Urine straining is a collection method used to capture small, solid particles that pass from the body, most notably kidney stones. This procedure involves filtering all urine passed over a specific period, usually under the recommendation of a healthcare provider. The primary goal is to retrieve the stone or any resulting fragments for further examination.
Why Urine Straining is Necessary
The collection of a passed kidney stone is necessary because analyzing its chemical makeup is the only way to guide long-term prevention strategies. A laboratory analysis determines the composition of the stone, which can be made of substances like calcium oxalate, uric acid, or struvite. Understanding the specific type of stone is fundamental for the physician to determine the underlying cause of its formation.
Knowing the composition helps tailor a treatment plan to prevent the recurrence of future stones. For example, treatment for a uric acid stone requires different dietary or medication adjustments than for calcium stones, which are the most common type.
Essential Materials and Preparation
The most effective tool for this procedure is a specialized urine strainer, often provided by the healthcare provider, which features a fine mesh filter designed to catch small fragments. If a medical strainer is unavailable, a fine mesh sieve or a coffee filter may be used, but always confirm the acceptable alternative with a physician. Before beginning the collection period, secure a clean, wide-mouthed container to urinate into.
Preparation also involves having a designated, sealed container ready for storing any collected material. This container should be a screw-capped, plastic vial and clearly labeled with your name and the date you began straining. Disposable gloves are helpful for maintaining proper hygiene. The strainer must be rinsed thoroughly after each use to ensure it is clean and ready for the next void.
Step-by-Step Straining Procedure
The process requires straining every time you urinate, as the passage of stones or fragments can be unpredictable and occur over several days or weeks. Begin by urinating directly into the clean, wide-mouthed collection container, ensuring all urine is captured. Position the fine mesh strainer over a second receptacle, such as the toilet bowl.
Pour the collected urine through the strainer, allowing the liquid to pass through the mesh while any solid material is retained. After filtering, visually inspect the strainer for solid particles, which can be small, sand-like grains or larger fragments. This consistent effort should continue until 24 hours after the pain associated with the stone passage has stopped.
If no solid material is found, the strained liquid can be disposed of in the toilet. The strainer must then be thoroughly rinsed with warm water and mild soap to remove any residue. Allow the strainer to air dry completely before its next use to prevent bacterial growth.
If a particle is found, carefully transfer it from the strainer to the designated storage container. This diligent collection ensures the stone is captured for the necessary analysis.
Handling and Storage of Collected Material
Once a stone or fragment is captured, carefully transfer it to the provided screw-capped, plastic container. First, clean any blood or foreign material from the stone with water. The stone must then be air dried thoroughly at room temperature, ideally for a minimum of 24 hours, placed on a clean paper towel or tissue.
The stone must be submitted completely dry, as residual moisture can interfere with the analytical procedure. Do not submit the specimen in any liquid, such as formalin, or tape the stone to the container. The sealed and labeled container should be delivered promptly to the physician or laboratory for chemical analysis.