Disorders of the Colon (High-Yield) PDF

WE MAKE DOCTORS Pathology of the Colon (High-yield) Rodrigo Vivar Barragán Index 1. Diverticular Disease (Diverticulosis and Diverticulitis) 2. Inflammatory Bowel Disease (Crohn's Disease and Ulcerative Colitis) 3. Colorectal Cancer (Adenocarcinoma and Squamous Cell Carcinoma) 4. Preventi...

WE MAKE DOCTORS Pathology of the Colon (High-yield) Rodrigo Vivar Barragán Index 1. Diverticular Disease (Diverticulosis and Diverticulitis) 2. Inflammatory Bowel Disease (Crohn's Disease and Ulcerative Colitis) 3. Colorectal Cancer (Adenocarcinoma and Squamous Cell Carcinoma) 4. Prevention and Early Detection 5. Psychosocial Impact 6. Recent Advances Objectives 01 02 03 04 05 06 Understand the Learn the diagnostic Comprehend the Recognize the risk Appreciate the Stay informed about epidemiology, approaches and characteristics and factors, diagnosis, importance of recent advances in pathogenesis, and treatment options for management of and treatment prevention, early treatment and clinical diverticular disease. inflammatory bowel strategies for detection, and the research. manifestations of diseases. colorectal cancer. psychosocial impact diverticular disease. of these diseases. Diverticular Disease: Definition and Epidemiology Diverticulosis: Presence of diverticula in the colonic wall. Prevalence: Increases with age; 30% of people over 50, 50-70% of those over 80. More common in developed countries due to dietary factors. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Diverticular Disease: Pathogenesis Low-fiber diet leads to altered intestinal motility and increased intraluminal pressure. Other risk factors: Obesity, sedentary lifestyle, advanced age. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Diverticular Disease: Definition and Epidemiology Diverticular Disease: Clinical Manifestations Most are asymptomatic. Symptomatic cases: Intermittent abdominal pain (left lower quadrant), bloating, changes in bowel habits. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Diverticular Disease: Diagnosis Colonoscopy: Direct visualization of diverticula. CT scan: Useful for evaluating complications. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Diverticular Disease: Complications Diverticular bleeding: Painless hematochezia. Fistula formation: Abnormal connections between colon and other organs. Perforation: Can lead to peritonitis. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Diverticulitis: Definition and Pathogenesis Inflammation and infection of diverticula. Caused by fecal impaction leading to local inflammation and perforations. Diverticulitis: Classification Hinchey I: Pericolic or mesenteric abscess. Hinchey II: Pelvic abscess. Hinchey III: Purulent peritonitis. Hinchey IV: Fecal peritonitis. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Diverticulitis: Classification Le, T., Bhushan, V., & Sochat, M. (2022). First Aid for the USMLE Step 1 2022 (32nd ed.). McGraw-Hill Education. Diverticulitis: Clinical Manifestations Abdominal pain (left lower quadrant), fever, leukocytosis. Changes in bowel habits: Diarrhea or constipation. Nausea, vomiting, dysuria if fistulas are present. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Diverticulitis: Diagnosis Clinical history and physical examination. Laboratory tests: Leukocytosis. CT scan: Gold standard for diagnosing acute diverticulitis. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Diverticulitis: Treatment Medical management: Broad-spectrum antibiotics, liquid or low- residue diet, analgesics. Surgical management: Perforation, non-drainable abscesses, intestinal obstruction, recurrent diverticulitis. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Summary: Diverticular Disease Diverticulosis: Presence of diverticula, usually asymptomatic. Diverticulitis: Inflammation and infection of diverticula, requiring medical or surgical management. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Inflammatory Bowel Disease: Crohn's Disease Chronic inflammatory condition affecting any part of the GI tract. Most common in terminal ileum and colon. Higher incidence in developed countries. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Crohn's Disease: Pathogenesis Multifactorial etiology: Genetic, immunologic, environmental factors. Genetic: Mutations in NOD2/CARD15 gene. Immunologic: Abnormal immune response against intestinal antigens. Environmental: Smoking, Westernized diet, antibiotic use in childhood. