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147 Cards in this Set
- Front
- Back
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Midgut development: 6th week, 10th week |
6th week: midgut herniates through umbilical ring 10th week: returns to abdominal cavity, rotates around SMA
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Midgut development: pathology |
malrotation of midgut, omphalocele, intestinal atresia, volvulus |
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Gastroschisis |
Extrusion of abdominal contents through abdominal folds, not covered by peritoneum |
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Omphalocele |
Persistence of herniation of abdominal contents into umbilical cord, sealed by peritoneum |
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Congenital pyloric stenosis |
Hypertrophy of the pylorus causes obstruction. Palpable "olive" mass in epigastric region and nonbilous projectile vomiting at 2-6 weeks old. Hypokalemic, hypochloremic metabolic alkalosis. Rx: surgical incision |
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Pancreatic embryology annular pancreas pancreas divisum |
annular pancreas: ventral pancreatic bud abnormally encircles second part of duodenum; forms ring of pancreatic tissue that may cause duodenal narrowing.
pancreas divisum: ventral and dorsal parts fail to fuse at 8 weeks. |
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Retroperitoneal structures: SAD PUCKER |
Suprarenal (adrenal) glands Aorta and IVC Duodenum (2nd through 4th parts) Pancreas (except tail) Ureters Colon (descending and ascending) Kidneys Esopaghus Rectum |
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Portal triad |
within hepatoduodenal ligament Proper hepatic artery common bile duct portal vein |
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Digestive wall anatomy-- Layers of Gut wall (MSMS) |
Mucosa: epithelium, lamina propria, muscularis mucosa Submucosa: includes submucosal nerve plexus (Meissner), Secretes fluid Muscularis externa: includes Myenteric nerve plexus (Auerbach), Motility Serosa: |
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SMA syndrome |
Transverse portion (third part) of the duodenum is entrapped between SMA and aorta, causing intestinal obstruction. |
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Foregut: artery, PS innervation, vertebral level |
Artery: Celiac PS innervation: vagus Vertebral level: T12/L1 |
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Midgut: artery, PS innervation, vertebral level |
Artery: SMA PS innervation: Vagus Vertebral level: L1 |
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Hindgut: artery, PS innervation, vertebral level |
Artery: IMA PS innervation: pelvic vertebral level: L3 |
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Celiac trunk branches |
common hepatic Splenic Left gastric
constitute major blood supply to stomach |
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Portosystemic anastomases: Esophagus |
left gastric-->esophageal esophageal varices |
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Portosystemic anastomses: Umbilicus |
paraumbilical-->small epigastric veins of anterior abdominal wall clinical sign: Caput medusae |
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Portosystemic anastomoses: Rectum |
Superior rectal-->middle and inferior rectal Anorectal varices |
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TIPS (transjugular intrahepati portosystemic shunt) |
shunt between portal vein and hepatic vein relieves portal HTN by shunting blood to systemic circulation, bypasisng the liver |
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Pancreas head tumors |
can cause obstruction of common bile duct alone painless jaundice |
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Femoral region organization |
NAVEL: lateral to medial Nerve Artery Vein Empty space Lymphatics |
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Diaphragmatic hernia |
Herniation of abdominal structures through the thorax most common on left side due to right side protection by liver hiatal hernia most common: stomach herniates upward through the esophageal hiatus of the diaphragm
Sliding hiatal hernia: "hourglass stomach" Paraesophageal hernia: Fundus protrudes into the thorax |
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Indirect inguinal hernia |
Goes through the internal (deep) inguinal ring, external inguinal ring, and into the scrotum. Enters internal inguinal ring lateral to inferior epigastric artery. Occurs in infants owing to failure of processus vaginalis to close (can form hydrocele). Much more common in males.
Follows path of descent of testes Covered by all three layers of spermatic fascia |
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Direct inguinal hernia |
Protrudes through the inguinal (Hasselbach) triangle. Bulges directly through abdominal wall medial to Inferior epigatric artery. Goes through the external (superficial) inghinal ring only. Covered by external spermatic fascia. usually in older men.
medial to inferior epigastric artery: direct hernia |
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Femoral hernia |
Protrudes below inguinal ligament through femoral canal below and lateral to pubic tubercle More common in females. leading cause of bowel incarceratoin.
