Seronegative spondyloarthropathies are a group of musculoskeletal diseases with clinical,
laboratory and genetic features in common.
They affect the axial skeleton,
are positive to HLAB27 gene and negative to rheumatoid factor.
This entity (spondyloarthritis) can be divided in five subgroups:
- Ankylosing spondylitis;
- Reactive arthritis (Reiter syndrome);
- Psoriatic arthritis;
- Arthritis associated with inflammatory bowel disease (Crohn disease or ulcerative colitis);
- Undifferentiated spondyloarthritis.
They affect both genders but are more frequent in men and usually start between the second and the fourth decades of life.
Clinical presentation is characterized by persistent inflammatory back pain for more than 3 months associated with morning stiffness that improves with exercise and worsens with rest.
Other commonly associated manifestations of disease are acute anterior uveitis,
psoriasis,
and inflammatory bowel disease,
as well as,
although more rare,
pericarditis,
cardiac valve involvement,
renal amyloidosis,
IgA nephropathy,
erythema nodosum and pulmonary fibrosis.
The laboratorial assessment of these patients relies on C-reactive protein concentration as it is the most important inflammatory marker of disease activity and no specific laboratory marker is recognized.
Imagiologic evaluation does not play a major role in differentiating between the different subtypes of spondylarthritis as they are similar,
but it’s important to identify the first signs of disease and thus make a proper diagnose.
They are characterized by the inflammatory involvement of the entheses,
usually affecting the axial skeleton and peripheral and sacroiliac joints (SIJ).
The treatment options available for patients with spondyloarthritis have been limited in the past,
using non-steroidal anti-inflammatory drugs to reduce spinal pain and physical therapy to maintain spinal mobility,
thus,
only symptomatic therapies.
Since the advent of highly effective TNF-α inhibitors for treating spondyloarthritis that is urgent to find sensitive methods for detecting inflammatory changes not only of the sacroiliac joints but also of the entire spine.