GI Flashcards
What is within the spleen-renal ligament?
Splenic artery and tail of the pancreas
Where are the most Goblet cells found in the small intestine?
Ileum (duodenum has Brunner’s glands)
What is SMA Syndrome?
Intestinal obstruction that occurs when the duodenum gets pinched between the SMA and aorta
What do the I, G, K, S, and D cells in the GI tract secrete?
I - CCK G - gastrin K - GIP (potentiates insulin release) S - secretin D - SST
What electrolyte abnormality is associated with PUD and GERD?
HyperCa - increases gastrin secretion
What regulatory signal produces Migrating Motor Complexes? What antibiotic also stimulates this?
Motilin
Erythromycin
What regulatory signal is essential for pancreatic enzyme function in the duodenum?
Secretin - stimulates pancreatic HCO3 (neutralize gastric acid to prevent enzyme degradation) and gallbladder bile secretion (break up fats into digestible micelles)
What increases gastric parietal cell HCl secretion and through which GCPR?
ACh (M3 = Gq), Gastrin (Gq), Histamine (Gs)
What NT is released from the the vagus nerve to stimulate G cell gastrin secretion?
GRP (gastrin releasing peptide) - Atropine doesn’t completely block gastric acid secretion
What do intestinal SGLT1 and GLUT5 transport? How are they transported into the blood?
SGLT1 - Na and glucose or galactose
GLUT5 - fructose
Secreted into blood by GLUT2
What does the D-xylose absorption test distinguish?
Malabsorption due to GI mucosal damage (increased fecal D-xylose) versus pancreatic enzyme insufficiency/inactivation (normal fecal D-xylose)
How is Cu eliminated from the body?
Excretion into the bile
What 4 GI problems are Down Syndrome patients predisposed to?
Duodenal atresia, annular pancreas, celiac disease, Hirschsprung disease
Does sympathetic stimulation of salivary glands produce a thick or waters saliva? Where does the signal come from? Parasympathetic?
Sympathetic - thick, superior cervical ganglion
Parasympathetic - watery, CN 7 and 9
What salivary tumor is most common?
Pleomorphic adenoma (cartilage + epithelium)
What malignant salivary tumor is most common?
Mucoepidermoid CA (mucinous + squamous)
What benign salivary tumor has germinal centers and bi-layered epithelium?
Warthin tumor
Plummer-Vinson Syndrome
Esophageal webs, Fe deficiency anemia, glossitis
What may be the diagnosis in someone with heartburn that is unresponsive to GERD therapy?
Eosinophilic esophagitis - due to food allergen in patients with atopic diseases. May lead to strictures
Esophageal strictures is associated with ingestion of what substance?
Lye
What type of esophageal cancer are cigarettes, esophageal webs, and obesity risk factors for?
Cigarettes - both
Esophageal webs - squamous cell
Obesity - adenoCA
What is a curling ulcer? Cushing ulcer?
Curling ulcer = burns (decreased plasma volume leads to mucosal ischemia and sloughing) “curling iron burns”
Cushing ulcer = brain injury (increased vagal stimulation)
What are the 2 most common causes of acute gastritis?
NSAIDs and alcohol
What causes type A chronic gastritis? Type B? What type of cancers are increased in each?
Type A - autoimmune destruction (therefore also pernicious anemia). Increased risk gastric adenoCA
Type B - H pylori infection. Increased risk gastric adenoCA and MALToma
“A = autoimmune, B = bacteria”
What is Menetrier disease?
Precancerous hypertrophy of mucus cells with parietal cell atrophy. Decreased acid production leads to enteric protein loss and edema. Stomach rug look like brain gyri
Dietary intake of what food is associated with intestinal-type gastric adenoCA?
Nitrosamines (smoked foods)
If a duodenal ulcer ont he posterior wall ruptures, what vessel would bleed?
Gastro-duodenal artery
What is Triple Therapy for H pylori?
PPI + clarithromycin + amoxacillin or metronidazole
What is Quadruple therapy for H pylori?
