Pathophysiology of Digestive Function #7

Clinical Manifestations of Gastrointestinal Dysfunction

• Anorexia: Lack of appetite despite physiological hunger signals.
• Vomiting: Forceful expulsion of stomach and intestinal contents, often preceded by nausea. Symptoms include hypersalivation and tachycardia.
• Stimuli for Vomiting: Can be triggered by medications, pain, GI irritation, or increased intracranial pressure.
• Projectile Vomiting: Occurs without prior nausea or retching, linked to neurological lesions in the brain stem.
• Nausea: Subjective sensation often related to various conditions.
• Constipation: Marked by infrequent or difficult bowel movements; can be primary (functional, slow transit) or secondary (dietary, medical factors).
• Diarrhea: Characterized by loose, watery stools. Can be acute or persistent with mechanisms involving osmotic, secretory, or motility factors. Associated risks include dehydration and electrolyte imbalance.
• Abdominal Pain: Can be mechanical, inflammatory, or ischemic, frequently indicating tissue injury.
• Gastrointestinal Bleeding: Can occur in upper (esophagus, stomach, duodenum) or lower (jejunum, ileum, colon, rectum) GI tract; severity depends on blood loss rate and amount.

Disorders of Motility

• Dysphagia: Difficulty swallowing due to mechanical obstructions or functional disorders. Symptoms include stabbing pain and regurgitation.
• Gastroesophageal Reflux Disease (GERD): Caused by acid reflux leading to esophagitis; symptoms include heartburn, dysphagia, and chronic cough.
• Hiatal Hernia: Protrusion of stomach through diaphragm; types include sliding, paraesophageal, and mixed; treatment is usually conservative.

Ulcers and Malabsorption

• Gastric Ulcers: Commonly found in the antral region of the stomach; associated with increased mucosal permeability to hydrogen ions.
• Malabsorption Syndromes: Includes maldigestion (chemical digestion failure) and malabsorption (nutrient absorption failure). Vitamin deficiencies may arise from these conditions.

Inflammatory Bowel Disease

• Ulcerative Colitis: Characterized by ulceration of the colonic mucosa, primarily affecting the sigmoid colon and rectum with symptoms of severe diarrhea and cramping. Treatment involves 5-aminosalicylic acid, steroids, or surgery.
• Crohn Disease: Can affect any part of the GI tract presenting with skip lesions and similar symptoms to ulcerative colitis; may cause vitamin B12 deficiency.

Irritable Bowel Syndrome (IBS)

• IBS: Affects bowel habits with symptoms like abdominal pain and bloating; more common in females, often associated with stress. Treatment is symptom-based.

Appendicitis and Obesity

• Appendicitis: Inflammation of the appendix; causes include obstruction and infection, with rebound tenderness as a key symptom.
• Obesity: Defined as body mass index >30, linked to higher mortality and healthcare costs, resulting from caloric intake exceeding expenditure.

Liver Disorders

• Portal Hypertension: High blood pressure in the portal venous system due to resistance, leading to varices and splenomegaly.
• Ascites: Fluid accumulation in the peritoneal cavity, most commonly due to cirrhosis; can cause abdominal distension.
• Hepatic Encephalopathy: Neurological impairment due to liver dysfunction, presenting initially with personality changes and progressing to severe confusion and disorientation.

Cancer of the Gastrointestinal Tract

• Esophageal Cancer: Associated with chronic alcohol use, smoking, and symptoms like chest pain and dysphagia.
• Stomach Cancer: Linked to Helicobacter pylori and lifestyle factors; vague early symptoms followed by significant issues in the later stages.
• Colorectal Cancer: Linked to genetic factors and polyps; symptoms vary based on lesion location.

Disorders of the Gallbladder

• Cholelithiasis (Gallstones): Formed from cholesterol or bilirubin, often asymptomatic but may lead to pain and intolerance to fatty foods.
• Cholecystitis: Inflammation often caused by gallstones, leading to pain, fever, and leukocytosis.

Pancreatic Disorders

• Pancreatitis: Inflammation caused by obstruction of the pancreatic duct, leading to enzyme backup and damage.

Cancer of Accessory Organs

• Liver Cancer: Often metastatic; hepatocellular carcinoma is common and usually asymptomatic until late stages.
• Gallbladder Cancer: Rare, often diagnosed late due to asymptomatic early stages.
• Pancreatic Cancer: Linked with advanced malignancy, symptoms usually emerge after tumor progression.

This quiz covers key clinical manifestations associated with gastrointestinal dysfunction, including anorexia and vomiting. It is designed for students studying pathophysiology and aims to assess their understanding of these conditions. Prepare to delve into the complexities of digestive function as outlined in the summer 2024 curriculum.