ATLASINTESTINAL PARASITES (Protozoa)
      SPOROZOEA Order: Eucoccidiida

      CYCLOSPORA CAYETANENSIS

      cyc-1-ic

      Cyclospora cayetanensis oocyst: C.cayetanensis is a recently described
      protozoon associated with prolonged self-limiting and relapsing diarrhea.
      It has a world wide distribution with a higher prevalence
      in tropical and subtropical countries.
      (Wet mount preparation).


      cyc1a-ic

      Cyclospora cayetanensis oocyst: oocysts appear as spherical
      refractive organisms of 8-10 µm in diameter, containing
      a variable number (5-10) of globular inclusions.
      (Wet mount preparation).


      By Dr. Marc Lontie.

      cyclosLon-ic

      Cyclospora cayetanensis: Wet mount preparation.


      cyc2-ic

      Cyclospora cayetanensis oocyst: the oocysts have a characteristic autofluorescence
      under UV light (with a 340-380 BP filter), even after preservation in formalin.
      The oocysts appear neon blue.


      cyc3-ic

      Cyclospora cayetanensis oocyst: oocysts stain variably with the modified
      acid-fast stain used for Cryptosporidium.
      Typical oocyst stained in red.
      (Acid-fast stain).


      cyc4-ic

      Cyclospora cayetanensis oocyst: differentiation with Cryptosporidium oocysts
      is based on the characteristic shape of the stained oocyst
      and the size (8-10 µm in diameter).
      (Compare with yeasts on the left).


      cyc5-ic

      Cyclospora cayetanensis oocyst: oocysts stain variably from red to pink.
      The infection is usually self-limiting but is relapsing.
      Co-trimoxazole seems to be the treatment of choice.


      cyc6-ic

      Cyclospora cayetanensis oocyst: oocysts stain variably;
      some oocysts do not stain at all and appear as ghost oocysts.


      cyc7-ic

      Sporulated C.cayetanensis: oocysts are excreted as unsporulated.
      Sporulation occurs in 15 days at room temperature in K dichromate 2,5%.
      Assesment of sporulation can be confirmed with light microscopy by observing
      two sporocysts within each oocyst.