The Doctor Is In

Dr Max Pemberton

Q: I’ve noticed narrow white lines appearing on my nails. They only appear on my thumb, and are worse on the left one. Aside from this my nails seem fine. Any idea what these are? Or how to reduce them? - Bill

A: Dear Bill, you might be surprised to hear that one of the first things you are taught at medical school is to look at a patient’s nails. This is because while a change in colour, texture or shape can be harmless, it can also be a sign of disease. A lot of medical conditions involve changes to the nails in one way or another. Psoriasis, for example, can cause yellowishorange spots, called salmon patch dyschromia or “oily drop” sign. A nail that lifts up (the medical term is onycholysis) can be a sign of fungal infection. Pits in the nail can be a sign of certain types of arthritis. Spoon shaped nails (called koilonychia) can mean someone has a problem with their stomach or intestines, or sensitivity to gluten (coeliac disease). Yellow nails can be a sign of lung disease, as can bulbous shaped nails (called clubbing). Red lines, called splinter haemorrhages, can be a sign of kidney disease. The list of “nail signs”, as they are called, goes on and on. The problem is that they’re often not very specific—they can indicate a number of conditions so you can’t make a diagnosis from the nail alone. It does, however, sometimes help combined with other symptoms. So in general, it’s always worth showing nail changes to your GP. In your case, I suspect you have “Beau lines”. These are lines or grooves that run the width of the nail. It means that something temporarily stopped or slowed your nails while they were growing. As this part of the under-grown nail grows, we notice it, as it moves out of the nail bed and on to the exposed nail we can see. A lot of things can cause these—fever, pneumonia, problems with circulation, or chemotherapy, but so can simple, local injury to the nail bed, which we’re often not even aware has occurred (or we forget about because of the time it takes for the nail to grow). It’s worth showing them to a GP who can reassure you.

■

Got a health question for our resident doctor?

Email it confidentially to askdrmax@readersdigest.co.uk