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Ankylosing spondylitis differential diagnosis

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] ; Associate Editor(s)-in-Chief: Vamsikrishna Gunnam M.B.B.S [2]

Overview

Overview

Ankylosing spondylitis must be differentiated from other diseases causing reactive arthritis,rheumatoid arthritis and psoriatic arthritis.

Preferred Table

Preferred Table

Arthritis Type Clinical Features Body Distribution Key Signs Laboratory Abnormalities
History of Psoriasis Symmetric joint involvement Asymmetric joint involvement Enthesopathy Dactylitis Nail Dystrophy Human immunodeficiency virus association Upper extremity-hands Lower extremity Sacroiliac joints Spine Osteopenia Joint Space Ankylosis Periostitis Soft tissue swelling ESR Rheumatoid factor (RF) HLA-B27
Psoriatic arthritis + + ++ + + + + +++ (DIP/PIP) +++ ++ (Unilateral) ++ ++ (Widening) ++ +++ (Fluffy) ++ + 30-75%
Rheumatoid arthritis ++ + +++

(MCP/wrist)

+++ + (Unilateral) ++(Cervical) +++ +++ (Narrowing) + + (Linear) +++ +++ +++ 6-8%
Ankylosing spondylitis +++ + + + +++ (Bilateral) +++ +++ ++ (Narrowing) +++ +++ (Fluffy) + +++ 90%
Reactive arthritis (Reiter’s syndrome) +++ + + ++ +++ ++ (Unilateral) + + + (Narrowing) +++ (Fluffy) ++ ++ 75%

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