Systemic Lupus Erythematosus

Question 1

Which ethnic groups have higher rates of SLE?

Answer 1

People of African, Asian, and Hispanic descent.

Question 2

What antibodies increase the risk of neonatal lupus?

Answer 2

Typically, the antibodies responsible are anti-SSA (anti-Ro) and anti-SSB (anti-La).

Question 3

Which is the most concerning cardiac complication that can be seen in infants with neonatal lupus?

Answer 3

Complete congenital heart block, which occurs in 1-3% of affected infants and requires pacemaker placement.

Question 4

What are the (4) common features of neonatal lupus?

Answer 4

Rash, cytopenias, hepatitis, and bradycardia from congenital heart block.

Question 5

What is the typical clinical course for infants affected by neonatal lupus who do not have cardiac manifestations?

Answer 5

Most noncardiac features resolve within 6 months as maternal antibodies disappear.

Question 6

What is the typical clinical course for cardiac abnormalities in infants born with neonatal lupus?

Answer 6

Cardiac manifestations are permanent and can require lifelong pacemaker dependence.

Question 7

How do patients with SLE typically present, and what are some (3) common manifestations of disease?

Answer 7

Patients typically present with malaise, fever, and/or weight loss. Common manifestations include arthritis (80-90%), rash (70-80%), and nephritis (50-60%).

Question 8

Is a positive ANA common in pediatric SLE?

Answer 8

Yes. A positive ANA occurs in almost all pediatric patients with SLE (98-9%).

Question 9

List 6 immunologic laboratory findings one might expect to find in a patient with SLE.

Answer 9

Positive ANA (98-99%), anti-dsDNA (60-70%), anti-Smith (33%), antiphospholipid (50%), anti-U1 RNP (least common antibody), and hypocomplementemia.

Question 10

The presence of what two antibodies is associated with renal involvement in patients with SLE?

Answer 10

Anti-dsDNA and anti-Smith antibodies.

Question 11

With what are antiphospholipid antibodies associated?

Answer 11

These antibodies affect pathways of coagulation and increase the risk of miscarriages, thrombocytopenia, livedo reticularis, and/or blood clots in about 25% of patients.

Question 12

How do C3 and C4 levels correlate with disease activity in patients with SLE?

Answer 12

Complement proteins are consumed during immune complex formation in active SLE, particularly with nephritis. C3 and C4 often decline with active disease and may normalize with successful treatment.

Question 13

How is a diagnosis of SLE made?

Answer 13

A patient must meet at least 4 of 11 criteria for SLE diagnosis.

Question 14

What are the 11 possible criteria used to help make a diagnosis of SLE?

Answer 14

Neurologic disorder (seizures or psychosis); Malar rash; Discoid rash; Photosensitive rash; Oral and/or nasal ulcers; Serositis (pleuritis, pericarditis, peritonitis); Renal disorder (proteinuria or cellular casts); Arthritis; Hematologic disorder (hemolytic anemia, leukopenia, lymphopenia, or thrombocytopenia); Immunologic disorder (+ antiphospholipid ab, anti-dsDNA, anti-Smith, or false-positive syphilis test - either RPR or VDRL); presence of ANA.

Question 15

Describe the relationship between SLE and renal disease.

Answer 15

Renal involvement in SLE is very common and directly affects both morbidity and mortality.

Question 16

What are the 6 classes of lupus nephritis?

Answer 16

1. Minimal mesangial; 2. Mesngial proliferative; 3. Focal; 4. Diffuse segmental/Global; 5. Membranous; 6. Advanced Sclerosing.

Question 17

What is the most common cause of chorea in the U.S.?

Answer 17

SLE

Question 18

What laboratory testing should be performed if a patient with SLE presents with CNS dysfunction?

Answer 18

Lumbar puncture (b/c infection and hemorrhage are also possible in these patients). Serum antiribosomal P antibodies and antineuronal antibodies from the CSF can help to diagnose lupus psychosis or lupus cerebritis.

Question 19

What are the three characteristic skin findings in SLE?

Answer 19

Butterfly/Malar rash, discoid rash (uncommon in childhood SLE), and photosensitivity.

Question 20

Which two autoimmune diseases are signified by the finding of a malar rash?

Answer 20

A malar rash is usually due to either SLE or dermatomyositis.

