Deformities, Dystrophies, and Discoloration of the Nails

Iron deficiency Iron Deficiency Iron deficiency is a common cause of anemia, a condition in which the number of red blood cells is low. Iron deficiency usually results from loss of blood in adults (including bleeding from... read more may cause spoon-shaped nails (koilonychia). This deformity is particularly characteristic of Plummer-Vinson syndrome Esophageal Webs Esophageal webs are thin membranes that grow across the inside of the upper part of the esophagus and may cause difficulty swallowing (dysphagia). (See also Overview of Esophageal Obstructions... read more .

Kidney failure Overview of Kidney Failure Kidney failure is the inability of the kidneys to adequately filter metabolic waste products from the blood. Kidney failure has many possible causes. Some lead to a rapid decline in kidney function... read more may cause the bottom half of the nails to turn white and the top half of the nails to turn pink or appear pigmented (half-and-half nails or Lindsay nails). This dystrophy can also occur in healthy people.

Cirrhosis Cirrhosis of the Liver Cirrhosis is the widespread distortion of the liver's internal structure that occurs when a large amount of normal liver tissue is permanently replaced with nonfunctioning scar tissue. The scar... read more may cause the nails to turn white, although the very top part of the nails may remain pinker. Intensely white nails, also called Terry nails, can be present not only in people with cirrhosis but also in those with chronic heart failure or diabetes. Low blood levels of the protein albumin (which may occur in people with cirrhosis) can cause horizontal white lines to form on the nails. Terry nails may sometimes occur as part of normal aging.

Some lung diseases, often accompanied by lymphedema Lymphedema Lymphedema is the accumulation of lymph in tissues, resulting in swelling. When lymphatic vessels are injured or obstructed, lymph fluid cannot drain and accumulates in tissues, causing swelling... read more (an accumulation of lymphatic fluid in tissues), may cause yellow nail syndrome, in which nails become thick, overcurved, and yellow or yellow-green in color.

Beau lines are horizontal grooves in the nail that occur when there is temporary slowing of growth of the nail. Sometimes the grooves can go all the way through the nail, leading to complete loss of the nail. They can occur after an infection, injury, systemic illness, or chemotherapy.

White horizontal lines across part of the nail (leukonychia) may appear after an injury. However, lines that run horizontally all of the way across the nail (Mees lines) may be associated with more serious health problems, including cancer or heart failure, chemotherapy, or exposure to certain toxins, such as arsenic, thallium, or other heavy metals. The nails can grow out normally if exposure to these toxins or chemotherapy is stopped.

In psoriasis Psoriasis Psoriasis is a chronic, recurring disease that causes one or more raised, red patches that have silvery scales and a distinct border between the patch and normal skin. A problem with the immune... read more , nails may have irregular pits (tiny depressions in the surface of the nail), oil spots (yellow-brown spots under the nail), separation of the nail plate from its bed (onycholysis), and thickening and crumbling of the nail plate.

Lichen planus Lichen Planus Lichen planus, a recurring itchy disease, starts as a rash of small, separate, red or purple bumps that then combine and become rough, scaly patches. The cause is unknown but may be a reaction... read more of the nail matrix causes scarring with early nail ridging and splitting, later leading to scarring and pterygium formation. Pterygium of the nail, which is caused by lichen planus, is scarring from the base of the nail outward in a V formation, which leads to loss of the nail.

People with alopecia areata Alopecia Areata Alopecia areata is sudden loss of patches of hair when there is no obvious cause such as a skin or general internal disorder. (See also Overview of Hair Growth and Hair Loss [Alopecia].) Alopecia... read more , a disorder in which round, irregular patches of hair are suddenly lost, may have nail pits that form a geometric pattern.

People who have alopecia areata, lichen planus, atopic dermatitis Atopic Dermatitis (Eczema) Atopic dermatitis (commonly referred to as eczema) is chronic, itchy inflammation of the upper layers of the skin that often develops in people who have hay fever or asthma and in people who... read more , or psoriasis may develop trachyonychia (rough, opaque nails that have ridges and a sandpaper-like appearance). Trachyonychia most frequently occurs in children.

Chemotherapy drugs may cause a darkening (hyperpigmentation) of the nail plate. Horizontal pigmented or white bands may also be seen in people treated with certain chemotherapy drugs.

Chloroquine, a drug used in the treatment of parasitic infections and certain types of autoimmune diseases, can cause the nail bed to turn blue-black.

Silver, which can be absorbed after occupational exposure or through taking dietary supplements containing colloidal silver protein, can cause the nails to turn a dark blue-gray.

Drugs that contain gold, which is rarely used in the treatment of rheumatoid arthritis, can turn nails light or dark brown.

Tetracycline antibiotics, ketoconazole, sulfonamide antibiotics, phenindione, and phenothiazines can cause blue or brown discoloration.

Zidovudine (ZDV), a drug used to treat human immunodeficiency virus (HIV) infection Human Immunodeficiency Virus (HIV) Infection Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and is treated with antiretroviral medications. If untreated, it can cause... read more , may cause brown-black longitudinal streaks. However, these streaks can also be present in people who have AIDS but are not receiving ZDV.

Arsenic poisoning can cause horizontal white lines to form on the nails or cause the nails to turn brown.

An injury (such as in prolonged hiking or skiing with poorly fitted footwear)

Overzealous nail cleaning

Psoriasis Psoriasis Psoriasis is a chronic, recurring disease that causes one or more raised, red patches that have silvery scales and a distinct border between the patch and normal skin. A problem with the immune... read more and thyrotoxicosis Hyperthyroidism Hyperthyroidism is overactivity of the thyroid gland that leads to high levels of thyroid hormones and speeding up of vital body functions. Graves disease is the most common cause of hyperthyroidism... read more

Frequent exposure to water, citrus fruits, and certain chemicals (such as those in cleaning agents)

Treatment with doxorubicin, captopril, practolol, 5-fluorouracil, and retinoids

Onychomycosis Onychomycosis Onychomycosis is a fungal infection of the nails. (See also Overview of Nail Disorders.) About 10% of people have onychomycosis, which most often affects the toenails rather than the fingernails... read more