Rectal bleeding is when there is a discharge of blood from the bottom, usually when a patient goes to the toilet. It is a typical sign of piles (haemorrhoids) or a small tear (anal fissure) in the skin of your anus. It is usually noticed as bright-red blood on toilet paper or a few droplets of blood that turn the water in the toilet pink.
The primary symptom is the bleeding which can either be bright red or dark red. It can sometimes be mixed with the stool or separate from the stool. The patient can also sometimes experience a change of bowel habits as a result of rectal bleeding.
If the blood is particularly dark in colour and sticky, the bleeding may have occurred higher up in the digestive system. This can lead to the faeces turning black or plum-coloured (known as melena), which requires urgent medical treatment.
There are a wide range of causes of rectal bleeding. The most common causes include:
- haemorrhoids, which involves swollen blood vessels in and around the rectum, which can bleed when the patient has a bowel movement, and cause itchiness around the anus;
- anal fissure, which is a small tear in the skin of the anus causing pain and bright red blood;
- anal fistula, which involves a small channel developing between the end of the bowel, known as the anal canal or back passage, and the skin near the anus;
- diverticulosis, which is a bulging pouch that forms on the wall of the intestine leading to weakened blood vessels that can burst and cause sudden, painless bleeding;
- gastroenteritis, which is a viral or bacterial infection of the stomach and bowel, causing diarrhoea containing traces of blood and mucus, as well as vomiting and stomach cramps.
Other causes can include ischemic colitis (colon inflammation caused by reduced blood flow), proctitis (inflammation of the rectum), pseudomembranous colitis (colon inflammation caused by an infection), radiation therapy, and solitary rectal ulcer syndrome (a sore on the wall of the rectum). There are some serious underlying conditions that are less common causes of rectal bleedings, such as colon and rectal cancers, and inflammatory bowel disease, such as Crohn's disease and ulcerative colitis.
The doctor will first ask the patient a series of questions and may conduct a physical examination of the rectum. This involves putting a gloved finger inside the bottom (rectum). It is a painless procedure and will usually takes one to five minutes, depending on whether your GP finds anything unusual. The doctor may then take a stool sample and test for blood.
The patient may also take a blood test to check to see if they are anaemic. The results will give the doctor an idea of the extent of the bleeding and how chronic it may be. The patient may also be referred to a hospital or specialist clinic if further examinations and tests are needed.
If the patient has bleeding in the digestive tract, they may undergo an endoscopy. This procedure allows the doctor to see exactly where the bleeding is happening. In some cases, the doctor can use the endoscope to treat the cause of bleeding. It is a thin, flexible tool that can be inserted through the mouth or rectum to see the areas of concern and take a tissue sample, or biopsy, if required.
Several other procedures can be used to find the source of bleeding, including:
- X-rays, during which the patient may either drink or have barium-containing fluid placed through the rectum, then an X-ray is used to look for any unusual signs, and barium will light up on the imaging test;
- Angiography, which involves injecting a dye into a vein before the patient has a CT scan or MRI as the dye helps to show where the trouble is and can be used to administer medicine to stop the bleeding;
- and radionuclide scanning, which can help to find sites of bleeding, especially in the lower digestive tract, and involves being given a small amount of harmless radioactive material before the doctor uses a special camera to take pictures of the organs.
The treatment is entirely reliant on the nature and cause of the bleeding. Sometimes patients can simply manage their self-care measures to treat rectal bleeding, such as rectal ointments and suppositories, which can be bought over-the-counter without a prescription.
There is the specific telescopic examinations that can be undertaken to look into rectal bleeding, some of which take place in the clinic, or a more invasive endoscopy using the flexible sigmoidoscopy or colonoscopy. If the upper digestive tract is bleeding, the doctor may be able to control it by injecting chemicals directly into the problem area, using an endoscope to guide the needle.
A doctor can also use heat to treat (or "cauterize") an area that is bleeding and surrounding tissue through the endoscope, or place a "clip on a bleeding blood vessel. Once the bleeding is under control, the patient may also need to take medicine to ensure the bleeding does not return.
Those techniques aren't always enough and sometimes the patient may need surgery. This will depend on the cause and condition. Severe haemorrhoids will have haemorrhoidectomy, fissures may need ointments or treatments. More serious diseases of the bowel will be treated on their merits.
There are two key benefits. Firstly, a diagnosis will essentially exclude the possibility of serious diseases. Secondly, the treatment will manage upsetting and distressing symptoms, particularly if it becomes more persistent and stains the patient's clothes.
Since the vast majority of bleeding comes from haemorrhoids and anal conditions, the best way to look after the digestive system is to eat plenty of fibre and maintain a mixed diet. Patients should also avoid straining when on the toilet.
Patients should also ensure they drink 8-10 glasses of water per day, bathe or shower daily to cleanse the skin around the anus, avoid sitting on the toilet for too long, apply ice packs to the affected area to decrease pain, and avoid drinking excessive amounts of alcohol, as that can contribute to dehydration, a primary cause of constipation. Patients may also consider taking a sitz bath, which is a warm water bath with water just deep enough to cover the hips and buttocks, and can help relieve some symptoms of itching, pain and discomfort of haemorrhoids.
The treatments for rectal bleeding are very effective so once the cause has been identified then it is very likely that they will solve the bleeding. It is fair to say that for conditions like haemorrhoids, repeated treatment may be necessary over a patient's lifetime, but that control can be achieved relatively easily in most cases. Obviously, if the patient has a more serious GI disease then that can be treated with the same merits and has its own prognosis. The bleeding itself is only a symptom, not a diagnosis.