Unusual Verrucous Skin Lesion in Diabetic Neuropathy Following Toe Amputation and Skin Grafting.

Verrucous skin lesions in diabetic neuropathy (VSLDN) are rare and typically occur at weight-bearing sites due to chronic mechanical stress. This case report describes a 35-year-old man with type 2 diabetes mellitus who developed a verrucous lesion on the dorsum of his left foot following toe amputation and skin grafting. Histological analysis identified pseudoepitheliomatous hyperplasia with no evidence of malignancy or human papillomavirus infection. The lesion gradually resolved with the application of maxacalcitol ointment and the use of elastic stockings. This case highlights the importance of recognizing atypical verrucous lesions in patients with diabetes, particularly at non-weight-bearing sites after surgical interventions. Accurate differentiation between plantar warts and verrucous carcinomas is essential for appropriate management. Effective treatment and comprehensive patient education on foot care are crucial for improving outcomes and preventing further complications in patients with diabetes.

Blue Nevus Associated With Acquired Dermal Melanocytosis on the Back.

Dermal melanocytosis includes various congenital and acquired pigmentary disorders characterized by dermal dendritic melanocytes. Blue nevi typically present as papulonodular lesions, whereas other dermal melanocytoses manifest as patches. This report describes a case of a blue nevus associated with acquired dermal melanocytosis on the back of a 46-year-old Japanese woman. The patient presented with a black nodule on a blue-greyish hyperpigmented area on the upper back. Histopathological analysis of the nodule confirmed a common blue nevus, whereas the adjacent hyperpigmented area showed features consistent with acquired dermal melanocytosis. Blue nevi and acquired dermal melanocytoses share a common pathophysiology involving ectopic melanocyte accumulation during embryogenesis. The coexistence of blue nevus and acquired dermal melanocytosis on the back is rare, highlighting the broad spectrum of dermal melanocytosis and the variability of its clinical manifestations. Recognition of such unusual presentations is critical for appropriate diagnosis and management.

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.

Ninjurin1 Deletion in NG2-Positive Pericytes Prevents Microvessel Maturation and Delays Wound Healing.

The formation of mature vasculature through angiogenesis is essential for adequate wound healing, such that blood-borne cells, nutrients, and oxygen can be delivered to the remodeling skin area. Neovessel maturation is highly dependent on the coordinated functions of vascular endothelial cells and perivascular cells, namely pericytes (PCs). However, the underlying mechanism for vascular maturation has not been completely elucidated, and its role in wound healing remains unclear. In this study, we investigated the role of Ninjurin-1 (Ninj1), a new molecule mediating vascular maturation, in wound healing using an inducible PC-specific Ninj1 deletion mouse model. Ninj1 expression increased temporarily in NG2-positive PCs in response to skin injury. When tamoxifen treatment induced a decreased Ninj1 expression in PCs, the neovessels in the regenerating wound margins were structurally and functionally immature, but the total number of microvessels was unaltered. This phenotypic change is associated with a reduction in PC-associated microvessels. Wound healing was significantly delayed in the NG2-specific Ninj1 deletion mouse model. Finally, we showed that Ninj1 is a crucial molecule that mediates vascular maturation in injured skin tissue through the interaction of vascular endothelial cells and PCs, thereby inducing adequate and prompt wound healing.