Performance of referral recommendations in patients with chronic back pain and suspected axial spondyloarthritis.
BACKGROUND
Ankylosing spondylitis (AS) and its early form account for up to 5% of all patients with chronic back pain. Interest has recently focused on shortening the delay of 5-10 years between the appearance of first symptoms and the diagnosis of AS, particularly because effective treatments have now become available. Referral parameters that are easy for doctors in primary care to apply to patients presenting with possible AS could contribute to earlier diagnosis.


METHODS
Orthopaedists and primary-care doctors were requested to refer patients with (1) chronic low back pain (duration >3 months) and (2) onset of back pain before <45 years of age to a specialist rheumatology outpatient clinic for further diagnostic investigation if at least one of the following screening parameters was present: (1) inflammatory back pain, (2) positive human leucocyte antigen B27, and (3) sacroiliitis detected by imaging. The final diagnosis was made according to expert opinion.


RESULTS
In total, 350 referred cases were analysed. A diagnosis of definite axial spondyloarthritis (axial SpA), comprising established AS and pre-radiographic axial SpA, could be made in 45.4% of all referred patients (of which 50.3% were classified as AS and 49.7% as preradiographic axial SpA), whereas 45.4% were classified as non-SpA and 9.1% as possible SpA. A diagnosis of definite axial SpA could be made in 34.2% if only one referral parameter was positive, and in 62.6% if there was >1 positive referral parameter.


CONCLUSIONS
The proposed referral parameters have proven useful when applied in primary care in identifying patients with AS/pre-radiographic axial SpA among young to middle-aged patients with chronic low back pain.
Brandt
Henning Christian
HC
Rheumatology, Department of Medicine I, Charité Campus Benjamin Franklin, Berlin, Germany.
Spiller
Inge
I
Song
In-Ho
IH
Vahldiek
Janis L
JL
Rudwaleit
Martin
M
Sieper
Joachim
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D001368:Axis, Cervical Vertebra; D015415:Biomarkers / Q000032:analysis; D002908:Chronic Disease; D042241:Early Diagnosis; D005260:Female; D005858:Germany; D015796:HLA-B27 Antigen / Q000032:analysis; D006801:Humans; D017116:Low Back Pain / Q000209:etiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D010044:Outpatient Clinics, Hospital; D018579:Patient Selection; D011320:Primary Health Care / Q000379:methods / Q000592:standards; D012017:Referral and Consultation / Q000592:standards*; D025241:Spondylarthritis / Q000150:complications / Q000175:diagnosis*; D013167:Spondylitis, Ankylosing / Q000150:complications / Q000175:diagnosis; D013997:Time Factors
D015415:Biomarkers; D015796:HLA-B27 Antigen