Blood in Stool - Diagnosis

Blood in stools is an indicative of internal bleeding. Normal bowel movement produces medium brown color stools. However, blood in stool is a cause of worry, and it means something is wrong with the large intestine. In fact, blood in the stool is the symptom of a number of diseases, involving the stomach, intestines or the liver.

Hematochezia is the medical term used to describe blood in stools. To put simply, along with stool, the patients also defecate blood. In most cases, bleeding occurs from the rectum, hence hematochezia is also sometimes referred to as rectal bleeding. Also, in majority of hematochezia cases, only a small amount of blood is defecated.

Usually, the toilet paper may show few marks of blood but in moderate to severe cases, one or two spoons of blood is passed down the anus.

Stool Color: The color of the stool drastically changes, if there is red blood in stool. The stool appears bright red and the consulting the doctor is important to diagnose the condition. However, when there is blood in feces, it doesn't means that stool color will always appear red.

Bleeding in the intestines can also cause bowel evacuation that gives rise to black, tarry stools. This unusual stool color that lasts for more than 2 days is certainly not normal and consulting a physician is essential as it may be a symptom of disorder, involving the large intestine or gallbladder.

The color of blood in the stool is a crucial factor in determining the site of bleeding in the large intestine. To be specific, color of the blood will vary depending upon where the bleeding is occurring in the intestine. It is said that farther the location of bleeding from the anus, the darker will be the color of the blood in the stool.

For instance, if the bleeding site is deep inside the colon, the blood appears dark red. On the other hand, if bleeding is taking place near the anus such as the rectum, then the blood color changes to bright red.

In case the site of bleeding is anywhere in the small intestine or the stomach, black bowel movement is the likely outcome. When the blood from the small intestine reaches the large intestine, there it combines with the good bacteria. By the time, the blood from the large intestines reaches the anus, the bacteria stimulate breakdown of blood into its basic components that are black in color. Hence, stools that combine with this blood (that is broken down into its black constituents) appear tarry black.

Fecal Occult Blood Test: This is one test that is used when blood in feces is not visible to the naked eye. In such a case, unusual color may not be seen, due to presence of small amount of blood in stool. This test is the most reliable way to confirm blood in feces.

In order to diagnose the underlying cause, various blood tests are performed. This is a low-cost, non invasive procedure that gives details about the exact quantity of blood in stool sample. An easy way to perform fecal occult blood test is given here:

Guaiac Test: This test involves putting stool sample over a piece of paper that has a thin coating of guaiac. 1-2 drops of hydrogen peroxide are then added to the sample. If discoloration in the stool appears, then one can say that blood is present.

As aforementioned, blood in stools is a warning sign of a disease, more specifically a gastrointestinal disorder. The most common causes of red or tarry stools include stomach ulcers and damage to the veins in the stomach during vomiting. Other causes are given below:

Gastroenteritis: This is a viral infection that attacks the stomach and the intestines. More specifically, it is the inflammation of the gastrointestinal tract that causes bloody diarrhea, if treatment is neglected.

Hemorrhoids: When the veins, located in the anus and rectum area get swollen, the resultant condition is referred as hemorrhoids. When hemorrhoids are present inside the anus, the person may excrete stools that are partially covered with blood.

Constipation: Painful bowel evacuation in which a large stools is removed by damaging the tissue around the anus can cause blood in stool. This is because, the delicate tissue may bleed profusely when it rubs against the passing large stool.

Inflammatory Bowel Syndrome: This is a digestive problem that causes inflammation of the intestinal wall that may results into diarrhea with blood clots in stool.

Inflammatory Bowel Disease: People suffering from inflammatory bowel conditions like ulcerative colitis and Crohn's disease may also show presence of blood in feces. In Crohn's disease, the inflammation is just not restricted superficially but also infiltrates the inner layers of the affected bowel tissue.

While having meals, the ingested food may scrap the inflamed areas of the bowel and cause slight bleeding. Abdominal pain, diarrhea and cramping are some of the most common symptoms of Crohn's disease. On the other hand, ulcerative colitis is typically marked by formation of ulcers or open wounds in the large intestine.

Diverticulitis: This condition that strikes the large intestine causes inflammation and bleeding of the diverticula. Diverticula are protruding sacs that form on the superficial layer of the colon. Thus in diverticulum, the outer side of the colon shows development of bulging pouches. In United States, people over 40 are often diagnosed with diverticulum.

Diverticula are harmless and rarely a cause for concern. However, when these pouches become inflamed and bleed due to an infection, one is bound to experience abdominal pain and an undesirable change in bowel movement.

Colon Cancer: Persistent blood in stools may signal the presence of cancerous growth in the colon. The unnatural division of cells usually begins in the inner lining of the colon and eventually spreads to the adjoining areas. People with colon polyps (small benign projections) are at increased risk of colon cancer. This is because, these polyps can turn cancerous and so they should be removed at the earliest.