The appearance of blood, particularly in the form of clots, when passing a bowel movement can be alarming and requires medical attention. A blood clot in stool, known medically as hematochezia when bright red, is a clump of congealed blood that has formed within the gastrointestinal (GI) tract before being evacuated. This clotting process occurs when bleeding is significant enough to allow the blood’s components, like platelets and fibrin, to aggregate before mixing completely with the stool. Finding blood clots in your stool is a sign of internal bleeding and necessitates a prompt evaluation by a healthcare professional to identify the source and determine the appropriate treatment plan.
Visual Identification of Clots and Bloody Stool
Blood clots in stool typically present as gelatinous, dark, or firm masses that are distinct from the surrounding fecal material. The color of the clot provides an important clue about the location of the bleeding within the digestive system. Clots that are bright red or maroon usually indicate a source in the lower GI tract, including the colon, rectum, or anus, because the blood has not been exposed to digestive enzymes for a long period of time.
A clot can vary in size, sometimes appearing as small, dark, jelly-like globs, or in more significant cases, resembling a larger, liver-like mass. The presence of mucus mixed with the blood clot can suggest inflammation or irritation in the digestive lining, a common sign in conditions like inflammatory bowel disease. Conversely, if the stool itself is black, sticky, and tarry (melena), the blood is generally coming from the upper GI tract, such as the stomach or small intestine, where it has been digested.
It is important to visually distinguish true blood clots from other items that can mimic their appearance. Certain foods, like beets, red food coloring, or tomato skins, can pass through the digestive system undigested and may be mistaken for blood or clots. Simple blood streaking or liquid blood on the toilet paper or in the bowl is often associated with minor issues like hemorrhoids or anal fissures. A true blood clot will possess a distinct, thick, and congealed texture, differentiating it from simple red-tinged stool or bright red liquid.
Underlying Conditions Causing Clotted Bleeding
The formation of a blood clot in the stool signals a bleed that is often significant or rapid enough that the blood had time to coagulate before being passed. Bleeding that results in bright red or maroon clots typically originates in the lower digestive tract, where conditions causing rapid blood loss are common. Diverticular disease is one of the most frequent causes of substantial lower GI bleeding, where small pouches (diverticula) in the colon wall can rupture and bleed profusely. This bleeding is often painless but can produce a large amount of clotted blood.
Other serious sources of clotted bleeding include inflammatory bowel diseases (IBD), such as ulcerative colitis and Crohn’s disease, which cause inflammation and ulceration of the intestinal lining. This inflammation can lead to bleeding that is sometimes mixed with mucus and forms clots. Angiodysplasia, a condition involving fragile and enlarged small blood vessels in the GI tract, is another common cause, particularly in older adults, and can result in recurrent, heavy, clotted bleeding.
While upper GI bleeding from conditions like peptic ulcers usually results in black, tarry stool due to the blood being partially digested, a very rapid or massive hemorrhage from the upper GI tract can sometimes lead to the passage of dark red or maroon clots. Severe internal hemorrhoids can also occasionally lead to the formation of small clots when the bleeding is heavy. Colorectal cancer can also cause bleeding, and the appearance of the blood may vary from bright red clots to darker blood mixed with mucus, depending on the tumor’s location.
Recognizing Emergency Symptoms and When to Contact a Doctor
Any instance of blood clots in the stool requires follow-up with a healthcare provider, but certain associated symptoms indicate a medical emergency that requires immediate attention. Signs of significant blood loss or shock, such as feeling dizzy, faint, or light-headed, necessitate an immediate trip to the emergency room. A rapid heart rate, cold and clammy skin, or confusion also signal the need for emergency medical care, as these symptoms can indicate dangerously low blood pressure resulting from acute hemorrhage.
If a person passes a massive volume of blood or clots, enough to visibly turn the toilet water red, emergency medical services should be contacted immediately. Similarly, if the clotted bleeding is accompanied by severe, increasing abdominal pain, a high fever, or persistent vomiting, it suggests a severe underlying condition, such as a serious infection or perforation. For isolated, smaller instances of blood clots without any severe systemic symptoms, a prompt appointment with a primary care physician or a gastroenterologist is necessary. A medical evaluation, typically involving tests like a colonoscopy, is required to definitively diagnose the source of the bleeding and ensure any serious causes are addressed.