Canadian Society for Medical Laboratory Science (CSMLS) Practice Exam

When is the best time to collect specimens for pinworm ova?

1. During the day

2. During the afternoon

3. Immediately following a bowel movement

4. Before the patient gets out of bed

The correct answer is: Before the patient gets out of bed

The optimal time to collect specimens for pinworm ova is before the patient gets out of bed, primarily because this is when the female pinworms are most active and likely to lay their eggs. During the night, pinworms typically emerge from the rectum to deposit their eggs in the perianal area. Collecting specimens at this time enhances the chances of obtaining viable samples, which may not be present at other times of the day when movement, bathing, or clothing could remove or obscure the eggs. This strategy is particularly vital in ensuring an accurate diagnosis of pinworm infestation. During the day or afternoon, pinworms may not be as active, and bowel movements can interfere with the collection process, leading to a lower likelihood of finding eggs in the sample. Thus, timing the collection when eggs are likely to be present is crucial for effective diagnosis.