Malassezia folliculitis

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Malassezia folliculitis
Other names: Pityrosporum folliculitis
25-year-old man with pityrosporum folliculitis and electron micrograph of his skin, showing Malassezia spores.[citation needed]

Malassezia folliculitis or Pityrosporum folliculitis,[1] is a skin condition caused by infection by Malassezia (formerly Pityrosporum) yeast.[2]: 314 

The skin of the upper trunk area including the back, chest, arms and sometimes the neck is often affected and this condition is often seen in young to middle aged adults, although it has been known to occur in adults well into their sixties, and can also be found on the lower extremities as well. Its diagnosis is based on the pruritic (itchy) papulopustules found in a follicular pattern in these regions.[3]

Pustules are caused by an overgrowth of the yeast (a type of fungus) Malassezia furfur (Pityrosporum ovale), which plugs the follicles. M. furfur is lipophilic, requiring fatty acids like what is present in oily skin to proliferate. It has been shown that Malassezia yeast grows by consuming fatty acids with carbon chain lengths C11 to C24.[4] Pityrosporum is part of the normal skin flora, but overgrows in certain conditions.[3] Overgrowth is associated with oily skin, humidity or other pre-existing dermatologic conditions such as seborrheic dermatitis and severe dandruff.[5]

See also


  1. Rapini, Ronald P.; Bolognia, Jean L.; Jorizzo, Joseph L. (2007). Dermatology: 2-Volume Set. St. Louis: Mosby. ISBN 978-1-4160-2999-1.
  2. James, William D.; Berger, Timothy G.; et al. (2006). Andrews' Diseases of the Skin: clinical Dermatology. Saunders Elsevier. ISBN 0-7216-2921-0.
  3. 3.0 3.1 Siobahn M Bower, MD; Daniel J Hogan, MD & Stephen H Mason, MD (December 21, 2009). "Malassezia (Pityrosporum) Folliculitis". eMedicine by WebMD. Archived from the original on August 18, 2011. Retrieved January 30, 2009.
  4. Wilde, P. F.; Stewart, P. S. (December 1, 1968). "A study of the fatty acid metabolism of the yeast Pityrosporum ovale". Biochemical Journal. 108 (2): 225–231. doi:10.1042/bj1080225. PMC 1198797. PMID 5691082.
  5. American Osteopathic College of Dermatology. "Dermatologic Disease Database: Pityrosporum Folliculitis". Archived from the original on January 18, 2009. Retrieved January 30, 2009.