Random facts Flashcards
Omphalocele, gastroschesis due to failure of
Lateral fold closure
Bladder exstrophy due to failure of
Caudal fold closure
Sternal defects due to failure of
Rostral fold closure
Embryology of spleen
Arises in mesentery of stomach (hence is mesodermal) but is supplied by foregut (celiac artery)
What is the portal triad contained within?
Hepatoduodenal ligament
What is the Pringle maneuver?
Compressing the hepatoduodenal ligament (and therefore the portal triad to control bleeding) between the thumb and index finger in mental foramen
What is contained in the gastrohepatic ligament?
Gastric arteries
What is contained in the gastrocolic ligament?
Gastroepiploic arteries
What is contained in the gastrosplenic ligament?
Short gastric, left gastroepiploic vessels
What is contained in the splenorenal ligament?
Splenic artery and vein, tail of pancreas
What are the three zones of the liver anatomy?
Zone 1- periportal (branch of portal vein and hepatic artery- bringing blood IN); zone 2- intermediate zone; zone 3- pericentral vein (centrilobular) zone (branch of hepatic vein- taking blood OUT)
Which way do blood and bile flow in the liver?
Blood flows from zone 1-> zone 3; bile flows from zone 3-> zone 1
Which zone is affected first by viral hepatitis?
Zone 1
Which zone is affected first by ingested toxins?
Zone 1
Which zone is affected by yellow fever?
Zone 2
Which zone is affected first by ischemia?
Zone III
Which zone contains the cytochrome P450 system?
Zone III
Which zone is most sensitive to metabolic toxins?
Zone III
Which zone is the site of alcoholic hepatitis?
Zone III
What produces gastrin and where are they located?
G cells (antrum of stomach, duodenum)
Action of gastrin
Increased gastric secretion, increase growth of gastric mucosa, increase gastric motility
What produces somatostatin and where are they located?
D cells (pancreatic islets, GI mucosa)
Action of somatostatin
Decrease gastric acid and pepsinogen secretion, decrease pancreatic and SI fluid secretion, decrease gallbladder contraction, decrease insulin and glucagon release
What produces cholecystokinin and where are they located?
I cells (duodenum, jejunum)
Action of cholecystokinin
Increase pancreatic secretion, increase gallbladder contraction, decrease gastric emptying, increase sphincter of Oddi relaxation
What produces secretin, and where are they located?
S cells (duodenum)
Action of secretin
Increase pancreatic HCO3- secretion, decrease gastric acid secretion, increase bile secretion
What produces GIP and where are they located?
GIP= Glucose-dependent insulinotropic peptide (aka Gastric inhibitory peptide) K cells (duodenum, jejunum)
Function of GIP
Exocrine: decrease gastric H+ secretion
Endocrine: Increase insulin release
Symptoms of a VIPoma
Watery Diarrhea, hypokalemia, and achlorhydria
What produces Intrinsic factor, and where are they located?
Parietal cells (upper glandular layer of the stomach)
What produces gastric acid, and where are they located
Parietal cells (upper glandular layer of the stomach)
What produces pepsin, and where are they located?
Chief cells (in the deep glands of the stomach)
What is the action of pepsin?
Protein digestion
Primary mechanism of gastrin increasing acid secretion
Through its effects on enterochromaffin-like cells (leading to histamine release)
How are glucose and galactose taken up from the gut?
SGLT1 (Na-dependent)
How is fructose taken up from the gut?
GLUT-5 (facilitated diffusion)
How do glucose, galactose, and fructose get into the blood from the enterocytes?
GLUT-2
What catalyzes the rate-limiting step in bile synthesis?
Cholesterol 7-alpha-hydroxylase
What is heme metabolized by?
Heme oxygenase to biliverdin (which is reduced to bilirubin)
What enzyme is used to conjugate indirect bilirubin?
UDP-glucuronosyl-transferase (in the liver)
Direct bilirubin is conjugated with glucuronic acid
Most common salivary gland tumor?
Pleomorphic adenoma
Composed of chondromyxoid storm and epithelium
Recurs if incompletely excised or ruptured intraoperatively
What is a benign cystic tumor with germinal centers?
Warthin tumor (papillary cystadenoma lymphomatosum)
What is MC malignant salivary tumor?
Mucoepidermoid carcinoma (has mutinous and squamous components)
What is a curling ulcer?
Burns–> decreased plasma volume –> sloughing of gastric mucosa
What is a Cushing ulcer?
Brain injury–> increased vagal stimulation –> increased ACh –> increased H+ production
What is Menetrier disease
Gastric hyperplasia of mucosa-> hypertrophied rugae, excess mucus production with resultant protein loss and parietal cell atrophy with decreased acid production. Precancerous
What do you see in Whipple disease?
