Ova and Parasite (O&P) Examinations

Introduction | Macroscopic | Microscopic |

Microscopic Examination - Ova and Parasite Examination

Introduction | Direct Wet Smear | Concentration | Permanent Stained Smear

Permanent Stained Smear

Introduction | Trichrome Stain | Iron Hematoxylin Stain | Modified Iron Hematoxylin Stain | Procedure Review

Iron Hematoxylin Stain

Procedures

Mercury-Based Fixatives

Note: In all staining procedures for fecal and gastrointestinal tract specimens, the term xylene will be used in the generic sense. Xylene substitutes are recommended for the safety of all personnel performing these procedures.

Prepare slide for staining as previously described (for SAF smears, proceed to step 4).
Place slide in 70% ethanol for 5 min.
Place slide in the iodine-70% ethanol (70% alcohol to which is added enough D'Antoni's iodine to obtain a strong tea color) solution for 2 to 5 min.
Place in 70% ethanol for 5 min. Begin procedure for SAF?fixed slides at this point.*
Wash slide in running tap water (constant stream of water into the container) for 10 min.
Place slide in iron hematoxylin working solution for 4 to 5 min.
Wash slide in running tap water (constant stream of water into the container) for 10 min.
Place slide in 70% ethanol for 5 min.*
Place slide in 95% ethanol for 5 min.*
Place slide in two changes of 100% ethanol for 5 min each.*
Place slide in two changes of xylene for 5 min each.*
Add Permount to the stained area of the slide and cover with a coverslip. Note An alternative method to using mounting medium can be seen on page 520.
Examine the smear microscopically with the 100 x objective. Examine at least 200 to 300 oil immersion fields before reporting a negative result.

*Slides may be held up to 24 h in these solutions without harming the quality of the smear or stainability of organisms.

Non-Mercury-Based Fixatives

Prepare slide for staining as previously described.
Place in 70% ethanol for 5 min.*
Wash slide in running tap water (constant stream of water into the container) for 10 min.
Place slide in iron hematoxylin working solution for 4 to 5 min.
Wash slide in running tap water (constant stream of water into the container) for 10 min.
Place slide in 70% ethanol for 5 min.*
Place slide in 95% ethanol for 5 min.*
Place slide in two changes of 100% ethanol for 5 min each.*
Place slide in two changes of xylene for 5 min each.*
Add Permount to the stained area of the slide and cover with a coverslip. Note An alternative method to using mounting medium can be seen in the Trichrome Staining procedure.
Examine the smear microscopically with the 100 x objective. Examine at least 200 to 300 oil immersion fields before reporting a negative result.

*Slides may be held up to 24 h in these solutions without harming the quality of the smear or stainability of organisms.