Ankylosing Spondylitis: Key Features

Ankylosing Spondylitis (AS) is a chronic inflammatory seronegative spondyloarthropathy that primarily affects the sacroiliac joints and axial skeleton. The correct answer is 1, 3 and 4.

Statement Analysis

• Statement 1: Bamboo spine may be seen — Correct. In advanced/late-stage disease, progressive syndesmophyte formation with ossification of the annulus fibrosus and paravertebral ligaments fuses adjacent vertebrae, producing the classic "bamboo spine" appearance on spinal X-ray.
• Statement 2: Early morning back pain is rare — Incorrect. Inflammatory back pain is a hallmark of AS, and it characteristically presents with prominent early morning stiffness and pain that improves with activity/exercise and worsens with rest — the opposite of what this statement claims. Early morning back pain is common, not rare, in AS.
• Statement 3: Uveitis is the most common extra-articular feature — Correct. Acute anterior uveitis (iritis) is the most frequent extra-articular manifestation of Ankylosing Spondylitis, occurring in roughly 25–40% of patients, often as recurrent, unilateral, painful red eye episodes. It is more common than cardiac (aortic regurgitation, conduction defects) or pulmonary (apical fibrosis) involvement.
• Statement 4: It is more common in males — Correct. AS shows a strong male predominance, with a male-to-female ratio classically cited around 3:1 (though milder/atypical disease is increasingly recognized in females).

Conclusion

Statements 1, 3, and 4 are true, while statement 2 is false because morning back stiffness/pain is a defining and common feature of AS rather than a rare one. Hence, the correct option is "1, 3 and 4".