Differential Diagnosis for Massive Lower GIT Bleeding in a 67 y.o Male

Single Most Likely Diagnosis

• B. Diverticulosis: This is the most common cause of massive lower gastrointestinal bleeding in adults, especially in the elderly. The patient's age and history of chronic constipation, which can increase intraluminal pressure and contribute to diverticula formation, support this diagnosis.

Other Likely Diagnoses

• A. Angiodysplasia: This condition is more common in the elderly and can cause significant lower GI bleeding. The patient's age and the fact that angiodysplasia often presents with sudden onset of bleeding without other symptoms make it a plausible option.
• C. Colonic cancer: Although less common than diverticulosis as a cause of massive lower GI bleeding, colonic cancer is still a significant consideration, especially given the patient's age, which puts him in a higher risk category for colorectal cancer.
• E. Haemorrhoids: While typically associated with smaller amounts of bleeding, in some cases, especially if the hemorrhoids are large or thrombosed, they can cause more significant bleeding.

Do Not Miss Diagnoses

• D. Peptic ulcer disease: Although more commonly associated with upper GI bleeding, peptic ulcers can occasionally cause lower GI bleeding, especially if the ulcer is located in the duodenum near the ligament of Treitz. Given the patient's history of taking Clodrel (an antiplatelet agent), which can increase the risk of bleeding from ulcers, this diagnosis should not be overlooked.
• Ischemic colitis or other vascular events: These conditions can present with sudden onset of abdominal pain and bleeding. Given the patient's history of ischemic heart disease (IHD) and use of antiplatelet therapy, vascular events should be considered.

Rare Diagnoses

• Intussusception: A condition where a part of the intestine telescopes into another part, which can cause bowel obstruction and bleeding. It's rare in adults but can be associated with a lead point such as a tumor.
• Meckel's diverticulum: A congenital anomaly of the small intestine that can cause bleeding due to the presence of ectopic gastric mucosa. It's more common in younger patients but can present at any age.
• Inflammatory bowel disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause significant lower GI bleeding. While they are more chronic in nature, acute presentations can occur, especially in older adults where the diagnosis might have been missed or the condition was previously mild.