Rectal bleeding is a symptom where blood is passed out of the rectum. The blood is usually fresh and referred to as hematochezia, however if the blood is maroon in color, meaning that it is already clotted, it is called melena. Normally, the source of blood is an opening or cut within the lower gastrointestinal tract. It is a common ailment that is referred to emergency departments.
The amount of blood can be small and detected only in the laboratory, or it can be massive and cause significant systemic symptoms. Rectal bleeding is often a symptom of an underlying condition and it must always be investigated.
Rectal bleeding is a common condition reported by about 15% of the population according to some studies. About 90% of the rectal bleeding cases are caused by lower gastrointestinal bleeding. Most rectal bleeding comes from the colon, rectum, or anus.
There are many causes of rectal bleeding and it is often a symptom of a particular disease. It can be a symptom of hemorrhoids, anal fissure, foreign bodies, intestinal tumors, polyps, food poisoning, Crohn's disease, infectious diarrhea, inflammatory bowel disease, diverticulitis, ulcerative colitis, various ulcers, and more serious conditions such as colon and anal dysplasia and cancer.
Independently of the causes, having rectal bleeding is a reason to seek consultation by your doctor.
Symptoms you may experience with rectal bleeding are:
- Dark tarry stools, but it may happen if the person consumed dark-colored food previously.
- Visibly fresh blood in the stool that can be little or massive and continuous (an emergency).
- Bloody smear from wiping after defecating.
- Maroon colored discharge in anus.
- Paleness and anemia
Visible blood is often enough to prompt the doctor to perform tests in order to determine the origin of the bleeding. Physical examination is done by the doctor to look around the structures of the rectum for possible hemorrhoids.
With so many possible causes of rectal bleeding, differential diagnosis is necessary to rule out other causes. The primary tests include a stool exam to examine any hidden fecal bleeding, search for rectal tissue and to look for parasites. Blood tests are ordered to look for the levels of hemoglobin, hematocrit, platelets and to find any markers of the possible cause. Imaging exams such as x-ray, computerized tomography (CT) scans and sigmoidoscopy or colonoscopy procedures might be useful to inspect for sources of internal bleeding.
The main goal of rectal bleeding treatment is to address the underlying cause, which can be as mild as hemorrhoids, parasitism and ulcer to serious as cancer and intestinal perforation (IV). However, patients should always be checked first for significant blood loss and emergently treated for this symptom. It may be treated at home or it might be necessary for the person to be hospitalized and undergo a surgery.
Blood clotting drugs like tranexamic acid, might be used to help manage the bleeding in severe or chronic cases, however these are not usually advocated by doctors because they may mask the origin of the condition, leaving it undetected and untreated. If there is massive bleeding, intravenous fluids are given as first aid until blood typing and cross-matching has been completed for immediate blood transfusion.
If the cause is an active ulcer, antacid agents are administered. Bleeding caused by intestinal infection (as in enterocolitis) is managed with antibiotics in order to destroy the bacteria and protozoans that are possible agents of infection. However, in cases of intestinal tumors, the malignant growth is normally resected via surgery because intestinal malignant tumors spread rapidly.
The prognosis of rectal bleeding depends on the cause. If the cause is ulcers and parasites, the prognostic is generally good when the patient follows the treatment plan closely. Most intestinal infections can be easily managed by antibiotics.
The prognosis of malignant causes can be moderate to bad, depending on the extent of metastasis. In cases of colon cancer, the prognosis is usually bad because rectal bleeding is usually a late sign and often shows when the disease is in its advanced stages.
You can prevent some causes of rectal bleeding by having a diet rich in fiber to prevent constipation. Diverticulitis and hemorrhoids may be prevented by avoiding excessive straining which can damage the tissues in the rectum and cause bleeding.
Individuals with rectal bleeding must consult their physician immediately to identify and treat the underlying condition quickly. Seek immediate (emergency) medical help if significant blood loss is occurring. Many people tend to ignore or dismiss rectal bleeding as a minor symptom. This behavior is dangerous and may lead to development of advanced and untreatable conditions. It is not a normal occurrence, and if the condition is left untreated it can cause death.
Research directed to rectal bleeding involves population-based studies for the study of patterns of behavior towards rectal bleeding and single-case studies that present uncommon causes for this condition. Research is also directed to investigate rectal bleeding associated with medical devices, such as fecal-collecting devices.