Validity of magnetic resonance image and HLA-B27 in early detection of sacroiliitis in Egyptian spondyloarthropathic patients

الملخص EN

Objective The aim of this study was to compare the validity of MRI in the early detection of sacroiliitis with laboratory findings of human leukocyte antigen-B27 (HLA-B27), conventional radiography, and clinical assessment.

Participants and methods Sixty patients with spondyloarthropathy (group II) with duration of illness less than 2 years and 20 healthy controls (group I) were included in this study.

Both groups were subjected to assessment of history, clinical examination, and laboratory investigations (erythrocyte sedimentation rate, C-reactive protein titer, rheumatoid factor, HLA-B27).

Conventional radiography and MRI of the sacroiliac joints were performed.

Spondyloarthropathic patients were divided according to MRI as follows: group IIA, which included patients with sacroiliitis, and group IIB, which included patients without sacroiliitis.

Results In our study, ankylosing spondylitis was diagnosed in 22 (36.6%) patients, followed by undifferentiated spondyloarthropathy in 12 (20%) patients, reactive arthritis in 10 (16.7%) patients, psoriatic arthropathy in 10 (16.7%) patients, and enteropathic arthropathy in six (10%) patients.

Evidence of sacroiliitis was found in 66.6% (40/60) of patients by MRI, which was higher than the result obtained by plain radiography 20% (12/60).

HLA-B27 positivity found in 53.3% (32/60) of patients.

There was a significant difference between the two groups in HLA-B27 and radiological sacroiliitis; there was no sacroiliitis in the control group.

MRI showed sacroiliitis even in patients with no inflammatory back pain.

There was a highly statistically significant difference between patient subgroups in disease duration (P = 0.001) and primary complaints and clinical sacroiliitis (P = 0.001).

Conclusion MRI is the preferred modality in the detection of early sacroiliitis in spondyloarthropathy and HLA-B27 positivity is a highly useful predictor of early sacroiliitis