Amyloid disorders: A disease where nothing is safe

For the past 30 years, Peter Gorevic, now director of rheumatology at Mount Sinai, has been treating patients with immune and arthritis-related disorders. One of his main research interests is looking at what causes the group of disorders known as amyloid diseases, and what doctors can do to treat them.

Who's at risk

Amyloid disease is hardly a household word, despite the fact that one of the 26 types is Alzheimer’s disease — which affects about 4 million Americans. "Amyloid diseases, or amyloidosis, are conditions in which the abnormal amyloid proteins build up in organs and tissues," says Gorevic. "During a biopsy, the pathologist sees a pinkish amorphous material that is the sign of an unhealthy mutation," he says.

These amyloid deposits can occur anywhere in the body and cause different symptoms, depending on which organ is primarily affected. Doctors divide amyloid disease into systemic and localized disease, with localized disease often related to Alzheimer’s.

"Systemic amyloid falls into three groups: primary, secondary and familial amyloid," says Gorevic, "While these diseases are relatively uncommon, they do occur in certain settings more often than others."

For instance, one type of amyloid is a frequent complication resulting from long-term dialysis.

"Some researchers think that 60%-80% of patients who are on dialysis for more than 10 years may have amyloid," says Gorevic. "We estimate that about 250,000 Americans fall into this high-risk category."

Another common disease linked to amyloid is chronic inflammatory arthritis, which can cause secondary amyloid disease. "As many as 5%-10% of those people might develop amyloid if their arthritis isn’t kept under control," says Gorevic.

Familial amyloid is the rarest disorder, with only 10,000 to 15,000 people affected worldwide.

"The genetic mutation that causes it is widely represented in Western Africa, and as a result more prevalent in African-Americans," says Gorevic. "Some researchers think 1 million people carry the mutation that can lead to familial amyloid."

Signs and symptoms

Amyloid diseases present themselves differently, depending on the system that is primarily affected.

"Often patients end up with symptoms related to the kidney, heart, nervous system or GI tract," says Gorevic. "The symptoms may not be specific to amyloid, but they would lead the patient to come to the doctor, who runs a biopsy that catches the amyloid," he says.

For instance, amyloid patients commonly see a nephrologist if they are retaining fluid, losing protein in their urine or experiencing shortness of breath. Cardiologists more often find amyloid in patients who have swollen legs, chest palpitations and shorter and shorter breath. "Sometimes they can’t lie flat because fluid accumulates in their lungs," says Gorevic.

Neurological symptoms can include neuropathy (which cause numbness and tingling in the legs), carpal-tunnel syndrome or weakness in the legs and arms. In the GI system, red flags can come from the sense that the stomach fills up too quickly, trouble swallowing, dry mouth, diarrhea or constipation.

Traditional treatment

A thorough diagnosis is the key first step to treating amyloid disease.

"Traditionally, treatment is, first of all, figuring out what organ is involved and how it should be handled," says Gorevic. "For instance, if heart failure, what could you do? If the kidneys, how do we conserve function?" In this approach, cardiac patients might be helped by certain drugs and the need to avoid others.

Kidney patients would take "standard meds" like ACE inhibitors or ARBs (angiotensin receptor blockers). In both cases, organ transplant can be an option down the line. One of the primary objectives is that the treatment has to be tailored to the particular type of amyloid.

"For primary amyloid, we must first evaluate the patient for the bone marrow cancer multiple myeloma, which occurs in 10% of these patients," says Gorevic. "The treatment is chemotherapy."

In secondary amyloid, the amyloid results from another health problem, such as chronic inflammatory arthritis. Treating the underlying disease aggressively has great results in managing the amyloid." Familial amyloid is the most frustrating," says Gorevic. "It affects the nervous system or heart, and until recently we had no therapeutics."

New drugs are rapidly changing the landscape of treatments available for all three types of amyloid, with more rapid chemo and an improved understanding of bone marrow transplantation changing the prognosis for patients with primary amyloid.

New therapeutics can prevent secondary amyloid from forming, or prevent the need for kidney transplant.

Research breakthroughs

Doctors expect that two new drugs approved for rheumatoid arthritis will dramatically cut down on the resulting amyloid. In the past year, doctors have discovered a new therapeutic, diflunisal.

"It seems to inhibit this form of amyloid from occurring," says Gorevic. "It’s going through testing now, and we're very optimistic."

Questions for your doctor

If you’re diagnosed with amyloid disease, start out by asking "How much of my body is affected?" Be sure to consider the range of treatments by asking "What are my options?"

If your doctor recommends a medical treatment, ask, "What side effects can I expect from these drugs?" Many of the drugs that doctors prescribe to patients can be part of a study or involve an off-label use, "so it’s important for the patients to understand the risks and benefits," says Gorevic.


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