSA with other ST types (such as ST8, ST22, and ST59) also emerged in Japan, albeit at a low frequency. ST30/spa19 CA-MRSA occasionally caused severe invasive infections and a novel ST1335/spa19 genotype emerged. These ST30/spa19 CA-MRSA and variants were identified by pulsed field gel electrophoresis. Further analysis revealed that PVL-positive ST30/spa19 CA-MRSA is a highlyvirulent, successful clone, having a potential of clonal expansion.

Bacteriological study of epidermal cysts.

The aim of this study was to determine whether bacterial infection plays a significant role in the inflammatory process of epidermal cysts. Samples from 152 patients (115 cases of inflamed and 37 of uninflamed epidermal cysts) were subjected to aerobic and anaerobic bacterial culture and the isolates were investigated. The rate of bacterial growth and the recovered anaerobes were significantly greater in the inflamed than the uninflamed epidermal cysts. However, it is difficult to determine whether recovered isolates from epidermal cysts represent "infection" or "colonization". In conclusion, this study revealed the predominance of anaerobes in inflamed cysts, strongly suggesting that anaerobes play a role in the inflammatory process.

Topical antibiotic treatment of impetigo with tetracycline.

Forty-nine children aged 0.2-13 years with bullous and eroded lesions, from which Staphylococcus aureus was isolated, were diagnosed with impetigo and entered into a randomized, open-labeled trial of topical oxytetracycline hydrochloride (tetracycline) compared with a combination of topical tetracycline and oral antibiotics. After one week of topical tetracycline treatment, 22 of the 28 patients were clinically cured, and the remaining six patients had improved. In the other treatment group, 14 patients of 21 were clinically cured and 7 patients improved by the combination of topical tetracycline and oral antibiotics. There were no significant differences between the two groups. Therefore, the present study suggests that topical tetracycline treatment is effective for the treatment of impetigo.