Tinea incognita
 | This article needs additional citations for verification. (December 2008) |
| Tinea incognita | |
|---|---|
| Other names | Tinea atypia[1] |
 | |
| Tinea incognita in the forearm of a child being treated for contact dermatitis | |
| Specialty | Dermatology |
Tinea incognita, also spelled tinea incognito, is a fungal infection of the skin that generally looks odd for a typical tinea infection.[1][2][a] The border of the skin lesion is usually blurred and it appears to have florid growth.[1]
It generally occurs following the application of a steroid cream to what at first is thought to be eczema.[1] Continued application results in expansion of the fungal infection which appears unrecognisable.[3] Occasionally, secondary infection with bacteria occurs with concurrent pustules and impetigo.[5]
Cause
[edit]The use of a topical steroid is the most common cause. Frequently, a combination topical steroid and antifungal cream is prescribed by a physician. These combinations include betamethasone dipropionate and clotrimazole (trade name Lotrisone) and triamcinolone acetonide and clotrimazole. In areas of open skin, these combinations are acceptable in treating fungal infection of the skin. In areas where the skin is occluded (groin, buttock crease, armpit), the immunosuppression by the topical steroid might be significant enough to cause tinea incognita to occur even in the presence of an effective antifungal.
Diagnosis
[edit]Clinical suspicion arises especially if the eruption is on the face, ankle, legs, or groin. A history of topical steroid or immunosuppressive agent is noted. Confirmation is with a skin scraping and either fungal culture or microscopic exam with potassium hydroxide solution. Characteristic hyphae are seen running through the squamous epithelial cells.
Treatment
[edit]The removal of the offending topical steroid or immunosuppressive agent and treatment with a topical antifungal is often adequate. If the tinea incognita is extensive or involves hair bearing areas, treatment with a systemic antifungal may be indicated.[citation needed]
Notes
[edit]References
[edit]- ^ a b c d Chander, Jagdish (2018). Textbook of Medical Mycology (4th ed.). New Delhi: Jaypee Brothers Medical Publishers Ltd. p. 172. ISBN 978-93-86261-83-0.
- ^ James, William D.; Elston, Dirk; Treat, James R.; Rosenbach, Misha A.; Neuhaus, Isaac (2020). "15. Diseases resulting from fungi and yeasts". Andrews' Diseases of the Skin: Clinical Dermatology (13th ed.). Elsevier. p. 296. ISBN 978-0-323-54753-6.
- ^ a b "What is tinea incognita?". DermNet NZ.
- ^ Verma, SB (March 2017). "A Closer Look at the Term "Tinea Incognito:" A Factual as Well as Grammatical Inaccuracy". Indian Journal of Dermatology. 62 (2): 219–220. doi:10.4103/ijd.IJD_84_17. PMC 5363154. PMID 28400650.
- ^ Habif, T. P. (1995) Clinical Dermatology. Mosby, 3rd ed.; pp. 41-42.