Rapid etiological diagnosis of pyogenic meningitis by coagglutination, latex agglutination and immunoosmophoresis of cerebrospinal fluid, serum and urine.

Three rapid diagnostic methods for the detection of bacterial antigen-COA (Coagglutination), LA (latex agglutination) and IEOP (immunoelectroosmophoresis); DM (direct microscopy after Gram staining) and culture of cerebrospinal fluid (CSF) have been compared in 53 bacterial meningitis patients and in 13 controls. Urine samples were assayed for antigens in connection with CSF in 32 for COA, LA, and IEOP. The cause of meningitis was S. pneumoniae in 31, H. influenzae type b in 16 and N. meningitidis in 6 using the methods for diagnosis by LA in 100%, COA in 94%, culture in 89%, IEOP in 81% and DM in 78% of the CSF samples. None of the CSF from controls were positive by any of the methods. LA and COA detected antigen in CSF in all 4 patients on 4th and 5th day of treatment but none of the tests were helpful 7-10 days later. LA was effective in detecting antigen in urine in 10/10 (100%) H. influenzae type b, 17/20 (85%) S. pneumoniae prior to antibiotic treatment. IEOP was helpful in antigen detection better in serum than in urine in 5/6 H. influenzae type b and 9/11 S. pneumoniae meningitis. In general we have found LA and COA as simple, rapid specific and sensitive tests and can be applied even in field situations and that LA can be used for antigen detection in urine and IEOP in serum. A large scale study is needed in order to standardize methods for antigen detection in serum and urine.