A 61-year-old man presents to the office seeking treatment for an extensive rash on his chest and back that was noted several weeks ago and has been rapidly progressing. He complains of mild, intermittent pruritus. Medical history is significant for hypertension, which was recently diagnosed and for which he has been taking chlorthalidone. Examination revealed both noncontiguous and confluent reddish macules and patches. Also noted on his back is a 2.5-cm nodule. On questioning, he reports that the lesion has been present for approximately 2 years.
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Tinea versicolor is a common superficial fungal infection with a predilection for the trunk, back, neck, and upper arms. Lesions vary in coloration from brown to red and may be discrete or confluent. Fine scale is often apparent. The disorder is caused by lipophilic yeast of the genus Malassezia.1 These organisms are a ubiquitous component of the normal skin flora and are found in greatest abundance at sites of increased sebaceous activity. Factors such as heredity, humid environment, and immunosuppression may play a role in predisposition to clinically apparent disease.2
Epidermoid cysts are most commonly found on the back and chest but can arise on virtually any part of the body. Epidermoid cysts are invaginations of the skin characterized by the accumulation of cellular debris and keratin within an epithelial-lined sack. A characteristic of epidermoid cysts is a visible punctum that denotes the orifice of an obstructed hair follicle from which the cyst originates. Trauma, aberrant embryogenesis, and inflammation of the pilosebaceous unit followed by dermal reaction are postulated etiologies. 3
Dr Schleicher is director of the DermDox Center for Dermatology, as well as an associate professor of medicine at Commonwealth Medical College and a clinical instructor of dermatology at Arcadia University and Kings College.
- Faergemann J, Fredriksson T. Tinea versicolor: some new aspects on etiology, pathogenesis, and treatment. Int J Dermatol. 1982;21:8-11.
- Klenk A, Martin A, Heffernan M. Yeast infections. Candidiasis pityriasis (tinea) versicolor. In: Freedberg I (ed.) Fitzpatrick’s Dermatology in General Medicine. Vol 2. New York: McGraw-Hill; 2003:2016-2018.
- Mayer JE, Miller MD, Birlea SA. Symmetric multilocular epidermoid cysts on the face: an unusual presentation of a common lesion. JAAD Case Reports. 2018;4(4): 337-339.