Renal or kidney disease can impact how your fingernails and toenails look. The way they change can also indicate the severity of kidney disease.
Your nails can develop concave or spoon-shaped dents if you have kidney disease. They may have a yellow overcoat or an unnatural white and red-brown coloration that divides the nail in half. Plus, they can become brittle or detach from the skin, which can signify chronic renal failure. Find out more about nails and kidney disease below.
- White Streaks (Muehrcke’s Nails)
If you’re diagnosed with renal disease, you may notice a white streak or pale band forming horizontally across your nail plate. This is referred to as Muehrcke’s nails1 or line, named after Robert C. Muehrcke, the physician who described the condition.
Muehrcke’s nails occur when blood flow is restricted in the nailbed. A single line may not be necessarily alarming, but if you spot multiple streaks, consult with your doctor immediately.
These white lines could imply hypoalbuminemia (low blood albumin), a common end-stage renal disease symptom. To confirm the condition, you may need to take an albumin blood test.
Pale bands on the nail plate showing Muehrcke’s nails (Source: Wikimedia Commons)
- Concave Nails (Spoon-shaped Dent)
A concave nail (spoon nail) appears scooped out due to the nails’ softening. The condition is clinically known as koilonychia. The abnormal curvature is often due to iron deficiency, which can be common among those with kidney disease.
Other conditions that cause koilonychia include hemochromatosis (iron overload), iron deficiency anemia, diabetes, hypothyroidism, psoriasis, and lupus.
Spoon nails as shown by the prominent dent or press (Source: Wikimedia Commons)
Did You Know? Iron deficiency anemia is common among women and can be easily overlooked. Learn about how serious iron deficiency anemia can get to take proper action to restore your health.
- Beau’s Lines
When you see a deep dent or depression formed horizontally on your fingernails or toenails, this is referred to as Beau’s lines2, named after the physician who described it, Joseph Beau.
Beau’s line can be linked to any temporary interruption in nail growth, particularly during cell division. Nails tend to grow out straight. But if something disturbs the smooth process, it could sustain a linear groove amidst the plat.
People with acute kidney disease or renal failure often develop Beau’s lines due to its adverse impact on the body’s metabolic process. As a result, it disrupts normal growth, including that of your nails.
Beau’s lines with the sharp indentation (Source: Wikimedia Commons)
- Lindsay’s Nails
Also called half-and-half nails, Lindsay’s nails have the bottom half of the nail plate colored white, and the upper half either has a red or brown color. This condition may occur due to uremia (serum toxin buildup) or acidosis due to impaired glomerular filtration.
About 20% to 50%3 of those with kidney disease have Lindsay’s nails. It’s also more common on toenails than on fingernails. The discoloration may not be removed for people undergoing dialysis, but it could disappear among those who have undergone a kidney transplant.
Half-and-half nails or Lindsay’s nails showing the separate colors of the nail plate (Source: Wikimedia Commons)
Did You Know? Lindsay’s nails can also show in liver disease. But the most common nail problem associated with hepatic or liver disease is Terry’s nail. It is a type of discoloration notable for its ground glass opacity that makes the nail appear washed out.
- Yellow Coloration
It’s hard not to notice nails that start to turn yellow. The discoloration is localized on one area of your nail plate but could also coat the entire surface. This yellow coloring can be linked to nitrogen waste accumulation in the blood, which could indicate chronic kidney disease (CKD)4.
An excellent way to monitor toxic waste buildup is to get screened for these common byproducts regularly. Your healthcare provider may recommend getting the blood urea nitrogen (BUN) test and creatinine blood test.
Yellow coloration on the tip of the fingernails
- Detached Nails
If your nails start to separate from the skin, it could signal chronic renal failure5. This condition is called onycholysis.
The separation of the nail plate from the nail bed can be partial or complete. Either way, it exposes a vulnerable part of your fingers and toes to infection that further aggravates the condition.
