The sitz marker test is a diagnostic procedure that evaluates how the large intestine moves waste. It helps identify issues related to bowel motility, providing insights into the transit time of contents through the colon. This test is often recommended for individuals experiencing chronic constipation or other bowel movement irregularities when standard diagnostic tests are inconclusive.
How the Sitz Marker Test Works
The sitz marker test is a non-invasive imaging procedure that assesses the movement of materials through the colon. It begins with a patient swallowing a capsule containing small, radiopaque markers designed to be visible on X-ray images.
After ingesting the capsule, individuals continue their normal daily activities and diet, avoiding laxatives, enemas, or suppositories. The capsule dissolves, releasing the 24 markers, which then travel through the digestive tract. An abdominal X-ray is performed five days after the capsule is swallowed to track the markers’ progression and location within the colon.
Conditions Identified by the Test
The sitz marker test diagnoses specific types of constipation and motility disorders. It helps differentiate between various causes of chronic constipation. One primary condition identified is slow transit constipation. This occurs when the colon’s muscular contractions are insufficient to move waste through the intestines at a normal pace.
The test can also diagnose colonic inertia, a more severe form of slow transit constipation where the colon’s natural movements are significantly diminished. Additionally, the sitz marker test helps pinpoint functional outlet obstruction or defecation disorders. These conditions involve difficulties with the final expulsion of stool from the rectum, even if transit through the rest of the colon is normal.
Understanding Your Test Results
Interpreting sitz marker test results involves analyzing the number and distribution of retained markers on the abdominal X-ray. A normal colonic transit time is indicated if five or fewer markers remain in the colon after five days.
An abnormal result, suggesting a motility disorder, occurs if six or more markers are still present on day five. If these markers are scattered throughout different segments of the colon, it points to generalized colonic hypomotility or inertia, consistent with slow transit constipation. Conversely, if markers are primarily accumulated in the rectosigmoid colon or rectum, it suggests a functional outlet delay or obstruction. The pattern of marker retention guides healthcare providers in determining the specific type of motility issue affecting the colon.