Reactive arthritis

Question 1

state the typical presentation of reactive arthritis?

Answer 1

CANT SEE (conjunctivitis) CANT PEE (urethritis) CANT CLIMB A TREE (arthritis - lower limbs and spondylitis + enthesitis) - GU/GI infection (fever, malaise), skin lesions such as circinate balanitis and keratoderma blennorrhagica

Question 2

define reactive arthritis?

Answer 2

Characterised by a sterile arthritis occurring after an extra-articular infection(commonly GI or urogenital).

Typically affects lower limbs 1-4 weeks after urethritis or dysentery

Type of spondyloarthritides (negative autoantibodies!)

Question 3

what is reactive arthritis a triad of?

Answer 3

Reiter’s Syndrome is defined as a TRIAD of:

• Reactive arthritis
• Urethritis
• Conjunctivitis

Question 4

which infections is reactive arthritis associated with?

Answer 4

GI

• Salmonella
• Shigella
• Yersinia
• Campylobacter

Urogenital

• Chlamydia trachomatis (60%)
• Ureaplasma species

Question 5

outline the aetiology of reactive arthritis?

Answer 5

Associated with infections: GI and urogenital

It is thought that initial activation of the immune system by a microbial antigen is followed by an autoimmune reaction that involves the skin, eyes and joints

HLA-B27 allele is identified in 70-80% of patients

Question 6

Which allele is associated with reactive arthritis?

Answer 6

HLA-B27

Question 7

summarise the epidemiology of reactive arthritis?

Answer 7

20 x more common in MALES

Age of onset: 20-40 yrs

Seen in 2% of patients with non-specific urethritis

Question 8

what are the presenting symptoms of reactive arthritis?

Answer 8

Symptoms can develop 3-30 days after infection

Burning or stinging when passing urine (due to urethritis)

Arthritis – clinical symptoms present within 1 – 4 weeks after onset of infection

Low back pain (due to sacroiliitis) - relieved by exercise (distinguishes it from mechanical causes of back pain)

Painful heels (due to enthesitis and plantar fasciitis)

• Enthesis is where tendons insert into bones

Conjunctivitis

Fever, fatigue and weight loss are common

Question 9

what are the classes of signs of reactive arthritis on physical examination?

Answer 9

ABCD

Signs of Arthritis

Circinate Balanitis

Signs of Conjunctivitis

Keratoderma Blenorrhagica

Question 10

what are the signs of arthritis

Answer 10

Asymmetrical oligoarthritis

Often affects the lower extremities

Sausage-shaped digits

Painful, swollen, red, warm and stiff – esp in the mornings

Axial arthritis esp of sacroiliac joints and lumbosacral spine is common

Question 11

what are the signs conjuctivitis?

Answer 11

Anterior uveitis - painful red eye and photophobia

Question 12

what is circinate balantis?

Answer 12

Scaling red patches on the glans

Painless

Question 13

what is Keratoderma Blenorrhagica

Answer 13

Brownish-red macules

Vesicopustules

Yellowish-brown scales

Found on the SOLES and PALMS

Question 14

what are the other signs of reactive arthritis?

Answer 14

Nail dystrophy

Hyperkeratosis

Onycholysis

Mouth ulcers

Question 15

what are the appropriate investigations for reactive arthritis and interpret the results

Answer 15

Bloods

• FBC
• High ESR and CRP
• HLA-B27 testing

Stool or Urethral Swabs and Cultures

• May be negative by the time the arthritis develops (because the arthritis occurs post-infection)

Urine- Screen for Chlamydia trachomatis

Plain X-Rays

• Useful in chronic cases
• Erosions seen at the entheses (insertion of tendons into bone)
• Sacroilitis

Joint Aspiration- exclude septic or crystal arthritis

Question 16

what are the differences between rheumatoid arthritis and reactive arthritis?

Answer 16