AL Amyloidosis

Question 1

What is amyloidosis?

Answer 1

Amyloidosis is a clinical disorder caused by extracellular and/or intracellular deposition of insoluble abnormal amyloid fibrils that alter the normal function of tissues

Question 2

What is AL amyloidosis?

Answer 2

AL amyloidosis results from extra-cellular deposition of fibril-forming monoclonal immunoglobulin light chains, which can be caused by myeloma

Question 3

What are some causes of amyloidosis?

Answer 3

Hereditary conditions
Age
Chronic inflammation

Question 4

How does AL amyloidosis present?

Answer 4

Weakness
Dyspnoea
Heavy proteinuria
Impaired renal function (60%)
Restrictive cardiomyopathy (50%)
Autonomic and peripheral neuropathy
GI malabsorption

Question 5

How is AL amyloidosis initially diagnosed?

Answer 5

Organ biopsy

Question 6

What stain is used in diagnosis of AL amyloidosis?

Answer 6

Congo red stain - Shows apple-green birefringence

Question 7

What tests can be used to confirm other organ involvement in AL amyloidosis?

Answer 7

• ‘SAP’ scan
• Echocardiogram/cardiac MRI
• Nephrotic range proteinuria

Question 8

What is a SAP scan?

Answer 8

Indium-123 labelled serum amyloid scintigraphy (SAP) localises rapidly and specifically to amyloid deposits in proportion to the quantity of amyloid present, showing disease burden and response

Question 9

How is Al amyloidosis managed?

Answer 9

Treatment of AL amyloidosis is based on chemotherapy (similar to myeloma)

The presence and severity of amyloid heart disease is the main adverse prognostic factor