Reactive Arthritis (Campylobacter jejuni)

Overview


Plain-Language Overview

Reactive Arthritis (ReA) is a condition that causes inflammation primarily in the joints, often following an infection in the digestive or urinary tract. It mainly affects the musculoskeletal system, leading to symptoms like joint pain, swelling, and stiffness. This condition typically develops a few weeks after an infection with bacteria such as Campylobacter jejuni, which causes intestinal illness. Besides joints, it can also affect the eyes, skin, and urinary tract, causing redness, rashes, or painful urination. The inflammation results from the immune system reacting abnormally to the infection, even though the bacteria are no longer present in the joints. This immune response can cause discomfort and limit movement, impacting daily activities.

Clinical Definition

Reactive Arthritis (ReA) is a sterile inflammatory arthritis triggered by a preceding infection, most commonly involving the gastrointestinal or genitourinary tract. It is characterized by an autoimmune response to bacterial antigens, particularly from Campylobacter jejuni, leading to synovial inflammation without direct joint infection. The pathogenesis involves molecular mimicry and immune complex deposition, often in genetically predisposed individuals carrying the HLA-B27 allele. Clinically, ReA presents with asymmetric oligoarthritis predominantly affecting the lower limbs, enthesitis, and extra-articular manifestations such as conjunctivitis and urethritis. The condition is part of the seronegative spondyloarthropathies group and can cause significant morbidity due to joint pain and systemic symptoms. Diagnosis relies on clinical history, evidence of recent infection, and exclusion of other causes of arthritis.

Inciting Event

  • Acute gastroenteritis caused by Campylobacter jejuni infection is the typical trigger.

  • Other enteric infections such as Salmonella and Shigella can also precipitate reactive arthritis.

  • Genitourinary infections with Chlamydia trachomatis may trigger a similar syndrome.

Latency Period

  • Symptoms typically develop 1 to 4 weeks after the initial enteric infection.

  • Latency allows for immune sensitization and development of autoimmune joint inflammation.

  • Delayed onset can complicate linking arthritis to the preceding infection.

Diagnostic Delay

  • Lack of awareness of the association between gastroenteritis and arthritis leads to missed diagnosis.

  • Initial symptoms may be attributed to viral arthritis or septic arthritis, delaying correct diagnosis.

  • Absence of positive synovial fluid cultures can mislead clinicians away from reactive arthritis.

Clinical Presentation


Signs & Symptoms

  • Acute asymmetric arthritis developing 1-4 weeks after Campylobacter jejuni enteric infection

  • Conjunctivitis or painful red eyes often accompanying joint symptoms

  • Urethritis or dysuria in males as part of the classic triad

  • Enthesitis causing localized pain at tendon insertions

  • Low back pain due to sacroiliac joint involvement

  • Fever and malaise may be present during the acute phase

History of Present Illness

  • Patients report acute onset of asymmetric oligoarthritis, predominantly affecting lower limb joints.

  • Preceding diarrheal illness with abdominal cramps and fever is common.

  • Additional symptoms include enthesitis, conjunctivitis, and urethritis, forming the classic triad.

  • Arthritis symptoms often wax and wane over weeks to months.

Past Medical History

  • Recent history of gastrointestinal infection with symptoms of diarrhea and abdominal pain.

  • Prior episodes of reactive arthritis or other spondyloarthropathies increase recurrence risk.

  • No history of chronic inflammatory arthritis such as rheumatoid arthritis or lupus.

Family History

  • Family history of spondyloarthropathies such as ankylosing spondylitis or reactive arthritis is common.

  • HLA-B27-associated diseases may cluster in families, increasing genetic predisposition.

  • No direct inheritance pattern but increased risk in first-degree relatives with autoimmune arthritis.

