Immunodiagnosis of pneumococcal meningitis using Dot-enzyme-linked immunosorbent assay.

A diagnosis of bacterial meningitis requires isolation of the pathogen from cerebrospinal fluid (CSF). However, cultures of CSF are usually insensitive, thus, in the majority of patients, the etiology is rarely determined. A total of 90 CSF samples from pediatric patients with clinical diagnosis of bacterial meningitis were evaluated by Dot-ELISA. This method was standardized in order to detect pneumococcal polysaccharide antigen in CSF samples previously treated with 0.1 M EDTA and dotted on nitrocellulose membrane strips. Pneumococcal omniserum diluted 1:200 was employed for pneumococcal antigen detection. Dot-ELISA showed relative indices of 100 and 90 per cent for sensitivity and specificity, respectively. This method is cheaper than counter immunoelectrophoresis for pneumococcal antigen detection.