[Group specific antibodies in generalized forms of meningococcal infection].

Seroconversion was revealed in the indirect hemagglutination test with a stable erythrocytic diagnostic agent containing meningococcus antigen of serogroup A in 93.4% of patients with generalized forms of meningococcus infection. A study of the sera obtained at various periods of the disease from 168 patients showed that the antibodies increased sharply during the first days, reaching the maximum (1:2560--1:10240) on the 5th--10th day of the disease; then the titres decreased somewhat becoming stabilizaed at the same level up to recovery. In 75--92% of the persons of control group (patients with meningites of nonmeningococcal etiology, healthy persons and those suffering from gonorrhea) the antibody titre was not over 1:20--1:40; no dynamic increase in its level was noted. The diagnostic value of the reaction for differentiation of meningococcus etiology from other meningites is emphasized.