Beau's lines
Encyclopedia
Beau's lines are deep grooved lines that run from side to side on the fingernail
. They may look like indentations or ridges in the nail plate. This condition of the nail was named by a French physician, Joseph Honoré Simon Beau
(1806–1865), who first described it in 1846.
Beau's lines are horizontal, going across the nail, and should not be confused with vertical ridges going from the bottom (cuticle
) of the nail out to the fingertip. These vertical lines are usually a natural consequence of aging and are harmless. Beau's lines should also be distinguished from Muehrcke's lines
of the fingernails. While Beau's lines are actual ridges and indentations in the nail plate, Muehrcke lines are areas of hypopigmentation without palpable ridges; they affect the underlying nail bed not the nail itself.
There are several reasons that humans get Beau's lines. It is believed that there is a temporary cessation of cell division
in the nail matrix. This may be caused by an infection
or problem in the nail fold, where the nail begins to form, or it may be caused by an injury to that area. Some other reasons for these lines include trauma, coronary occlusion
, hypocalcaemia
, and skin disease. They may be a sign of systemic disease, or may also be caused by an illness of the body, such as diabetes, psoriasis
, certain drugs—including beta blocker
s according to the Cleveland Clinic
, as well as other drugs used in chemotherapy
—or even malnutrition
.
Human nails grow at a rate which varies with many factors age, sex and the finger or toe in question as well as nutrition. However, typically in healthy populations fingernails grow at about 0.1mm/day and toenails at about 0.05mm/day. With this in mind the date of the stress causing Beau's lines and other identifiable marks on nails can be estimated.
A researcher found Beau's lines in the fingernails of two of six divers following a deep saturation dive
to a pressure equal to 305 meters of sea water, and in six of six divers following a similar dive to 335 meters.
Beau's lines can also be seen one to two months after the onset of fever in children with Kawasaki disease
.
Nail (anatomy)
A nail is a horn-like envelope covering the dorsal aspect of the terminal phalanges of fingers and toes in humans, most non-human primates, and a few other mammals. Nails are similar to claws, which are found on numerous other animals....
. They may look like indentations or ridges in the nail plate. This condition of the nail was named by a French physician, Joseph Honoré Simon Beau
Joseph Honoré Simon Beau
Joseph Honoré Simon Beau was a French physician, who is famous for his investigations of the physiology of the heart and the lungs.-See also:* Beau's lines* Beau's syndrome...
(1806–1865), who first described it in 1846.
Beau's lines are horizontal, going across the nail, and should not be confused with vertical ridges going from the bottom (cuticle
Cuticle
A cuticle , or cuticula, is a term used for any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of "cuticles" are non-homologous; differing in their origin, structure, function, and chemical composition...
) of the nail out to the fingertip. These vertical lines are usually a natural consequence of aging and are harmless. Beau's lines should also be distinguished from Muehrcke's lines
Muehrcke's lines
Muehrcke's nails, Muehrcke's lines, or leukonychia striata, are changes in the fingernail that may be a sign of an underlying medical disorder or condition. Muehrcke's lines are white lines that extend all the way across the nail and lie parallel to the lunula . In contrast to Beau's lines, they...
of the fingernails. While Beau's lines are actual ridges and indentations in the nail plate, Muehrcke lines are areas of hypopigmentation without palpable ridges; they affect the underlying nail bed not the nail itself.
There are several reasons that humans get Beau's lines. It is believed that there is a temporary cessation of cell division
Cell division
Cell division is the process by which a parent cell divides into two or more daughter cells . Cell division is usually a small segment of a larger cell cycle. This type of cell division in eukaryotes is known as mitosis, and leaves the daughter cell capable of dividing again. The corresponding sort...
in the nail matrix. This may be caused by an infection
Infection
An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
or problem in the nail fold, where the nail begins to form, or it may be caused by an injury to that area. Some other reasons for these lines include trauma, coronary occlusion
Coronary occlusion
A coronary occlusion is the partial or complete obstruction of blood flow in a coronary artery. This condition may cause a heart attack.In some patients coronary occlusion causes only mild pain, tightness or vague discomfort which may be ignored: the myocardium is however damaged....
, hypocalcaemia
Hypocalcaemia
In medicine, hypocalcaemia is the presence of low serum calcium levels in the blood, usually taken as less than 2.1 mmol/L or 9 mg/dl or an ionized calcium level of less than 1.1 mmol/L or 4.5 mg/dL. It is a type of electrolyte disturbance...
, and skin disease. They may be a sign of systemic disease, or may also be caused by an illness of the body, such as diabetes, psoriasis
Psoriatic nails
Psoriatic nails is a nail disease. It is common in those suffering from psoriasis, with reported incidences varying from 10% to 78%. Elderly patients and those with psoriatic arthritis are more likely to have psoriatic nails.-Symptoms:...
, certain drugs—including beta blocker
Beta blocker
Beta blockers or beta-adrenergic blocking agents, beta-adrenergic antagonists, beta-adrenoreceptor antagonists or beta antagonists, are a class of drugs used for various indications. They are particularly for the management of cardiac arrhythmias, cardioprotection after myocardial infarction ,...
s according to the Cleveland Clinic
Cleveland Clinic
The Cleveland Clinic is a multispecialty academic medical center located in Cleveland, Ohio, United States. The Cleveland Clinic is currently regarded as one of the top 4 hospitals in the United States as rated by U.S. News & World Report...
, as well as other drugs used in chemotherapy
Chemotherapy
Chemotherapy is the treatment of cancer with an antineoplastic drug or with a combination of such drugs into a standardized treatment regimen....
—or even malnutrition
Malnutrition
Malnutrition is the condition that results from taking an unbalanced diet in which certain nutrients are lacking, in excess , or in the wrong proportions....
.
Human nails grow at a rate which varies with many factors age, sex and the finger or toe in question as well as nutrition. However, typically in healthy populations fingernails grow at about 0.1mm/day and toenails at about 0.05mm/day. With this in mind the date of the stress causing Beau's lines and other identifiable marks on nails can be estimated.
A researcher found Beau's lines in the fingernails of two of six divers following a deep saturation dive
Saturation diving
Saturation diving is a diving technique that allows divers to reduce the risk of decompression sickness when they work at great depth for long periods of time....
to a pressure equal to 305 meters of sea water, and in six of six divers following a similar dive to 335 meters.
Beau's lines can also be seen one to two months after the onset of fever in children with Kawasaki disease
Kawasaki disease
Kawasaki disease , also known as Kawasaki syndrome, lymph node syndrome and mucocutaneous lymph node syndrome, is an autoimmune disease in which the medium-sized blood vessels throughout the body become inflamed. It is largely seen in children under five years of age...
.