White areas on fingernails can have various causes, ranging in severity from 'troubling' to 'generally fatal'. Finding the true cause means ruling out or confirming each possibility – in other words, diagnosis.
Diagnosis is usually a complex process due to the sheer number of possible causes and related symptoms. In order to diagnose white areas on fingernails, we could:
|Iron Deficiency Anemia||30%||Unlikely|
|Chronic Renal Insufficiency||16%||Unlikely|
|Cirrhosis Of The Liver||5%||Ruled out|
|Mercury Toxicity||1%||Ruled out|
|Nephrotic Syndrome||1%||Ruled out|
|Ulcerative Colitis||1%||Ruled out|
|Low Albumin||0%||Ruled out|
Do you have any white areas (not spots) on your fingernails that are not due to nail injury/trauma?
Possible responses:→ No / don't know
→ Pink at the base, turning white towards the ends
→ 80% or more of nail beds are white, including base
→ White lines from side to side, do not move
→ White lines from side to side, move as nails grow
Leukonychia (partial or completely white nails) is a sign of renal failure.
Mainly white nails, or Terry's Nails, are a significant indicator of hepatic cirrhosis. [Terry (1954) Lancet, 1:757]
Mees' Lines (transverse white lines) are a sign of arsenic poisoning.
Muehrcke's Lines (side-to-side parallel white lines that do not move with nail growth) are caused by a nail bed abnormality, which in turn is probably due to hypoalbuminemia.
Hypoalbuminemia (A low albumin level) also suggests the following possibilities:
All heavy metals cause Mees' lines on the nails. These usually begin a few months after significant exposure starts and may be useful in identifying the source of exposure – dental amalgams or some unrecognized source – if you remember when they started.