Physical Exam Findings

  • Asymmetric oligoarthritis predominantly affecting the lower extremities, especially knees and ankles

  • Enthesitis at tendon insertions such as the Achilles tendon and plantar fascia

  • Conjunctivitis or anterior uveitis with eye redness and pain

  • Dactylitis causing sausage-shaped digits

  • Mucocutaneous lesions including keratoderma blennorrhagicum and circinate balanitis

Diagnostic Workup


Diagnostic Criteria

Diagnosis of reactive arthritis is based on a combination of clinical features including asymmetric oligoarthritis, typically involving the lower extremities, and a history of recent gastrointestinal or genitourinary infection, such as with Campylobacter jejuni. Laboratory tests may show elevated inflammatory markers but negative synovial fluid cultures, confirming sterile joint inflammation. Detection of HLA-B27 supports the diagnosis but is not required. Confirmation involves ruling out other causes of arthritis and identifying evidence of preceding infection through stool cultures or serology. Imaging may reveal characteristic enthesitis or sacroiliitis.

Pathophysiology


Key Mechanisms

  • Molecular mimicry between Campylobacter jejuni antigens and host joint tissues triggers autoimmune inflammation.

  • HLA-B27-associated immune dysregulation promotes aberrant T-cell activation and chronic synovitis.

  • Post-infectious immune complex deposition in synovial membranes contributes to joint inflammation.

  • Cytokine-mediated inflammation involving TNF-alpha and IL-17 drives enthesitis and arthritis.

InvolvementDetails
Organs

Joints are the main organs affected, presenting with asymmetric oligoarthritis.

Eyes may be involved causing conjunctivitis or anterior uveitis as extra-articular manifestations.

Tissues

Synovial membrane is the primary site of inflammation causing joint swelling and pain.

Entheses (sites of tendon and ligament insertion) are commonly inflamed leading to enthesitis.

Cells

CD4+ T cells mediate the autoimmune inflammatory response in reactive arthritis.

Macrophages produce proinflammatory cytokines contributing to joint inflammation.

Neutrophils infiltrate synovial fluid causing acute inflammation and tissue damage.

Chemical Mediators

Tumor necrosis factor-alpha (TNF-α) is a key cytokine driving synovial inflammation and joint damage.

Interleukin-17 (IL-17) promotes neutrophil recruitment and sustains chronic inflammation.

Prostaglandins mediate pain and swelling in affected joints.

Treatments


Pharmacological Treatments

  • NSAIDs

    • Mechanism:
      • Inhibit cyclooxygenase enzymes to reduce prostaglandin synthesis and decrease inflammation.

    • Side effects:
      • Gastrointestinal bleeding

      • Renal impairment

      • Hypertension

    • Clinical role:
      • First-line

  • Sulfasalazine

    • Mechanism:
      • Modulates immune response by inhibiting inflammatory cytokines and suppressing T-cell proliferation.

    • Side effects:
      • Rash

      • Leukopenia

      • Hepatotoxicity

    • Clinical role:
      • Second-line

  • Corticosteroids

    • Mechanism:
      • Suppress multiple inflammatory pathways by inhibiting cytokine production and immune cell activation.

    • Side effects:
      • Hyperglycemia

      • Osteoporosis

      • Immunosuppression

    • Clinical role:
      • Adjunctive

  • Antibiotics (e.g., macrolides or fluoroquinolones)

    • Mechanism:
      • Target Campylobacter jejuni to eradicate persistent infection triggering reactive arthritis.

    • Side effects:
      • Gastrointestinal upset

      • Tendonitis

      • QT prolongation

    • Clinical role:
      • Supportive

Non-pharmacological Treatments

  • Physical therapy to maintain joint mobility and reduce stiffness.

  • Rest and joint protection during acute inflammatory episodes.

  • Patient education on avoiding triggers and managing symptoms.

