If you see this line on your fingernail, see your doctor immediately: experts

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(NEXSTAR) – What started out as a “tiny little brown line” on one woman’s fingernail led to a rare, potentially life-threatening medical condition, one that she’s now trying to help others catch early.

Lauren Koltcz said she noticed the mark on her left thumb nail last May and thought to herself, “Well, that’s odd.”

While rare and easily missed, the “splinter”-like line shouldn’t be ignored, experts warn.

TikTok helps woman take action on fingernail line

“If you have a dark-pigmented vertical streak going down your nail, this should be checked,” Dr. Lindsey Zubritsky, a Mississippi-based dermatologist, warned her 1.6 million TikTok followers.

Koltcz mentioned it to her doctor, who referred her to a specialist.

“She recommended I go to the dermatologist, but being a mom and being a teacher, I put it on the back burner, and I just let it go,” Koltcz told the Cleveland Clinic.

What started as a tiny line on Lauren Koltcz’s thumbnail ended up being diagnosed as a case of melanoma. (Credit: Cleveland Clinic)

After nearly a year, Koltcz says TikTok, notorious for some of the unvetted advice on the platform, helped her take action.

“I happened to come across a dermatologist saying, ‘If you see these signs on your nails, make sure you go see your doctor very quickly.’ And I was like, ‘Oh, well, this doesn’t sound good.'”

Lab tests at the Cleveland Clinic confirm melanoma

Koltcz saw a dermatologist at the Cleveland Clinic, and lab tests confirmed that she had a melanoma. “Her biopsy showed what’s called a melanoma in situ, what that means is that the melanoma cells are just in the upper layer of the skin. It was not invasive, so her outcome should be very good,” said Dr. Allison Vidimos, a dermatologist at the Cleveland Clinic. 

Unlike other melanomas, Vidimos added that research suggests the one Kotcz had isn’t caused by sun exposure, and because symptoms can often be confused for other medical issues, it’s important to be evaluated by a dermatologist if you notice anything unusual.

Koltcz, whose entire left thumb nail was removed, said she’s now just happy to be healthy and is urging others to look out for themselves.

“I thought about my kids a lot during this whole process. And so, I beg people, please check everything. Don’t put it off. Prevention is key,” she said.

Health

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