We report four cases of sporotrichosis in a 71-year-old man, a 56-year-old woman, a 68-year-old man, and a 73-year-old man. Using gene analysis in the 68 and 73 year old men, the causative organism was identified as Sporothrix globosa. In the 73-year-old patient, treatment with itraconazole was not very effective, so we switched to potassium iodide, followed by excision of all lesions. Potassium iodide was effective in the other 3 patients.
Based on genetic analysis, studies have confirmed that potassium iodide and hyperthermia are effective in Japan because the causative agent of sporotrichosis (most frequently Sporothrix globosa) does not grow at 37°C and shows low susceptibility to itraconazole.
Dermatologists should be aware of the advances in mycology, including the role of genetic testing in effectively treating mycoses.
Two unique cases of melanocytic nevus with satellite lesions are reported. The first was a 33-year-old woman who had had a melanocytic nevus on her left hip since she was an elementary student. A previous physician had noted that small pigment spots had increased around the lesion. The main lesion, as well as a satellite lesion, showed an intradermal type of melanocytic nevus. Nevus cells were found in the lymphatic vessels of the satellite lesion. The second case was a 5-year-old boy who had had a pigment spot on his left sole since infancy. The lesion had grown bigger and multiple small pigment spots appeared around it by about 2 to 3 years of age. The main lesion was diagnosed as a compound type melanocytic nevus, and a satellite lesion was diagnosed as a junctional type melanocytic nevus. It appears that the satellite lesion had appeared due to lymphogenous dissemination of nevus cells from the main lesion in the first case and due to melanoblasts, which are invisible to the naked eye, turning into nevus cells and becoming visible at multiple sites at a different time in the second one.