A Chinese-Japanese Boy with Black Dot Ringworm Due to Trichophyton Violaceum

In 2006, a 4-year and 8-month-old Chinese-Japanese boy presented with multiple patchy alopecia lesions with black dots on his scalp and erythematous macules on his face, nape, and right hand dorsum. After frequent visits to Dalian, China, he developed these symptoms a year prior. A diagnosis of tinea capitis and tinea corporis was made based on potassium hydroxide (KOH) examination of hair and scales, and the fungus Trichophyton violaceum was identified as the causative organism through culture, microscopic examination, and molecular biology techniques. This case was notable as T. violaceum infections are rare in Japan, and the boy likely contracted the infection in China. Additionally, the formation of conidia by T. violaceum is uncommon, with only five reported cases in Japan, including this one. The document also described the use of Fungi-tape and MycoPerm-blue as methods for visualizing T. violaceum conidia formation.