Reiter's Syndrome (Reactive Arthritis): Symptoms, Causes & Treatment

Reiter’s syndrome, now called reactive arthritis, is inflammatory arthritis triggered by bacterial infections (often in the gut or genitourinary tract). It typically causes joint pain, eye inflammation, and urinary symptoms. Diagnosis relies on history and exams; treatment includes NSAIDs, antibiotics if active infection exists, and sometimes DMARDs or biologics. Most recover within a year, but early treatment improves outcomes.

Reiter’s syndrome, historically known as Reiter’s disease, is a form of inflammatory arthritis that develops after certain bacterial infections. Today, the preferred medical term is reactive arthritis, as it more accurately describes the condition and avoids the eponym associated with Hans Reiter.

Reactive arthritis typically affects the joints, eyes, skin, and genitourinary tract. It is characterized by sterile joint inflammation occurring after an infection elsewhere in the body, most commonly within the gastrointestinal or genitourinary system.

Understanding reiter’s syndrome is important because early recognition and treatment can reduce symptoms, prevent complications, and improve long-term outcomes.

What is Reiter’s Syndrome?

Reiter’s syndrome is a subtype of seronegative spondyloarthritis characterized by inflammatory arthritis triggered by a preceding infection.

Traditionally, the condition was described by the triad of:

Arthritis
Urethritis
Conjunctivitis

However, many patients do not develop all three manifestations simultaneously.

The syndrome usually appears one to four weeks after an infection and most commonly affects young adults between 20 and 40 years of age.

Historical Background

The term Reiter’s disease originated from German physician Hans Reiter, who described the syndrome in the early 20th century. Modern medical literature now favors the term reactive arthritis because it more accurately reflects the underlying pathophysiology.

Although the name reiter’s syndrome is still widely recognized in educational materials and patient discussions, healthcare professionals increasingly use “reactive arthritis.”

Causes of Reiter’s Syndrome

Reactive arthritis develops after an infection triggers an abnormal immune response.

Common Triggering Bacterial Infections

Genitourinary Infections

Chlamydia trachomatis
Ureaplasma urealyticum

Gastrointestinal Infections

Salmonella species
Shigella species
Campylobacter jejuni
Yersinia enterocolitica
Clostridioides difficile (less common)

The triggering infection may have resolved by the time joint symptoms appear.

Pathophysiology

The exact mechanism remains incompletely understood.

Current evidence suggests that bacterial antigens persist within tissues and stimulate an immune-mediated inflammatory response. Genetic susceptibility also plays an important role.

Role of HLA-B27

Approximately 50% to 80% of patients with reactive arthritis are positive for the HLA-B27 gene.

HLA-B27 positivity is associated with:

More severe disease
Increased risk of chronic symptoms
Greater likelihood of axial involvement
Higher recurrence rates

See Also: Juvenile Rheumatoid Arthritis: Symptoms, Treatment & Prognosis

Epidemiology

Reactive arthritis occurs worldwide.

Key epidemiological features include:

More common in males
Typically affects individuals aged 20–40 years
Frequently follows sexually transmitted or enteric infections
Higher prevalence among HLA-B27-positive populations

Reiter's Syndrome (Reactive Arthritis) Symptoms, Causes, Diagnosis, and Treatment

Symptoms of Reiter’s Syndrome

Symptoms usually begin several weeks after the triggering infection.

Articular Manifestations

Joint involvement is often asymmetric and affects the lower extremities.

Common features include:

Knee pain and swelling
Ankle arthritis
Foot pain
Hip involvement
Sacroiliac joint inflammation

Patients may experience:

Morning stiffness
Reduced mobility
Joint tenderness
Warmth around affected joints

Enthesitis

Inflammation where tendons attach to bone is common.

Typical sites include:

Achilles tendon
Plantar fascia
Patellar tendon

Dactylitis

Diffuse swelling of an entire finger or toe may occur, producing the characteristic “sausage digit” appearance.

Extra-Articular Manifestations

Ocular Involvement

Eye symptoms may include:

Conjunctivitis
Anterior uveitis
Eye redness
Photophobia
Blurred vision

Genitourinary Symptoms

Patients may develop:

Urethritis
Dysuria
Prostatitis in men
Cervicitis in women

Skin Manifestations

Common dermatological findings include:

Keratoderma Blennorrhagica

Hyperkeratotic skin lesions usually affecting:

Soles
Palms

Circinate Balanitis

Painless inflammatory lesions involving the glans penis.

Oral Lesions

Some patients develop:

Oral ulcers
Tongue lesions

Diagnosis of Reiter’s Syndrome

No single laboratory test confirms the diagnosis.

