Amyloidosis & Sarcoidosis

Question 1

What is amyloidosis?

Answer 1

Multisystem disorder caused by abnormal folding of proteins and their deposition as amyloid fibrils in tissues, disrupting their normal function

Question 2

What is sarcoidosis?

Answer 2

Multisystem disorder of unknown aetiology, commonly affecting young adults, and characterised by non-caseating granulomas in many tissues

Question 3

State at least 3 types of amyloidosis

Answer 3

AL amyloidosis (primary), AA amyloidosis (secondary), haemodialysis-associated amyloidosis, familial amyloidosis

Question 4

Describe the histology of sarcoidosis

Answer 4

Non-caseating granulomas, Schaumann bodies, asteroid bodies (inclusions of protein and calcium)

Question 5

Define secondary amyloidosis

Answer 5

Deposition of amyloid formed from serum amyloid A, an acute phase protein, secondary to chronic infection or inflammation

Question 6

Name two conditions associated with AL amyloidosis

Answer 6

Plasma cell dyscrasias, paraproteinaemias (e.g. monoclonal gammopathy of unknown significance, multiple myeloma, CLL)

Question 7

Describe the investigation results in AL amyloidosis

Answer 7

Monoclonal immunoglobulin, free light chains in serum and urine (Bence Jones proteins), increased bone marrow plasma cells

Question 8

Name at least two autoimmune and two other causes of AA amyloidosis

Answer 8

Autoimmune: rheumatoid arthritis, ankylosing spondylitis, inflammatory bowel disease
Other: TB, osteomyelitis, renal cell carcinoma, Hodgkin’s lymphoma

Question 9

What is deposited in haemodialysis-associated amyloidosis?

Answer 9

Beta-2-microglobulin

Question 10

State the most common type of familial amyloidosis and its inheritance pattern

Answer 10

Familial Mediterranean Fever (autosomal recessive)

Question 11

Describe the histology of amyloidosis

Answer 11

Apple green birefringence when stained with Congo Red and viewed under polarised light (due to beta pleated sheet configuration)

Question 12

In which group is sarcoidosis most severe?

Answer 12

Those of Afro-Caribbean descent

Question 13

Which organ is most commonly affected by sarcoidosis?

Answer 13

Lungs

Question 14

Describe the appearance of sarcoidosis on chest x-ray

Answer 14

Bilateral hilar lymphadenopathy, fine nodular shadowing in mid zones (pulmonary infiltrates)

Question 15

Describe the typical clinical symptoms of sarcoidosis

Answer 15

Insidious-onset of dyspnoea, cough, chest pain, and night sweats

Question 16

Describe the clinical features of amyloidosis on the heart

Answer 16

Conduction defects, heart failure, cardiomegaly

Question 17

Describe the clinical features of amyloidosis on the liver and kidneys

Answer 17

Nephrotic syndrome, hepatosplenomegaly

Question 18

What is the most common presentation of amyloidosis?

Answer 18

Nephrotic syndrome

Question 19

What % of patients with amyloidosis get macroglossia?

Answer 19

10%

Question 20

Describe the pathophysiology of familial Mediterranean fever

Answer 20

Abnormalities in pyrin lead to increased production of IL-1, causing attacks of fever and inflammation of serosal surfaces (pleura, peritoneum, synovium) with predominantly renal deposition of AA amyloid

Question 21

State the dermatological manifestations of sarcoidosis

Answer 21

Erythema nodosum, lupus pernio, skin nodules

Question 22

State the bone and joint manifestations of sarcoidosis

Answer 22

Arthritis, bone cysts

Question 23

State the ocular manifestations of sarcoidosis

Answer 23

Anterior uveitis, posterior uveitis, uveoparotid fever, parotid enlargement (may cause facial nerve palsy), keratoconjunctivitis, lacrimal gland enlargement

Question 24

Describe the symptoms of anterior and posterior uveitis

Answer 24

Anterior: painful red eye, misting of vision
Posterior: progressive visual loss

Question 25

Describe the haematological manifestations of sarcoidosis

Answer 25

Leukopaenia, anaemia

Question 26

Describe the cardiac manifestations of sarcoidosis

Answer 26

Arrhythmias, cardiomyopathy, conduction defects

Question 27

Describe the metabolic manifestations of sarcoidosis

Answer 27

Hypercalcaemia, hypercalciuria -> renal calculi and nephrocalcinosis

Question 28

State the constitutional symptoms of sarcoidosis

Answer 28

Malaise, fever, weight loss, night sweats

Question 29

Describe the investigation results in sarcoidosis

Answer 29

Hypercalcaemia, raised ESR, raised ACE. Transbronchial biopsy shows non-caseating granulomas