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Crohn's Disease: Clinical Manifestations Symptoms depend on location and severity: Abdominal pain, chronic diarrhea, weight loss, fever. Perianal involvement: Fistulas, abscesses. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Crohn's Disease: Diagnosis Combination of endoscopy with biopsy, imaging studies (CT, MRI). Serological markers: ASCA (anti-Saccharomyces cerevisiae antibodies). Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Crohn's Disease: Complications Intestinal stenosis, fistulas, abscesses, malabsorption, nutritional deficiencies. Increased risk of colorectal cancer. Crohn's Disease: Treatment Pharmacologic: Aminosalicylates, corticosteroids, immunomodulators, biologics. Surgical: Indicated for complications: Refractory stenosis, fistulas, severe perianal disease. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Feldman, M., Friedman, L. S., & Brandt, L. J. (Eds.). (2020). Sleisenger and Fordtran's Gastrointestinal and Liver Disease: Pathophysiology, Diagnosis, Management (11th ed.). Philadelphia, PA: Elsevier Saunders. Inflammatory Bowel Disease: Ulcerative Colitis Chronic inflammatory disease of the colon. Always affects the rectum, can extend proximally in a continuous manner. Similar incidence to Crohn's disease in developed countries. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Le, T., Bhushan, V., & Sochat, M. (2022). First Aid for the USMLE Step 1 2022 (32nd ed.). McGraw-Hill Education. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Ulcerative Colitis: Pathogenesis COMBINATION OF GENETIC, IMMUNOLOGIC: ABNORMAL INTESTINAL MICROBIOTA: RISK FACTORS: FAMILY IMMUNOLOGICAL, AND IMMUNE RESPONSE AGAINST ALTERATIONS IN BACTERIAL HISTORY OF IBD, DIET, ENVIRONMENTAL FACTORS. INTESTINAL MICROBIOTA. COMPOSITION OF THE GUT. ENVIRONMENTAL FACTORS. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Ulcerative Colitis: Clinical Manifestations Extraintestinal symptoms: Arthritis, uveitis, primary sclerosing cholangitis. Feldman, M., Friedman, L. S., & Brandt, L. J. (Eds.). (2020). Sleisenger and Fordtran's Gastrointestinal and Liver Disease: Pathophysiology, Diagnosis, Management (11th ed.). Philadelphia, PA: Elsevier Saunders. Ulcerative Colitis: Diagnosis Colonoscopy with biopsy: Continuous and superficial inflammation of the colon. Histopathology: Cryptitis, crypt abscesses. Imaging studies: Assess extent and severity. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Ulcerative Colitis: Complications Toxic megacolon, colonic perforation, massive hemorrhage. Increased risk of colorectal cancer. Feldman, M., Friedman, L. S., & Brandt, L. J. (Eds.). (2020). Sleisenger and Fordtran's Gastrointestinal and Liver Disease: Pathophysiology, Diagnosis, Management (11th ed.). Philadelphia, PA: Elsevier Saunders. Ulcerative Colitis: Treatment Pharmacologic: Aminosalicylates, corticosteroids, immunomodulators, biologics. Surgical: Colectomy in refractory cases or severe complications. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Summary: Inflammatory Bowel Disease Crohn's Disease: Chronic inflammation, affects any part of the GI tract. Ulcerative Colitis: Chronic inflammation, affects only the colon. Both require pharmacologic and sometimes surgical treatment. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Le, T., Bhushan, V., & Sochat, M. (2022). First Aid for the USMLE Step 1 2022 (32nd ed.). McGraw-Hill Education. Le, T., Bhushan, V., & Sochat, M. (2022). First Aid for the USMLE Step 1 2022 (32nd ed.). McGraw-Hill Education. Colorectal Cancer: Adenocarcinoma Most common type of colorectal cancer. Higher incidence in developed countries. Risk factors: Family history, hereditary syndromes, high-fat diet, smoking, alcohol. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Colorectal Cancer: Adenocarcinoma AMBOSS. (2021). Adenocarcinoma of the Colon. Retrieved from https://next.amboss.com/us/article/TS06_2?q=adenocarcinoma+colon&m=D4b1lF Adenocarcinoma: Pathogenesis and Progression Adenoma-carcinoma sequence: Adenomatous polyps undergo malignant transformation. Genetic mutations: APC, KRAS, TP53. