[Ankylosing spondylitis with childhood onset. Description of a clinical case].

The terms "spondyloarthropathy" and "spondyloarthritis" have been recently introduced to indicate a group of syndromes associated in clinical and genetical peculiarities. The "ankylosing spondylitis with childhood onset", that is usually considered very rare, is, as a matter of fact, a disease difficult to diagnose because of the partial overlap with the "pauciarticular juvenile rheumatoid arthritis type II" for clinical and laboratory data. The Authors, after a recapitulation of the "pauciarticular juvenile rheumatoid arthritis type II" and of the "ankylosing spondylitis with childhood onset" diagnosis definition elements, propose a description of a clinical case that came to their observation. The clinical picture described, even though it presented some clinical peculiarities (particularly a primitive affection of the lumbosacral spine), some radiographic peculiarities (the precocious demineralization of the affected segments) and laboratory characteristics (positive F.A.N. to diffuse pattern) seemed a form of "ankylosing spondylitis with childhood onset", apparently primitive.