Per rectal (PR) bleeding is a worrying symptom for patients; however it is one of the common symptoms of an underlying condition that can be present anywhere within the intestinal tract. PR bleeding can be categorised in a number of different methods. It can be divided into painless versus painful PR bleeding and fresh versus dark PR bleeding.
PR bleeding can also be defined by how it presents, for example, patients may notice blood on the tissue paper after wiping their bottom, or drops of blood within the bowl of the toilet, or blood mixed within the stool. Each of these is a manifestation of a different condition. For example blood noticed on the tissue paper after painful defecation is seen in anal fissures which can be precipitated by constipation. Fresh painless PR bleeding with blood dripping into the bowl of the toilet is commonly associated with haemorrhoids.
However dark blood mixed within the stool can indicate pathology higher up the intestinal tract, and depending on other symptoms experienced such as weight loss, loss of appetite and age, colorectal tumours or intestinal polyps can be a possibility. Furthermore PR bleeding can be seen in patients with acute diverticulitis and inflammatory bowel disease (i.e. Crohn’s disease and Ulcerative Colitis). Note that PR bleeding is not seen in irritable bowel syndrome. PR bleeding that is associated with diarrhoea is common and can be triggered by food poisoning, termed dysentery, with multiple underlying bacterial aetiologies.
Since PR bleeding can be attributed to an array of conditions, investigations performed will be determined following a detailed history and examination to confirm/exclude the suspected diagnosis, with management dependent on the underlying cause.