By Dr. Mukesh Kalla, Gastroenterology,

It can be quite intimidating to observe either streaks of maroon or dark red blood in your stool or even droplets of blood with stool. The condition may occur due to several causes. Blood in stool is also known as rectal bleeding or hematochezia. Rectal bleeding, as the term suggests, may be caused due to bleeding in the rectum that lies just above the anus. But the cause of the condition is not just limited to bleeding in rectum. It can happen due to infection in other parts of the gastrointestinal tract as well. The severity of the condition varies from one patient to another. Moderate or severe rectal bleeding can cause excess loss of blood from the body thereby causing decreased blood pressure, weakness, dizziness causing the patient to even faint in serious cases.

So, to control and stop the flow of blood in stool, treatment is a must. But it is equally necessary to know the causes as the treatment will be determined accordingly. Following are the common causes of blood in stool:

1. Diverticulosis: This is a condition wherein multiple projections grow on the surface of the colon. The inner wall develops weak spots that push outward through the outer wall of the colon. Diverticulosis occurs mainly in older adults. Diverticula have often been a result of constipation that puts pressure on bowel movements and injures the small blood vessels near the outgrowths.
2. Haemorrhoids: They arise mainly from internal haemorrhoids and are very common factors causing bloody stool. The condition mainly affects people in the age group of 45 to 65 years but can also affect people outside that age bracket. The condition is also known as piles and is caused due to excess pressure exerted on the veins in the lower rectum and anus. Haemorrhoids cause discomfort, bleeding and itching in the anus and can be unbearably painful at times.
3. Colonic Ischemia: In this condition, a particular isolated section of the colon suffers tissue damage due to diminished blood flow and therefore receives less oxygen. It may be caused due to very low blood pressure, cholesterol deposits in the blood vessels thereby hindering normal blood flow, certain medical conditions like sickle cell anaemia, lupus, vasculitis or inflamed blood vessels, some medications that cause the blood vessels to constrict, use of drugs like methamphetamine and cocaine etc.
4. Colonic Angiodysplasia: Colonic angiodysplasia is a condition where the blood vessels in the colon undergo degeneration causing bleeding and bloody stools. People who have several abnormal blood vessels in the colon suffer damage and this results in bleeding in the lower gastrointestinal tract.
5. Colorectal Polyps and Cancer: Colorectal polyps are small masses of cells or outgrowths from the colon. They can be both cancerous and non-cancerous. The symptoms are evident only when the polyps have grown considerably large. Colorectal polyps are actually caused due to mutation in genes that trigger cells to keep on dividing even if new cell production is not required.
6. Ulcerative Colitis: This condition is responsible for chronic nature of blood in stool, usually associated with diarrhoea. Now a days with better medicine it is satisfactorily controlled and patient can maintain good symptom free controlled disease for long time.
7. Hemmorrhoides: This condition is usually a result of prolonged constipation , marked by pain less bleed separate from stool. It can easily be treated by endoscopy and larger ones need stapler surgery for cure.
8. Fissure: This disease is marked by blood in stool and associated with hard lumpy stools. Stool softeners and few local medicine with hot shitz bath controls this problem, rarely it needs surgery.
9. Hemmorrhoides: Fissure in Ani Cancer colon Ulcerative colitis/Crohn’s disease( IBD) Diverticulosis AV Malformation Mesenteric ischemia Rarely Portal hypertension Duodenal ulceration bleed

It can be quite intimidating to observe either streaks of maroon or dark red blood in your stool or even droplets of blood with stool. The condition may occur due to several causes. Blood in stool is also known as rectal bleeding or hematochezia. Rectal bleeding, as the term suggests, may be caused due to bleeding in the rectum that lies just above the anus. But the cause of the condition is not just limited to bleeding in rectum. It can happen due to infection in other parts of the gastrointestinal tract as well. The severity of the condition varies from one patient to another. Moderate or severe rectal bleeding can cause excess loss of blood from the body thereby causing decreased blood pressure, weakness, dizziness causing the patient to even faint in serious cases.

So, to control and stop the flow of blood in stool, treatment is a must. But it is equally necessary to know the causes as the treatment will be determined accordingly. Following are the common causes of blood in stool:

1. Diverticulosis: This is a condition wherein multiple projections grow on the surface of the colon. The inner wall develops weak spots that push outward through the outer wall of the colon. Diverticulosis occurs mainly in older adults. Diverticula have often been a result of constipation that puts pressure on bowel movements and injures the small blood vessels near the outgrowths.
2. Haemorrhoids: They arise mainly from internal haemorrhoids and are very common factors causing bloody stool. The condition mainly affects people in the age group of 45 to 65 years but can also affect people outside that age bracket. The condition is also known as piles and is caused due to excess pressure exerted on the veins in the lower rectum and anus. Haemorrhoids cause discomfort, bleeding and itching in the anus and can be unbearably painful at times.
3. Colonic Ischemia: In this condition, a particular isolated section of the colon suffers tissue damage due to diminished blood flow and therefore receives less oxygen. It may be caused due to very low blood pressure, cholesterol deposits in the blood vessels thereby hindering normal blood flow, certain medical conditions like sickle cell anaemia, lupus, vasculitis or inflamed blood vessels, some medications that cause the blood vessels to constrict, use of drugs like methamphetamine and cocaine etc.
4. Colonic Angiodysplasia: Colonic angiodysplasia is a condition where the blood vessels in the colon undergo degeneration causing bleeding and bloody stools. People who have several abnormal blood vessels in the colon suffer damage and this results in bleeding in the lower gastrointestinal tract.
5. Colorectal Polyps and Cancer: Colorectal polyps are small masses of cells or outgrowths from the colon. They can be both cancerous and non-cancerous. The symptoms are evident only when the polyps have grown considerably large. Colorectal polyps are actually caused due to mutation in genes that trigger cells to keep on dividing even if new cell production is not required.
6. Ulcerative Colitis: This condition is responsible for chronic nature of blood in stool, usually associated with diarrhoea. Now a days with better medicine it is satisfactorily controlled and patient can maintain good symptom free controlled disease for long time.
7. Hemmorrhoides: This condition is usually a result of prolonged constipation , marked by pain less bleed separate from stool. It can easily be treated by endoscopy and larger ones need stapler surgery for cure.
8. Fissure: This disease is marked by blood in stool and associated with hard lumpy stools. Stool softeners and few local medicine with hot shitz bath controls this problem, rarely it needs surgery.
9. Hemmorrhoides: Fissure in Ani Cancer colon Ulcerative colitis/Crohn’s disease( IBD) Diverticulosis AV Malformation Mesenteric ischemia Rarely Portal hypertension Duodenal ulceration bleed

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