The symptoms of amyloidosis vary widely due to the many different parts of the body that can be affected by the disease. If amyloid protein accumulates in a single part of the body, the disease is referred to as localised amyloidosis, while disease characterized by deposits that affect multiple organs and tissues is referred to as systemic. Localized amyloidosis is usually less serious than the systemic form.

Diagnosis is also complicated by the fact that the symptoms of amyloidosis are similar to those seen in other conditions that affect certain organs. Furthermore, disease progression is usually very slow and it may be years before enough amyloid protein accumulates for symptoms to begin, at which stage the organ is often already severely damaged.

Generalized symptoms include:

• Extreme weakness and tiredness
• Loss of appetite
• Unexplained loss of weight
• Irritable bowel syndrome and digestive problems
• Obstructive sleep apnea that may give rise to snoring
• Erectile dysfunction or impotence
• Skin lesions leading to rashes, itching and spots of blood.
• Chronic joint pain, particularly in the wrist, legs and feet. Tingling and numbness in the hands and feet is also common, as is Carpal tunnel syndrome.
• Fluid retention causing swelling of the legs and edema
• Shortness of breath
• Light-headedness or dizziness
• Hoarseness of voice
• Tongue may be enlarged and affected by plaques, blood spots or blisters

Examples of specific symptoms that occur as a result of localized disease include:

Kidney – This is the organ most commonly affected by primary and secondary amyloidosis. The organ is rarely affected in the familial forms caused by transthyretin mutations. Common features associated with kidney damage include proteinuria (elimination of protein in the urine), edema and high blood cholesterol. Less commonly, renal involvement may also lead to azotemia.

Heart – Amyloid deposits in the heart leads to thickening of the ventricular walls and enlargement of the organ which can cause heart failure. The heart is rarely affected in familial amyloidosis and secondary amyloidosis.

Nervous system – The nervous system is commonly affected in primary amyloidosis and can also be seen in some familial forms of the condition such as Met 30, originally known of as familial amyloid polyneuropathy. Symptoms may manifest as painless sensory changes or as neuropathic pain. In familial amyloidosis, neuropathy may lead to various symptoms including bladder and bowel changes, postural hypotension and erectile dysfunction.

Liver and gastrointestinal tract – The liver is affected in primary and secondary amyloidosis but rarely in the familial form of the disease. The liver may become enlarged and hardened and the alkaline phosphatase level may be elevated. Liver failure may also develop. Symptoms include diarrhea, loss of taste, difficulty in eating solid foods, bleeding in the gastrointestinal tract and weight loss.

Skin and soft tissues - Primary amyloidosis may affect the skin and soft tissues and cause blood spots called purpura, itching and rashes.

Lungs and vocal cords – In primary amyloidosis, deposits often accumulate in the lungs. The vocal cords may also be affected, causing hoarseness of voice.

Endocrine organs such as the thyroid gland and adrenal glands are rarely involved.