LGIB is common is the elderly than in younger people because diverticulosis and malingant of colon are more common in these groups.

Causes of LGIB

• Colitis- Ischemic colitis, ulcerative colitis, radiation induced colitis
• Infection colitis with E- coli, shigella, C. difficle, Campylobacter jejuni
• Non infectious colitis (idiopathic) Like Crohns or ulcerative colitis
• Anorectal disease- hemorrhoids, fissures and fistulas
• Diverticular disease- diverticulosis, diverticulitis
• HIV related opportunistic infection- CMV colitis, Kaposi sarcoma and lymphoma
• Drug induced bleeding- Aspirin and anticoagulants
• Vascular- Angiodyplasia, polyarteritis nodosa, Wegener’s granulomatosis, and aortocolonic fistulas
• General causes: Salicylates, alchohol, liver failure, renal failure, Ingestion of steroids and NSAID's.
• Small intestinal causes: Intussusceptions and Meckel’s diverticulum
• Neoplasm- Colon cancer, postpolypectomty bleeding 

Signs and symptoms

• Rectal bleeding
• Blood in the stools
• Blood on the toilet paper
• Pallor
• Shortness of breathe
• Weakness 

Tests and diagnosis

• Complete blood count
• Serum electrolytes
• Renal function test (blood urea and serum creatinine)
• Coagulation profile (Prothrombin time and INR)
• Colonoscopy
• Radionuclide Imaging
• Angiography
• Upper GI endoscopy and enteroscopy 

Treatment

Medication: Posterior pituitary hormones – Vasopressin and Terlipressin

Modern endoscopic techniques such as injection sclerotherapy, thermo coagulation and laser coagulation seem to be effective in achieving hemostasis and avoiding precarious surgery.

Indications for surgery 

• Persistent hemodynamic instability with active bleeding
• Persistent, recurrent bleeding
• Transfusion of more than 4 units packed red blood cells