Did you know that your fingernails can provide clues to your overall health?
You will see that with many of the nails pictured below share a common trait, vitamin/mineral deficiency of some sort. This is usually linked to either poor nutrition choices or a poor digestive system.
If you would like more information or would like me to perform a quick, noninvasive assessment of your nails please contact me.
Clubbed Fingernails
Clubbing involves a softening of the nail bed with the loss of normal Lovibond angle between the nail bed and the fold, an increase in the nail fold convexity, and a thickening of the end of the finger so it resembles a drumstick.
To determine whether nails are clubbed, have the patient place both forefinger nails together and look between them. If you can see a small diamond space between them (Schamroth's window) then the nails are not clubbed (Schamroth's sign). Causes of clubbing (not exhaustive) include the following:
- Pulmonary and cardiovascular causes (80%)
- Lung cancer, pulmonic abscess, interstitial pulmonary fibrosis, sarcoidosis, beryllium poisoning, pulmonary arteriovenous fistula, subacute bacterial endocarditis, infected arterial grafts, aortic aneurysm
- Gastrointestinal causes - Inflammatory bowel disease, sprue, neoplasms (esophagus, liver, bowel) (about 5%)
- Hyperthyroidism (about 1%)
Note: Chronic obstructive pulmonary disease does not cause clubbing.
Koilonychia
Koilonychia/spoon-shaped concave nails. This occurs normally in children and usually resolves with aging. To determine whether a nail is spooned, perform the water drop test. Place a drop of water on the nail. If the drop does not slide off, then the nail is flattened from early spooning. An experienced clinician can look at the nail and perform a "mental" water drop test. Causes include the following:
- Iron deficiency;
- Chronic malabsorption -Gastrointestinal causes - Inflammatory bowel disease
- Diabetes mellitus;
- Protein deficiency, especially in sulfur-containing amino acids (cysteine or methionine);
- Exposure to petroleum-based solvents;
- Systemic lupus erythematosus; and
- Raynaud's disease.
In 1846, Joseph Honor Simon Beau described transverse lines in the substance of the nail as signs of previous acute illness. The lines look as if a little furrow had been plowed across the nail. Illnesses producing Beau's lines include the following:
- Severe infection;
- Myocardial infarction;
- Hypotension, shock;
- Hypocalcemia; and Surgery.
Intermittent doses of immunosuppressive therapy or chemotherapy can also produce Beau's lines. Severe zinc deficiency has also been proposed as a cause of Beau's lines. By noting its location on the nail, the approximate date of the illness associated with it can be determined. Moreover, the depth of the line provides a clue to the severity of the illness.
Thin Brittle Nails
Thin, brittle nails can indicate the following:
- Metabolic bone disease (nail thinness is correlated with osteopenia);
- Thyroid disorder;
- Systemic amyloidosis (indicated by yellow waxy flaking); and
- Severe malnutrition or
- Chronic malabsorption -Gastrointestinal causes - Inflammatory bowel disease
Onychorrhexis
Onychorrhexis is the presence of longitudinal striations or ridges. It can simply be a sign of advanced age but it can also occur with the following:
- Rheumatoid arthritis;
- Peripheral vascular disease;
- Lichen planus; and
- Darier's disease (striations are red/white).
Central ridges can be caused by
- Chronic malabsorption -Gastrointestinal causes - Inflammatory bowel disease
- Iron deficiency;
- Folic acid deficiency; and
- Protein deficiency.
Central Nail Canal (Median Nail Dystrophy)
When a central nail canal is present, the cuticle is usually normal. Central nail canal is associated with:
Severe arterial disease ("Heller's fir tree deformity" -- a central canal with a fir tree appearance -- may occur with peripheral artery disease);
Severe malnutrition; and Repetitive trauma.
Nail Pitting
Nail pitting -- small punctate depressions -- are caused by nail matrix inflammation, which can be the result of:
- Psoriasis (random appearance of pits;
- Alopecia areata (geometric rippled grid);
- Eczema; and
- Lichen planus.
Nail Beading
With nail beading, the beads seem to drip down the nail like wax. It is associated with endocrine conditions, including the following:
- Diabetes mellitus;
- Thyroid disorders;
- Addison's disease; and
- Vitamin B deficiency
- Chronic malabsorption -Gastrointestinal causes - Inflammatory bowel disease
Rough Nail Surface
When nails look sandpapered and dull, consider:
- Autoimmune disease;
- Chronic malabsorption -Gastrointestinal causes - Inflammatory bowel disease
- Psoriasis;
- Chemical exposure; and
- Lichen planus.
Nail Thickening
Slow nail growth produces thickness. In such cases, the following should be considered:
- Onychomycosis;
- Chronic eczema;
- Peripheral vascular disease;
- Yellow nail syndrome; and Psoriasis.
Onycholysis
Onycholysis is distal separation of the nail plate from the underlying nail bed. It is associated with the following:
- Thyrotoxicosis;
- Psoriasis;
- Trauma;
- Contact dermatitis;
- Tetracycline;
- Eczema;
- Toxic exposures (solvents);
- Blistering from autoimmune disease; and Porphyria cutanea tarda (onycholysis and skin blistering from sun exposure)
- Chronic malabsorption -Gastrointestinal causes - Inflammatory bowel disease
Severe Nail Curvature (Beaked Nails)
Curved or beaked nails are caused by resorption of distal digit. Consider the following:
- Hyperparathyroidism
- Renal failure
- Psoriasis
- Systemic sclerosis
Complete Nail Destruction
Complete local nail destruction can be caused by local mechanisms, including trauma and paronychia. Generalized conditions that might cause complete nail destruction include the following:
- Toxic epidermal necrolysis;
- Chemotherapy;
- Bullous diseases; and Vasculitis
If you would like more information or would like me to perform a quick, noninvasive assessment of your nails please contact me.