Imaging of suspected spondyloarthropathy: practice within the North Midlands compared to EULAR.
Morjaria, A; Sabir, Y; Datta, P.
Background - Spondyloarthropathy (SpA) is an inflammatory disease that affects 1-2% of the population within the UK. These diseases are characterised by their association with the gene HLA-B27 and presence of enthesitis.
•First line investigation are XR’s of the sacro-iliac joint’s (SIJ’s)
•MRI is recommended if the patient is young or there has been a short clinical duration
• MRI should be used to monitor the inflammatory activity in terms of clinical response in SpA.
•XR’s of the SIJ can be used in long-term monitoring of structural damage and should be repeated every 2 years.
1.To determine if XR’s of the SIJ’s are the 1st line imaging request for detecting SpA in the North Midlands.
2.Are referrals to the radiology department for SpA appropriate for justification?
3. Are we detecting SpA on MRI according to the To target?
: Rudwaleit et al demonstrated that the SpA detection rate should be 80-95%, if all other factors are positive e.g X-rays, HLA-B27 and clinical history without the need for MRI.
•6 months worth of retrospective data collected from 1st July-31st December 2014.
•CRIS reporting system used to identify MRI scans of SIJ’s using code MSIJS which gave a sample size of 163.
•A database was created with patient demographics, referrer speciality, whether SpA was detected, not detected or equivocal.
•The scans were divided into ‘direct’ where the scan was for the exclusion of SpA. The alternatives were ‘indirect’ where symptoms of inflammatory back pain were described, however SpA was not mentioned and ‘exclusion’ where SpA is not the diagnosis in question.
Results: 83% of referrals were from rheumatologists, from which only 40% were direct. Only 46% (71) had SIJ X-rays prior to their MRI, of which 30% (21) were positive. Furthermore, the detection rate for SpA through MRI was only 10% (16).
First action plan:
1.SIJ XR’s should be reported before an MRI is requested.
2.Referrals for SpA should be direct.
3.Protocol in rheumatology clinic rooms /Trust intranet to assist imaging referrals.
4.Re-audit in 6 months.
:Direct requests from rheumatologists increased to 64% and prior SIJ XR’s had risen to 71%. The detection rate of SpA on MRI slightly increased to 14%, demonstrating an overall improvement.
SpA detection on MRI was poor, even though direct requests and prior SIJ XR’s had increased. Therefore, MRI’s should only be requested if stated in the XR report to reduce negative MRI scans.
1. Sheehan NJ. The ramifications of HLA-B27. Journal of the Royal Society of Medicine. 2004;97(1):10-4
2. Mandl P et al. EULAR recommendations for the use of imaging in the diagnosis and management of spondyloarthritis in clinical practice. Ann Rheum Disease. 2015;74:1327-1339.
3. Rudwaleit M et al. How to diagnose axial spondyloarthritis early. Ann Rheum Disease. 2004;63(5):535-43