Blastocystis hominis: origin and significance of vacuolar and granular forms

Parasitol Res. 2000 Jan;86(1):8-10. doi: 10.1007/pl00008506.


Using supravital neutral red staining and light microscopy, individual Blastocystis organisms, subcultured from clinical isolates in modified monophasic Robinson's medium, were followed over various periods on glass slides. A rapid transition from uniformly stained to granular and vacuolated forms preceded the organism's death as evidenced by pale staining and Brownian motion in the cell's interior. Granular and vacuolar forms of Blastocystis may indicate degenerative changes in individual cells, fixation artifact, or both.

MeSH terms

  • Animals
  • Artifacts
  • Blastocystis Infections / parasitology
  • Blastocystis hominis / growth & development*
  • Blastocystis hominis / ultrastructure*
  • Culture Media
  • Humans
  • Microscopy, Fluorescence
  • Neutral Red
  • Staining and Labeling
  • Vacuoles / ultrastructure


  • Culture Media
  • Neutral Red