Chapter 13: The GI Tract Flashcards
Disordered esophageal motility (uncoordinated peristalsis) with inability to relax the lower esophageal sphincter (LES)
S/S: Dysphagia for solids & liquids, putrid breath, High LES pressure on esophageal manometry, “bird-beak” sign on barium swallow study
Results in hypertrophy/dilation of esophagus
What is damaged?
How can the damage occur?
What is there an increased risk of?
Achalasia
1) Loss or damaged ganglion cells in the myenteric plexus
2) idiopathic or secondary to known insult (viral, autoimmune, genetic) In Latin America, complication of Chagas Disease
3) Esophageal Squamous cell carcinoma
Thin protrusion of esophageal mucosa membranes, most often into the lumen of upper esophagus
Presents with dysphagia for poorly chewed food, esophageal substernal pain, and aspiration or regurgitation of foods and liquids
Increased risk for esophageal sqamous cell carcinoma
Esophageal Web
Rings are thicker and contain smooth muscle
Cervical esophageal web (cause dysphagia)
Mucosal lesions of the mouth and pharynx
Iron-deficiency anemia
What is a potential complication?
Plummer-Vinson Syndrome
Carcinoma of oropharynx and upper esophagus
Remember: Plummers DIG (dysphagia, iron def, glossitis)
Autoimmune disease characterized by activation of fibroblasts and deposition of collagen (fibrosis)
Esophageal smooth muscle atrophy, decreased LES pressure, dysmotility, then acid reflux and dysphagia, then stricture > Barrett esophagus, and aspiration
Which antibodies would you look for?
What is CREST Syndrome (throwback thursday)?
Why do we care about this in the GI Unit?
Scleroderma
Anti-Scl70 and anti-Centromere antibodies (for CREST)
CREST (systemic sclerosis, limited type): Calcinosis/anti-Centromere antibodies, Raynaud Phenomenon, Esophageal dysmotility, Sclerodactyly, and Telangiectasias of the skin
Disease affects the lower esophageal sphincter primarily, lack of peristalsis, dysphagia
Outpouching of pharyngeal mucosa through an acquired defect in the muscular wall (false diverticulum)
Arises above the upper esophageal sphincter at the junction of the esophagus and pharynx
Cause: disordered fxn of cricopharyngeal musculature
Presents with dysphagia, obstruction, and halitosis
Regurgitation of food eaten previously in absence of dysphagia
Zenker Diverticulum
Herniation of the stomach through an enlarged diaphragmatic opening
S/S: heartburn, regurgitation due to incompetence of LES
2 types:
1) cap of gastric mucosa move upward, above diaphragm due to enlargement of hiatus and laxity of circumferential CT, resolves on its own
2) portion of gastric fundus herniates through a defect in the diaphragmatic CT and lies beside the esophagus, extreme case = stomach herniates into thorax, these hernias need surgery
Hiatal Hernia
1) Sliding hernia
2) Paraesophageal hernia
Name it!
Transmural, usually distal esophageal rupture due to violent retching; surgical emergency
Leads to air in mediastinum, subcutaneous emphysema
Boerhaave syndrome
Name it!
Infiltration of esosinophils in the esophagus in atopic pts.
Food allergens lead to dysphagia, heartburn, strictures.
Sensation of food “sticking” upon swallowing
ID’d after found Unresponsive to GERD therapy
Eosinophilic esophagitis
1) associated with lye ingestion and acid reflux
2) Painless bleeding of dilated submucosal veins in lower 1/3 of esophagus 2ndary to portal HTN & cirrhosis, these veins are prone to rupture and hemorrhage
1) Esophageal strictures
2) Esophageal varices
Associated with reflux, infection in immunocompromised
Dysphagia, severe pain on swallowing
Can have Candida (white pseudomembrane), herpes (punched-out ulcers), CMV (linear ulcers) or be due to chemical ingestion
(Infective) esophagitis
Commonly presents as heartburn and regurgitation upon lying down. May also present with nocturnal cough and dyspnea, adult-onset asthma. Decrease in LES tone.
Gastroesophageal Reflux Disease
Mucosal lacerations at the gastroesophageal junction due to severe vomiting. Leads to painful hematemesis. Usually found in alcoholics and bulimics.
