[Quantification of serum interference in immune complex phagocytosis in seronegative spondylarthropaties, systemic lupus erythematosus, and rheumatoid disease].
Pathological samples (55) of serum selected from patients with Seronegative Spondylarthropathies, Systemic Lupus Erythematosus and Rheumatoid Disease were studied. The serum of all these patients showed negative rheumatoid factor by latex fixation reaction. The determination of the interference on the phagocytosis of gamma globulin aggregated by guinea pig's macrophages was obtained by one formula. The serum characterization was determined by selecting the ones that presented the most expressive results in the phagocytosis interference, by facilitation or inhibition. The results, in absolute and percentage values, showed the predominance of the interference phenomenon in phagocytosis, with significant statistical values (p < 0.05), when compared with normal serum. The comparative analysis among the diseases studied in the quantification of the serum interference in the phagocytosis of the immunocomplexes has not showed any significant difference. The phagocytosis inhibition occurred with more preponderance in the serum of patients with Reiter's Syndrome and Psoriatic Arthritis; in serum patients with Reiter's Syndrome there was a statistically significant difference in the inhibition of the phagocytosis (p = 0.0247). The serum characterization did not show that the serum fraction was responsible for the phagocytosis interference. In this stage it has been verified that there has not been an uniformity in the graphic curve of dilutions studied. The possibility of the existence of more than one element with interference in the phagocytosis of the studied immunocomplexes was mentioned.