Yes! Skin discoloration can either be characterized as hyperpigmentation (dark patches) or hypopigmentation (light patches) and can be quite pronounced in Indian, Pakistani, and other South Asian and ethnic skin. The skin can look especially uneven and in the case of light patches, many patients become concerned about the possibility of vitiligo. However, the more common condition that produces skin discoloration is due to a yeast that lives on the skin normally and can become more active with heat and sweat. This results in the production of rough pink patches and skin discoloration (both light and dark patches). This condition is very benign and easily treated although it has a high recurrence rate over time.
This condition known as tinea versicolor (or pityriasis versicolor) is caused by malassezia, a yeast that commonly lives on the skin. This yeast is so common it is actually implicated in the production of scalp dandruff. In the case of tinea versicolor, the malassezia yeast that resides in the oilier areas of the skin such as the chest, shoulders, and back proliferates due to heat and sweating and becomes activated. It is believed that the malassezia produces patches of light skin by producing a substance known as azelaic acid which inactivates the pigment producing cells (melanocytes) of the skin. The result is patches of lighter skin. The rash itself can be pink or dark and can lead to additional dark patches due to post-inflammatory hyperpigmentation (especially in Indian, Pakistani, and other South Asian skin types) resulting in an overall pattern of scaly pink patches, light patches, and dark patches.
Tinea versicolor can occur in almost anybody but some people have a higher predisposition than others. Usually, the yeast will become active in the hotter and more humid seasons and in the setting of increases in activity and sweating. There is often a seasonal pattern with higher rates in the summer or at times when individuals pick up a more intense exercise regimen (i.e, around the New Year!).
Fortunately, treatment is effective and simple. Usually, the yeast can be cleared with a simple oral or topical antifungal medication and there are many different treatment regimens that can be used. Two points to bear in mind: 1. although the yeast can be cleared easily, the skin discoloration can take weeks and even months to even out and 2. there is a high rate of recurrence so it is best to take measures to minimize the yeast on the skin. Usually, a weekly application of an antifungal shampoo or selenium sulfide based shampoo is sufficient to minimize the risk of recurrence.
With a bit of vigilance and maintenance treatment, it is easy to clear this fungus among us!