RESUMO
Experiments have been performed on 25 synovial fluid samples from patients with juvenile chronic arthritis (mono- and polyarticular forms) and with hydroarthrosis, the latter considered as controls. By cytomorphologic studies, we determined the cellularity, ragocytosis and synoviocytogram of the synovial fluid cellular pellet and found out that the synovial fluid from cases of juvenile chronic arthritis is characterised by cytosis (11.270/mm3; 15.275/mm3), polynucleosis (67.3%, 72.2%) and ragocytosis (12.8%, 17.5%) whereas hydroarthrosis synovial fluid is characterised by lymphocytosis (47.8%). Ultrastructurally, ragocyte-like polymorphonuclear cells are characterised by: a) segmentation of the nucleus and preferential concentration of chromatime on the periphery of the nuclear membrane: b) frequent intracytoplasmic inclusions and phagolysosomes. Phagocyte-like mononuclear cells present numerous inclusions and phagolysosomes, certainly indicating an endocytic activity. Lymphocytes are characterised by a narrow cytoplasmic rim, presenting relatively few cellular organelles. They coexist with immunely activated lymphocytes rich in cytoplasm, mitochondria and endoplasmic reticle. Corroboration of cytomorphological and ultrastructural date enables us to explain the morphological modifications and emphasize their importance in juvenile chronic arthritis pathogenesis and diagnosis.