[The ultrastructural characteristics of Neisseria meningitidis strains isolated in different forms of infection].

The electron microscopic study of cell populations of the first generation of several N.meningitidis strains, isolated from humans and grown on artificial culture medium (Hottinger's serum agar) has made it possible to establish that these organisms are morphologically heterogeneous. It was manifested by the presence of 7 morphological variants of cells in their cultures (different strains have different proportions of these variants): (a) "normal" and similar to normal diplococcal variants; (b) atypically dividing cells; (c) spheroplastic forms; (d) protoplastic forms (typical and atypical); (e) variably gemmating forms; (f) microforms and (g) gigantic forms. These data are of interest for the microbiological diagnosis of meningitis.