Features of seronegative spondyloahropathy include all of the following, Except:
**Core Concept**
Seronegative spondyloarthropathies are a group of inflammatory rheumatic diseases characterized by the absence of rheumatoid factor and HLA-DR4/DR1 positivity. These conditions are associated with the axial and peripheral joints, and extra-articular manifestations such as uveitis, psoriasis, and inflammatory bowel disease.
**Why the Correct Answer is Right**
These conditions are typically associated with the presence of HLA-B27, which is a major histocompatibility complex (MHC) class I antigen. The pathogenesis of seronegative spondyloarthropathies involves an abnormal immune response to environmental triggers, leading to a chronic inflammatory process. The involvement of the axial skeleton, particularly the spine and sacroiliac joints, is a hallmark feature of these conditions.
**Why Each Wrong Option is Incorrect**
**Option A:** Peripheral joint involvement is a characteristic feature of seronegative spondyloarthropathies, making this option incorrect.
**Option B:** Uveitis is a common extra-articular manifestation of seronegative spondyloarthropathies, making this option incorrect.
**Option C:** Psoriasis is a skin condition that is associated with seronegative spondyloarthropathies, making this option incorrect.
**Clinical Pearl / High-Yield Fact**
The presence of HLA-B27 is a strong risk factor for developing seronegative spondyloarthropathies, particularly ankylosing spondylitis. This association can be used to support the clinical diagnosis in patients with characteristic symptoms and signs.
**Correct Answer:** D