PPI + metronidazole + bismuth + tetracycline
How is Tropical Sprue different from celiac sprue?
Responds to abx, thus infectious (although exact bug is not known)
How does Whipple Disease present? What stain is used to identify the organism?
“Whipped cream in a CAN” - cardiac symptoms, arthralgia, neurologic symptoms
PAS acid-Schiff stains positively in foamy macrophages
What HLA genes are associated with Celiac sprue?
HLA-DQ2 and HLA-DQ8
How would Celiac sprue affect stool pH?
Decrease pH (undigested lactose is fermented by colonic bacteria into short chain FAs + H causing acidosis and an osmotic diarrhea)
What is the mechanism of disease in abetalipoproteinemia?
Deficiency ApoB48 causes CMs to be stuck in the enterocytes. Inability to absorb fats leads to fat-vitamin deficiencies
What hematologic abnormality is seen in abetalipoproteinemia?
Acanthocytes (star-shaped RBCs)
What renal complication is associated with Chron disease?
Nephrolithiasis (oxalate stones) - decreased bile repute increases lipid content = saponification with fecal Ca = less free Ca to bind oxaloacetate and prevent absorption = supersaturation and stone formation
What rheumatoid conditions are associated with both Chrons and UC?
Seronegative spondyloarthropathies (HLA-B27) "PAIR" - Psoriatic arthritis, ankylosing spondylitis, IBD, reactive arthritis
What is the most common cause of appendicitis in children?
Lymphoid hyperplasia and obstruction
How would you diagnose a Meckel Diverticulum?
Pertechnate study - measure radiolabelled pertechnate uptake by gastric tissues. If it labels are portion of the intestine, there is ectopic gastric mucosa due to Meckel Diverticulum
What pathology is associated with currant jelly stools?
Intussusception
What are the 3 most common causes of bowel obstruction?
Adhesions, hernias, and cancer
What gene mutation is associated with Hirschsprung disease?
RET
What is angiodysplasia?
Tortuous dilation of vessels in the GI tract. Causes hematochezia (bright red blood) and is found in elderly patients
What pathology is associated with patient reported abdominal pain that is out of proportion of physical exam findings?
Ischemic colitis
What pathology is associated with apple peel intestinal architecture?
Atresia due to vascular accident in newborns
What causes abundant mucinous secretory diarrhea (that is non-infectious)?
Villous-type adenomatous polyp
Single mass lesion in the rectum of a young child
Juvenile polyp
What is Peutz-Jeghers syndrome?
Many non-malignant hamartomatous polyps in GI tract + hyperpigmention of mouth and hands
DOES increase risk of colorectal CA
What is Gardener Syndrome?
FAP + osteomas + soft tissue tumors
What is Turcot syndrome?
FAP + medulloblastoma
“Turcot = turban”
What is the mutation in HNPCC/Lynch syndrome?
DNA repair genes - leads to microsatellite instability
What is the tumor marker used to monitor recurrence of colorectal cancer?
CEA
What sequence of mutations (4) leads to non-inherited colorectal CA?
APC (tumor supressor) - Kras (oncogene) - p53, DCC
What enzyme may contribute to progression of colorectal CA?
COX2 - aspirin may be protective
What gastric pathology is associated with cirrhosis and why?
Portal HTN causes congestion - decreased perfusion to the stomach weakens/thins the mucosa predisposing to peptic ulcers
How does Reye syndrome present? What is damaged?
Hypoglycemia + hepatomegaly (fatty liver) + encephalopathy
Asprin damages the mitochondria
What pathology is associated with Mallory bodies?
What are Mallory bodies?
Alcoholic hepatitis
Damaged intermediate filaments
What carcinogen is associated with HCC?
Aflatoxin (from Aspergillis)
What is the tumor marker used to monitor recurrence of HCC?
AFP
What paraneoplastic syndrome is associated with HCC?
Polycythemia (EPO production)
Arsenic and vinyl chloride exposure predispose to what liver pathology?
