[Juvenile rheumatoid arthritis: Characterisation of its clinical variations (author's transl)]

This study of 42 patients affected with juvenile rheumatoid arthritis (JRA), in which two defined clinical forms are established: febrile and non-febrile. Patients with JRA with high temperatures for more than 3 weeks, are included in the febrile form when any other cause for the fever can be excluded. In this study, 18 patients had febrile JRA, and the main clinical features were the higher number of joints involved, the presence of rash and the higher incidence of increase in size of the liver and/or spleen. Laboratory studies in cases affected by febrile JRA are characterized by higher frequency of high white blood count (p less than 0.001) and low frequency of rheumatoid factors (0.025 less than p less than 0.05) and antinuclear antibodies (0.001 less than p less than 0.005). Another finding is the incidence of microvasculitis: 31% in a group of 38 patients with JRA. Although microvasculitis is more frequent in the form of JRA without fever. it is a statistically significant characteristic of both forms of JRA described.