Diagnosis is based on:

Clinical findings
History of preceding infection
Laboratory investigations
Imaging studies

Medical History

Clinicians should inquire about:

Recent diarrhea
Foodborne illness
Sexually transmitted infections
Previous episodes of arthritis

Physical Examination

Assessment includes:

Joint swelling
Enthesitis
Eye inflammation
Skin lesions
Genitourinary abnormalities

Laboratory Investigations

Blood Tests

Common findings include:

Elevated ESR
Elevated C-reactive protein (CRP)
Mild anemia of chronic disease

HLA-B27 Testing

Useful for prognostic assessment but not required for diagnosis.

Microbiological Testing

Tests may include:

Urine nucleic acid amplification tests (NAATs)
Stool cultures
Chlamydia testing

Synovial Fluid Analysis

Joint aspiration helps exclude:

Septic arthritis
Crystal arthropathy

Typically, synovial fluid demonstrates inflammatory changes without bacterial growth.

Imaging Studies

Plain Radiographs

May reveal:

Soft tissue swelling
Periostitis
Joint space narrowing in chronic disease

Ultrasound

Useful for evaluating:

Synovitis
Enthesitis
Tendon involvement

MRI

Provides detailed visualization of:

Sacroiliitis
Bone marrow edema
Early inflammatory changes

Differential Diagnosis

Conditions that may mimic reiter’s syndrome include:

Septic arthritis
Rheumatoid arthritis
Psoriatic arthritis
Ankylosing spondylitis
Gout
Inflammatory bowel disease-associated arthritis
Lyme disease

Reiter’s Syndrome Treatment

Treatment focuses on controlling inflammation, eradicating active infection, and preserving function.

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)

NSAIDs are first-line therapy.

Examples include:

Ibuprofen
Naproxen
Diclofenac
Indomethacin

These medications help reduce:

Pain
Stiffness
Joint swelling

Antibiotic Therapy

Antibiotics are indicated when an active infection is identified.

For Chlamydia-associated disease, treatment may include:

Doxycycline
Azithromycin

Routine prolonged antibiotic therapy is not recommended for all patients.

Corticosteroids

Intra-Articular Corticosteroid Injections

Useful for:

Persistent monoarthritis
Oligoarthritis

Systemic Corticosteroids

Reserved for severe cases with extensive inflammation.

Disease-Modifying Antirheumatic Drugs (DMARDs)

Patients with chronic disease may benefit from:

Sulfasalazine
Methotrexate

Biologic Therapy

For refractory cases, biologic agents may be considered.

Examples include:

TNF inhibitors
IL-17 inhibitors

These treatments are generally managed by rheumatology specialists.

Physical Therapy and Rehabilitation

Physical therapy plays a vital role in recovery.

Benefits include:

Maintaining joint mobility
Improving muscle strength
Preventing contractures
Enhancing function

Recommended activities may include:

Stretching exercises
Range-of-motion exercises
Low-impact aerobic training

Complications

Potential complications include:

Chronic arthritis
Recurrent disease episodes
Sacroiliitis
Persistent enthesitis
Vision-threatening uveitis
Reduced quality of life

Prognosis

The prognosis of Reiter’s disease is generally favorable.

Most patients experience improvement within:

3 to 12 months

However, some develop:

Chronic arthritis
Recurrent symptoms
Progressive spondyloarthritis

Poor prognostic factors include:

HLA-B27 positivity
Severe initial disease
Axial involvement
Recurrent infections

Prevention

Preventive measures focus on reducing infection risk.

Recommendations include:

Practicing safe sex
Prompt treatment of sexually transmitted infections
Proper food hygiene
Handwashing
Early medical evaluation after gastrointestinal infections

Key Points

Reiter’s syndrome is now more commonly called reactive arthritis.
It develops after gastrointestinal or genitourinary infections.
Arthritis, conjunctivitis, and urethritis form the classic clinical triad.
HLA-B27 increases susceptibility and disease severity.
NSAIDs are first-line treatment.
Chronic cases may require DMARDs or biologic therapy.
Early diagnosis improves long-term outcomes.

References & More

Jogu P, Swamy V, Maher L. Reactive Arthritis. [Updated 2026 May 15]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK499831/
Barth, W F, and K Segal. “Reactive arthritis (Reiter’s syndrome).” American family physician vol. 60,2 (1999): 499-503, 507. Link
Amor, B. “Reiter’s syndrome. Diagnosis and clinical features.” Rheumatic diseases clinics of North America vol. 24,4 (1998): 677-95, vii. doi:10.1016/s0889-857x(05)70037-5. Link
Selmi C, Gershwin ME. Diagnosis and classification of reactive arthritis. Autoimmun Rev. 2014 Apr-May;13(4-5):546-9. PubMed
Hannu T. Reactive arthritis. Best Pract Res Clin Rheumatol. 2011 Jun;25(3):347-57. PubMed