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Gastrin (Source, action, regulation, notes) |
Source: G cells (antrum of stomach, duodenum) Action: increase gastric H+ secretion, increase growth of gastic mucosa, increase gastric mucosa Regulation: increase by stomach distension/alkalinization, decreased by ph<1.5 Notes: increased in chronic atrophic gastritis, increased in ZE syndrome, increased by chronic PPI use |
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Somatostatin (Source, action, regulation, notes) |
Source: D cells (pancreatic islets, GI mucosa) Action: decreased gastric acid and pepsinogen secretion, decreased pancreatic and small intestine fluid secretion, decreased gallbladder contraction, decreased insulin and glucagon release Regulation: decreased by vagal stimulation, increased by acid Notes: inhibits secretion of GH, insulin, and other hormones (encourages somatostasis). octreotide is an anlog used to treat acromegaly, insulinoma, carcinoid syndrome, variceal bleeding. |
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Cholecystokinin (Source, action, regulation, notes) |
Source: I cells (duodenum, jejunum) Action: increase pancreatic secretion, increase gallbladder contraction, decrease gastric emptying, increase sphincter of Oddi relaxation Regulation: increase by FFA, amino acids Notes: CCK acts on neural muscarinic pathways to cause pancreatic secretion |
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Secretin (Source, action, regulation, notes) |
Source: S cells (duodenum) Action: increase pancreatic HCO3- secretion, decrease gastric acid secretion, increase bile secretion Regulation: increased by acid, FA in lumen of duodenum Notes: HCO3- neutralizes gastric acid in duodenum, allowing pancreatic enzymes to function |
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GIP (Source, action, regulation, notes) |
Source: K cells (duodenum, jejunum) Action: exocrine-- decrease gastric H+ secretion; Endocrine-- increase insulin release Regulation: increased by FA, AA, oral glucose
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Motilin (Source, action, regulation, notes) |
Source: small intestine Action: produces migrating motor complexes Regulation: increased in fasting state |
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VIP (Source, action, regulation, notes) |
Source: parasympathetic ganglia Action: increase intestinal water and electrolyte secretion, increase relaxation of intestinal smooth muscle and sphincters regulation: increase by distention and vagal stimluation, decrease by adrenergic input Notes: VIPoma: non alpha, non beta islet cell pancreatic tumor that secretes VIP |
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Nitric oxide (Source, action, regulation, notes) |
Action: increases SM relaxation, lncluding LES |
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Intrinsic Factor (Source, action, regulation, notes) |
Source: parietal cells (stomach) Action: Vitamin B12-binding protein (required for B12 uptake in terminal ileum) Notes: AI destruction of parietal cells--> chronic gastritis and pernicious anemia |
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Gastric Acid(Source, action, regulation, notes) |
Source: parietal cells (stomach) action: decrease stomach pH Regulation: increase by histamine, Ach, gastrin decrease by somatostatin, GIP, prostaglandin, secretin Notes: Gastrinoma: gastrin-secreting tumor that causes high levels of acid and ulcers refractory to medical rx (ie, PPI0 |
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Pepsin (Source, action, regulation, notes) |
Source: chief cells (stomach) action: protein digestion regulation: increased by vagal stimulation, local acid Notes: pepsinogen (inactive) is converted to pepsin (active) in presence of H+ |
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HCO3- (Source, action, regulation, notes) |
Source: mucosal cells (stomach, duodenum, salivary glands, pancreas), Brunner glands (duodenum) Action: neutralizes action regulation: increased by pancreatic and biliary secretion with secretin Notes: HCO3- is trapped in mucus that covers gastric epithelium |
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Pancreatic enzymes (alpha amylase, lipase, protease, trypsinogen) |
alpha amylase: starch digestion, secreted in active form Lipases: fat digestion (trypsin, chymotrypsin elastase, carboxypeptidase); secreted as proenzymes known as zymogens trypsinogen: converted to active enzyme trypsin by enterokinase/enteropeptidase, a brush-border enzyme on duodenal and jejunal mucosa |
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Vitamin/mineral absorption Iron Folate B12 (Iron Fist Bro) |
Iron: Absorbed as Fe2+ in duodenum Folate: Absorbed in small bowel B12: Absorbed in terminal ileum along with bile salts, requires IF |
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Peyer patches |
Unencapsulated lymphoid tissue found in lamina propria and submucosa of ileum. Contains specialized M cells that sample and present antigens to immune cells. |
