Digestive System Anatomy Quiz

Anatomy of the Intestines

• Small intestine divided into three parts:
  • Duodenum: connects to pylorus, approximately 10 inches long.
  • Jejunum: approximately 8 feet in length.
  • Ileum: approximately 12 feet long.
• Large intestine, around 5-6 feet long, consists of three parts:
  • Cecum
  • Colon: includes ascending, transverse, descending, and sigmoid sections
  • Rectum

Bowel/Intestinal Obstruction

• Intestinal obstruction prevents movement of contents through the GI tract, classified as:
  • Small Bowel Obstruction (SBO): more common (75% cases); often treated conservatively.
  • Large Bowel Obstruction (LBO): less common (25% cases); usually requires surgical intervention.

Causes of Obstructions

• SBO:
  • Adhesions, malignancy, hernia, volvulus, intussusception, gallstones.
• LBO:
  • Incarcerated hernia, strictures, diverticular disease, benign polyps.

Types of Obstruction

• Mechanical: Physical blockage caused by:
  • Adhesions, strangulated hernias, strictures, tumors, fecal impaction.
• Non-mechanical: Reduced or absent peristalsis, often due to:
  • Post-surgery complications, peritoneal irritation, or intestinal ischemia.

Clinical Manifestations of Obstruction

• Symptoms linked to mucosal damage include:
  • Diarrhea (foul-smelling, light-colored, frothy), steatorrhea, flatulence, weight loss, and weakness.
  • Severe cases include abdominal pain and increased bleeding tendencies.
• Atypical symptoms also include anemia, dental enamel defects, osteoporosis, arthritis, peripheral neuropathies, and infertility.

Celiac Disease

• Diagnostics:
  • History and physical examination, endoscopy with biopsy, antibody screening, and lab tests (CBC, electrolytes, coags, LFTs).
• Treatment:
  • Lifelong gluten-free diet, identify and treat malnutrition, dietary consultation, education, support groups, and interdisciplinary management.

Diverticulosis and Diverticulitis

• Diverticula: Small pouches in the GI tract, most common in the colon, prevalent in 30-50% of adults over 60.
• Diverticulosis: Presence of non-inflamed diverticula.
• Diverticulitis: Inflamed or infected diverticula.
• Risk Factors for Diverticulosis: Age, obesity, smoking, low-fiber diet, genetic predisposition, certain medications.

Crohn’s Disease

• Can affect any GI tract area; characterized by "skip" lesions and cobblestone appearance due to deep ulcerations.
• Complications include strictures, abscesses, and fistulas.
• Clinical Manifestations: Diarrhea (less severe than ulcerative colitis), abdominal pain, weight loss, steatorrhea, fever, fatigue, and potential bleeding.

Ulcerative Colitis

• Affects the colon, starting in the rectum and progressing to the cecum; primarily involves mucosal layer.
• Leads to diarrhea and electrolyte loss due to inflammation and impaired absorption.
• Clinical Manifestations:
  • Bloody diarrhea (4-20 stools/day classification), weight loss, abdominal pain, fever, and fatigue.

Complications of Crohn’s & Ulcerative Colitis

• Possible complications include hemorrhage, strictures, perforation, perineal abscesses, fistulas, C. difficile infection, toxic megacolon, and elevated colorectal cancer risk.

Inflammatory Bowel Disease (IBD) Management

• Goals: rest the bowel, control inflammation, treat infection, correct malnutrition, and alleviate stress.
• Treatment:
  • Fluid and electrolyte management, medications, nutritional support, and possible TPN.
• Patient Education:
  • Encourage smaller, frequent meals; family meal engagement; rest periods; importance of adequate nutrition; awareness of medication side effects.