Nailed It

As a child, I was a half-hearted stamp collector. When I went to medical school, learning the links between the heart and nails, I became a fanatical collector of somewhat obscure, but fascinating ways of diagnosing disease by examining the nails. I hope you enjoy this top twenty list of my favorites. 

As a child, I was a half-hearted stamp collector. When I went to medical school and learned the links between the heart and fingernails, I became a fanatical collector of somewhat obscure, but fascinating ways of diagnosing disease by examining the nails. I hope you enjoy this top twenty list of my favorites.

  1. As a pilot, you don’t want to chew your nails. Sometimes a bad habit carried over from childhood, it can be a sign of underlying anxiety disorders. Any passenger seeing their pilot with macerated nails, or worse still, seeing them gnawing away, will doubtless develop a medical condition of their own – profound stress!
  2. The expression to “hit the nail on the head” implies you have done something very well. However, if you literally hit your nail, rather than the metal one, you will learn about a physical reflex – the blow will cause you to speak unutterable phrases with gusto. The resulting bruise that forms under the nail, a subungual hematoma, can be exquisitely painful. Yes, apply ice and elevate the injured digit, but a rapid visit to your doctor can lead to an equally rapid cure – a paper clip opened up and heated until it glows can pop through the nail painlessly and release the trapped blood, leading to immediate resolution of your pain.
  3. Nails that are unduly brittle can suggest problems with several organs including kidneys and thyroid. Additionally, iron deficiency can cause this to develop.
  4. If your nails start splitting, consider whether you are getting sufficient protein, folic acid, and vitamin C in your diet.
  5. Notice that your nails are getting thicker? While this can be a natural sign of aging, it can hint at underlying problems with your circulation so will merit a trip to your doctor. As should any change you notice in your body!
  6. People with psoriasis, a condition afflicting the skin with red, scaly patches, can also develop an associated form of arthritis that tends to focus on small joints such as the fingers. Additionally, one may notice little pits appearing in the nails which can be a hint that problems are mounting.
  7. The nails can also change shape and sometimes will curve to give the impression of spooning – we call that koilonychias and this is indicative of an iron deficiency anemia.
  8. If you take a peek at your fingernails from the side, you will see that where the nail meets your cuticle, it dips down. This is called the paranychial angle and in certain diseases it magically disappears in a phenomenon we call clubbing – and this has nothing to do with nightlife, dance-floor gyrations, or intoxication. This can happen with liver problems, certain bowel diseases like Crohn’s, or anything causing poor oxygen levels in the blood such as lung cancer and bronchiectasis. If present on just one side of the body, that clues doctors in to the presence of a swelling or aneurysm in an artery underneath your collar bone.
  9. Changes in color of the nails is also indicative of disease. The most obvious is staining from cigarettes or henna, but yellowed nail beds indicate chronic bronchitis, lymphatic disease, diabetes, or some liver diseases.
  10. Brown nails suggest that one is accumulating copper (Wilsons disease) or arsenic is finding its way into your body. And that might mean someone has it in for you. Nailed on!
  11. Dark nails, on the other hand – or both hands – can suggest a deficiency of vitamin B12, and at this point I have to tell you the most useless fact I know; if you are stranded, cold, and hungry in the arctic and choose to shoot a polar bear, do not, under any circumstances, eat the liver as you will consume way too much B12. At least your nails won’t be dark!
  12. If your nail beds look blue that can indicate heart disease and merits a swift checkup. As an aviator, blue nail beds suggest you better apply that supplemental oxygen pronto!
  13. Dark streaks in the nails are called melanonychia and can reveal that there is a malignant melanoma tumor lurking underneath.
  14. Various marks can appear such as Aldrich-Mees lines, which are white bands across the nail and imply arsenic, thallium, or other heavy metal poisoning or kidney failure. This is also seen in people receiving chemotherapy for a cancer.
  15. However, Beaus lines are deep grooves across the nails and are probably just a sign of aging.
  16. We should also put the finger on Muehrckes lines, curved white lines that disappear with pressure on the nail. These are found in circumstances where someone has low protein states, kidney failure, severe hypertension, and also when receiving chemotherapy.
  17. Terrys nails are white, with a ground glass appearance and loss of the lunula, the curved pale area at the base of the nail. This is caused by decreased blood supply and increased connective tissue and is due to liver failure, diabetes, heart failure, hyperthyroidism, or in those who are malnourished.
  18. Lindsays’ or half-and-half nails are, as the name suggests, two colors. The area near the base is white and the ends are darker red or brown. This phenomenon occurs in kidney failure and also in those receiving dialysis.
  19. If you see tiny little spidery blood vessels around the nails, this is Braverman’s sign and indicates that one of the rather rare collagen vascular diseases is brewing.
  20. Tiny, elongated dark smudges in the nail bed are known as splinter hemorrhages and, especially if they appear shortly after dental treatment, physicians suspect infective endocarditis, where bacteria have gotten into the heart via the gums and caused little blood clots to travel around the body.

Hopefully I have given you some nice Trivial Pursuit answers and maybe you will do as I do and check out people’s nails. I recently heard from a good friend how disgusted she was to see a gentleman turn up at a fancy wedding with dirt under his nails; it led her to reach conclusions about this man, his attention to personal hygiene, and, in fact, his character. She was doing as I have suggested, viewing the nails as a way of characterizing what may be wrong with someone. And I think she nailed it.

Jonathan Sackier

Dr. Jonathan Sackier is an expert in aviation medical concerns and helps members with their needs through AOPA Pilot Protection Services.
Topics: Pilot Health and Medical Certification

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