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Bilirubin direct/indirect |
Direct bilirubin: Conjugated with glucoronic acid; water soluble indirect bilirubin: unconjugated, water-insoluble |
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Achalasia |
Failure of relaxation of LEs due to loss of myenteric (Auerbach) plexus. High LES resting pressure and uncoordinated peristalsis.--> progressive dysphagia Barium swallow shows dilated esophagus with an area of distal stenosis. increased risk of SCC
Secondary achalasia may arise from Chaga's disease or malignancies |
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Boerhaave syndrome |
Esophageal pathology Transmural with pneumomediastinum d/t violent retching; surgical emergency |
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Eosinophilic esophagitis |
Esophageal pathology Infiltration of eosinophils in the esophagus in atopic patients. Food allergens--> dysphagia, heartburn, strictues. Unresponsive to GERD rx |
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Esophageal strictures |
Esophageal pathology Associated with lye ingestion and acid reflux |
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Esophageal varices |
Esophageal pathology Dilated submucosal veins in lower 1/3 of esophagus secondary to portal HTN. Common in alcoholics, may be source of upper GI bleeding |
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Esophagitis |
Esophageal pathology Associated with reflux, infection in immunocompromised (Candida, HSV-1, CMV), or chemical ingestion |
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GERD |
Esophageal pathology Presents as heartburn, regurgitation upon lying down Nocturnal cough/dyspnea, adult-onset asthma, decrese in LES tone
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Mallory-Weiss syndrome |
Esophageal pathology Mucosal lacerations at the GE junciton due to severe vomiting. Leads to hematemesis. usually found in alcoholics and bulimics. |
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Plummer-Vinson syndrome |
Triad of dysphagia, iron deficiency anemia, Esophageal webs "Plumbers DIE" |
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Sclerodermal esophageal dysmotility |
Esophageal smooth muscle atrophy--> decreased LES pressure and dysmotility-->acid reflux and dysphagia-->stricture, Barrett esophagus, and aspiration. Part of CREST syndrome |
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Barrett esophagus |
glandular metaplasia-- replacement of nonkeratinized stratified squamos epithelium with intestinal epithelium (nonciliated columnar with goblet cells) in distal esophagus. Due to chronic acid reflux (GERD). Associated with esophagitis, esophageal ulcers, and increased risk of esophageal adenocarcinomas. |
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Esophageal cancer |
Can be squamos cell carcinoma or adenocarcinoma Typically presents with progressive dysphagia (solids, then liquids), and weight loss; poor prognosis. worldwide: SCC most common Americal: AdenoCa most common squamos cell: upper 2/3 Adenocarcinoma: lower 1/3 |
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Acute gastritis |
Disruption of mucosal barrier inflammation
Caused by: NSAIDs-->decreased PGE2-->decreased gastric mucosa protection Burns (Curling ulcer) Brain injury (Cushing ulcer)
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Chronic gastritis: Type A |
type A: fundus/body Autoimmune disorder characterized by Autoantibodies to parietal cells, pernicious anemia, and achlorhydria. Associated with other AI disorders
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Chronic gastritis: type B |
Type B: antrum Most common type Caused by H. pylori infection increased risk of MALT lymphoma
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Menetrier disease |
Gastric hyperplasia of mucosa--> hypertrophied rugae, excess mucus production with resultant protein loss and parietal cell atrophy with decreased acid production. Precancerous. Rugae of stomach are so hypertrophied that they look like brain gyri. |
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Stomach cancer |
Commonly gastric adenoCA; lymphoma; rarely carcinoid. Early aggressive local spread with node/liver mets. Often presents with weight loss, early satiety, and in some cases acanthosis nigricans.
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Intestinal stomach cancer |
Associated with H. pyori, dietary nitrosamines, tobacco smoking, achlorhydria, chronic gastritis. Commonly on lesser curvature of antrum; looks like ulcer with raised margins
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Diffuse stomach cancer |
Not associated with H. pylori; signet ring cells (mucin-filled cells with peripheral nuclei); stomach wall grossly thickened and leathery (linitis plastica) |
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Virchow node Krukenberg tumor Sister mary Joseph Nodule |
Virchow Node: Involvement of left supraclavicular node by mets from stomach
Krukenberg tumor: bilateral mets to ovaries. Abundant mucin-secreting, signet ring cells.
