Diagnosis of bacterial meningitis and septicemia by serum counterimmunoelectrophoresis

We compare the results obtained by counterimmunoelectrophoresis in samples of serum and cerebrospinal fluid with microbiologic methods for 3,298 patients suspected of bacterial meningitis and/or septicemia at Instituto Adolfo Lutz, Säo Paulo, in a retrospective study of the period from July 1988 to July 1994. Of the 415 patients (12.6 percent of the total cases studied) who were positive by the serum test, only 249 (7.6 percent of the total cases studied) were also positive when cerebrospinal fluid was assayed. Thus, 40 percent of the positives (5.6 percent of the total) were identifiable by analysis of serum but not of cerebrospinal fluid. Neisseria meningitidis accounted for 77.7 percent (129) and Haemophilus influenzae for 22.3 percent (37) of the positive results obtained only when serum was examined. These...

Production and immunochemical characterization of Neisseria meningitidis group B antiserum for the diagnosis of purulent meningitis

Unlike Neisseria meningitidis groups A, C, Y and W135, the group B capsular polysaccharide has been shown to be chemically and immunologically identical to the capsular polysaccharide of Escherichia coli K1. Both components are sialic acid homopolymers and are poorly immunogenic. Nevertheless, due to the high incidence of Neisseria meningitidis group B meningitis in the population of the State of São Paulo, preparing antiserum to this serogroup for diagnostic purposes has become a matter of high priority. Of the many immunization schemes proposed, intravenous inoculation of whole bacteria previously inactivated with formaldehyde and simultaneous intradermal inoculation with a mixture of the bacterial polysaccharide fraction and whole bacteria in complete Freund;s adjuvant have produced the best results. The antiserum was treated with immunoadsorbents prepared with aluminum chloride and protein and/or polysaccharide antigens from each of the following heterologous bacteria: Haemophilus influenzae type b, Streptococcus pneumoniae, Escherichia coli other than K1, and Staphylococcus aureus, in order to eliminate cross-reactivity. For quality control analysis, the antiserum was assessed by the immunodiffusion, counterimmunoelectrophoresis, dot-ELISA, and immuno-blot techniques against homologous antigens. Specificity was obtained after treating the antiserum with Haemophilus influenzae type b polysaccharide immunosorbent.