Due to lots of misinformation about Vitiligo, people confuse any white spots on skin as Vitiligo. There can be lots of reasons for the white spots on skin including, but not limited to, Tinea Versicolor, fungal infection, Cutaneous (skin) porphyrias etc. A proper diagnostics by a certified dermatologist is essential to ensure that your skin condition is, in fact, Vitiligo and not something else.
Usually dermatologist uses Ultraviolet Light to identify Vitiligo. On examining the patient’s skin in ultraviolet light in a dark room, white spots caused by the Vitiligo provide a pearly appearance, as if they were a drop of milk. This aspect of the depigmented area or white stains to ultraviolet light is usually Vitiligo.
Another way to diagnose Vitiligo is biopsy. A sample of lesion is taken and tested for the absence of melanocytes and melanin in the basal layer of the epidermis. If results come positive, then the skin condition causing white spots is Vitiligo.
It is also advisable to perform a blood test to determine the concentration of thyroid hormones and glucose to rule out the existence of any other pathologies associated with Vitiligo.