Trichophyton tonsurans is now a major cause of tinea capitis, affecting both children and adults. The characteristic lesions are pruritic, scaling patches with black dots; Wood's light examination is negative. Microsporum canis and Microsporum audouini, formerly the most frequent causes of tinea capitis, predominantly affect children and are Wood's light positive. Lesions caused by M. canis are inflammatory, while those of M. audouini are scaly. All three organisms respond to griseofulvin.
断发毛癣菌现在是头癣的主要病因，影响儿童和成人。其特征性损害为瘙痒性、有黑点的鳞屑斑；伍德灯检查为阴性。犬小孢子菌和奥杜盎小孢子菌以前是头癣最常见的病因，主要影响儿童，伍德灯检查为阳性。犬小孢子菌引起的损害为炎症性，而奥杜盎小孢子菌引起的损害为鳞屑性。这三种病原体对灰黄霉素均有反应。