Sister Mary Joseph nodule: Subcutaneous periumbilical mets. |
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PUD Gastric Ulcer duodenal Ulcer |
Gastric ulcer: pain greater with meals, H. pylori infection in 705, decreased mucosal protection, NSAIDs can cause, increased risk of carcinoma; biopsy margins to r/o malignancy
Duodenal ulcer: pain decreases with meals, almost 100% due to H. pylori infeciton, decreased mucosal protection or increased gastric acid secretion, ZE syndrome, benign, hypertrophy of Brunner glands. |
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Ulcer complications |
Hemorrhage Perforation |
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Malabsorption syndromes |
Can cause diarrhea, steatorrhea, weight loss, weakness, vitamin and mineral deficiencies
Celiac disease Disaccharidase deficiency Pancreatic insufficiency Tropical sprue Whipple disease |
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Celiac disease |
AI-mediated intolerance of gliadin (gluten protein found in wheat) malabsorption and steatorrhea. Associated with HLA-DQ2, HLA-DQ8, northern Europhean descent, dermatitis herpetiformis, decreased bone density. findings: anti-endomysial, anti tissue transglutaminase, and anti-gliadin antibodies. Blunting of villi; lymphocytes in lamina propria. Moderately increased risk of malignancy (eg, T cell lymphoma)
Decreased mucosal absorption and primarily affects distal duodenum and/or proximal jejunum. rx: gluten-free diet |
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Disaccharidase deficiency |
Most common is lactase deficiency-->milk intolerance-->osmotic diarrhea
lactose tolerance test |
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Pancreatic insufficiency |
Due to CF, obstructing cancer, chronic pancreatitis. Causes malabsorption of fat-soluble vitamins (ADEK), vit B12 |
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Tropical sprue |
Similar findings as celiac sprue (affects small bowel), but responds to antibiotics. Unknown cause, but seen in residents or recent visitors to tropics. |
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Whipple disease |
Infection with T. whipple (gram positive) PAS+ foamy macrophgaes in intestinal lamina propria mesenteric nodes Cardiac symptoms Arthralgias Neurologic sx are common Most often occrs in older men
"Foamy whipped cream in a CAN) |
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Crohn disease (Location, Gross morphology, microscopic morphology, complications, intestinal manifestations, extraintestinal manifestations, rx) |
Location: any portion of GI tract, usually in terminal ileum and colon. Skip lesions, rectal sparing Gross morphology: Transmural inflammation--> fistulas. Cobblestone mucosa, creeping fat, bowel wall thickening ("string sign" on barium swallow x-ray), linear ulcers, fissures Mircoscopic morphology: Noncaseating granulomas and lymphoid aggregated (Th1-mediated) Complications: Strictures, fistulas, perianal disease, malabsorption, nutritional depletion, colorectal cancer, gallstones Intestinal manifestation: Diarrhea that may or may not be bloody Extraintestinal manifestation: Migratory polyarthritis, erythema nodosum, ankylosing spondylitis, pyoderma gangrenosum, aphthous ulcers,uveitis, kidney stones Treatment: Corticosteroids, azathioprine, antibiotics (ciprofloxacin, metronidazole) For Chron disease, think of a fat granny and an old crone skipping down a cobblestone road away from the wreck (rectal sparing)
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Ulcerative colitis |
Location: Colitis=colon inflammation. Continuous colonic lesions, always with rectal involvement. Gross morphology: Mucosal and submucosal inflammation only. Friable mucosal pseudopolyps with freely hanging mesentary. Loss of haustra--> "lead pipe" appearance on imaging. Microscopic morphology: Crypt abscesses and ulcers, bleeding, no granulomas (Th2 mediated) Complications: Malnutrition, sclerosing cholangitis, toxic megacolon, colorectal carcinoma (worse with right-sided colitis or pancolitis) Intestinal manifestation: Bloody diarrhea Extraintestinal manifestations: Pyoderma gangrenosum, erythema nodosum, primary sclerosing cholangitis, ankylosing spondylitis, aphthous ulcers, uveitis. Rx: 5-aminosalicylic preparations (mesalamine), 6-mercaptopurine, infliximab, colectomy.
