Hemorrhoids: This is the most common cause of fresh PR (per rectal) bleeding, especially if the blood is bright red and seen on the toilet paper or in the toilet bowl after a bowel movement. Hemorrhoids are swollen veins in the lowest part of the rectum or anus, which can bleed due to increased pressure.

Anal Fissure: A small tear in the lining of the anus can cause sharp pain and bleeding during and after bowel movements. The blood is usually bright red and may be seen on the stool or toilet paper.
Diverticulosis: This condition involves the formation of small, bulging pouches (diverticula) in the digestive tract. When these pouches bleed, it can lead to fresh PR bleeding, although the blood may be mixed with stool.
Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause inflammation and ulcers in the digestive tract, leading to bleeding. The blood may be mixed with stool and can be accompanied by other symptoms like diarrhea and abdominal pain.

Colorectal Cancer: Although less common, colorectal cancer is a critical diagnosis not to miss. It can cause fresh PR bleeding, especially in older adults or those with a family history of the disease. The bleeding may be mixed with stool or appear as black, tarry stools.
Gastrointestinal Angiodysplasia: These are vascular lesions in the gastrointestinal tract that can cause bleeding. They are more common in older adults and can lead to significant blood loss if not identified and treated.
Infectious Colitis: Certain infections can cause inflammation of the colon, leading to bleeding. Identifying the cause (e.g., bacterial, viral) is crucial for appropriate treatment.

Intussusception: A condition where a part of the intestine slides into an adjacent part, potentially cutting off blood supply and causing bleeding. It's more common in children but can occur in adults, often associated with a lead point like 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 a rare cause of gastrointestinal bleeding and usually presents in childhood.
Vascular Malformations: Abnormal connections between arteries and veins can lead to bleeding. These are rare and may require specialized imaging for diagnosis.