Introduction to Reactive Arthritis In Pediatric Practice

Reactive arthritis although not much commonly seen in pediatric practice is defined as a group of inflammatory arthritis which follow bacterial or viral infection particularly involving respiratory, gastrointestinal and genitourinary tracts.

Mode of Onset
Infection typically precedes development of arthritis by 1 to 4 weeks, with approximately 80% of cases being preceded by gastroenteritis.

Some Precipitating Organisms
Mycoplasma, Chlamydia, yersinia, Salmonella, Shigella, Campylobacter, Epstein barr virus, Parvovirus B19,and enteroviruses.

Clinical presentation
Patient presents with symptoms like fever, weight loss and fatigue as well as dermatological and opthalmological findings. For example Reiter syndrome is a reactive arthritis in the presence of conjunctivitis and urethritis.

Association with HLA B 27
approximately 50 -65 % of cases have a strong association with HLA B 27.

Laboratory StudiesMay demonstrate evidence of systemic inflammation including leukocytosis, thrombocytosis and elevated ESR and CRP. Autoantibodies are typically absent. Stool cultures and serum titres for chlamydia and mycoplasma may help in identifying the organism involved. Joint fluid analysis may be helpful to distinguish a septic arthritis from reactive arthritis.

Prognosis
Arthritis can last weeks to months with eventual remission versus development of recurrent episodes