In amyloidosis, abnormal proteins called amyloid deposits build up in different parts of the body. It’s like sand getting into the gears of a machine — it can grind, clog, or wear them down over time. Sometimes, amyloidosis is localized, meaning that it may only affect one part of the body. In other forms, it shows up in many parts of the body. Because amyloidosis often starts deep inside and doesn’t always cause clear symptoms, it can go unnoticed at first. This is especially true if it is not in a location you can see and is not getting in the way of key body functions.

When amyloidosis is systemic, meaning it affects the whole body, you may notice changes in unexpected places, including your nails. In addition, if you receive chemotherapy to treat AL amyloidosis (also called amyloid light-chain amyloidosis), it’s possible to have nail-related side effects. Not everyone with systemic amyloidosis or going through chemotherapy will have changes in their nails, but it’s something to be aware of. Here are some nail changes you may experience.

1. Brittle Nails

People with amyloidosis may develop brittle nails that are thin and break easily. Brittleness can also make your nails more prone to infection. Your healthcare provider may suggest a common home remedy of soaking your nails in a solution of 50 percent white vinegar and 50 percent water to help prevent bacterial or fungal infections. This treatment doesn’t help everyone, but it might be worth a try. You should also be gentle with your nails if they’re brittle.

Avoid getting manicures and pedicures that can expose you to germs. Don’t use harsh chemicals when washing your fingers and toes. Instead, choose fragrance-free soaps and lotions that are less irritating.

2. Long Bands

Lines that run the length of the nail can sometimes be linked to amyloidosis. They’re common, especially for people with dark skin. Up to 77 percent of Black adults over age 20 have natural dark bands on their nails. In addition, long ridges in the nails can be a normal sign of aging.

In rare cases, a dark line down the nail can be melanoma, a serious form of skin cancer. While most causes of long nail bands affect every nail, melanoma is more likely to show up in just one nail. If you notice a new or changing dark band on one nail, see a dermatologist right away to make sure it’s not melanoma.

3. Horizontal Ridges

Ridges that run side to side across the nail are also known as Beau’s lines. These horizontal markings can be a sign of any disease that’s severe enough to affect nail growth. They may also be associated with chemotherapy for amyloidosis. Healthy nails grow about a millimeter every six to 10 days. Chemo infusions temporarily stop the nails from growing. This disruption in the normal growth rate leaves a horizontal ridge across the nails.

Horizontal ridges can happen on both fingernails and toenails. You may be more likely to notice them on your fingers, especially if you work with your hands. The good news is that most chemo-related nail changes go away after treatment ends.

4. Nail Separation

Amyloidosis may lead to a condition called onycholysis, which is a separation of the nail plate from the nail bed. In onycholysis, the nail develops a white discoloration, similar to the top of the nail, where it’s detached from the skin.

Cases have been reported of people with amyloidosis developing onycholysis with slow-growing nodules under the toenail bed. Nails may also lift as a side effect of chemo. Clipping your nails short and removing the unattached parts can make it easier to manage onycholysis.

5. Inflammation-Related Changes

AA amyloidosis (also called secondary amyloidosis) is caused by an inflammatory condition like rheumatoid arthritis. This type of amyloidosis usually affects the kidneys, spleen, or liver. However, having an inflammatory condition can mean higher inflammation levels throughout your body that affect everything, including the nails. AL amyloidosis isn’t mainly caused by systemic inflammation like AA amyloidosis is. But inflammation around the nail bed can still happen for other reasons.

Nail symptoms of rheumatoid arthritis may overlap with those linked to amyloidosis (like longitudinal ridging). It’s not always possible to know why your nails are changing. Understanding that nail changes are signs of amyloidosis and related conditions should encourage you to bring up concerns with your healthcare provider so they can screen for other signs of disease.

Inflammation is also an issue for people receiving chemotherapy for AL amyloidosis. Chemo can damage the cuticles. If this happens, the area can become inflamed and more likely to get infected. You should promptly report any signs of inflammation or infection (discoloration, swelling, pain, or pus) to your healthcare team. In severe cases, this type of nail inflammation requires minor surgery.

Other Health-Related Nail Concerns

When you have a rare disease like amyloidosis, it’s easy to get hyperfocused on that one aspect of your health. However, nail changes can happen for various reasons. It’s important not to dismiss these symptoms, even if they’re not directly related to amyloidosis.

For example:

• Clubbed fingernails describe enlarged fingertips covered with rounded nails. It’s a gradual change that happens with lung, heart, liver, or digestive problems.
• Nail pitting (or dents) can be a sign of underlying skin or hair conditions like psoriasis, eczema, and alopecia (a condition that causes hair loss).
• Koilonychia (spoon nails) is when the nails curve upward at the edges. It may be related to liver problems or too much or too little iron.
• Yellow nails that are thick and grow slowly could be caused by lung conditions or lymphedema (swelling).

You know yourself best. During a routine physical examination, your healthcare provider may not notice subtle changes to your appearance or nails. But paying attention to these changes can help you and your doctor catch health problems early.

When Should You Call the Doctor?

Changes to your nails could be harmless. But they can also be a sign of amyloidosis or another health problem. That’s why it’s always a good idea to run any nail changes by your healthcare provider.

Even something as simple as weak or discolored nails could mean your amyloidosis is affecting new areas or that you’re having a side effect from treatment. While ridges aren’t always a cause for worry, you should call your doctor if your nails are painful or have an unusual odor. These could be signs of an infection that needs treatment. If your changes happen suddenly or get worse quickly, it’s time to reach out to your doctor.

Talk With Others Who Understand

MyAmyloidosisTeam is the social network for people with amyloidosis and their loved ones. On MyAmyloidosisTeam, more than 2,700 members come together to ask questions, give advice, and share their stories with others who understand life with this rare disease.

Has systemic amyloidosis affected your nails? If so, what kind of nail involvement or abnormalities do you experience? Share in the comments below, or start a conversation by posting on MyAmyloidosisTeam.