Reiter’s Syndrome

Reiter’s Syndrome/Disease) is an asymmetric polyarthritis which affect large joints of the lower extremities, small joints of the feet and axial skeleton (spondylitis). Reactive arthritis (ReA) is characterised by a triad of arthritis, urethritis, and conjunctivitis. It may be accompanied by mucocutaneous lesions. This disease is more common in males with an age of onset of about 15 to 35 years.

Reactive Arthritis is precipitated by mucosal bacterial infection, generally in genitourinary or gastrointestinal tract (GIT). It is sterile or aseptic, probably immune-mediated inflammatory process originating distant to the primary focus of infection.

Reactive Arthritis belongs to seronegative (negative serological tests for rheumatoid factor) spondyloarthropathies (SSAs). Spondyloarthropathies describe a group of interrelated inflammatory arthropathies which affect the synovium and extra-articular sites. There is strong association with HLA-B27 antigen.

References

Kanski Jack J, Thomas Dafydd J. The Eye in Systemic Disease Second Edition. Butterworth-Heinemann Ltd, 1990. P 43-44.

Marchiori Dennis M. Clinical Imaging- With Skeletal, Chest, and Abdomen Pattern Differentials Second Edition. Elsevier Mosby 2004. P 510-514.

Koopman William J, Boulware Dennis W, Heudebert Gustavo R. Clinical Primer of Rheumatology Lippincott Williams & Wilkins 2003. P 135-145.

Bellamy Nicholas. Colour Atlas of Clinical Rheumatology. MTP Press Limited- a member of the Kluwer Academic Publishers Group 1985. P 90.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5151165/

https://pubmed.ncbi.nlm.nih.gov/3486396/

https://www.sciencedirect.com/topics/immunology-and-microbiology/reiters-syndrome

https://emedicine.medscape.com/article/331347-overview

https://www.researchgate.net/publication/51475879_Keratitis_in_Reactive_Arthritis_Reiter_Syndrome_in_Childhood

https://pmj.bmj.com/content/76/902/791

General systemic symptoms

Arthritis

• Fever
• Urethritis
• Arthritis

Periarticular

• Plantar fasciitis
• Achilles tendonitis
• Pain in heels (Calcaneal spur)

Extra-articular

• Painless transient ulcers in mouth
• Painless erythematosus erosion of glans penis (circinata balanitis.
• Onycholysis (separation of nail from skin underneath)
• Genitourinary lesions such as prostatitis and cystitis

The Cause of ReA appears to be

• Linked to genetic factors.
• Linked to infection.

Pathogenesis

Pathogenesis of SSAs is poorly understood. Three characteristic features to be considered are

• Strong association with HLA-B27
• Association with number of bowel pathogens
• Presence of enthesitis as an initial pathological lesion

Diagnosis depends upon clinical examination and investigations.

Diagnostic triad of ReA consists of

• Urethritis
• Arthritis
• Conjunctivitis

The components of triad may not exist concurrently. Incomplete forms of disorder (particularly urethritis and arthritis without conjunctivitis) are common.

American College of Rheumatology (ACR) has defined ReA as an episode of peripheral arthritis of more than one month duration occurring in association with urethritis or cervicitis, or both.

ReA typically occurs within days or weeks of urinary tract infection or dysentery.

Patient presents with lower extremity polyarthritis in addition to one or more of the following general features.

General features

• Urethritis.
• Dysentery.
• Arthritis.
• Changes in nails.
• Pain in heels
• Low back pain
• Balanitis circinata is characteristic finding of ReA. It is characterised by small painless ulcers on glans penis and urethral meatus.
• Keratoderma blenorrhagica is also characteristic finding of ReA. It is characterised by hyperkeratotic skin lesions usually on the plantar surface of feet and palms of the hands. It may occur anywhere on the body including toes, trunk, and penis.

Radiological findings

Like other SSAs, ReA is associated with spondylitis and sacroilitis. Radiographically, changes associated with ReA are similar to changes produced by PsA. However, propensity to affect lower extremities is higher in ReA as compared to PsA, which affects upper extremities.

• Feet: Metatarsophalangeal (MTP), interphalangeal (IP) articulations in feet, specifically of the first digit, and calcaneus bone are primarily affected. 
• Large joints of lower extremities: The knee and ankle are frequently affected as compared to hip joint. Radiographic findings show joint effusion and loss of joint space, soft tissue swelling, and erosions. 
• Tendons: There is tenosynovitis particularly in Achilles tendon of feet. 
• Sacroiliac joints: Sacroilitis may be bilateral symmetric/asymmetric or unilateral. 

Laboratory findings

Laboratory findings are similar to other SSAs such as

• Leucocytosis
• Thrombocytosis
• Positive HLA-B27 in about three-fourth of patients
• Negative rheumatoid factor (RF)

Differential diagnosis

• Psoriatic arthritis (PsA).
• Ankylosing spondylitis
• Enteropathic/Inflammatory bowel disease (IBD) arthropathies.
• Septic arthritis.

Management involves joint protection, maintenance of function, suppression of inflammation, patient education, pain relief, and eradication of infection where indicated.

• Education
• Physical and occupational therapy.
• Non-steroidal anti-inflammatory drugs (NSAIDs)
• Intra-articular injections of steroids.
• Perilesional steroid injections.
• Antibiotics.

Second line therapy

• Disease-modifying anti-rheumatic drugs (DMARDs
• Immunosuppressive drugs

Prognosis

ReA has variable natural history and course of disease, but typically follows a self limited course.