All the following diseases are associated with HILA B – 27 & Uveitis, except –
## **Core Concept**
The question assesses the association between specific diseases, HLA-B27, and uveitis. HLA-B27 is a subtype of human leukocyte antigen (HLA) and is linked to several autoimmune conditions, particularly those affecting the musculoskeletal system and eyes. Uveitis, an inflammation of the uvea in the eye, can be associated with various systemic diseases, including those linked to HLA-B27.
## **Why the Correct Answer is Right**
The correct answer, **D. Psoriatic Arthritis**, while it can have ocular manifestations, is less commonly associated directly with HLA-B27 and uveitis compared to the strong associations seen with ankylosing spondylitis, reactive arthritis, and inflammatory bowel disease. HLA-B27 is notably associated with anterior uveitis, particularly in the context of spondyloarthropathies like ankylosing spondylitis.
## **Why Each Wrong Option is Incorrect**
- **Option A: Ankylosing Spondylitis** is strongly associated with HLA-B27 and uveitis. The link between ankylosing spondylitis, HLA-B27, and uveitis is well established, making this option incorrect as an exception.
- **Option B: Reactive Arthritis** also shows a significant association with HLA-B27 and can present with uveitis among its extra-articular manifestations. Therefore, it is not the correct exception.
- **Option C: Inflammatory Bowel Disease (IBD)** can be associated with uveitis and has a link with HLA-B27, although the association might not be as strong as with ankylosing spondylitis. Nonetheless, it does not serve as the exception regarding the association with HLA-B27 and uveitis.
## **Clinical Pearl / High-Yield Fact**
A key point to remember is that HLA-B27 is associated with a group of conditions known as spondyloarthropathies, which include ankylosing spondylitis, reactive arthritis, psoriatic arthritis, and enteropathic arthritis associated with inflammatory bowel disease. Among these, ankylosing spondylitis has a particularly strong association with both HLA-B27 and acute anterior uveitis.
## **Correct Answer:** D. Psoriatic Arthritis