Oppositely, antrhropohilic organisms classically affect occluded areas of the skin or areas of trauma. The classical and more common clinical variety in which annular lesions have active, erythematous and spreading borders with central clearing is called in common parlance ringworm and scientifically, tinea circinata . When any of these dermatophyosis is treated with corticosteriods, the lesions take on atypical appearance and lose the characteristic scaling of tinea corporis. Patches, papules, or small nodules appear. Tinea profunda refers to the appearance of subtaneous abscess, which are frequently associated with T. mentagrophytes .
Topical therapy is useful in cases of noninflammatory lesions.
Rarely a biopsy is required for the diagnosis of this condition. Classically, fungal elements are seen in the stratum corneum with PAS, silver methenamine or other fungal stain. Laboratory Direct examination Superficial scraping from the spreading border of the lesion is recommended. If vesicular lesions predominate, the roof of the blister should be taken. Definition Tinea cruris is an acute or chronic infection of the groin, perineum, and perianal region.