• Nail abnormalities are a common sign of kidney disease.
• People with kidney disease can develop changes in the color, texture, shape, and strength of their nails.
• Nail changes can occur as a result of kidney disease complications and treatments.

Changes in your fingernail color, texture, or shape can tell you a lot about your overall health. If you’re living with a kidney disease, such as immunoglobulin A (IgA) nephropathy, complement 3 glomerulopathy (C3G), or another type of chronic kidney disease, you already know that these conditions can affect many parts of your body, including the skin and nails. Researchers have found that around 70 percent of people who are uremic (have waste products in the blood from kidney disease) have some type of nail disorder.

Continue reading to learn more about how your kidney health can affect your nails if you’re living with kidney disease.

What Are Nails?

Your nails are the hard appendages at the ends of your fingers and toes. Your fingernails and toenails are actually made of skin cells. A protein called keratin helps harden your nails to protect the ends of your fingers and toes.

The hard, curved portion that we usually call a nail is technically called the nail plate. The nail plate is attached to the skin beneath it, called the nail bed. The lunula is a white, half-moon-shaped area at the bottom of your nail where nail growth occurs.

Your nails grow slowly — about one-tenth of an inch every month. This means it can take between three and six months to replace a nail completely. Your toenails grow a bit slower, so it can take even longer for a toenail to be fully replaced.

Your nail health can be affected by many different medical conditions and treatments, including:

• Infections, such as fungal infections and warts
• Chronic (long-term) medical conditions, including kidney, lung, heart, and liver diseases
• Vitamin and mineral deficiency, such as vitamin C, B vitamins, and iron deficiency
• Cancer, such as skin cancer
• Medications, including chemotherapy and certain antibiotics

How Can Kidney Disease Affect Your Nails?

Your kidneys can affect many parts of your body, including your nails.

Some nail abnormalities are related to kidneys not working as well as they should. Your kidneys are responsible for filtering waste from your body, such as urea (nitrogen waste) and creatinine (creatine waste). If your kidney function is low, waste levels in your body can build up and make you sick. These waste products can also affect your nails.

Complications of kidney disease that may cause or worsen nail problems include:

• Anemia (lower-than-normal red blood cell count)
• Problems regulating calcium
• Poor nutrition, which can increase the chance of infections
• Heart disease
• Damage to the nerves

Nail changes are also associated with some treatments for kidney disease, such as hemodialysis (dialysis). Researchers have found that 3 out of every 4 people receiving hemodialysis experience nail changes.

You may not notice changes right away. If you have kidney disease, it may be several years before your disease progresses to kidney failure. For example, many people with IgA nephropathy or C3G can live with kidney disease for 10 to 15 years before progressing to kidney failure.

What Changes Might You See in Your Nails With Kidney Disease?

Kidney disease can cause changes in the color, texture, strength, and shape of your nails. Examples of some nail disorders that are more common in people with kidney problems are discussed below. While these nail disorders are often associated with kidney disease, other medical conditions can also cause these nail problems.

Half-and-Half Nails

If you have half-and-half nails — also called Lindsays’ nails — the bottom halves of them (closest to your knuckles) appear white. The top halves (closest to your fingertips) are discolored in a pink, red, or brown color. The lunula may not be visible with the white band at the bottom of an affected nail. In a 2019 study in the Journal of Dermatology Research and Therapy of 70 people with end-stage kidney disease, researchers found that about half of all participants had nail changes that include the absence of a lunula.

For most people, the white bands and darker bands don’t change as the nail grows. These changes can affect just one finger or toe or all of them.

Researchers aren’t sure why people with kidney disease can develop half-and-half nails. The white bands at the bottom may be related to anemia. The darker bands at the top could be related to increased production of the skin pigment called melanin. Melanin production can be increased when urea levels in the blood increase.

The appearance of half-and-half nails isn’t associated with the severity of kidney disease. This means you may develop this nail condition even if you have mild kidney impairment. Additionally, it may not improve with treatments such as dialysis or kidney transplant.

The development of half-and-half nails can also occur in people with other medical conditions or people without chronic medical conditions.

Detached Nails

It’s possible for part of a nail to become detached in someone living with kidney disease. This is called onycholysis. When the nail plate becomes separated from the nail bed, it looks like areas of opaque white discoloration on the nail.

Onycholysis is a common nail condition for people with kidney disease, especially in the setting of kidney failure. The 2019 study found that more than 70 percent of participants with end-stage kidney disease had onycholysis.

Medical conditions associated with kidney disease that can also cause onycholysis include:

• Skin diseases, such as psoriasis
• Fungal infections
• Diabetes
• Sarcoidosis (an autoimmune disorder)

Other possible causes of onycholysis include trauma (e.g., manicures or immersion in water for extended periods of time), pregnancy, hormone disorders, and medications, such as some antibiotics.

White Nails

Some people with kidney disease may notice that their nails become pale or white in color — called leukonychia. Leukonychia is the most common nail disorder in people who have received a kidney transplant.

Three different types of leukonychia may be associated with kidney disease:

• Muehrcke’s lines — Horizontal white lines across the nail
• Terry’s nails — When most of the nail bed appears white with a thin band of darker color at the top
• Half-and-half nails — When the bottom half of the nail appears white and the top half of the nail appears darker red or brown

Splinter Hemorrhages

Splinter hemorrhages can occur in people with chronic kidney disease, after a kidney transplant, or being treated with hemodialysis. A splinter hemorrhage looks like a splinter is stuck under your nail. Splinter hemorrhages can appear as red or purple lines under your nails.

You may develop a splinter hemorrhage if the capillaries (small blood vessels) under your nail become fragile, which is common in kidney disease. Splinter hemorrhages are most often caused by trauma but can also be caused by other conditions that affect blood vessels, such as:

• Infections
• Autoimmune conditions, including psoriasis and systemic lupus erythematosus (SLE), the most common form of lupus
• Raynaud’s disease, which causes spasms in the blood vessels of the hands and feet

Ridged Nails

Some people with kidney disease can develop abnormal ridges in their nails. A ridge can run horizontally or vertically in your nail. While nail ridges can be normal in some people, they can also be a sign of some medical conditions, such as kidney disease.

Beau’s lines are a common type of ridged nail that can occur in people with kidney disease. They appear as horizontal dents in your nail. You may develop a Beau’s line if nail growth stops and then restarts. Your nail growth may be interrupted by illness (such as acute kidney failure) or from poor nutrition related to kidney disease.

Usually, this type of ridge will grow out with time. The 2019 study found that about 36 percent of people with end-stage kidney disease had horizontal ridges in their nails.

Spoon-Shaped Nails

Spoon-shaped nails — also known as koilonychia — may develop in people with kidney disease. People with koilonychia have soft nails that grow in a dented spoon shape instead of growing straight. The spoon shape usually develops gradually over time.

The most common cause of koilonychia is iron-deficiency anemia. Anemia is common in people with chronic kidney disease — about 1 in 7 people with the condition.

Taking Care of Your Nails

Your nails can reveal important clues to the health of your body as a whole. Nail changes can occur even if your kidney disease is mild and well treated. If you’re living with kidney disease, it’s important to watch for nail changes and talk to your health care team as soon as you notice anything abnormal.

Talk to your health care team about a treatment plan that includes proper nail care and nutrition.

Talk With Others Who Understand

On MyKidneyDiseaseCenter, the site for people with kidney disease and their loved ones, people come together to gain a new understanding of different types of kidney disease and share their stories with others who understand life with kidney disease.

Have you noticed any changes in your nails? Share your experience in the comments below.