Final answer:
To prepare a direct fecal smear with watery stool, place a drop of the specimen on a microscope slide, then cover with a coverslip. Staining with iodine or similar agents is commonly done to enhance visualization of any present bacteria. Consistency in smear preparation is important for accurate diagnostic comparison across multiple days.
Step-by-step explanation:
When preparing a direct fecal smear with watery stool, you will need to carefully place a drop of the specimen onto the microscope slide. If the stool is already watery, it is suitable for direct microscopic examination without additional liquid. Solid specimens would typically require the addition of water or another appropriate liquid to create a wet mount, but this step is unnecessary with a watery sample. A coverslip is then placed on top of the slide. Often, stains like iodine are added to enhance contrast and help in the visualization of the stool contents, including bacteria that may appear pink or purple with a Gram stain.
In some cases, additional diagnostic tests such as immunoassays or molecular techniques might be used to identify specific pathogens like Shigella species. If the examination is part of a series over several days, it is important to prepare consistent smears for comparison. The presence of white blood cells and blood is a common finding in fecal samples and can help in making a diagnosis.
To enhance the visibility of specific features within the stool specimen, staining reagents like iodine may be carefully dropped onto the smear and rinsed after a short period. This step allows for better differentiation of cellular structures when viewed under the microscope at high magnifications, such as 1000X.