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""What causes tiny, veritcal lines under fingernails?""

ZocdocAnswers"What causes tiny, veritcal lines under fingernails?"


I'm a younger mom and I know I tend to be overprotective, but why would my son (6 years old) have tiny, vertical lines under some of his fingernails? It's not a big deal to me if this is just the result of his playing rough and banging up his hands? but if it could be something more serious, I definitely want to know now so I can have him seen by a doctor.


There are many causes to changes in the appearance of the nail. Fortunately most are not serious. If you wish to discuss this issue in further detail, your pediatrician would be able to discuss it. Fortunately, vertical lines on the nail are very rarely a sign of a serious underlying illness. Various forms of horizontal line, on the other hand, can at times represent an underlying illness. Verticle ridges or lines that run from the cuticle to the tip of the nail can be common. There is no clear cause of these deformations, although it is possible that they have a genetic component, and they do not require treatment. Small white spots or lines under the nail are called leuconychia. These are probably caused by trauma to the nail bed or air bubbles under then nail and they grow out as the nail grows out and require no treatment. Occasionally, a fungal infection of the nail can cause lines and ridges. Your pediatrician should be able to rule this possibility for you. If the lines are dark red, rarely the can be a sign of bleeding or a blood infection and should be investigated more closely. As always, the diagnosis and the management of your son's particular condition would require a physical examination by his personal physician. Scheduling an appointment with your pediatrician might be advisable.

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