- Symptoms often mimic those seen in other diseases.
- Symptoms can appear between the ages of mid 20’s to 80’s but many do not appear until middle age.
- Symptoms will vary according to the mutation and degree of organ involvement.
- Most commonly symptoms are due to nerve and heart involvement.
- Each family will have its own pattern of organ involvement but there may be variations within families.
Symptoms caused by heart involvement.
Amyloid protein deposition into the heart can result in a type of heart failure causing the following symptoms:
- Shortness of breath, sometimes just after mild exertion, sometimes when lying flat.
- Palpitations due to abnormal heart rhythms, most frequently atrial fibrillation or atrial flutter.
- Ankle swelling (oedema).
- Fatigue, nausea, weight loss.
- Dizziness and fainting, may occur after exertion, or after eating.
- Disrupted sleep.
- Angina (chest pain)
Symptoms caused by Peripheral and Autonomic nerve involvement
Amyloid deposition in the peripheral and autonomic nerves causing the symptoms below:
- Numbness, tingling, pins and needles in the feet and hands
- Weakness and pain in the arms and legs
- Loss of sensation and feeling making it difficult to distinguish heat and cold.
- Dizziness or fainting on standing
- Diarrhoea or constipation, or sometimes both
The eye many be involved resulting in blurred vision and vision loss.
Other organ involvement below is rare:
- Thyroid gland
- Adrenal gland
- Blood Vessels
A diagnosis of amyloidosis can only definitively be made through a tissue or organ biopsy:
- A tissue biopsy involves taking a small piece of tissue from the body, often the fat pad on the tummy the gastrointestinal tract, the lip or the bone marrow. Sometimes a more invasive biopsy may be taken from the symptomatic organs, the heart or nerves.
- The biopsy is stained with the dye Congo red in the laboratory.
- If amyloid is present, the biopsy will appear red under normal light and green (apple-green birefringence) under special polarized light.
- Occasionally the diagnosis can be made without a tissue biopsy because a DPD or PYP scan shows amyloid in the heart or because genetic testing confirms the diagnosis
2nd procedure in the laboratory
- Further testing of the biopsy may be done to identify the type of amyloidosis by identifying the protein composition of the amyloid fibrils.
- It is important to identify the “type” as treatment is different for each type of amyloid.
The existence of a family history of hereditary ATTR may greatly assist in diagnosing the type of the disease. However, a number of people diagnosed with ATTRv will have no known family history.
Tests listed below may be performed to help with the diagnosis, typing and assessment of organ involvement and damage and to form a treatment plan. Some of these tests will be repeated over time to monitor the result of any treatment and disease progress.
- Genetic testing to analyze the TTR gene associated with this type of hereditary amyloidosis
- MRI of the heart (troponin and BNP or NT-ProBNP)
- Nerve conduction tests
- DPD or PYP scan.
(Traditionally used for imaging bones, these scans involve special molecules which are injected into the body and become trapped in the heart when it is full of transthyretin amyloidosis thus helping with the diagnosis and identification of this type of amyloid.
- Urine analysis
- Eye tests