Gram positive, rod-shaped bacilli, PAS + foamy macrophages in intestinal lamina propria, mesenteric nodes. Cardiac symptoms, arthralgias, and neurologic symptoms are common
Treatment for Crohn disease
Corticosteroids, azathioprine, antibiotics (eg. ciprofloxacin, metronidazole), infliximab, adalimumab
Treatment for Ulcerative colitis
5-aminosalicylic preparations (eg. mesalamine), 6-mercaptopurine, infliximab, colectomy
Which IBD is associated with sclerosing cholangitis?
Ulcerative colitis
What is a Zenker diverticulum?
Pharyngeoesophageal false diverticulum. Herniation of mucosal tissue at Killian triangle between the thyropharyngeal and cricopharyngeal parts of the inferior pharyngeal constrictor
Where is the APC gene located?
Chromosome 5q
What is Gardner syndrome?
FAP + osseous and soft tissue tumors, congenital hypertrophy of retinal pigment epithelium, impacted/supernumerary teeth
What is Turcot syndrome?
FAP + malignant CNS tumor
What is Peutz-Jeghers syndrome associated with?
Hyper pigmented mouth, lips, hands, genitalia. Increased risk of colorectal, breast, stomach, small bowel, and pancreatic cancers
What is Lynch syndrome?
AD mutation of DNA mismatch repair genes with subsequent micro satellite instability; associated with endometrial, ovarian, and skin cancers
Most common molecular pathogenesis of colorectal cancer
Loss of APC gene causes decreased intercellular adhesion and increased proliferation –> methylation abnormalities–> COX-2 overexpression–> KRAS mutation causing unregulated intracellular signal transduction –> adenoma –> Loss of tumor suppressor genes (p53, DCC) causing increased tumorigenesis –> carcinoma
Mechanism of Reye syndrome
Aspirin metabolites decrease beta-oxidation by reversible inhibition of mitochondrial enzymes
What are Mallory bodies?
Intracytoplasmic eosinophilic inclusions of damaged keratin filaments, seen in alcoholic hepatitis
Diagnosis of HCC?
Increased alpha-fetoprotein, 3 phase MRI
Causes of unconjugated hyperbilirubinemia
Hemolytic, physiologic, Crigler-Najjar, Gilbert syndrome
Causes of direct hyperbilirubinemia
Biliary tract obsruction (gallstone, cholangiocarcinoma, pancreatic or liver cancer, liver fluke); biliary tract disease (primary sclerosis cholangitis, primary biliary cirrhosis), excretion defect (Dubin-Johnson syndrome, Rotor syndrome)
Crigler-Najjar syndrome, type I
Absent UDP-glucuronoyl transferase. Presents early in life; patients die within a few years. Findings: jaundice, kernicterus, increased unconjugated bilirubin. Tx: plasmapheresis and phototherapy
Type II is less severe and response to phenobarbital
Dubin-Johnson syndrome
Conjugated hyperbilirubinemia due to defective liver excretion. Grossly black liver. Benign
Rotor syndrome
Conjugated hyperbilirubinemia. Does NOT cause a black liver
Pathology of PBC
Autoimmune rxn –> lymphocytic infiltrate +granuloma -> destruction of interlobular bile ducts
Pathology of PSC
Unknown cause of concentric “onion skin” bile duct fibrosis -> alternating strictures and dilation with “beading” and intra- and extra-hepatic mile ducts
Associated with PSC
Ulcerative colitis. May also see hypergammaglobulinemia (IgM). MPO-ANCA/p-ANCA positive. Can lead to secondary biliary cirrhosis, cholangiocarcinoma
Charcot triad of cholangitis
Jaundice, fever, RUQ pain
Causes of acute pancreatitis
idiopathic, Gallstones, Ethanol, Trauma, Steroids, Mumps, Autoimmune disease, Scorpion sting, Hypercalcemia/Hypertriglyceridemia, ERCP, Drugs . (GET SMASHED)
Why do patients with sarcoid or Beryllium exposure have hypercalcemia?
Because the epithelioid histiocytes of the non-caveating granulomas produce 1-alpha hydroxyls that converts vitamin D to its active form
Triad of Behcet syndrome
Aphthous ulcers, genital ulcers, and uveitis
What is anisocytosis?
Varying size
What is poikilocytosis?
Varying shapes
What does the platelets contain?
Dense granules (ADP, Ca) and alpha granules (vWF, fibrinogen)
What are the neutrophil chemotactic agents?
C5a, IL-8, LTB4, kallikrein, platelet-activating factor
What are causes of eosinophilia?
Neoplasia, Asthma, Allergic processes, Chronic adrenal insufficiency, Parasites
What do eosinophils produce?
histaminase and major basic protein (a helminthotoxin)
What do basophil granules contain?
Heparin and histamine
When might you see basophilia?
