Module 10.1 - Autoimmune diseases

Question 1

What is giant cell arteritis?

Answer 1

A systemic inflammation of all structural layers of an artery/arteries (i.e., pan arteritis), typically the temporal artery or aorta, that tends to be associated (50%) with a diagnosis of polymyalgia rheumatica (PMR). It is the most common systemic vasculitis and typically only presents in individuals > 50 years of age.

Question 2

What are the symptoms associated with giant cell arteritis?

Answer 2

Giant Cell Arteritis should be considered in any patient > 50 years of age who presents with one of the following symptoms:

• New onset persistent headaches
• Abrupt onset of visual disturbance-especially transient monocular vision loss
• Jaw or arm claudication
• Unexplained fever, anemia, weight loss
• Throat pain
• High erythrocyte sedimentation rate (ESR) and/or high serum C-reactive protein (CRP)
• Difficulty talking
• Fever
• Temporal artery- nodular, pulseless
• Blindness
• Carotid bruits; asymmetry of pulses in arm, unequal upper extremity blood pressures

Question 3

What are the lab/diagnostic findings associated with GCA?

Answer 3

The diagnosis of Giant Cell Arteritis is can be made on histopathology or imaging studies. Histopathology is usually obtained from temporal artery biopsy. Color Doppler Ultrasound may also be used as a substitute for biopsy if available.

• CT angiogram with arterial narrowing finding
• Normal WBC count
• Elevated ESR, usually > 50mm/hr.
• +/- elevation in C-reactive protein (not always present)
• Mild normochromic and normocytic anemia
• Gold standard is biopsy of affected artery

Question 4

How do you manage GCA?

Answer 4

A. Begin Prednisone immediately upon clinical diagnosis (if strongly suspected and concern for site loss)

• Do not wait on biopsy. Biopsies obtained 1-2 weeks after initiation of steroids are reliable.

B. Intravenous methylprednisolone, 1 gram daily x 3 days in patients with visual loss.

C. Prednisone 40-60mg/day for 6 weeks – 2 months

D. Prednisone may be tapered after 6 week-2months if symptoms have subsided

E. Falling ESR can be used as a guide to when to begin tapering, but never before 6 weeks of steroid therapy has been completed.

F. Patient education on signs/symptoms of recurrence- high risk of recurrence.

Question 5

What is Systemic Lupus Erythematosus (SLE)?

Answer 5

A chronic inflammatory disease of unknown origin (autoimmune) that affects multiple body systems and is characterized by exacerbations and remissions.

• Characterized by autoantibody production, deposition of immune complexes, complement activation and tissue destruction/vasculitis
• Increased risk of cardiovascular disease and renal disease
• Ranges from mild joint and skin involvement to severe renal, hematologic, CNS involvement and fatality.
• Production of a number of antinuclear antibodies (ANA) are a prominent feature of SLE.
• Diagnosis is based on clinical judgment, excluding alternative diagnoses.

Question 6

Describe the etiology associated with SLE

Answer 6

• Occurs more often in African American women.
• Familial risks have been identified.
• Incidence of SLE is 5/100,000 in U.S
• Peak age at onset of SLE 20-40 years old
• Females: Males = 9:1

Question 7

What are the clinical manifestations associated with SLE?

Answer 7

1. Skin changes (73 % at onset): Butterfly rash, photosensitivity, mucus membrane lesion, alopecia, Raynaud’s phenomenon, purpura, urticaria

2. Arthritis/arthralgia (62-67% at onset) *joint symptoms with or without synovitis is often the earliest symptoms (non-erosive arthritis)

3. Fatigue (50% at onset)

4. Fever (36% at onset)
5. Renal disease (16-38% at onset)
6. Weight loss (21% at onset)

Other: Ocular changes, heart failure from myocarditis/hypertension, pericarditis, pleural effusions, post prandial abdominal pain, cognitive impairments, depression, neuropathies, seizures

Question 8

What are the lab/diagnostic findings associated with SLE?

Answer 8

*There is NO single laboratory marker for SLE disease activity and NO specific test is diagnostic; Clinical findings and laboratory tests are utilized as the basis for diagnosis.

Serum antinuclear antibody (ANA) – present in most patients, sensitive, but not specific; titers < 1:160 usually false positive.

Other labs which may show abnormalities:

• Anemia (Hgb < 12 grams/dl)
• Leukopenic (WBC < 4,000/mm)
• • Anticardiolopin antibody test
• • Direct Coomb’s test
• Proteinuria
• Hematuria
• Antibody to native DNA
• Antibody to Sm
• False + serology to syphilis
• Thrombocytopenia (< 100,000)
• Antiphospholipid antibodies
• Hypocomplementemia

Question 9

How do you manage a patient with SLE?

Answer 9

A. Treatment is supportive.

B. Sunscreens/glasses for photosensitivity

C. Topical steroid creams- for discoid lupus

D. NSAIDs – for joint symptoms

E. Hydroxychloroquine, 200-400mg daily for flare prevention.

F. Prednisone, 1-2 mg/kg/day for exacerbations- taper with inactivity of symptoms

G. Pulsed steroid therapy for life-threatening exacerbations. Consult rheumatologist

H. Hospitalization if warranted.

I. Calcium supplementation with Vitamin D3 replacement- for long-term steroid therapy.

J. Warfarin- maintain INR 2-3 for patients with + anticardiolipin antibodies

K. Cytotoxic medications for life-threatening manifestations- including lupus nephritis. Consult Rheumatology.

L. Patient education: Rest/Sun avoidance. Smoking cessation.

Question 10

What are some complications that can occur with SLE?

Answer 10

• Infections
• Renal Disease
• Cardiovascular disease – leading cause of death in SLE patients
• Lupus nephropathy
• Thrombosis