Mallory-Weiss Syndrome
Glandular metaplasia: replacement of nonkeratinized stratified squamous epithelium with intestinal epithelium (nonciliated columnar w/goblet cells) in the distal esophagus.
Due to chronic acid reflux (GERD)
Associated with esophagitis, esophageal ulcers, and increased risk of esophageal adenocarcinoma correlated with length of esophagus involved and the degree of dysplasia
Barrett Esophagus
Patient presentation: progressive dysphagia (first solids, then liquids) and weight loss, poor prognosis
2 Types of cancer? Usual locations for each?
Risk factors? AABCDEFFGH
Esophageal cancer
1) Squamous cell carcinoma = worldwide, upper 2/3 of esophagus, (achalasia, alcohol, cigs, diverticula (Zenker), esophageal web, hot liquids)
2) Adenocarcinoma = US, lower 1/3, (Barrett esophagus, cigs, Fat (obesity), GERD)
Others: familial
Hypertrophy of the pylorus causes obstruction.
Palpable “olive” mass in epigastric region
Nonbilious projectile vomiting in first month of life
Could lead to hypochloremic alkalosis (loss of HCl)
Most common indication for abdominal surgery in the 1st 6 months of life (treat: surgical incision)
More often in firstborn males
Congenital pyloric stenosis
Mucosal barrier breakdown/necrosis, may extend to deeper tissues forming ulcer = inflammation b/c permit acid-induced injury (hypersecretion of gastric acid usually)
Widespread petechial hemorrhages
Could be benign abdominal discomfort or full on hemorrhage
Causes:
Stress
NSAIDs (decreased PGE2 leads to decreased gastric mucosa protection)
alcohol
uremia
burns (decreased plasma volume leads to sloughing of gastric mucosa) SPECIAL NAME?
brain injury (Increased vagal tone => increased ACh => increased H+ production) SPECIAL NAME?
Acute gastritis (erosive)
Remember:
BURNED by the CURLING iron.
Always CUSHion the BRAIN.
Chronic, diffuse inflammatory disease of the body and fundus of stomach
Autoimmune disorder characterized by:
destruction of parietal cells, Autoantibodies to parietal cells & intrinsic factor, pernicious Anemia, and Achlorhydria
Associated with other autoimmune disorders: grave’s, addison, vitiligio, T1DM etc.
What’s pernicious anemia? No, really I don’t remember Unit 1. GAHHHHH.
Increased risk for what?
Autoimmune atrophic gastritis (chronic gastritis) Remember: type A (Autoimmune), type B (H. pylori Bacteria)
Pernicious anemia = megaloblastic anemia caused by malabsorption of Vit B12 owing to a deficiency of intrinsic factor.
Increased risk for gastric adenocarcinoma (intestinal type)
Break time. I dare you to stand up and dance to this for 30 seconds.
https://www.youtube.com/watch?v=VzSdPxlGGZc
Chronic inflammatory disease of antrum of stomach
PMNs, plasma cells
What is the most common cause of this disease?
What is there an increased risk for ?
Chronic gastritis
H. pylori found on epithelial surface of stomach (no invasion)
Increased risk of ulcercation, MALT lymphoma, and gastric adenocarcinoma
Gastric hypertrophy with protein loss (albumin), parietal cell atrophy, and increase mucous cells.
Hyperplastic hypersecretory gastropathy
Precancerous, need regular endoscopy
Rugae of stomach are so hypertrophied they look like brain gyri. ENLARGED RUGAE = enlarged stomach.
S/S: postprandial pain, relieved by antacids, weight loss, peripheral edema, maybe ascites
Menetrier disease
Normal flat mucosal surface of stomach replaced by villiform projections with fibromuscular proliferation in the lamina propria
Inflammation is minimal unlike H. pylori gastritis
Causes?