Myeloproliferative disease, especially CML
What does cromolyn sodium do?
Prevents mast cell degranulation
What type of immunoglobulin are Anti-A and Anti-B
IgM
What does warfarin inhibit?
Vitamin K epoxide reducatase
What drugs inhibit ADP induced expression of GpIIb/IIIa?
Clopidogrel, prasugrel, and ticlopidine
What has a failure of agglutination with rstocetin assay?
von Willebrand disease and Bernard- Soulier syndrome
When might you see basophilic stippling?
Lead poisoning
Orotic aciduria
Defect in UMP synthase. Inability to convert orotic acid to UMP (de novo pyrimidine synthesis pathway). No hyperamonemia (vs. ornithine transcarbamylase deficiency)
Treatment of orotic aciduria
Uridine monophosphate
Hemolytic anemia in a newborn
Pyruvate kinase deficiency
Treatment of PNH
eculizumab
Warm agglutinin
Chronic anemia seen in SLE and CLL with certain drugs (e.g., alpha-methyldopa)
Cold agglutinin
Acute anemia triggered by cold, seen in SLL, mycoplasma pneumonia infections, and infectious mono
Corticosteroid effect on WBCs
Neutrophilia (because decreased margination), but eosinopenia (sequester in lymph nodes) and lymphopenia (cause apoptosis)
When does OR=RR?
If prevalence is low
What can predispose to long QT interval
Drugs (antiarrhythmics 1a and 3, antibiotics like macrolides, antipsychotics, antidepressants like TCAs, and antiemetics like ondansetron), hypokalemia, hypomagnesemia
Inheritance of the long WT syndromes
Romano-Ward is autosomal dominant. Jervell and Lange-Nielson is autosomal recessive (with sensorineural deafness)
What is Brugada syndrome
Autosomal dominant disorder in Asian mAles. Pseudo-right bundle branch block and ST segment elevations in V1-V3. Tx:ICD
Potential cardio effect of Lyme disease
3rd degree heart block
What local metabolites in the heart cause vasodilation
Adenosine, NO, CO2, decreased O2
What local metabolites in the brain cause vasodilatation
CO2
What local metabolites in the muscle control auto regulation
Lactate, K+, H+, CO2
Most common cause of ASD
Osmium secundum defects
How are PFO and ASD different
In ASD the septa are missing rather than unfused
Heart defects associated with infants of diabetic mothers
Transposition of great vessels
Heart defect associated with Williams syndrome
Supravalvular aortic stenosis
Heart defects associated with 22q11 syndromes
Truncus arteriosus, tetralogy of Fallot
What causes the onion skinning in severe hypertension
Proliferation of smooth muscle cells
Most common presenting symptom of post-procedure atheroembolism
AKI
What is AAA associated with
Transmural inflammation
What is thoracic aortic aneurysm associated with
Cystic medial degeneration
What causes thoracic aortic aneurysm in syphillis
Obliterating endarteritis of the vasa vasorum
Triggers of Prinzmetal angina
Tobacco, cocaine, and triptans
Tx of Prinzmetal angina
Ca channel blockers, nitrates, and smoking cessation
Gross path of a heart after MI 4-24 hrs, 1-3 days, 3-14 days, and >2 weeks
4-24 hrs: dark mottling; pale with tetrazolium stain, 1-3 day: hyperemia , 3-14 days:hyperemia border, central yellow-brown softening, and >2 weeks: grey-white
What is the scar composed of after an MI
Type 1 collagen
What is Loffler syndrome?
Endomyocardi fibrosis with a prominent eosinophilia infiltrate, associated with restrictive/infiltration cardiomyopathy
Endocarditis is IV drug user
S. Aureus OR pseudomonas, Candida
Culture negative endocarditis
Coxiella brunette, Bartonella app. HACEK (Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella)
What is an Aschoff body?
Granuloma with giant cells
What is an Anitachkow cell
Enlarged macrophage with ovoid, waxy, rod-like nucleus. Associated with rheumatic fever
Tree bark appearance of the aorta
Tertiary syphillis
Txt of Raynaud phenomenon
Ca channel blockers
Which small vessel vasculitis does not have granulomas
Microscopic polyangiitis
Presentation of microscopic polyangiitis
Necrotizing vasculitis commonly involving lung, kidneys, and SKIN with pauci/immune glomeruli nephritis and palpable purpura. Similar to Wegners (granulomatosis with polyangiitis) but WITHOUT NASOPHARYNGEAL INVOLVEMENT
Presentation of eosinophilia granulomatosis with polyangiitis
Asthma, sinusitis, skin nodules or purpura, peripheral neuropathy
MOA of fenoldopam
Dopamine D1 receptor agonist- coronary, peripheral, renal, and splanchnic vasodilation. Decreases BP and increases natriuretic
