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What is A 65-yr-old man with H/O back pain since 3 months. ESR is raised. On examination marked stiffness and mild restriction of chest movements is found. On x-ray, syndesmophytes are present in vertebrae. Diagnosis is - and explain in detail?
The clinical profile of the given case fits into Ankylosing spondylitis (A.S.) except for the age.
A.S. is usually seen in 2nd or 3rd decades of age with a median age of 23. However "in 5% ofpatients, symptoms begin after 40" - Harrison
All other features, i.e. raised ESR, marked stiffness, restriction of chest movements & syndesmophytes are seen in A.S.