ULCCCERS Ulcers Large intestine Continuous, Colorectal carcinoma, Crypt abscesses Extends proximally Red diarrhea Sclerosing cholangitis |
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Irritable bowel syndrome |
Recurrent abdominal pain associated with two or more of the following: Pain improves with defecation Change in stool frequency Change in appearance of stool
No structural abnormalities. Most common with middle-aged women. Chronic symptoms. May present with diarrhea, constipation, or alternating sx. Pathophys is multifaceted. Rx syptoms. |
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Appendicitis |
Acute inflammation of the appendix due to obstruction by fecalith in adults or lymphoid hyperplasia in children. Initial diffuse periumbilical pain migrates to McBurney's point. Nausea, fever, may perforate-->peritonitis; may elicit psoas, obturator, Rovsing sign, guarding and rebound tenderness on exam. DDx: diverticulitis (elderly), ectopic pregnancy (use hCG to r/o) rx: appendctomy |
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Diverticula of the GI tract |
diverticulum diverticulosis diverticulitis |
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Diverticulum |
Blind pouch protruding form the alimentary tract that communicates with the lumen of the gut. Most diverticula (esophagus, stomach, duodenum, colon) are acquired and are termed "false" in that they lack or have an attenuated muscularis externa. Most often in sigmoid colon. "True" diverticulum: All 3 gut wall layers outpouch (eg, Meckel) "False" diverticulum: only mucosa nd submucosa outpouch. Occur especially where vasa recta perforate muscularis externa. |
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Diverticulosis |
Many false diverticula of the colon, commonly sigmoid. Common (>50% of people >60 y/o) Caused by increased intraluminal pressure and focal weakness in colonic wall. Associated with low-fiber diets.
Often asx or associated with vague discomfort. A common cause of hematochezia. Complications include diverticulitis, fistulas. |
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Diverticulitis |
Inflammation of diverticula. classically causes LLQ pain, fever, leukocytosis. May perforate-->peritonitis, abscess formation, or bowel stenosis. Give abx May also cause colovesical fistula (fistula with bladder)-->pneumaturia. Sometimes called "left-sided appendicitis" due to overlapping clinical presentation. |
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Zenker diverticulum |
Pharyngoesophageal false diverticulum. Herniation of mucosal tissue at Killian triangle. dysphagia, obstruciton, halitosis elderly males |
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Meckel diverticulum |
True diverticulum. Persistence of vitelline duct. dx: pertechnetate study for uptake by ectopic gastic mucosa
The five 2's:
2 inches long 2 feet from ileocelcal valve 2% of populaiton commonly presents in first 2 years of life. May have 2 types of epithelia (gastric/pancreatic)
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Malrotation |
anomaly of midgut rotation during fetal development--> improper positioning of bowel, formation of fibrous bands (Ladd bands). Can lead to volvulus, duodenal obstruction. |
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Volvulus |
Twisting of portion of bowel around its mesentary; can lead to obstruction and infarction. Can occur throughout the GI tract. Midgut volvulus more common in infants and children. Sigmoid volvulus more common in elderly. |
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Intussusception |
telescoping of proximal bowel segment into distal segment, commonly at iliocecal junction. Compromised blood supply--> intermittent abdominal pain with "currant jelly" stools. unusual in adults. Usually in kids, idiopathic, can be associated with recent enteric or respiratory viral infection. Abdominal emergency in early childhood, with bull's eye appearance on ultrasound. |
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Hirschprung diease |
Congenital megaolon characterized by lack of ganglion cells/enteric nervous plexuses (Auerach and Missner plexuses) in segment of colon. Due to failure of neural crest cell migration. Associated with mutations in RET gene. Presents with bilious emesis, abdominal distention, failure to pass meconium--> chronic constipation. Normal portion of colon proximal to aganglionic segment is dilated resulting in "transition zone". involves rectum Think of Hirschprung as a giant spring that has sprung in the colon. Risk increased with down syndrome. dx: rectal suction biopsy. rx: resection. |
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Acute mesenteric ischemia |
often due to occlusion of SMA small bowel necrosis abdominal pain out of proportion to physical findings red "currant jelly" stools |
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Adhesion |
fibrous band of scar tissue; after surgery |
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angiodysplasia |
tortuous dilatation of vessels-->hematochezia most often in cecum, terminal ileum, ascending colon More common in older patients. Confirmed by angiography |
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Duodenal atresia |
Early bilous vomiting proximal stomach distension ("double bubble") on X ray failure of small bowel recanalization Associated with Down Syndrome |
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ileus |
intestinal hypomotility without obstruction-->constipation and decreased flatus; distended/tympanic abdomen with decreased bowel sounds. Assocaited with abdominal surgeries, opiates, hypokalemia, sepsis. rx: bowel rest, electrolyte correction, cholinergic drugs (stimulate intestinal motility) |
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Ischemic colitis |
Reduction in itestinal blood flow causes ischemia. Pain after eating-->weight loss. Commonoccurs at watershed areas (splenic flexure, distal colon). Typicall affects elderly. |
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meconium ileus |
