Which diagnostic test can aid diagnosis of tinea versicolor apart from KOH scraping?

• A. Wood's lamp examination
• B. MRI
• C. Chest X-ray
• D. Complete blood count

Answer: (A)

Wood’s lamp examination uses ultraviolet light to reveal a characteristic fluorescence from the skin lesions caused by Malassezia furfur. The yeast metabolizes lipids on the skin and produces porphyrins that glow a yellow-orange (copper-orange) color under the UV light, helping to delineate the infected areas. This quick, noninvasive test complements KOH scraping by providing visual confirmation at the bedside and helps distinguish tinea versicolor from other causes of pale or pigmented patches, like vitiligo or pityriasis alba. Imaging studies or a CBC won’t detect superficial fungal infections, so they aren’t useful for this purpose.