ABSTRACT
A 17-year-old boy had suffered from right ankle arthralgia when he was 13 years old. He also had bilaterally congested conjunctivas and were erythematous around his right ankle joint. A soft tissue echo showed swelling of the right ankle joint. A Ga 67 scan revealed a focal elevated uptake in the right ankle, but a bone scan was negative. Reactive arthritis was suspected due to conjunctivitis, arthritis and a previous episode of watery diarrhea. An ophthalmologic examination showed no evidence of uveitis. Laboratory data were negative for rheumatoid factor, antinuclear antibody and anti-ds DNA. Erythrocyte sedimentation rate (ESR) was 40 mm/hr and a histocompatibility test was positive for antigen B27. Based on the diagnosis of cellulitis and reactive arthritis, oxacillin and naproxen were given for 14 days. During follow-up at the OPD, bilateral arthralgia of the ankle joints was noted and a sonography showed bilateral edematous ankle joints. Juvenile ankylosing spondylitis (JAS) was suspected. Two years later, he had lower back pain and arthralgia of the knee joints with uveitis of the right eye. He was treated with naproxen and prednisolone. Because few JAS cases initially present as axial arthropathy or enthesopathy and uveitis is uncommon in children, we presented the case with a review of literature and conclusion that the possibility of JAS should be considered in young adolescent boys with arthritis of the lower limbs, enthesitis, a family history of related diseases and positive HLA-B27, as well as negative rheumatoid factor (RF) and anti-nuclear antibody (ANA) results.