Prevention


Pharmacological Prevention

  • No established antibiotic prophylaxis to prevent reactive arthritis after Campylobacter jejuni infection

  • Early antibiotic treatment of enteric infection may reduce risk but is not definitively preventive

  • NSAIDs used to control inflammation and may reduce progression if started early

Non-pharmacological Prevention

  • Proper food handling and cooking to prevent Campylobacter jejuni infection

  • Hand hygiene after contact with potentially contaminated sources

  • Avoidance of unpasteurized dairy and contaminated water to reduce exposure risk

  • Prompt treatment of enteric infections to minimize immune-mediated sequelae

Outcome & Complications


Complications

  • Chronic arthritis leading to joint damage and deformity in a minority of patients

  • Recurrent uveitis causing vision impairment if untreated

  • Enthesopathy resulting in chronic tendon pain and dysfunction

  • Secondary amyloidosis is a rare complication from prolonged inflammation

Short-term Sequelae Long-term Sequelae
  • Acute asymmetric oligoarthritis causing joint swelling and pain

  • Conjunctivitis or anterior uveitis with eye discomfort

  • Urethritis or cervicitis presenting with dysuria or discharge

  • Systemic symptoms such as fever and fatigue during the initial weeks

  • Chronic spondyloarthritis with persistent joint inflammation and stiffness

  • Sacroiliitis leading to chronic low back pain and reduced mobility

  • Recurrent episodes of arthritis and uveitis over months to years

  • Permanent joint deformities in severe or untreated cases

Differential Diagnoses


Reactive Arthritis (Campylobacter jejuni) versus Ankylosing Spondylitis

Reactive Arthritis (Campylobacter jejuni)

Ankylosing Spondylitis

Usually occurs after a gastrointestinal infection, often in young adults

Typically presents in late adolescence to early adulthood (ages 15-30)

May be associated with HLA-B27, but less consistently

Strong association with HLA-B27 positivity

Acute or subacute arthritis following infection, often self-limited

Chronic progressive axial skeleton involvement with sacroiliitis

Reactive Arthritis (Campylobacter jejuni) versus Psoriatic Arthritis

Reactive Arthritis (Campylobacter jejuni)

Psoriatic Arthritis

Preceding gastrointestinal infection such as Campylobacter jejuni

History of psoriasis or psoriatic skin lesions

Seronegative arthritis with elevated acute phase reactants post-infection

Usually RF-negative but may have elevated inflammatory markers

Asymmetric oligoarthritis without erosive changes typical of psoriatic arthritis

Asymmetric oligoarthritis with pencil-in-cup deformities on X-ray

Reactive Arthritis (Campylobacter jejuni) versus Rheumatoid Arthritis

Reactive Arthritis (Campylobacter jejuni)

Rheumatoid Arthritis

Seronegative arthritis without RF or anti-CCP antibodies

Positive rheumatoid factor (RF) and anti-CCP antibodies

Asymmetric oligoarthritis often involving large joints after infection

Chronic symmetric polyarthritis primarily affecting small joints

No erosive changes early in disease; imaging often normal or shows soft tissue swelling

Joint space narrowing and marginal erosions on X-ray

Reactive Arthritis (Campylobacter jejuni) versus Post-Streptococcal Reactive Arthritis

Reactive Arthritis (Campylobacter jejuni)

Post-Streptococcal Reactive Arthritis

Recent gastrointestinal infection with Campylobacter jejuni

Recent streptococcal pharyngitis or skin infection

Arthritis develops 1-4 weeks after enteric infection

Arthritis develops within 2-3 weeks after streptococcal infection

Negative ASO titers; diagnosis supported by stool culture or serology for Campylobacter

May have elevated ASO titers indicating recent streptococcal infection

Reactive Arthritis (Campylobacter jejuni) versus Inflammatory Bowel Disease-associated Arthritis

Reactive Arthritis (Campylobacter jejuni)

Inflammatory Bowel Disease-associated Arthritis

No underlying chronic inflammatory bowel disease; arthritis follows infection

History of Crohn disease or ulcerative colitis

Arthritis occurs after enteric infection independent of chronic bowel symptoms

Arthritis often parallels bowel disease activity

Elevated acute phase reactants but no chronic anemia or bowel inflammation markers

Elevated inflammatory markers with possible anemia of chronic disease

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