Question 21

How would one distinguish between the malar rash of SLE/dermatomyositis and the similar-appearing rash associated with psoriasis and rosacea?

Answer 21

The malar rash involves the malar eminence but spares the nasolabial folds. The rash of psoriasis/rosacia involves the malar eminence but the nasolabial folds may also be involved.

Question 22

Which hair finding is common in SLE?

Answer 22

Alopecia

Question 23

What are the typical characteristics of mucosal lesions associated with SLE?

Answer 23

The lesions/ulcerations are typically painless and most commonly located on the hard palate or in the nares.

Question 24

What is subacute cutaneous lupus erythematosus?

Answer 24

It is uncommon and is characterized by a vesicular or bullous rash with the presence of anti-SSA and anti-SSB antibodies. This is the same rash and antibody profile seen in neonatal lupus. Some patients go on to develop full SLE, but may don’t and have less severe disease course.

Question 25

How does joint involvement differ between SLE and poJIA?

Answer 25

Early on, the two diseases may be difficult to distinguish. Over time, poJIA can show osteopenia and joint damage on x-ray; but in SLE, the x-rays are nonerosive even after years of arthritis.

Question 26

Which joint abnormality, common in SLE, is due to the disease itself, antiphospholipid antibody, and/or high-dose steroid usage?

Answer 26

Avascular necrosis

Question 27

Which musculoskeletal manifestation of SLE is a common cause of morbidity?

Answer 27

Avascular necrosis

Question 28

What is the most common cardiac abnormality in children with SLE?

Answer 28

Pericarditis, which occurs in 25-35% of patients with SLE.

Question 29

Which type of endocarditis is associated with SLE and antiphospholipid antibodies?

Answer 29

Libman-Sacks endocarditis (nonbacterial endocarditis with verrucous vegetations).

Question 30

List 5 potential pulmonary complications of SLE.

Answer 30

Pulmonary hemorrhage, infection, benign/indolent decreased diffusion capacity, pleuritis, and pleural effusion.

Question 31

What laboratory abnormalities are caused by the presence of lupus anticoagulant, and what is the clinical significance of its presence?

Answer 31

Lupus anticoagulant causes in vitro prolongation of PTT but not PT. These patients do not bleed excessively, but rather have an increased risk of arterial thrombosis, DVT, and thromboembolism.

Question 32

What is the most common endocrine abnormality in patients with SLE?

Answer 32

Antithyroid antibodies occur in nearly 50% of patients with SLE, and clinical hypothyroidism occurs in 10-20%. Graves disease also occurs but is much less common.

Question 33

Which drug class reduces lupus mortality and improves prognosis?

Answer 33

Antimalarial drugs (hydroxychloroquine)

Question 34

What are the four benefits of continuous antimalarial therapy in patients diagnosed with SLE?

Answer 34

Continuous antimalarial therapy prevents disease flares, decreases mortality in adult patients, lowers serum cholesterol levels, and decreases the risk for neonatal lupus in mothers who take the drug.

Question 35

List 8 common side-effects of long-term steroid use.

Answer 35

Avascular necrosis, osteoporosis with fracture or vertebral collapse, growth failure, glaucoma and cataracts, diabetes mellitus, HTN, accelerated atherosclerosis, and infection.

Question 36

Which complications of SLE are treated with low, medium, and high-dose corticosteroids?

Answer 36

Low dosages can be used to treat joint complaints and fatigue. Serositis responds to moderate dosing, but nephritis and CNS disease often require high-dose steroid therapy.

Question 37

What is the role of cyclophosphamide in treatment of SLE?

Answer 37

Cyclophosphamide has significant associated toxicity and is used mainly for initial control of aggressive disease.

Question 38

What two malignancies are more common in patients treated with cyclophosphamide? How can these risks be decreased?

Answer 38

Lymphoma and bladder carcinoma. The risk for lymphoma is an accumulated dose-related side effect which can be decreased by reducing the total dose of cyclophosphamide and switching to a less-toxic agent as soon as possible. The risk of bladder carcinoma is directly related to the development of hemorrhagic cystitis. Hemorrhagic cystitis can be prevented by administering mesna alongside IV cyclophosphamide.

Question 39

What two drugs are useful for long-term maintenance of aggressive SLE?

Answer 39

Mycophenolate mofetil and azathioprine.