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Adenocarcinoma: Pathogenesis and Progression Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Adenocarcinoma: Pathogenesis and Progression Le, T., Bhushan, V., & Sochat, M. (2022). First Aid for the USMLE Step 1 2022 (32nd ed.). McGraw-Hill Education. Adenocarcinoma: Pathogenesis and Progression AMBOSS. (2021). Adenocarcinoma of the Colon. Retrieved from https://next.amboss.com/us/article/TS06_2?q=adenocarcinoma+colon&m=D4b1lF Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Adenocarcinoma: Clinical Manifestations Initial symptoms: Changes in bowel habits, hematochezia, iron-deficiency anemia, weight loss. Advanced symptoms: Intestinal obstruction, abdominal pain. Feldman, M., Friedman, L. S., & Brandt, L. J. (Eds.). (2020). Sleisenger and Fordtran's Gastrointestinal and Liver Disease: Pathophysiology, Diagnosis, Management (11th ed.). Philadelphia, PA: Elsevier Saunders. Adenocarcinoma: Diagnosis Colonoscopy with biopsy. Tumor markers: Carcinoembryonic antigen (CEA). Imaging: CT, MRI, PET for staging. Feldman, M., Friedman, L. S., & Brandt, L. J. (Eds.). (2020). Sleisenger and Fordtran's Gastrointestinal and Liver Disease: Pathophysiology, Diagnosis, Management (11th ed.). Philadelphia, PA: Elsevier Saunders. Adenocarcinoma: Staging and Classification TNM system: Tumor invasion (T), lymph node involvement (N), metastasis (M). Clinical stages I to IV. Feldman, M., Friedman, L. S., & Brandt, L. J. (Eds.). (2020). Sleisenger and Fordtran's Gastrointestinal and Liver Disease: Pathophysiology, Diagnosis, Management (11th ed.). Philadelphia, PA: Elsevier Saunders. Adenocarcinoma: Treatment Surgery: Segmental resection, total colectomy. Chemotherapy: Advanced stages, adjuvant post-surgery. Radiotherapy: Mainly for rectal cancer. Targeted therapies: Bevacizumab, cetuximab. Feldman, M., Friedman, L. S., & Brandt, L. J. (Eds.). (2020). Sleisenger and Fordtran's Gastrointestinal and Liver Disease: Pathophysiology, Diagnosis, Management (11th ed.). Philadelphia, PA: Elsevier Saunders. Adenocarcinoma: Prognosis and Follow-Up Prognosis depends on stage at diagnosis: Better outcomes in early stages. Follow-up: Regular colonoscopies, monitoring tumor markers. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Colorectal Cancer: Squamous Cell Carcinoma Less common than adenocarcinoma. Risk factors: HPV infection, chronic inflammatory conditions. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Squamous Cell Carcinoma: Clinical Manifestations Symptoms: Anal pain, rectal bleeding, palpable anal masses. Presentation varies with tumor location and extent. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Squamous Cell Carcinoma: Diagnosis Visualization via anoscopy, biopsy, imaging studies. Histological characteristics distinctive of squamous cell carcinoma. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Squamous Cell Carcinoma: Treatment Surgery, chemotherapy, radiotherapy. Response to treatment varies by stage and tumor characteristics. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Squamous Cell Carcinoma: Prognosis Generally worse prognosis than adenocarcinoma. Influenced by stage at diagnosis, response to treatment. Factors: Local invasion, lymph node involvement. Robbins & Cotran Pathologic Basis of Disease, 10th Edition, Chapter 17, (753-822) Transversal Themes: Prevention and Early Detection Early detection through colonoscopy crucial for preventing colorectal cancer. Colonoscopy: Identification and removal of precancerous polyps. Transversal Themes: Psychosocial Impact Colon diseases significantly impact patients' quality of life. Multidisciplinary management: Psychological support for stress, anxiety, depression. Transversal Themes: Recent Advances New biological and targeted therapies, ongoing research on gut microbiota. Role of biomarkers in personalized diagnosis and treatment. Clinical trials exploring new treatment options and management strategies. Summary: Colorectal Cancer Adenocarcinoma: Most common type, treated with surgery, chemotherapy, radiotherapy. Squamous Cell Carcinoma: Less common, influenced by HPV infection, treated with surgery, chemotherapy, radiotherapy. Summary: Transversal Themes Prevention and early detection: Crucial for colorectal cancer. Psychosocial impact: Multidisciplinary management essential. Recent advances: Biological therapies, gut microbiota research, biomarkers.