Reactive (Chemical) gastropathy
Chronic NSAID use
Focal destruction of gastric mucosa
Pain can be greater with meals = weight loss
H. pylori in 70%
Mechanism is decreased mucosal protection (due to H. pylori chronic gastritis causing epithelial injury) against gastric acid
These pts secrete waay less acid than normal ppl (gastric hyposecretion)
Other causes are NSAIDS
Increased risk of carcinoma
Often occurs in older patients
Peptic Ulcer Disease
Specifically Gastric Ulcer
Focal destruction of duodenal mucosa
Pain decreases with meals = weight gain
H. pylori infection in 100% (=> cytokines => increased gastrin release/decreased somatostatin => increased gastric acid secretion)
Mechanism is decreased mucosal protection or increased gastric acid secretion
Other causes are Zollinger-Ellison syndrome
Generally benign
Hypertrophy of Brunner glands
Seen in ppl with cirrhosis 10x than normal ppl
Peptic Ulcer Disease
Duodenal Ulcers
Tend to be nonagressive tumors in the stomach
Aggressive in small & large intestines
Overexpression of c-kit (gain of function mutation)
Derived from pacemaker cells of Cajal
Usually submucosal, covered by intact mucosa, spindle shaped cells in whorls and interlacing bundles w/cytoplasmic vacuoles embedded in a collagenous stroma
Gastrointestinal Stromal Tumors (GISTs)
What is the most important causative agent for stomach cancer and is implicated in about 2/3rds of cases?
H. pylori
H. pylori
Smoking
Nitrosamines
A diet high in starch, smoked, or cured fish and meat, pickled vegetables
Possible factors in carcinoma of stomach
Stomach cancer is almost always adenocarcinoma.
Early aggressive local spread and node/liver metastasis. Often presents with acanthosis nigricans.
Two types?
1) associated with H. pylori, dietary nitrosamines (smoked foods), tobacco smoking, achlorhydria, chronic gastritis. Commonly located on lesser curvature; looks like ulcer with raised margins, originate from areas of intestinal metaplasia
2) not associated with H. pylori, signet ring cells, stomach wall grossly thickened and leathery (linitis plastica)
1) Intestinal
2) Diffuse *linitis plastica = entire stomach involved
Difference in appearance of a benign peptic ulcer and an ulcerating adenocarcinoma?
Benign ulcer = punchout margins and a smooth base
Cancer = firm, raised and nodular, lateral margins are irregular and its base is ragged
Involvement of left supraclavicular node by metastasis from stomach
Virchow node
Bilateral metastases to ovaries, abundant mucus, signet ring cells
Krukenberg Tumor
Subcutaneous periumbilical metastasis
Sister mary joseph nodule
Endocrince cells in gastric mucosa may give rise to neoplasms
not usually hormonally active
Sometimes secrete 5-HT
Hypergastrinemia associated with autoimmune gastritis
Gastric neuroendocrine tumors (low grade malignancies)
Metastasis can cause carcinoid syndrome
Metastatic spread if level of esophagus carcinoma involved:
1) Upper 1/3
2) Middle 1/3
3) Lower 1/3
Lymph node spread
1) Cervical, internal jugular, supraclavicular
2) paratracheal, hilar, aortic, cardiac, paraesophageal (aka. mediastinal or tracheobronchial)
3) celiac, retroperitoneal and gastric nodes
True diverticulum
Persistence of the vitelline duct, outpouching of the gut on the antimesenteric ileal border
May contain ectopic acid-secreting gastric mucosa and/or pancreatic tissue
Most common congenital anomaly of the GI tract
Can cause Melena, RLQ pain, intussuception, volvulus, or obstruction near the terminal ileum
What are the five 2’s to remember?
Meckel Diverticulum
2 inches long
2 feet from the ileocecal valve
2% of population
Commonly presents in first 2 years of life
May have 2 types of epithelia (gastric/pancreatic)
How can you remember the malabsorption syndromes?
These Will Cause Devestating Absorption Problems
Tropical Sprue Whipple disease Celiac Sprue Disaccharide deficiency Abetalipoproteinemia Pancreatic Insufficiency
Why do you need to worry about CF patients with GI problems in neonatal period?
