The second nationwide surveillance of antibacterial susceptibility patterns of pathogens isolated from skin and soft-tissue infections in dermatology departments in Japan.

The present study compared trends in antimicrobial resistance patterns in pathogens isolated from skin and soft-tissue infections (SSTIs) in Japan with those of a nationwide survey conducted in 2013. Three organisms that caused most of the SSTIs were collected from 12 dermatology departments in medical centers and 12 dermatology clinics across Japan between April 2019 and August 2020. A total of 390 strains, including 267 Staphylococcus aureus, 109 coagulase-negative staphylococci (CNS), and 14 Streptococcus pyogenes strains were submitted to a central laboratory for antimicrobial susceptibility testing. Patient demographic and clinical information was collated. Methicillin-resistant S. aureus (MRSA) was detected in 25.8% (69/267) of the S. aureus strains. The prevalence of MRSA between the present study and the 2013 survey did not differ significantly. Furthermore, there were no significant differences in MIC values and susceptibility patterns of the MRSA strains to other agents, regardless of a history of hospitalization within 1 year or invasive medical procedures. Methicillin-resistant CNS (MRCNS) was detected in 48.6% (53/109) of CNS isolates, higher than the 35.4% prevalence in the 2013 survey. This difference could be attributed to the heterogeneity in the members of the MRCNS, which comprises multiple staphylococci species, between the 2013 and 2019 surveys. However, it was noted that the susceptibility profiles of the MRCNS to each antibiotic were not significantly different from those identified in the 2013 survey. Most strains of S. pyogenes were susceptible to each antibiotic, similar to the 2013 survey. Continuous monitoring of trends in pathogen and susceptibility profiles is important to advise local public health efforts regarding the appropriate treatment of SSTIs.

Lymphoepithelioma-like carcinoma of the skin with potential for sweat glandular differentiation.

Lymphoepithelioma-like carcinoma of the skin (LELCS) is a cutaneous malignancy with histopathological resemblance to lymphoepithelioma of the nasopharynx. Its histogenesis remains unknown, and few cases showing skin appendage differentiation have been reported to date. We present the case of a 77-year-old Japanese male with an asymptomatic red nodule on his left cheek. Because the histopathological study revealed focal growth of tumor cells lacking connections with the epidermis and marked lymphocytic infiltration surrounding the neoplastic cell nests, the case was diagnosed as LELCS. On immunohistological staining, the neoplastic cells were positive for carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA), multi-cytokeratin (CK), CK6, CK18, and CK19. On the basis of these results, we suggested that skin appendage differentiation, particularly sweat glandular differentiation, was present in this case.