Ankylosing spondylitis

Question 1

Ankylosing spondylitis

Answer 1

HLA-B27 associated spondyloarthropathy

Male:female 3:1

Typically aged 20-30 years old

Question 2

Investigations

Answer 2

ESR/ CRP typically raised

90% have HLA-B27

Plain xray of sacroiliac joints is most useful investigation

Question 3

Xray findings

Answer 3

Sacroiliitis: subchondral erosions, sclerosis

Squaring of lumbar vertebrae

‘Bamboo spine’ (late and uncommon)

Syndesmophytes: due to ossification of outer fibres of annulus fibrosis

Chest xray: apical fibrosis

Question 4

Conservative management

Answer 4

Encourage regular exercise

Physiotherapy

Question 5

Medical management

Answer 5

NSAIDs first line

DMARDs if peripheral joint involvement

Anti-TNF therapy if persistently high disease activity despite conventional treatments