Summary
Definition
History and exam
Key diagnostic factors
- HLA-B27 positive
- inflammatory back pain
- iritis/uveitis
- enthesitis
- presentation in late teens and early 20s
- male sex
- positive family history of AS
Other diagnostic factors
- fatigue
- sleep disturbance
- tenderness at sacroiliac joint
- dyspnea
- loss of lumbar lordosis
- peripheral joint involvement
- kyphosis
- psoriasis
- symptoms of inflammatory bowel disease
Risk factors
- HLA-B27
- endoplasmic reticulum aminopeptidase 1 (ERAP1) and interleukin-23 receptor (IL23R) genes
- positive family history of AS
- male sex
- Klebsiella pneumoniae
Diagnostic investigations
1st investigations to order
- pelvic x-ray
Investigations to consider
- HLA-B27
- MRI
- cervical spine x-ray (lateral)
- lumbar spine x-ray (lateral)
- thoracic spine x-ray (lateral)
- ultrasound
Treatment algorithm
adults with pain and/or stiffness
adults without pain and/or stiffness
children
adults with pain and/or stiffness refractory to 2 NSAIDs and nonpharmacologic measures
Contributors
Authors
Antoni Chan, MBChB, FRCP, PhD
Consultant
Rheumatology Department
Royal Berkshire NHS Foundation Trust
Reading
UK
Disclosures
AC has served on the advisory boards for MSD, Novartis, and Sanofi; contributed to educational events for Janssen, MSD, Novartis, Sanofi, and Celgene; been on the speaker bureau for Janssen, Pfizer, and Novartis; and received travel grants from AbbVie, UCB, Lilly, and Pfizer to attend educational conferences.
Sarah Sacks, MBBS, BSc
Specialist Registrar in Rheumatology
Stoke Mandeville Hospital
Aylesbury
UK
Disclosures
SS declares that she has no competing interests.
Acknowledgements
Dr Antoni Chan and Dr Sarah Sacks would like to gratefully acknowledge Dr Jessica Gunn, Dr Sarah Keidel, Dr Millicent Stone, Dr Raj Sengupta, Dr Athimalaipet V. Ramanan, and Dr Emma Pomeroy, the previous contributors to this topic.
Disclosures
JG, SK, RS, and AVR declare that they have no competing interests. MS is an author of several references cited in this topic. EP is an author of a reference cited in this topic.
Peer reviewers
Roger Sturrock, MD, FRCP
Professor of Rheumatology
Centre for Rheumatic Diseases
University Department of Medicine
Glasgow Royal Infirmary University Trust
Glasgow
UK
Disclosures
RS is an author of a reference cited in this topic.
Andrew Keat, MBBS
Consultant Physician and Rheumatologist
Northwick Park Hospital
Harrow
UK
Disclosures
AK declares that he has no competing interests.
Karl Gaffney, BCh, BAO (Hons), FRCPI, FRCP
Consultant
Norfolk and Norwich University Hospital
Norwich and the Cromer & District Hospital
Cromer
UK
Disclosures
KG is an author of a reference cited in this topic.
Alexios G. Carayannopoulos, DO, MPH
Interventional Spine Physiatrist
Pain Medicine Specialist
Medical Director
Spine Center
Lahey Clinic
Burlington
MA
Disclosures
AGC declares that he has no competing interests.
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