title: Complement studies in splenectomized patients.
abstract: Total haemolytic complement activity, C2, C5, total alternative pathway activity, factor B, and C3d were measured in 85 splenectomized patients from 1 month to 32 years after splenectomy. Furthermore the patients were investigated for circulating immune complexes. No major deficiencies of the complement factors were detected. In a few patients a reduced C2 level was caused by genetically determined defects or was due to complement consumption in conjunction with circulating immune complexes. The complement levels were normal in 2 patients who had survived overwhelming infections after splenectomy. C5 was elevated in a major proportion of the patients, and it is suggested that this might be caused by post-splenectomy monocytosis. Circulating immune complexes were found in 20% of all cases, irrespective of the presence of residual splenic tissue. Thus the commonly cited impairment of the complement system after splenectomy does not seem to be substantiated, and the deficient resistance against bacterial infections in splenectomized patients does not seem to include abnormalities of the complement system.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D000936:Antigen-Antibody Complex / Q000032:analysis; D002648:Child; D002828:Choristoma / Q000276:immunology; D003175:Complement C2 / Q000172:deficiency / Q000235:genetics; D003165:Complement System Proteins / Q000032:analysis*; D005260:Female; D006168:Guinea Pigs; D006801:Humans; D008583:Meningitis, Haemophilus / Q000209:etiology; D008586:Meningitis, Pneumococcal / Q000209:etiology; D008875:Middle Aged; D013154:Spleen; D013156:Splenectomy / Q000009:adverse effects
chemical_list: D000936:Antigen-Antibody Complex; D003175:Complement C2; D003165:Complement System Proteins