Comparison of the Coombs Test With Other Methods for Brucella Agglutinins in Human Serum 1

Abstract

During the past year we have compared several techniques for testing human sera for Brucella agglutinins. These have included a tube dilution method, the rapid slide method (Huddleson) and a rapid slide or screening test designed by Castaneda (1). In addition, a blocking test and a modification of the indirect Coombs test were investigated. High speed centrifugation of Brucellaserum mixtures was also used to increase the titer of Brucella agglutinins.Several unsuccessful attempts also were made to adapt the Middlebrook-Dubos (2) hemagglutination method to the detection of antibodies against Brucella. In addition, paper chromatograms were made in attempts to differentiate specific from non-specific Brucella agglutinins by the method of Hess and Roepke (3).Sera from 104 adults were studied. Of these subjects, 27 had brucellosis proved by culture, 28 had presumptive evidence of brucellosis, and 49 had no evidence of infection with Brucella and were classed as "normal" controls. METHODSVenous blood was obtained aseptically and allowed to clot in a sterile glass tube in a refrigerator. The serum was separated within a few hours. It was not heatinactivated but was tested immediately or stored in a deep-freeze cabinet at O°C. until tested.Tube dilution agglutination method. The agglutinin titer was determined by a modification of the method of Fitch, Donham, Bishop, and Boyd (4). The serum was diluted two-fold serially from 1: 10 to 1: 2,560 with 0.85 per cent saline solution. Brucella abortus antigen (0.5 ml.) was added to 0.5 ml. of saline (control) and 0.5 ml. of each dilution of the serum in separate tubes.' The

Brucellosis and International Travel

“…25 In other rare situations,blocking antibodies may be found, which also leads to a negative serologic test.If these blocking antibodies are suspected in a patient where a high suspicion of brucellosis is present, one should perform a Coombs test or a specific test for blocking antibodies. [25][26][27] The Rose Bengal test is a rapid screening test; however, confirmation of a positive test is always needed. Finally, ELISA is suggested to be a more sensitive and rapid way of diagnosing brucellosis, but is much more expensive, especially for hospitals in endemic countries, where the test would be done frequently.…”

Immunoglobulin m deficiency in the immune response of patients with rheumatoid arthritis

“…The test tube agglutination method of Hall and Manion (14) was used for measuring antibody to Brucella. Each serum was titered in two rows, one row containing 0.1M penicillamine to destroy the activity of IgM antibodies.…”

Brucellosis in Children

“…On the other hand, what he has may be counted on and the adult might more often have achlorhydria. Hall (1950) observed that the blood serum of infants of 3 months or less was strongly bactericidal for Br. abortus, that two-thirds of infants between 4 and 16 months had serum with little or no bactericidal activity, but that in children over 18 months, as well as in normal adults, strong bactericidal action against Br. abortus was shown by the serum. He concluded that the protection of young infants was due to passive antibodies from the mother, BRUCELLOSIS IN CHILDREN powers of serum in later life.…”