In CF, meconium plug obstructs intestine, preventing stool passage at birth |
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necrotizing enterocolitis |
Premature, formula-fed infants, immature immune system necrosis of intestinal mucosa possible perforation free air in abdomen, portal venous gas |
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Colonic polyps |
small growths of tissue within colon. neoplastic or non-neoplastic. classified as flat, sessile, or pedunculated |
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Hyperplastic polyps |
Non-neoplastic Small, located in rectosigmoid area |
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Hamartomatous |
Non-neoplastic. Solitary lesions don't have risk of malignant transformation. Associated with Peutz-Jeghers syndrome and juvenile polyposis. |
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Adenomatous |
Neoplastc chromosomal instability (APC, KRAS) Tubular histology has less malignant potential than villous. Tubulovillous-- intermediate malignant potential |
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Serrated |
Premalignant, via CpG hypermethylation phenotype pathway with microsatellite instability and mutations in BRAF. "Saw-tooth" pattern of crypts on biopsy. Up to 20% of cases of sporadic CRC. |
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Familial adenomatous polyposis |
AD mutation of APC tumor suppressor gene on chromosome 5q. 2-hit hypothesis. 100% progress to CRC unless colon is resected. Thousands of polyps arise starting after puberty; pancolonic always involves rectum |
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Gardner syndrome |
FAP+ osseous and soft tissue tumors congenital hypertrophy of retinal pigment epithelium impacted/supernumerary teeth |
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Turcot syndrome |
FAP+ malignant CNS tumor Turcot=Turban |
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Peutz-Jeghers syndrome |
AD syndrome featuring numerous hamartomas throughout GI tract, alng with hyperpigmented mouth, lips, hands, genitlaia. Associated with increased risk of colorectal,b reast, stomach, small bowel, pancreatic cancer
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Juvenile polyposis syndrome |
AD syndrome in children (typically <5 y/o) numerous hamartomatous polyps in stomach, colon, small bowel increased risk of CRC |
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Lynch syndrome |
HNPCC AD mutation of DNA mismatch repair genes with subsequent microsatellite instability 80% progress to CRC proximal colon always involved Endometrial, ovarian, skin cancers Can be ID'd clinically in families using 3-2-1 rule 3 relatives with Lynch syndrome-associated cancers across 2 generations, 1 of whom must be diagnosed under 50 y/o |
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Colorectal cancer |
most patients <50 y/o, 25% have family hx risk factors: polyps, tobacco, diet of processed meat with low fiber presentation: rectosigmoid>ascending>descending dx: iron def. anemia in males, postmenopausal females raises suspicion. Screen patients >50 y/o with colonoscopy, sigmoidoscopy, occult stool sample "apple-core" lesion on barium enema x-ray CEA tumor marker; good for monitoring recurrence |
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Molecular pathogenesis of CRC |
2 molecular pathways: 1. microsatellite instability pathway (15%): DNA mismatch repair gene mutations 2. APC/beta catenin chromosome instability pathway
order of gene events: AK-53
(loss of APC gene, KRAS mutation, p53 loss (tumor suppressor)) |
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cirrhosis and portal HTN |
cirrhosis: diffuse bridging fibrosis and nodular regeneration via stellate cells disrupts normal architecture of liver. increased risk for HCC Etiologies: EtOH, chronic viral hepatitis, biliary disease, genetic/metabolic disorders portosystemic shunts partially alleviate portal HTN esophageal varices caput medusae anorectal varices |
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ALP (alkaline phosphatase) |
Cholestatic and obstructive hepatobiliary disease, HCC, infiltrative disorders, bone disease |
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Aminotransferases (AST, ALT) |
viral hepatitis (ALT>AST) EtOH hepattis (AST>ALT) |
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Amylase |
Acute pancreatitis, mumps |
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Ceruloplasmin |
decreased in Wilson disease |
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GGT
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increased in liver and biliary diseases, but not in bone disease associated with EtOH use |
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Lipase |
Acute pancreatitis (most specific) |
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Reye syndrome |
Rare, often fatal childhood hepatic encephalopathy mitochondrial abnormalities, fatty liver, hypoglycemia, hepatomegaly, coma Viral infection (esp VZV, hep B) that has been treated with aspirin Aspirin metabolites decrease beta oxidation by reversible inhibition of mitochondrial enzymes Avoid aspirin in children, except in those with Kawasaki disease |
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Hepatic statosis |
Macrovascular fatty change that may be reversible with EtOH cessation |
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alcoholic hepatitis |
Requires sustained, long-term consumption swollen, necrotic hepatocytes, PMN infiltration Mallory bodies (intracytoplasmic inclusions of damaged keratin fibers) Make a toAST with EtOH: AST>ALT (ratio>1.5)
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Alcoholic cirrhosis |
final and irreversible form micronodular, irregularly shrunken liver with "hobnail" appearnce. Sclerosis around central vein manifestations of chronic liver disease |
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NAFLD |
metabolic syndrome (insulin resistance)--> fatty infiltration of hepatocytes--> cellular "ballooning" and eventual necrosis.
