A patch of skin has turned pale in one spot: vitiligo or tinea versicolor?

Finding one area where the color has drained out usually sends people straight to the word vitiligo. In practice, a fair share of those patches turn out to be tinea versicolor, where a yeast living on the surface of the skin is involved.

The two get confused because the visible result looks similar. Both show up as patches lighter than the skin around them, and both grow more obvious over summer once the surrounding skin tans. What differs is the reason the color left. In one case the cells that make pigment are gone from that area. In the other the pigment cells are still there, and something sitting in the surface layer is interfering with the pigment reaching the skin above.

This guide walks through what gets checked first on a pale patch, where the two conditions separate, and what to have ready before a consultation so the checking goes faster.

This article summarizes treatment information from BeautyStone Clinic in Hongdae, Seoul. Individual results vary, and whether a procedure suits you is a decision to make with a board-certified dermatologist.

What Gets Checked First on a Patch That Has Lost Color

What Gets Checked First on a Patch That Has Lost Color

The first thing anyone looks at is the border. Whether it drops off sharply, as though cut, or fades gradually into the skin around it changes what gets checked next. Alongside that comes the surface texture, because whether a light scratch raises a fine scale is a meaningful clue on its own.

To see both of those more clearly, a Wood's lamp* comes out. A reference on Wood lamp examination describes a mercury arc covered by a Wood filter, which allows a narrow range of light to escape at 320 to 400 nm, under which vitiligo patches fluoresce bright blue-white owing to the increased amount of dermal collagen illuminated. The same reference records tinea versicolor, caused by Malassezia furfur, as yellowish-white or copper-orange.

Wood's lamp: a device that shines a specific wavelength of ultraviolet light to exaggerate differences in skin color. It only reads clearly in a fully darkened room.

That reference is equally specific about preparation. It advises working in a completely dark environment with the lights off and the shades drawn, letting the lamp warm up for about a minute first, and warns that lint, topical medications and soap residue all fluoresce and create false positives. That is why it helps to arrive with nothing applied to the area.

What Gets Checked First on a Patch That Has Lost Color

Where Vitiligo and Tinea Versicolor Separate

Where Vitiligo and Tinea Versicolor Separate

The sharpest dividing line is whether fungal elements show up. In tinea versicolor, a light scrape of the surface scale examined under a microscope* shows short hyphae alongside round spores. A study comparing diagnostic methods for the condition concluded that KOH mount is the most sensitive modality in the diagnosis of pityriasis versicolor as compared to Wood's lamp, fungal culture and dermoscopy.

Microscope examination: a small amount of surface scale is scraped off and viewed under magnification to see whether fungal elements are present.

In that same study, 66.1 percent of patients showed fluorescent lesions under the Wood's lamp, and of 115 KOH-positive cases only 44.3 percent grew anything on fungal culture. Dermoscopy picked up scaling in 88.7 percent. Those numbers are the reason no single test gets treated as the final word.

There are also documented situations where the two overlap. A case report of tinea versicolor presenting as vitiligo records that examination with Wood's light revealed accentuated hypopigmentation of the surrounding healthy skin, creating an appearance similar to vitiligo. In that case a tape test performed twice on the affected areas came back positive for fungal elements, which settled the direction.

Why BeautyStone Clinic Works Through Pale Patches in Order

Why BeautyStone Clinic Works Through Pale Patches in Order

At BeautyStone Clinic in Hongdae, Seoul, a patch that has lost color doesn't get a name attached to it first. What is checkable gets checked in sequence: the border and surface texture by eye, then the Wood's lamp to widen the contrast, then a microscope if any scale can be lifted. The case above is exactly why, since appearance alone can send the assessment in the wrong direction.

So the consultation opens by asking when it first appeared, whether it has widened since, and whether it stands out more in summer or winter. Anything applied to that area gets covered in the same breath. If something has been going on the skin, it changes what the tests will show, which is also where the timing of the examination gets decided.

Why BeautyStone Clinic Works Through Pale Patches in Order

What Order the Checking and Care Usually Follow

What Order the Checking and Care Usually Follow

The first step is ruling the yeast in or out. Tinea versicolor is comparatively quick to confirm, and settling that narrows what's left. Since the scrape is the most sensitive method reported, it comes first whenever fine scale can be raised from the surface.

Next comes agreeing in advance that the color will not return the moment the result is in. A review of treatments for the condition reports that 53 percent of people adequately treated had one to four recurrences, whereas 14.7 percent had more than four relapsing episodes in one year, and distressing hypopigmentation may persist for months or years in 28 to 47 percent of cases. The same review judges whether treatment has worked by the disappearance of short hyphae on microscopic examination rather than by the color.

That distinction comes up constantly in practice. When the yeast is gone but the pale mark isn't, it is easy to read that as treatment failure. Knowing that the color takes its own time to match the skin around it prevents the reflex of applying the same product for longer and longer.

Last is setting a checking interval with recurrence in mind. Given the numbers above, relapse isn't rare, so deciding upfront when to look again means not starting from scratch if the patch fades a second time.

What to Bring to a Consultation

What to Bring to a Consultation

The most useful thing is a record of time. When it was first noticed, whether it has spread or held still, and whether the contrast shifts with the season all change the order of checking. Any photograph taken earlier is the most precise version of that record.

Whatever has been used on the area matters too. Ointments, creams, sunscreen, body wash, anything changed recently is worth mentioning. As above, residue that fluoresces under the lamp can make a finding appear where there isn't one. On the day of the examination, it helps to arrive with the area washed and nothing applied.

Finally, it helps to set expectations early. Identifying the cause and restoring the color do not move at the same speed. Separating the stage of finding out what it is from the stage of the color evening out keeps the plan from wobbling partway through.