A nail detaching from the nail bed (Source: Wikimedia Commons)
- Brittle Nails
With kidney disease, your nails may start to lose quality and integrity. It could become brittle and ridged or easily broken with light injuries. Additionally, having brittle nails may imply that you’re low in keratin. Consult your doctor immediately so your renal diet can be adjusted, if possible.
A brittle nail sustaining damage from a light scratch (Source: Wikimedia Commons)
Why Do Nails Change With Kidney Disease?
If you have renal disease or other conditions affecting your kidneys and blood circulation, your body will have difficulties eliminating waste products like BUN and creatinine. Without a functioning filtering system to remove them, these substances can build up in the bloodstream, causing prominent changes in the body.
In the case of patients with kidney disease, fingernails and toenails will start to change in form, texture, and coloration as nitrogen becomes excessive.
Additionally, some renal diets for kidney disease also limit specific nutrient quantities to prevent overloading the already-limited filtration function of the kidneys. As a result, you may suffer from nutrient deficiencies that affect keratin production. Keratin is a protein responsible for strengthening the nails and preventing hair loss.
When To See A Doctor
While kidney disease and nails may seem to have a direct connection, taking note of the changes in your fingernails and toenails will not be enough to assess the severity of the medical condition.
Still, a significant change in your nails could warrant a visit to your doctor. If your nail looks far off from what is normal and you exhibit other symptoms of chronic kidney disease like shortness of breath, irregular urination, blood in urine, insomnia, and muscle cramps, schedule an appointment with your physician immediately.
Frequently Asked Questions
How do I check if my kidneys are OK?
The surest way to check your kidney’s health is through kidney function tests. Your doctor may order lab work as simple as a urinalysis or multiple blood tests such as those in a comprehensive metabolic panel (CMP14). It will depend on your symptoms, family history, and risk for developing specific kidney disorders.
Does kidney health also affect hair?
Chronic kidney disease can lead to hair loss because the severe impairment in the kidneys’ glomerular filtration results in vitamin, mineral, and protein deficiencies, which affects hair growth. As with nails, hair needs keratin, which becomes limited with CKD.
What other diseases show up in your nails?
Aside from renal disease, changes in your nails can reveal other medical problems, such as heart disease, lung issues, inflammatory bowel disease (IBD), Reiter’s syndrome, liver disease, psoriasis, diabetes, and thyroid disease.
The Bottom Line
Although kidney disease primarily affects your internal physiology, it doesn’t take long before your outward appearance catches up and starts to decline. For some, the so-called “renal failure nails” are apparent symptoms of kidney disease or even kidney failure, but for others, they may appear as unimportant alterations. However, given the complications of renal disease, it is imperative to spot the nail problem’s severity.
Sources:
1 Lakshmi BS, Ram R, Kumar VS. Nail changes in a renal patient. Indian J Nephrol. 2015 Nov-Dec;25(6):383. doi: 10.4103/0971-4065.152727. PMID: 26664218; PMCID: PMC4663780.
2 Pérez Pico AM, Dorado P, Santiesteban MÁ, Mingorance-Alvarez E, García-Bernalt Funes V, Mayordomo R. Prevalence of foot disorders according to chronic kidney disease stage. J Ren Care. 2021 Mar;47(1):17-26. doi: 10.1111/jorc.12342. Epub 2020 Jul 30. PMID: 33216453.
3 Raja, S. M. (2021). Chronic kidney disease entertained from Lindsay’s nails: A case report and literature review. Clinical Case Reports, 9(7). https://doi.org/10.1002/ccr3.4426
4 Goel, V., Sil, A., & Das, A. (2021). Cutaneous Manifestations of Chronic Kidney Disease, Dialysis and Post-Renal Transplant: A Review. Indian Journal of Dermatology, 66(1), 3-11. https://doi.org/10.4103/ijd.IJD_502_20
5 Aqil N, Nassiri A, Gallouj S, Mernissi FZ (2019) Nail Disorders in Patients with Chronic Renal Failure. J Dermatol Res Ther 5:065. doi.org/10.23937/2469-5750/1510065
