GI Flashcards
Esophageal atresia with TEF
Blind ending esophagus, with connection below to trachea. Polyhydramnios in utero. Neonate drool, choke, and vomit on first feeding. TEF allows air to enter stomach. Cyanosis due to layrngospasm (to avoid reflux-related aspiration)
Duodenal atresia -
Failure of recanalization - dilation of stomach and proximal duodenum (DOUBLE BUBBLE). Associated with down syndrome. Bilious vomiting
Hypertrophic Pyloric stenosis
Nonbilious projectile vomiting. Common in firstborn males
Metabolic alkalosis. Can be associated with exposure to macrolides
Annular pancreas
Ventral pancreatic bud encircles 2nd part of duodenum - can cause duodenal narrowing and nonbilious vomiting.
Retroperitoneal structures
SAD PUCKER - suprarenal, aorta and IVC, duodenum (2-4th parts), pancreas (except tail), ureters, colon (descending and ascending), kidneys, esophagus (thoracic portion), rectum (partially).
Lymph drainage above and below pectinate line
Above; internal iliac
Below: superficial inguinal
Diaphragmatic hernia
Abdominal structures enter thorax - maybe due to congenital defect of pleuroperitoneal membrane, or trauma. Commonly on left side (right protected by liver)
Most commonly a hiatal hernia - stomach herniated upward through esophageal hiatus of diaphragm.
Gastrin
G cells (Ancrum of stomach, duodenum), increased H+ secretion, growth of gastric mucosa, gastric motility. Increased release by stomach distention, alkalinazaion, amino acids, peptides vagal stim via GRP. Increased by chronic PPi use, in atrophic gastritis, in zollinger ellison syndrome.
VIPoma
Non alpha, non beta islet cell pancreatic tumour - secrets VIP. Watery diarrhoea, hypokalemia, achlorydia.
VIP increases intestinal water and electroylte secretion, relaxation of intestinal smooth muscle and sphincters.
Zollinger Ellison Syndrome
Gastrinoma, increase in gastrin. Gastrin increases H+ secretion, growth of gastric mucosa, and gastric motility.
Location of iron, folate, and B12 absorption
Iron: Fe2+ in duodenum
Folate: In small intestine
B12: terminal ileum along with bile salts, requires intrinsic factor (lack of IF–> pernicious anemia)
Achalasia
Failure of relaxation of LES due to loss of myenteric (auerbach plexus). High LES resting P and uncoordinated or absent peristalsis. Progressive dysphasia to solids and liquids.
Dilated esophagus with distal stenosis.
Meckel’s diverticulum
persistence of the vitelline duct. 2x more likely in males, 2 inches long, 2 ft from ileocecal valve, 2% of population.
Familial Adenomatous Polyposus
AD mutation of APC tumour suppressor gene on chromosome 5q. 2 hit hypothesis. Thousands of polyps after puberty, always involves rectum.
Lynch Syndrome (HNPCC).
AD mutation of DNA mismatch repair genes with subsequent microsatellite instability.
Serum markers of liver pathology
most liver disease: ALT>AST
Alcoholic: AST>ALT
Gamma glutamate transpeptidase: increased in liver and biliary disease, but NOT bone disease.
Non alcohoholic fatty liver: ALT>AST