title: Dermatophyte infections mimicking other skin diseases: a 154-person case survey of tinea atypica in the district of Cagliari (Italy).
abstract: BACKGROUND
  Although usually simple, the diagnosis of dermatophyte infection is sometimes neglected. An observational study has been realized to evaluate the role of corticosteroid exposure (tinea incognito) and of other primary characteristics of the dermatophytosis that from onset mimic other diseases and mislead an unexperienced physician.
  
  
  METHODS
  Between 1990 and 2009, all cases of atypical dermatophytosis mimicking other skin diseases were collected from the more general number of dermatophyte infections diagnosed at the Dermatology Department of Cagliari University, Italy.
  
  
  RESULTS
  One-hundred and fifty-four cases (71 male/83 female, 2-81 years old) were studied, with a median of 7 cases/year. The most observed clinical forms were those mimicking impetigo, eczematous dermatitis, lupus erythematosus, polymorphous light eruption, psoriasis, and rosacea. The identified dermatophytes were: Microsporum canis (70 cases), Trichophyton rubrum (43 cases), Trichophyton mentagrophytes var. mentagrophytes (29 cases), Trichophyton mentagrophytes var. interdigitale (six cases), Microsporum gypseum (three cases), Epidermophyton floccosum (two cases), and Trichophyton verrucosum (one case). Diagnostic difficulties are discussed, with special attention to the origin of the pathomorphosis.
  
  
  CONCLUSIONS
  In our experience, clinical atypia is not a mere consequence of corticosteroid therapy but present at the very onset of the illness, due to the variable dermatophyte invasive capacity, the site of invasion, physiological individual, and/or acquired condition, such as excessive washing or sun exposure. Therefore, we suggest using the term "tinea atypica" rather than "tinea incognito" to include all forms of dermatophytosis that do not present the classic features for both primary and secondary pathomorphosis.
authors.affiliation: Dermatology Department, Cagliari University, Italy. laura.atzori@libero.it
authors.forename: Laura
authors.initials: L
authors.lastname: Atzori
authors.forename: Monica
authors.initials: M
authors.lastname: Pau
authors.forename: Natalia
authors.initials: N
authors.lastname: Aste
authors.forename: Nicola
authors.initials: N
authors.lastname: Aste
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000935:Antifungal Agents / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D004821:Epidermophyton; D005260:Female; D006801:Humans; D007558:Italy; D008297:Male; D008853:Microscopy; D008864:Microsporum; D008875:Middle Aged; D012189:Retrospective Studies; D012871:Skin Diseases / Q000175:diagnosis; D014005:Tinea / Q000175:diagnosis* / Q000188:drug therapy / Q000382:microbiology*; D014249:Trichophyton; D055815:Young Adult
chemical_list: D000935:Antifungal Agents