Juvenile chronic polyarthritis: clinical sub-groups and response to medication.

Juvenile ankylosing spondylitis, as a clinical entity, is outlined. A double-blind trial compared Safapryn and Butazolidin, each given for 3 months, for 15 treatment periods in 11 patients. No differences were shown, but the study highlighted the problems of assessing this condition, and some comments are made, hopefully, to guide further investigators in this field.