Systemic lupus erythematosus

Question 1

What is the gender ratio for systemic lupus erythematosus (SLE)?

Answer 1

SLE is much more common in females, with a ratio of 9:1 (F:M).

Question 2

In which communities is systemic lupus erythematosus more common?

Answer 2

SLE is more common in Afro-Caribbeans and Asian communities.

Question 3

What is the typical age of onset for systemic lupus erythematosus?

Answer 3

The onset of SLE is usually between 20 to 40 years.

Question 4

How has the incidence of systemic lupus erythematosus changed over the past 50 years?

Answer 4

The incidence of SLE has risen substantially, increasing threefold using American College of Rheumatology criteria.

Question 5

What type of hypersensitivity reaction is systemic lupus erythematosus?

Answer 5

SLE is classified as an autoimmune disease and a type 3 hypersensitivity reaction.

Question 6

What genetic associations are linked to systemic lupus erythematosus?

Answer 6

SLE is associated with HLA B8, DR2, and DR3.

Question 7

What causes systemic lupus erythematosus?

Answer 7

SLE is thought to be caused by immune system dysregulation leading to immune complex formation.

Question 8

What organs can be affected by immune complex deposition in systemic lupus erythematosus?

Answer 8

Immune complex deposition in SLE can affect any organ, including the skin, joints, kidneys, and brain.

Question 9

How does the incidence of systemic lupus erythematosus in black Africans compare to black Americans?

Answer 9

The incidence of SLE in black Africans is said to be much lower than in black Americans, though the reasons for this are unclear.

Question 10

What is systemic lupus erythematosus (SLE)?

Answer 10

A multisystem, autoimmune disorder that typically presents in early adulthood and is more common in women and people of Afro-Caribbean origin.

Question 11

What are general features of SLE?

Answer 11

Fatigue, fever, mouth ulcers, lymphadenopathy.

Question 12

What skin features are associated with SLE?

Answer 12

Malar (butterfly) rash, discoid rash, photosensitivity, Raynaud’s phenomenon, livedo reticularis, non-scarring alopecia.

Question 13

Describe the malar (butterfly) rash in SLE.

Answer 13

It spares the nasolabial folds.

Question 14

Describe the discoid rash in SLE.

Answer 14

A scaly, erythematous, well demarcated rash in sun-exposed areas that may progress to become pigmented and hyperkeratotic before becoming atrophic.

Question 15

What musculoskeletal features are associated with SLE?

Answer 15

Arthralgia and non-erosive arthritis.

Question 16

What cardiovascular features are associated with SLE?

Answer 16

Pericarditis (the most common cardiac manifestation) and myocarditis.

Question 17

What respiratory features are associated with SLE?

Answer 17

Pleurisy and fibrosing alveolitis.

Question 18

What renal features are associated with SLE?

Answer 18

Proteinuria and glomerulonephritis (diffuse proliferative glomerulonephritis is the most common type).

Question 19

What neuropsychiatric features are associated with SLE?

Answer 19

Anxiety and depression, psychosis, seizures.

Question 20

What percentage of patients with systemic lupus erythematosus are ANA positive?

Answer 20

99% are ANA positive

This high sensitivity makes it a useful rule out test, but it has low specificity.

Question 21

What percentage of patients with systemic lupus erythematosus are rheumatoid factor positive?

Answer 21

20% are rheumatoid factor positive.

Question 22

What is the specificity and sensitivity of anti-dsDNA antibodies?

Answer 22

Anti-dsDNA: highly specific (> 99%), but less sensitive (70%).

Question 23

What is the specificity and sensitivity of anti-Smith antibodies?

Answer 23

Anti-Smith: highly specific (> 99%), sensitivity (30%).

Question 24

What other antibodies are associated with systemic lupus erythematosus?

Answer 24

Also: anti-U1 RNP, SS-A (anti-Ro) and SS-B (anti-La).

Question 25

What inflammatory marker is generally used for monitoring systemic lupus erythematosus?

Answer 25

ESR is generally used.

Question 26

What does a raised CRP indicate during active disease?

Answer 26

A raised CRP may indicate underlying infection.

Question 27

What happens to complement levels (C3, C4) during active disease?

Answer 27

Complement levels (C3, C4) are low during active disease.

Question 28

What can anti-dsDNA titres be used for?

Answer 28

Anti-dsDNA titres can be used for disease monitoring ## Footnote Note that anti-dsDNA is not present in all patients.

Question 29

What is the treatment of choice for systemic lupus erythematosus (SLE)?

Answer 29

Hydroxychloroquine

Question 30

What should be considered if there is internal organ involvement in SLE?

Answer 30

Consider prednisolone or cyclophosphamide ## Footnote Examples of internal organ involvement include renal, neuro, and eye issues.

Question 31

What are two basic management strategies for SLE?

Answer 31

NSAIDs and sun-block

Question 32

What is lupus nephritis?

Answer 32

Lupus nephritis is a severe manifestation of systemic lupus erythematosus (SLE) that can result in end-stage renal disease.

Question 33

How should SLE patients be monitored for renal complications?

Answer 33

SLE patients should be monitored by performing urinalysis at regular check-up appointments to rule out proteinuria.

Question 34

What are the WHO classifications of lupus nephritis?

Answer 34

1. Class I: normal kidney 2. Class II: mesangial glomerulonephritis 3. Class III: focal (and segmental) proliferative glomerulonephritis 4. Class IV: diffuse proliferative glomerulonephritis 5. Class V: diffuse membranous glomerulonephritis 6. Class VI: sclerosing glomerulonephritis

Question 35

Which class of lupus nephritis is the most common and severe?

Answer 35

Class IV (diffuse proliferative glomerulonephritis) is the most common and severe form.

Question 36

What are the characteristic findings of renal biopsy in Class IV lupus nephritis?

Answer 36

1. Glomeruli show endothelial and mesangial proliferation, 'wire-loop' appearance. 2. If severe, the capillary wall may be thickened secondary to immune complex deposition. 3. Electron microscopy shows subendothelial immune complex deposits. 4. Granular appearance on immunofluorescence.

Question 37

What is the management for lupus nephritis?

Answer 37

1. Treat hypertension. 2. Initial therapy for focal (class III) or diffuse (class IV) lupus nephritis includes glucocorticoids with either mycophenolate or cyclophosphamide. 3. Mycophenolate is generally preferred to azathioprine to decrease the risk of developing end-stage renal disease.