Highly viscous mucous may block the pancreatic duct and thicken intestinal contents
Tenacious meconium may accumulate and obstruct the small intestine
Infarcted bowel, becomes edematous and diffusely purple
Hemorrhage is prominent
Mucosal surface w/irregular white sloughs
Dysfxn of smooth muscle = interfere peristalsis => adynamic ileus (bowel proximal to the lesion is dilated and filled with fluid)
S/S: abrupt abdominal pain, bloody diarrhea, hematemesis, and shock (MODS)
Superior Mesenteric Artery Occlusion causes Acute Intestinal Ischemia
Atherosclerotic narrowing of major splanchnic arteries
intermittent abdominal pain
Pain starts w/i 1/2 hour of eating and lasts for a few hours
Eventually: fibrosis and stricture formation, obstruction, malabsorption due to stasis, bacterial overgrowth
Chronic Intestinal Ischemia aka intestinal angina
Autoimmune-mediated intolerance of gliadin (wheat) leading to malabsorption and steatorrhea.
Associated with HLA-DQ2 & 8
Anti-endomysial, anti-tissue transglutaminase, and anti-gliadin antibodies
Blunting of villi, crypt hyperplasia, lymphocytes in lamina propria
Decreased mucosal absorption that primarily affects distal duodenum and/or proximal jejunum
Dx: tissue transglutaminase antibodies
Association with dermatitis herpetiformis
What is there an increased risk of developing?
Celiac sprue
Increased risk of malignancy (T-cell lymphoma and small bowel carcinoma) if refractory to good dietary control.
Systemic tissue damages w/ Infection with Tropheryma whipplei (Gram +)
PAS +
Foamy macrophages containing partially destroyed organisms in intestinal lamina propria, mesenteric nodes causing compression of lacteals => fat malabsorption and steatorrhea
Cardiac valves, Arthralgias, and Neurologic symptoms, lymph nodes
Occurs in Older men
Whipple Disease
Remember: Foamy whipped cream in a CAN
Most common is lactase deficiency => milk intolerance Normal appearing villi Osmotic diarrhea (due to lactose) Also self-limited lactase deficiency occurs following injury (viral, diarrhea) Lactose tolerance test is + for deficiency if: giving lactose produces symptoms and glucose rises
Disaccharidase deficiency
Autosomal Recessive deficiency of apolipoprotein B-48 (defective chylomicron formation) and B-100 (absent plasma VLDL and LDL)
Fat accumulation in enterocytes
Child: failure to thrive, steatorrhea, acanthocytosis, ataxia, night blindness
Abetalipoproteinemia
Due to cystic fibrosis, obstructing cancer and chronic pancreatitis.
Causes malabsorption of fat and fat soluble vitamins (ADEK)
Increased neutral fat in stool
Use D-xylose absorption test:
1) normal urinary excretion in pancreatic insufficiency
2) Decreased excretion w/intestinal mucosa defects or bacterial overgrowth
Pancreatic insufficiency
Malignant proliferation of neuroendocrine cells
+ for chromogranin
Small bowel most common site
Submucosal polyp-like nodule
Secretes 5-HT (metabolized by liver MAO to 5-HIAA then excreted in urine)
If this tumor metastasizes: 5-HT bypasses liver metabolism so result is _____ syndrome.
Characterized by: bronchospasm, diarrhea, flushing of skin, triggered by EtOH/stress
Carcinoid Tumor (now being called neuroendocrine tumor more often) Carcinoid syndrome
What is carcinoid heart disease?
R-sided valvular fibrosis (increased collagen) leading to tricuspid regurgitation and pulmonary valve stenosis. L-sided valvular lesion not seen b/c lung MAO metabolizes the 5-HT.
Result of metastasis of carcinoid tumor
Etiology: Disordered response to intenstinal bacteria maybe
What: full thickness inflammation w/knife-like fissures
Location: any portion of GI tract, usually terminal ileum, SKIP lesions, RECTAL SPARING
Symptoms: RLQ pain with nonb-or-bloody diarrhea
Grossly: COBBLESTONE mucosa, creeping FAT, bowel wall thickening, string sign on barium swallow due to strictures, transmural inflammation => fistulas
Histology: Lymphoid aggregates with noncaseating GRANulomas (Th1 mediated)
Complications: strictures => obstruction, perianal disease, fistulas, malabsorption w/nutritional def, calcium oxalate nephrolithiasis, colorectal cancer, gallstones
Crohn Disease
Remember: think of a FAT GRANny and an old CRONE SKIPping down a COBBLESTONE road away from the WRECK (rectal sparing)
Migratory polyarthritis, erythema nodosum, ankylosing spondylitis, pyoderma grangrenosum, apthous ulcers, uveitis, kidney stones
Associations of what?
