Reactive arthritis

Reactive arthritis (ReA) is a sterile inflammatory arthritis that follows an infection at a different site, commonly enteric or urogenital. It is classified as a type of seronegative spondyloarthropathy.

Reactive arthritis was formerly known as Reiter syndrome/disease, which is the combination of urethritis, arthritis and conjunctivitis. Not all patients with reactive arthritis have Reiter syndrome (also see History and etymology). 

Reactive arthritis most commonly occurs in males between ages 15-35 2. It has an incidence of ~1 in 100 following enteric infections. 

Usually transient following infection and involving one or two large joints. The classical triad consists of:

  • arthritis
  • conjunctivitis
  • urethritis (cervicitis in women) 

The following mnemonic can be used to remember the classical triad encountered in reactive arthritis: "Can't see, can't pee, can't climb a tree''.

Other extra-articular manifestations include cardiac conduction abnormalities and aortic regurgitation. 

In reactive arthritis there is joint inflammation, bone proliferation, periostitis, and enthesitis.

Aetiology

Reactive arthritis occurs following infections including 5-8:

  • enteric: Yersinia, Salmonella, Shigella, Campylobacter and less commonly enterotoxic Escherichia coli (ETEC)
  • sexually-transmitted: Chlamydia trachomatis
  • other: brucellosis
Markers
  • HLA B27 positive in ~80% of patients

Distal lower extremity involvement (metatarsophalangeal joints >> calcaneus > ankle > knee) is more prevalent than upper extremity involvement. It affects hands, wrists, and feet with a distribution that is unilateral or bilateral and asymmetric (it becomes symmetric in later stages).

It can have a very similar appearance to psoriatic arthritis with the classic features of ill-defined erosions, enthesopathy, bone proliferation, early juxta-articular osteoporosis, uniform joint space loss and fusiform soft tissue swelling 2.  

Both psoriasis and reactive arthritis can cause a sacroiliitis, which is usually asymmetric 3.

The disease was originally named after Hans Reiter. However, recently this term has not been encouraged as he was a convicted Nazi war criminal who performed experiments of a new typhus vaccine that caused the death of hundreds of prisoners of war 9.

  • tends to resolve after a few months in half of patients
  • remaining patients have recurrent arthritis, tendinitis and fasciitis
  • psoriatic arthritis
    • reactive arthritis has a different distribution; hand involvement is very uncommon, while common in psoriatic arthritis 2
    • spondyloarthropathy and sacroiliitis appear identical in both conditions
  • disseminated gonococcal infection 
    • causes septic arthritis, cf. sterile process of reactive arthritis
Arthritides
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Article information

rID: 25753
Section: Syndromes
Tag: cases
Synonyms or Alternate Spellings:
  • Reiter's Disease
  • Reiter Disease
  • Reiter's syndrome
  • Reiter syndrome
  • Reactive arthritis (ReA)

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