Trematode eggs are typically found in which part of a fecal sample?

Trematode eggs are typically found in which part of a fecal sample?

• A. Flotation layer
• B. In the sediment
• C. In the urine
• D. In the sediment of a prepared sample

Answer: (D)

Trematode eggs are relatively dense and don’t reliably float in standard flotation solutions. In fecal exams, we use a sedimentation or concentrating method, which pulls the heavy eggs down into the sediment. When you prepare and examine a sedimented sample, that concentrated sediment on the slide is where trematode eggs are most likely to be found. Urine is not relevant for a fecal exam, and stating the sediment of a prepared sample specifically reflects the common practice of examining the concentrated sediment after processing.

Trematode eggs are relatively dense and don’t reliably float in standard flotation solutions. In fecal exams, we use a sedimentation or concentrating method, which pulls the heavy eggs down into the sediment. When you prepare and examine a sedimented sample, that concentrated sediment on the slide is where trematode eggs are most likely to be found. Urine is not relevant for a fecal exam, and stating the sediment of a prepared sample specifically reflects the common practice of examining the concentrated sediment after processing.