Association unique to this?
Crohn disease kidney stones (calcium oxalate)
Treatment for Crohn disease?
Corticosteroids, azathioprine, methotrexate, infliximab, adalimumab
Etiology: Autoimmune
What: colon inflammation, always rectal involvement
Location: Begins in rectum, can extend up to the cecum, remainder of GI unaffected
Symptoms: LLQ pain (rectum) with bloody diarrhea
Grossly: mucosal and submucosal ulcers, friable mucosal pseudopolyps w/freely hanging mesentary, lead pipe sign on imaging b/c loss of haustra
Histology: crypt abscesses with neutrophils and ulcers, bleeding, no granulomas (Th2 mediated)
Complications: Malnutrition, toxic megacolon, colorectal carcinoma (worse w/right sided colitis or pancolitis, concern with >10 yrs, risk based on extent&duration)
Ulcerative Colitis
Remember: ULCCCERS Ulcers Large Intestine Continuous Colorectal carcinoma Crypt abscess Extends proximally Red diarrhea Sclerosing cholangitis
Primary sclerosing cholangitis, p-ANCA, ankylosing spondylitis, sacroilitis, migratory polyarthritis, apthous ulcers, uveitis, erythema nodosum, pyoderma gangrenosum
Associations of what?
Association unique to this?
Ulcerative colitis
Primary sclerosing cholangitis
Treatment for Ulcerative colitis?
ASA preparations (sulfasalazine)
6-mercaptopurine
infliximab and colectomy
Acute inflammation of the appendix
Due to:
1) In child?
2) In adult?
S/S: initial diffuse periumbilical pain migrates to McBurney point (1/3 distance from the anterior superior iliac spine to umbilicus), fever, nausea.
Rupture of appendix will result in what? The signs?
Appendicitis
1) Lymphoid hyperplasia (can follow GI infections)
2) Fecalith
Rupture: peritonitis, may see psoas, obturator, and Rovsing signs, guarding, rebound tenderness
periappendiceal abscess is a common complication
Defective relaxation and peristalsis of rectum and distal sigmoid colon (rectum permanently contracted)
Associated with Down Syndrome
Results from congenital failure of ganglion cells (neural crest derived) to descend into the wall (missing Myenteric plexus and Auerbach plexus)
What do these nerve plexuses do?
RET gene mutation (congenital)
Chaga’s disease (destroy’s ganglion cells = megacolon)
S/S: bilious emesis, abdominal distention and failure to pass meconium 1st 24 hrs of life, empty rectal vault on DRE, Congenital megacolon proximal to obstruction could rupture
Hirschsprung Disease
Myenteric = regulates motility
Auerbach = regulates blood flow, secretions, and absorption
Outpouchings of mucosa and submucosa through the muscularis propria
Related to wall stress, constipation, straining, and low-fiber diet, risk increases with age
Arise where vasa recta traverse the muscularis propria
Colonic diverticula
Acquired malformation of mucosal and submucosal capillary beds
Usually in cecum and ascending colon due to high wall tension
Rupture presents as hematochezia
Angiodysplasia
ischemic damage to colon
Watershed infarct at the splenic flexure
atherosclerosis of SMA a common cause
Postprandial pain and weight loss, infarction results in pain and bloody diarrhea
ischemic colitis
“angina”
Relapsing abdominal pain with bloating, flatulence, and change in bowel habits (diarrhea or constipation) that improves with defecation
Classically in middle-age females
Disturbed intestinal motility, no identifiable pathological changes
Increase dietary fiber to improve symptoms
Irritable Bowel Syndrome
colonic polyps (>50% rectosigmoid colon) serrated appearance on microscopy (increased risk for adenocarcinoma) but otherwise benign most common type usually arise in L colon benign, no malignant potential
hyperplastic colonic polyps
neoplastic proliferation of glands
2nd most common type of colonic polyp
benign, but PREMALIGNANT (precursor to colorectal carcinoma)
Risk increases with size, villious histology, epithelial dysplasia
S/S: aymptomatic, lower GI bleed, partial obstruction, secretory diarrhea
Adenomatous colonic polyps
Progress to adenocarcinoma via adenoma-carcinoma sequence
Remember: villious = villanous
What are the 4 steps of the adenoma-carcinoma squence?