May cause cirrhosis and HCC. independent of EtOH use
ALT>AST (L for lipids) |
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hepatic encephalopathy |
Cirrhosis-->portosystemic shunts-->decreased NH3 metabolism-->neuropsych dysfunction.
disorientation, asterixis, coma
increased NH3 production/absorption, decrased NH3 removal
rx: lactulose (increase NH4+ generation), rifaximin |
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HCC |
most common primary malignant tumor of liver in adults associated with HBV, cirrhosis associated with specific carcinogens (aflatoxin from Aspergillus) may lead to Budd-Chiari syndrome jaundice, tender hepatomegaly, asictes, polycytehmia, anorexia Spreads hematogenously dx: increased alpha fetoprotein, ultrasound/contrast CT/MRI biopsy |
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other liver tumors (4) |
cavernous hemangioma: common, benign hepatic adenoma: rare, benign, oral contraceptives, anabolic steroids angiosarcoma: malignant tumor of endothelial origin; arsenic/vinyl chloride exposure Mets: GI, breast, lung cancer. Most common overall |
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Budd-Chiari syndrome |
Thrombosis or compression of hepatic veins with centrilobular congestion and necrosis. Congestive liver isease, no JVD Associated with hypercoagulable states, polycythemia vera, postpartum state, HCC May cause nutmeg liver (mottled appearance) |
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alpha 1 antitrypisin deficiency |
misfolded gene product protein aggregates in hepatocellular ER--> cirrhosis with PAS+ globules in liver codominant trait
in lungs: decreased alpha1 antitrypsin->too much elastase-->panacinar emphysema |
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jaundice |
abnormal yellowing of skin and/or sclera due to bilirubin deposition Occurs at high bilirubin levels in blood secondary to increased production or defective metabolism |
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Unconjugated (indirect) bilirubin |
hemolytic, physiologic (newborns), Crigler-Najjar, Gilbert syndrome |
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Conjugated (direct) hyperbilirubinemia |
biliary tract obstruction: gallstones, cholangiocarcinoma, pancreatic or liver cancer, liver fluke. biliary tract disease: primary sclerosing cholangitis, primary biliary cirrhosis excretion defect: Dubin-Johnson syndrome, Rotor syndrome |
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Mixed (direct and indirect) hyperbilirubinemia |
Hepatitis, cirrhosis |
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Physiologic neonatal jaundice |
At birth, immature UDP-glucoronosyltransferase--> unconjugated hyperbilirubinemia-->jaundice/kernicterus rx: phototherapy (converts unconjugated bilirubin to water-soluble form) |
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hereditary hyperbilirubinemias (3) |
gilbert syndrome Crigler-Najjar, type I Dubin-Johnson syndrome |
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Gilbert syndrome |
Mildly decreased UDP-glucuronosyltransferae conjugation and impaired bilirubin uptake Asymptomatic or mild jaundice increased unconjugated bilirubin without overt hemolysis bilirubin increases with fasting and stress
very common; no clinical consequence |
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Crigler-Najjar syndrome, type I |
Absent UDP-glucoronosyltransferase presents early in life; patients die within a few years jaundice, kernicterus, increased unconjugated bili rx: plasmapheresis, photorx type II is less severe, responds to phenobarbitol, which icnreases liver enzyme synthesis |
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Dubin-Johnson syndrome |
conjugated hyperbilirubinemia due to defective liver excretion Grossly black liver benign
Rotor syndrome is similar but even milder and does not cause black liver |
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Wilson disease (hepatolenticular degeneration) |
Inadequte hepatic copper excretion and failure of copper to enter circulation as ceruloplasmin. Leads to copper accumulation (liver, brain, cornea, kidneys--Fanconi syndrome, joints) AR inheritance-- chromosome 13 Copper is normall excreted into bile by hepatocyte copper transporting ATPase (ATP7B gene) rx: chelation with penicillamine or trientine, oral zinc
