Gastrointestinal disorder Flashcards
what is dyspepsia?
Defined as an episodic or persistent discomfort or pain in upper abdomen that may be accompanied of a sensation of fulness, bloating, heartburn, nausea, vomiting, belching, or burping.
what is functional dyspepsia?
Functional dyspepsia (Rome IV criteria):
Prescence of one or more of the following:
Bothersome postprandial fullness
Bothersome early satiation
Bothersome epigastric pain
Bothersome epigastric burning
what is most common cause of dyspepsia?
Functional dyspepsia (most common cause; results from interaction between increased visceral afferent sensitivity, delayed gastric emptying, and psychosocial stressors).
Food or drug intolerance (eating too much, too quickly, high-fat meals, eating during stress, drinking too much coffee, alcohol, etc.).
Peptic ulcer disease, GERD , H. pylori infection, cancer , pancreatic disease, biliary tract disease, pregnancy.
Other (gastroparesis, thyroid disease, chronic kidney disease, hernias, chronic intestinal ischemia).
what are the different types of causes of constipation with examples for each?
Mechanical: obstruction (malignancy; internal or external masses), strictures.
Anatomical: fissure, anismus, rectocele.
Metabolic: hypercalcemia inhibits sodium channels affecting neuronal excitation and reducing the tone and excitability of the bowel smooth muscle. Other hypomagnesemia.
Endocrine: hypothyroidism inhibits Cl−/HCO3− anion exchange and reduces intestinal motility. Deposition and accumulation of glycosaminoglycans (hyaluronic acid) that impairs motility. Clinically evident as reduced peristalsis, may produce distension, pain, etc. other diabetic autonomic neuropathy,
Neurological: multiple sclerosis leads to altered autonomic nerve response and reduced reflex responses after a meal. Other Parkinson disease.
what are the classes of constipation?
Rheumatological: scleroderma produces deposition and accumulation of collagen in GIT mucosal leading to fibrosis, reduced motility, atrophy pf smooth muscle and reduced ability to contract.
Pelvic floor dyssynergia: lack of relaxation of external anal sphincter and puborectalis muscle leads to an ineffective feces’ evacuation.
IBS-C: Reduced colonic motility due to impaired interaction between enteric and central nervous system (mechanism unknown; many pathways).
Drugs: opioids bind to receptors on gut wall and inhibit excitatory pathways within enteric nervous system. Anticholinergics inhibit action of parasympathetic nervous system.
what is nausea and what is vomiting?
Nausea: vague, intensely disagreeable sensation of sickness or “queasiness”.
Vomiting: expulsion of gastric contents following spasmodic respiratory and abdominal movements.
what is regurgitation and what is rumination?
Regurgitation: effortless reflux of liquid or food stomach contents.
Rumination: chewing and swallowing of food that is regurgitated volitionally after meals.
what are the complications of vomiting?
Complications:
Dehydration, hypokalemia, metabolic alkalosis.
Aspiration (aspiration pneumonia, lung abscess).
Rupture of the esophagus (Boerhaave’s syndrome).
Bleeding secondary to a mucosal tear at the gastroesophageal junction (Mallory-Weiss syndrome).
what composes the vomiting center?
Vomiting center (medulla) is composed of the area postrema, nucleus tractus solitarius, and the central pattern generator.
what is the pathophysiology of vomiting?
Receives stimuli from:
Visceral afferent fibers (serotonin receptors; vagus nerve sending signals of distension, irritation, infection).
Vestibular system (fibers have histamine H1 and muscarinic receptors M1).
Amygdala (may send signals in anticipation to events (chemotherapy).
Chemoreceptor trigger zone (in area postrema of medulla, outside blood brain barrier).
Stimulated by drugs, chemotherapeutic agents, toxins, hypoxia, uremia, acidosis, and radiation therapy.
what are the 2 types of dysphagia?
Oropharyngeal dysphagia:
Neurological: cerebrovascular accidents, brainstem infarctions with cranial nerve involvement, basal ganglia disorders (Parkinson disease), head and neck injuries/surgery, multiple sclerosis, brain tumor, botulism, amyotrophic lateral sclerosis, degenerative cervical spine disease.
Muscular: polymyositis, muscular dystrophy, and myasthenia gravis.
Anatomical: Zenker diverticulum, enlarged thyroid, esophageal web, tumors, abscess, external compression by aortic aneurysm.
Esophageal dysphagia:
Mechanical obstruction: Schatzki ring, esophageal stricture or carcinoma, eosinophilic esophagitis.
Motility disorders: esophageal spasm, achalasia and scleroderma.
Rheumatologic: Sjogren syndrome, systemic lupus erythematosus, systemic sclerosis (CREST syndrome), rheumatoid arthritis.
Drugs: due to xerostomia, changes in esophageal motility, pill esophagitis or GERD.
what are the causes of oropharyngeal dysphagia?
Neurological: cerebrovascular accidents, brainstem infarctions with cranial nerve involvement, basal ganglia disorders (Parkinson disease), head and neck injuries/surgery, multiple sclerosis, brain tumor, botulism, amyotrophic lateral sclerosis, degenerative cervical spine disease.
Muscular: polymyositis, muscular dystrophy, and myasthenia gravis.
Anatomical: Zenker diverticulum, enlarged thyroid, esophageal web, tumors, abscess, external compression by aortic aneurysm.
what are the causes of esophageal dysphagia?
Mechanical obstruction: Schatzki ring, esophageal stricture or carcinoma, eosinophilic esophagitis.
Motility disorders: esophageal spasm, achalasia and scleroderma.
Rheumatologic: Sjogren syndrome, systemic lupus erythematosus, systemic sclerosis (CREST syndrome), rheumatoid arthritis.
Drugs: due to xerostomia, changes in esophageal motility, pill esophagitis or GERD.
what is achalasia?
Rare functional disorder resulting from progressive degeneration of ganglion cells in the myenteric plexus in the esophageal wall, leading to failure of relaxation of the lower esophageal sphincter (LES), accompanied by a loss of peristalsis in the distal esophagus.
Primary or idiopathic achalasia (unknown etiology).
Secondary achalasia: due to diseases that cause esophageal motor or abnormalities similar or identical to those of primary achalasia (Chagas disease, viral infections, malignant infiltration, etc.
Most frequent presentation: dysphagia for solids and liquids and regurgitation of bland undigested food or saliva. May have chest pain, heartburn (unresponsive to proton pump inhibitors), and difficulty belching.
what are the 2 forms of achalasia and their definitions?
Primary or idiopathic achalasia (unknown etiology).
Secondary achalasia: due to diseases that cause esophageal motor or abnormalities similar or identical to those of primary achalasia (Chagas disease, viral infections, malignant infiltration, etc.
Most frequent presentation: dysphagia for solids and liquids and regurgitation of bland undigested food or saliva. May have chest pain, heartburn (unresponsive to proton pump inhibitors), and difficulty belching.
what is the most frequent presentation of achalasia?
Most frequent presentation: dysphagia for solids and liquids and regurgitation of bland undigested food or saliva. May have chest pain, heartburn (unresponsive to proton pump inhibitors), and difficulty belching.
