Observations on the morphology of mycobacterium leprae by ordinary optics, phase microscopy, and electron microscopy

ABSTRACT

Mycobacterium leprae has been studied with the aid of the ordinary and phase microscopes, and the electron microscope. It has been found that treatment of M. leprae with distilled water or chloroform prior to examination produces artefacts. Fixation of material is the vapor of 2 per cent osmic acid solution gives the best results for the electron microscope study of the bacillus. The following forms representing the morphological variants of this mycobacterium have been established with certainty from this study (a) a short, oval type of cells with one or two polar condensations; (b) elongate types with double polar condensations; (c) very long types with alternate light and dark zones; and (d) homogeneously dark, elongate types. The possible significance and relationships of these variants have been discussed.