decreased cruloplasmin, cirrhosis, corneal deposits (Kayser-Fleischer rings), copper accumulation, HCC Hemolytic anemia Basal ganglia degeneration (parkinsonism) Asterixis Dementia, dyskinesia, Dysarthria
"Copper is Hella BAD" |
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hemochromatosis |
hemosiderosis is the deposition of hemosiderin (iron), which stains blue. Hemochromatosis is the disease cuased by Fe deposition. classic triad of micronodular cirrhosis, diabetes mellitus, skin pigmentation bronze diabetes HF, testicular atrophy, increased risk of HCC primary or secondary to chronic transfusion rx increased ferritin, increased Fe, decreased TIBC, increased transferrin sturaiton id on biopsy with Prussian blue stain primary disease d/t C282Y or H63D mutation in HFE gene. Associated with HLA-A3 Fe loss through menstruation, slows progression in women Rx: repeated phlebotomy, chelation with deferasirox, deferoxamine, deferipone |
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Biliary tract disease |
pruritis, jaundice, dark urine, light-colored stool, hepatosplenomegaly.
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Cholestatic LFTs |
increased conjugated bili increased cholesterol increased ALP |
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secondary biliary cirrhosis |
pathology: extrahepatic biliary obstruction epidemiology: patients with known obstructive lesions (gallsotnes, biliary strictures, pancreatic carcinoma) may be complicated by ascending cholangitis |
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primary biliary cirrhosis |
AI rxn lymphocytic infiltrate granulomas Epidemiology: middle-aged women Anti-mitochondrial Ab CREST, Sjogren syndrome, rheumatoid arthritis |
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primary sclerosing cholangitis |
"onion skin" bile duct fibrosis alternating strictures/dilatation ("beading") on ERCP
epi: young men with IBD
hypergammaglobulinemia (IgM) MPO-ANCA/pANCA positive associated with UC can lead to secondary biliary cirrhosis |
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Gallstones risk factors (4 Fs) |
Female Fat Fertile Forty |
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Cholesterol stones |
radiolucent 80% of stones
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Pigment stones |
black=radiopaque; brown=radiolucent
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Charcot triad of cholangitis |
Jaundice Fever RUQ pain |
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Cholecystitis |
Acute or chronic inflammation of gallbladder usually from gallstone dx with ultrasound or cholescintigraphy |
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Murphy sign |
inspiratory arrest on RUQ palpation due to pain present in cholecysitis |
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Porcelain gallbladder |
Calcified gallbladder due to chronic cholecystitis rx: prophylactic cholecystectomy due to high rates of gallbladder cancinoma |
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acute pancreatitis |
Autodigestion of pancreas by pancreatic enzymes Causes: GET SMASHED Gallstones, EtOH, Trauma, Steroids, Mumps, AI disease, Scorpion sting, HyperCa2+, Hypertriglyceridemia, ERCP, drugs Labs: increased amylase, lipase clinical presentation: epigastric abdominal pain radiating to back, anorexia, nausea |
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Chronic pancreatitis |
Chronic inflammation, atrophy, calcification of pancreas EtOH use, idiopathic CFTR mutations (CF) can lead to pancreatic insufficiency steatorrhea, fat soluble vitamin deficiency, DM amylase and lipase may or may not be elevated (always elevated in acute pancreatitis) |
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Pancreatic AdenoCA |
Average survival: 1 year after dx aggressive tumor arising from pancreatic ducts already mets at time of presentation tumors most common at pancreatic head (obstructive jaundice) associated wiht CA-19-9 tumor marker Risk factors: tobaccou, chronic pancreatitis, diabetes, >50 y/o, Jewish, AA males
Presents with: abdominal pain radiating to back, weight loss, migratory throbophlebitis-- redness and tenderness on palpation of extremities (Trouseeau syndrome) obstrucitve jaundice
Rx: Whipple procedure, chemorx, radiation rx |
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