Blood in stool can be an alarming symptom. Though it warrants attention, it doesn’t always indicate a severe underlying issue. Understanding its potential causes and when to seek medical advice is important.
Blood in Stool and Cancer Risk
When blood appears in stool, cancer is often a concern. While it can be a symptom of colorectal cancer, it’s far more frequently linked to other, less serious conditions. The presence of blood does not automatically mean cancer; benign conditions account for the vast majority of cases.
The likelihood of blood in stool being caused by cancer is lower than from non-cancerous issues. For instance, hemorrhoids or anal fissures are more prevalent causes of visible blood. Any instance of blood in stool warrants medical evaluation to pinpoint the exact cause.
Common Non-Cancerous Causes
Many common conditions can lead to blood in stool, often less serious than cancer. Hemorrhoids, swollen veins in the rectum or anus, are a frequent cause of bright red blood, especially after a bowel movement. Anal fissures, small tears in the lining of the anus, can also cause bleeding. Both conditions are often associated with straining during defecation.
Diverticulitis, an inflammation or infection of small pouches in the colon lining, is another common source of bleeding. Inflammatory bowel disease (IBD), encompassing Crohn’s disease and ulcerative colitis, involves chronic inflammation of the digestive tract. It can cause bloody diarrhea, abdominal pain, and weight loss.
Peptic ulcers, open sores on the stomach or duodenum lining, can also bleed. This bleeding might manifest as black, tarry stools (melena) if the blood has been digested. Infections caused by bacteria or viruses can irritate the digestive tract, leading to inflammation and sometimes bloody stools. Certain medications, like nonsteroidal anti-inflammatory drugs (NSAIDs) or blood thinners, can also cause gastrointestinal bleeding.
Recognizing Different Types of Blood
Blood appearance offers clues about its origin. Bright red blood, often seen on toilet paper or dripping into the toilet bowl, indicates bleeding from the lower gastrointestinal tract (e.g., anus or rectum). This blood is fresh and has not been significantly altered by digestive enzymes. Common causes include hemorrhoids or anal fissures.
Dark red or maroon-colored blood, mixed with stool, often suggests bleeding from higher in the colon or small intestine. This darker color indicates the blood has traveled some distance, undergoing partial digestion. Conditions like diverticulitis or inflammatory bowel disease can present with this type of bleeding. Black, tarry stools (melena) usually point to bleeding from the upper gastrointestinal tract, such as the stomach or esophagus. Their dark, sticky appearance is due to hemoglobin being chemically altered by digestive acids.
Additionally, blood can be present in stool but not visible to the naked eye; this is referred to as occult blood. This hidden blood is often detected through specific laboratory tests. While different appearances can suggest different sources, self-diagnosis based solely on blood color is not reliable. A medical professional must conduct proper evaluation.
When to Seek Medical Advice
Any instance of blood in stool warrants medical evaluation by a healthcare professional. It is important to avoid self-diagnosis or waiting for the symptom to resolve, as the underlying cause could be serious.
Specific scenarios necessitate immediate medical attention. These include large amounts of blood in the stool, feeling dizzy or lightheaded, or experiencing significant weakness. Severe abdominal pain accompanying the bleeding is also a sign to seek urgent care. Persistent blood over several days, or any change in bowel habits associated with the bleeding, should prompt a rapid consultation.
Diagnostic Steps
When a person seeks medical attention for blood in stool, a doctor will begin with a thorough medical history and physical examination. The physical exam may include a digital rectal exam to check for issues like hemorrhoids or masses in the lower rectum. Initial diagnostic steps often involve stool tests, such as a fecal occult blood test (FOBT) or a fecal immunochemical test (FIT). These tests detect hidden blood and guide further investigation.
Blood tests may be ordered for anemia, inflammation, or infection. Endoscopic procedures visualize the digestive tract. A colonoscopy examines the entire colon for bleeding sources, polyps, or other abnormalities. For suspected upper gastrointestinal bleeding, an esophagogastroduodenoscopy (EGD), or upper endoscopy, examines the esophagus, stomach, and duodenum.
In some cases, a sigmoidoscopy may be performed, which examines only the lower part of the colon. Imaging tests, such as a computed tomography (CT) scan, might also be used to identify inflammation, tumors, or other structural issues within the abdomen. The specific diagnostic approach will depend on the patient’s symptoms, medical history, and initial findings from the physical examination and basic tests.