Lecture on Causes of Rectal Bleeding

Introduction

• Presenter: Tom from zero2finals.com
• Educational purpose to help healthcare students prepare for exams
• Not medical advice

Gastrointestinal (GI) Tract Overview

• Blood in the back passage indicates bleeding in GI tract
• GI Tract progression:
  • Mouth → Esophagus → Stomach → Duodenum, Jejunum, Ileum (Small intestine) → Cecum → Ascending, Transverse, Descending, Sigmoid Colon → Rectum → Anus

Blood Color Significance

• Brighter red blood: Lower GI tract bleeding
• Darker blood: Upper GI tract bleeding

Consequence: Anemia

• Result of GI bleeding: Iron deficiency anemia
  • Symptoms: Low hemoglobin, low mean cell volume (microcytic anemia), low ferritin
  • Consider chronic GI bleeding if no other cause is apparent
• Diagnosis: Upper and lower endoscopy

Suspected Cancer Referrals

• Urgent Exclusion of Colorectal Cancer: Rectal bleeding as a red flag
• NICE Guidelines Criteria:
  • Over 50 with unexplained rectal bleeding
  • Under 50 with rectal bleeding + (abdominal pain, iron deficiency anemia, weight loss, change in bowel habit)
  • Over 40 with weight loss + abdominal pain
  • Over 60 with iron deficiency anemia or change in bowel habit
  • Positive fecal immunochemical test (FIT), rectal or abdominal mass

Causes of Fresh, Bright Red Blood

• Indicates issue at the anus:
  • Common Causes: Hemorrhoids, Anal fissure, Trauma, Infections, Anal cancer

Hemorrhoids

• Enlarged anal vascular cushions
  • Associated with: Constipation, straining, pregnancy, obesity, age, increased intra-abdominal pressure
  • Symptoms: Painless bright red bleeding, itching, soft lump
  • Diagnosis: Digital rectal exam, Proctoscopy

Anal Fissures

• Small tears in the anal mucosa
  • Symptoms: Bright red blood, pain during bowel movement
  • Management: Laxatives, analgesia, topical anesthetics, GTN ointment (causes headaches)

Blood Mixed with Stools

• Higher in large bowel
  • Causes: Gastroenteritis, diverticular disease, inflammatory bowel disease, angiodysplasia, polyps, colorectal cancer, beetroot consumption

Gastroenteritis

• Inflammation/infection of GI tract
  • Causes: Campylobacter, E. coli, Shigella, Salmonella, Yersinia
  • Symptoms: Abdominal cramps, diarrhea, vomiting, fever, rectal bleeding
  • Diagnosis: Stool sample for microscopy, culture, antibiotic sensitivity
  • Management: Supportive, antibiotics if specific cause known

Diverticular Disease

• Diverticulum: Pouch in bowel wall
• Diverticulosis: Presence of diverticula without inflammation
  • Diverticulitis: Inflammation/infection of diverticula
  • Symptoms: Pain, fever, diarrhea, nausea, vomiting, rectal bleeding, palpable abdominal mass
  • Management: Antibiotics, analgesia, limited oral intake, possible surgery

Inflammatory Bowel Disease (IBD)

• Types: Ulcerative colitis, Crohn’s disease
  • Symptoms: Diarrhea, abdominal pain, blood in stools, weight loss
  • Key Test: Fecal calprotectin
  • Diagnosis: Endoscopy and biopsy
  • Management: Steroids, immunosuppressants

Angiodysplasia

• Patches of dilated/abnormal small blood vessels in bowel wall
  • Symptoms: Rectal bleeding, iron deficiency anemia
  • Diagnosis: Endoscopy
  • Management: Treatment during endoscopy

Intestinal Polyps

• Growths in bowel lining
  • Symptoms: Often asymptomatic, may cause rectal bleeding
  • Diagnosis/Treatment: Colonoscopy

Colorectal Cancer

• 4th most prevalent cancer in the UK
  • Red Flags: Change in bowel habit, unexplained weight loss, rectal bleeding, unexplained abdominal pain, iron deficiency anemia, abdominal/rectal mass
  • Tests: FIT, colonoscopy, staging CT scan, CEA tumor marker
  • Management: Surgery, chemotherapy, radiotherapy, palliative care

Causes of Black Stools

• Molena: Black, tar-like, offensive-smelling stools
  • Causes: Stomach ulcers, cancers, malory-vice tears, esophageal varices
  • Management Mnemonic: ABATED (ABCDE approach, Blood tests, Access, Transfusion, Endoscopy, Drugs)

Risk Factors for Bleeding

• Medications: Aspirin, clopidogrel, ticagrelor, heparin, warfarin, DOACs
• Bleeding Disorders: Thrombocytopenia, von Willebrand disease, hemophilia

Conclusion

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• Video ending