Differentials

Giant cell arteritis (GCA)

SIGNS / SYMPTOMS
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SIGNS / SYMPTOMS

Patients are usually older; average age is 74 years. May have polymyalgia rheumatica with proximal myalgia. Jaw claudication is common. Lower extremity involvement is less common.

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Imaging with CT or magnetic resonance angiography; GCA is more likely to have cranial artery involvement and less likely to have lower extremity involvement.

Essential hypertension

SIGNS / SYMPTOMS
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SIGNS / SYMPTOMS

Intact pulses and the absence of bruits. No marked difference in blood pressure between each side.

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Clinical diagnosis.

No stenoses on vascular imaging.

Syphilis

SIGNS / SYMPTOMS
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SIGNS / SYMPTOMS

Firm painless ulcer at site of primary inoculation, usually genital region. Symmetric non-itchy rash accompanies systemic symptoms.

INVESTIGATIONS

Positive syphilis serology.

Catheter or CT angiogram: typical calcification of the proximal ascending aorta.

Tuberculosis (TB)

SIGNS / SYMPTOMS
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SIGNS / SYMPTOMS

Persistent productive cough. Recent travel to an endemic area.

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Mantoux test: elicits delayed hypersensitivity reaction, which will be positive in people with latent infection, previously cleared infection, or in those previously immunized.

Chest x-ray: may show evidence of pulmonary TB foci.

Sputum culture: takes 4 to 12 weeks to culture acid-fast bacilli but is diagnostic if found.

Interferon-gamma release assay: blood test to detect interferon gamma production when incubated with TB bacilli. Can identify active and latent infection.

Spondyloarthropathy

SIGNS / SYMPTOMS
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SIGNS / SYMPTOMS

Back pain and stiffness lasting more than 1 hour, particularly in the mornings. Peripheral arthritis. May be preceded by urethritis or cervicitis in the case of reactive arthritis. Accompanying symptoms may include psoriasis, palmar-plantar pustulosis, iritis, uveitis, or conjunctivitis.

INVESTIGATIONS

X-ray of spine: may demonstrate sacroiliitis.

X-ray of peripheral joint affected by arthritis may show periarticular osteolysis in psoriatic arthritis.

Behçet disease

SIGNS / SYMPTOMS
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SIGNS / SYMPTOMS

A triad of oral and genital ulceration with uveitis. Often accompanied by a peripheral arthritis. May have thrombotic arterial and venous occlusions.

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Angiography: reveals saccular dilation of involved arteries or thrombotic occlusion.

Cerebrospinal fluid examination supportive but not diagnostic; increased inflammatory cells and protein.

Kawasaki disease

SIGNS / SYMPTOMS
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SIGNS / SYMPTOMS

Typically affects children under age 5 years. High-grade fever with strawberry-tongue-marked lymphadenopathy. Red eyes with uveitis or conjunctivitis. Rash and peeling of the skin on the palms and soles may be seen.

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Clinical diagnosis using set criteria.

Angiography reveals saccular dilation of coronary arteries if affected.

Marfan syndrome

SIGNS / SYMPTOMS
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SIGNS / SYMPTOMS

Typically tall people with long limbs. May have a family history of Marfan syndrome. Susceptible to lens dislocation.

Systemic signs and symptoms absent.

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Clinical diagnosis.

Family history.

Genetic testing rarely carried out.

Ehlers-Danlos syndrome

SIGNS / SYMPTOMS
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SIGNS / SYMPTOMS

May have hypermobile joints or paper-thin skin scars.

Systemic signs and symptoms absent

INVESTIGATIONS

Angiography: if vascular wall collagen affected, may reveal saccular dilation of involved arteries.

Genetic testing.

Atherosclerosis

SIGNS / SYMPTOMS
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SIGNS / SYMPTOMS

More common in men, may have associated risk factors of hypertension, smoking, diabetes mellitus, and raised cholesterol. Typically, patients are aged over 40 years.

INVESTIGATIONS

Angiography: typical abrupt narrowing of artery rather than tapered narrowing. Lesions usually at the vessel origin and carotid bifurcations.

Fibromuscular dysplasia

SIGNS / SYMPTOMS
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SIGNS / SYMPTOMS

Pulses present but may be diminished. Hypertension common and most commonly affects renal and carotid arteries.

INVESTIGATIONS

Angiography: characteristic beading of affected arteries. Aorta not usually involved.

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