Angiosarcoma (malignant endothelial tumor)
What 2 antibodies are associated with type 1 Autoimmune hepatitis?
ANA and anti-smooth-muscle
What 2 antibodies are associated with type 2 Autoimmune hepatitis?
Anti-liver/kidney-microsomal and anti-liver-cytosol
What is the greatest concern with Echinococcus granulizes infection?
Can form liver abscess (tapeworm). If ruptured during removal or biopsy could trigger anaphylactic shock
What pathology is associated with PAS+ globules within hepatocytes?
Alpha 1 antitrypsin deficiency
Which type of Crippler-Najjar syndrome is responsive to phenobarbital?
Type 2 (some UDP-glucuronosyltransferase activity remains)
What hereditary hyperbilirubinemia is associated with a grossly black liver?
Dubin-Johnson syndrome
What CNS changes are associated with Wilson disease?
Parkinsonism (degeneration of the basal ganglia)
What genetic mutation is associated with Wilson disease?
Defective hepatocyte Cu transporting ATPase (ATP7B)
What pathology is associated with bronze diabetes?
Hemochromatosis
What is seen on histology in Primary Biliary Cirrhosis?
Lymphocytic infiltrate with granulomas
What antibodies are associated with PBC?
Anti-mitochondrial (AMA)
What is seen on histology in Primary Sclerosing Cholangitis?
Concentric onion skinning of bile ducts, “beads on a string” intra and extra-hepatic bile ducts
What antibodies are associated with PBC? What other autoimmune disease is associated with PSC?
pANCA
Ulcerative colitis
What pathology is associated with RUQ pain radiating to the right scapula?
Acute cholecystitis
What pathology is associated with Rokitansky-Aschoff sinuses?
Chronic cholecystitis (herniation of gallbladder mucosa into the muscular wall)
What should be considered in an elderly female presenting with new onset cholecystitis?
Gallbladder adenoCA
What hematologic pathology is associated with pigmented gallstones?
Hemolytic anemia - bilirubin stones
How does Clofibrate increase the risk for cholesterol gallstones?
Decreases bile acid production
What is Charcot’s triad?
RUQ pain + jaundice + fever (also associated with HoTN and altered mental status) indicating cholangitis (inflammation of the biliary tree)
What viral infection is associated with acute pancreatitis?
What drugs can cause acute pancreatitis?
Mumps
Sulfa drugs and HIV NRTIs/PIs
ALSO scorpion sting!
What tumor markers are used in pancreatic adenoCA?
CA 19-9 and CEA
What is Trousseau syndrome? What pathology is associated with it?
Migratory thrombophlebitis
Pancreatic adenoCA
What is the mechanism of action of Metoclopramide? What is it’s clinical use?
Increases 5HT4 and decreases D2 in the GI tract
Diabetic gastroparesis
What are the side effects of Cimetidine?
P450 inhibitor, anti-androgen
Which antacid causes constipation and which causes diarrhea?
Aluminum OH = constipation “alu-minimum”
Magnesium OH = diarrea “Mg = must go”
What drug is used to treat the seronegative spondyloarthropathies (including IBD)?
Infliximab (anti-TNFa Abs)
What two types of necrosis are present in acute pancreatitis?
Liquefactive (pancreatic tissue) and fat (surrounding adipose tissue)
What skin findings are seen with acute pancreatitis?
Periumbilical and flank hemorrhages (migrates into the retroperitoneal fat
Infection with what organism can cause fulminant liver failure in a pregnant woman?
Hepatitis E
What are the causes of acute pancreatitis?
“pancreatit-s”
hyperParathyroid (hyperca), Alcohol, Neoplasm (obstructive), Cholelithiasis, Rx (HIV, sulfa drugs), ERCP, Abdominal surgery, Trauma, Infection (mumps), hyperTriglycerides, and Scorpion sting
What is the mechanism of orlistat?
Pancreatic lipase inhibitor (Alli weight loss drug)