Medicine Central™ is a quick-consult mobile and web resource that includes diagnosis, treatment, medications, and follow-up information on over 700 diseases and disorders, providing fast answers—anytime, anywhere. Explore these free sample topics:
-- The first section of this topic is shown below --
- Rash due to a common superficial mycosis with a variety of colors and changing shades of color, predominantly present on trunk and proximal upper extremities; macules are usually hypopigmented, light brown, or salmon-colored; fine scale is often apparent. It is not a dermatophyte infection.
- System(s) affected: skin/exocrine
- Synonym(s): pityriasis versicolor
- Common, occurs worldwide, especially in tropical climates, where prevalence can reach 50%
- Predominant age: teenagers and young adults
- Predominant sex: male = female
Usually occurs after puberty (except in tropical areas); facial lesions are more common in children.
Not common in the geriatric population
Etiology and Pathophysiology
Inhibition of pigment synthesis in epidermal melanocytes, leading to hypomelanosis; in the hyperpigmented type, the melanosomes are large and heavily melanized (1).
- Saprophytic yeast: Pityrosporum orbiculare (also known as Plasmodium ovale, Malassezia furfur, or Malassezia ovalis), which is a known colonizer of all humans
- Development of clinical disease associated with transformation of Malassezia from yeast cells to pathogenic mycelial form likely multifactorial, due to host and/or external factors
- Not linked to poor hygiene
Genetic predisposition may exist.
- Hot, humid weather
- Use of topical skin oils
- HIV infection/immunosuppression
- High cortisol levels (Cushing, prolonged steroid administration)
- Oral contraceptives
- Recheck and use prophylaxis each spring prior to tanning season.
- Avoid skin oils.