A 24-year-old female patient came to Japan 3 years ago. 2.5 years ago, she was referred to our department because of recurrent erythema annulare appearing on her trunk and extremities and gradually becoming more and more frequent all over her body. Based on the histopathological findings, anti-acid staining, skin smear test, and anti-PGL-1 antibody, she was diagnosed with group B leprosy. The patient was started on multidrug therapy, and the skin rash disappeared after one year, but two months after discontinuation of oral therapy, the skin rash and neurological symptoms flared up again. After another close examination, she was diagnosed as type 1 leprosy reaction and started prednisolone 15 mg/day, but the neurological disorder remained. Leprosy has become a rare disease, as new Japanese cases are rarely seen. However, it is expected that the number of domestic reports of leprosy may increase in the future as the number of people entering the country from endemic areas increases.

  More than 70% of the elderly facility residents have some form of skin disease, and by disease, dermatomycosis and eczema/dermatitis groups account for by far the largest number of patients. Tinea pedis and tinea unguium are becoming increasingly common among elderly patients as the population ages. Topical antifungal agents are the mainstay of treatment for tinea pedis, while oral medications are predominant in the treatment of tinea unguium. However, in the elderly, complications, multiple medications, and other factors may make oral medications difficult to use, in which case topical medications are preferred. The key to treatment with topical agents is the ability to persevere with topical application over a long period of time until the disease is cured. The key to the treatment of eczema that is based on dry skin is the use of moisturizers. Without a sufficient amount of moisturizer, topical steroid ointments, which are highly effective eczema medications, do not relieve the symptoms and sometimes even exacerbate them. On the other hand, when topical steroids are used, it is important to select the appropriate topical steroid for the area to be treated and the intensity of the disease. Scabies is an easily overlooked condition, and misdiagnosis and prolonged steroid use can result in a transition from normal scabies to keratotic scabies (Norwegian scabies). Because scabies outbreaks in long-term care facilities can be a major problem, it is important to remember that the typical rash of this disease is well established and to always suspect this disease when a patient is refractory to usual eczema treatment.

  Leprosy, an important infectious disease in humans caused by Mycobacterium leprae (Mle), remains endemic in many countries. Of note, the pathogen cannot be cultured in vitro. In addition, Mle grows optimally at 30 to 33℃, while other mycobacteria grow at 37 to 42℃. The molecular bases of these characteristics, as well as the mechanisms remain unknown. Consequently, the analysis of Mle growth and survival is urgently needed to develop novel therapies, such as rapid, simple, and specific methods to detect infection against leprosy. In this study, we functionally characterized in vitro the Mle-DNA gyrase to promote bacterial growth and survival. From our result, we propose that DNA gyrase makes a significant contribution to Mle growth and survival, and DNA gyrase is one of the few clinically validated targets for antimicrobial agents.

  Buruli ulcer disease is a neglected necrotizing and disabling cutaneous tropical illness caused by Mycobacterium ulcerans (Mul). Fluoroquinolone (FQ), used in the treatment of this disease, has been known to act by inhibiting the enzymatic activities of DNA gyrase; however, the detailed molecular basis of these characteristics and the FQ resistance mechanisms in Mul remains unknown. In this study investigated the detailed molecular mechanism of Mul DNA gyrase and the contribution of FQ resistance in vitro using recombinant proteins from the Mul subsp. shinshuense and Agy99 strains with reduced sensitivity to FQs. Furthermore, the interaction between the amino acid residues of WT/mutant Mul DNA gyrase and side chains of FQ was assessed via molecular docking studies. This is the first elaborative study demonstrating the contribution of mutations in Mul DNA GyrA subunit to FQ resistance in vitro.