1) APC mutation (sporadic or germline), increased risk of polyp formation
2) K-ras mutation leads to formation of polyp
3) DCC knocked out (late adenoma)
4) p53 mutation and increased expression of COX = carcinoma
What impedes the progression from adenoma to carcinoma in the adenoma-carcinoma sequence?
Aspirin! taken to inhibit the COX
AD disorder with 100s-1000s of adenomatous colonic polyps, pancolonic, rectum
Inherited APC mutation (chr 5) increases likelihood of the “2nd hit” mutation to develop polyps
Carcinoma develops by age 40
100% progress to CRC unless colon resected
Familial Adenomatous Polyposis (FAP)
FAP with fibromatosis (non-neoplastic proliferation of fibroblasts) and osteomas (usually arise in skull, benign tumor of bone)
Gardner syndrome
FAP with CNS tumors (medulloblastoma and glial tumors)
Turcot syndrome
Remember: Turcot = Turban (head/CNS)
Hamartomatous (disorganized normal tissue, benign) polyps in children
Juvenile polyp/polyposis
Hamartomatous polyps throughout GI
Mucocutaneous hyperpigmentation (freckle-like spots) on lips, oral mucosa, genital skin
AD disorder
Increased risk of colorectal, breast, and gynecologic cancer
Peutz-Jeghers Syndrome
What are the two pathways that colorectal carcinoma may arise?
Adenoma-carcinoma sequence
Microsatellite instability
AD disorder
Inherited mutations in DNA mismatch repair enzymes causes microsatellite instability
Colorectal carcinoma arises de novo (not from adenomatous polyps) at relatively early age, usually right sided, proximal colon involved
80% progress to CRC
HNPCC (hereditary nonpolyposis colorectal carcinoma) aka Lynch Syndrome
Increased risk for colorectal, ovarian, and endometrial carcinoma
Napkin ring lesion
Decreased stool caliber (change in bowel habits)
LLQ pain, blood streaked stool
Usually due to adenoma-carcinoma sequence
Left sided colorectal carcinoma
remember: Right side bleeds, left side obstructs
Grows as a raised lesion Iron deficiency anemia (occult bleeding) Fatigue, weakness Vague pain Usually due to microsatellite instability
Right sided colorectal carcinoma
remember: Right side bleeds, left side obstructs
Colorectal carcinoma is associated with what microbe?
Streptococcus bovis which causes subacute endocarditis, bacteremia
Fibrous band of scar tissue
Forms after surgery
Most common cause of small bowel obstruction
Can have well-demarcated necrotic zones
Adhesion
Early bilious vomiting w/proximal stomach distention (double bubble on X-ray) b/c of failure of small bowel recanalization
Associated with Down syndrome
Duodenal atresia
Reduction in intestinal blood flow causes ischemia
Pain after eating => weight loss
Commonly occurs at splenic flexure and distal colon
Affects elderly typically
Ischemic colitis
In cystic fibrosis, meconium plug obstructs intestine, preventing stool passage at birth
Meconium ileus
Necrosis of intestinal mucosa and possible perforation
Colon is usually involved, but can involve entire GI tract.
In neonates, more coomon in preemies (decreased immunity)
Necrotizing enterocolitis
What are you suspicious of?
Fe deficiency anemia in males (>50) and in Postmenopausal females
Apple core lesion on barium enema
Colorectal cancer
Gastrin secreting tumor of pancreas or duodenum
Acid hypersecretion (due to HIGH gastrin) causes recurrent ulcers in distal duodenum and jejunum
PResents with abdominal pain (peptic ulcer disease, distal ulcers)
diarrhea (malabsorption)
May be associated with MEN1
Zollinger-Ellison Syndrome
