Leukonychia (or leuconychia),
also known as white nails or milk spots, is a medical term for white
discoloration appearing on nails. It is derived from the Greek words leuko
("white") and onux ("nail"). The most common cause is
injury to the base of the nail (the matrix) where the nail is formed.
It is harmless and most commonly
caused by minor injuries that occur while the nail is growing. Contrary to
popular belief, leukonychia is not a sign of excess or deficiency of calcium
and zinc or other vitamins in the diet, but rather less commonly a medical sign
of hypoalbuminemia or chronic liver disease. It is more commonly found on
fingernails than toenails. There is no effective treatment for leukonychia.
However, the white marks and spots gradually disappear as the nail grows
outward from the matrix with the nail plate.
Types:
Leukonychia totalis: This condition is a whitening of the entire
nail. This may be a clinical sign of hypoalbuminaemia (low albumin), which can
be seen in nephrotic syndrome (a form of kidney failure), liver failure,
protein malabsorption and protein-losing enteropathies. A genetic condition,
and a side effect of sulphonamides, a family of antibiotics can also cause this
appearances.
Leukonychia partialis: This
condition is whitening of parts of the nail plate in form of small white dots.
There are several types of this condition. There are three variations of
partial leukonychia; punctate, transverse and longitudinal leukonychia. Some
more serious variations of leukonychia partialis may lead to Leukonychia
totalis.
Leukonychia striata: Leukonychia striata, transverse leukonychia,
or Mees' lines are a whitening or discoloration of the nail in bands or
"stria" that run parallel the lunula (nail base). This is commonly
caused by physical injury or disruption of the nail matrix. Common examples
include excessive tapping of the nails, slamming a car door or extensive use of
manicure. It may also occur in great toenails as a result of trauma from
footwear. Alternatively, the condition can be caused by heavy metal poisoning
most commonly by lead or arsenic. It can also be caused by cirrhosis or
chemotherapy. The tendency toward leukonychia striata is sometimes inherited in
an autosomal dominant fashion. In other cases, it can be attributed to vigorous
manicuring and trauma aforementioned, or to a wide variety of systemic
illnesses. Serious infections known for high fevers, measles, malaria, herpes,
and leprosy may also cause this condition. In many patients, there is no
obvious cause, and the streaks resolve spontaneously. There is a similar
condition called Muehrcke's lines (apparent leukonychia) which differs from
leukonychia in that the lines fade with digital compression and does not
migrate with the growth of the nail.
Leukonychia punctata: Also known as "true" leukonychia,
this is the most common form of leukonychia, in which small white spots appear
on the nails. Picking and biting of the nails are a prominent cause in young
children and nail biters. Besides parakeratosis, air that is trapped between
the cells may also cause this appearance. It is also caused by trauma. In most
cases, when white spots appear on a single or a couple of fingers or toes, the
most common cause is injury to the base (matrix) of the nail. When this is the
case, white spots disappear after around eight weeks, which is the amount of
time necessary for nails to regrow completely. The pattern and number of spots
may change as the nail grows.
Longitudinal
leukonychia: Longitudinal leukonychia is far less common and features
smaller 1mm white longitudinal lines visible under the nail plate. It may be
associated with Darier’s disease.
Diagnosis and treatment: A
doctor will take a thorough medical history, and may take blood tests as well
as examining liver and kidney function.
No comments:
Post a Comment