Gastrointestinal Flashcards
What causes NASH and NAFLD?
Peripheral insulin resistance leads to increased lipolysis, triglyceride synthesis and hepatic uptake of fatty acids. These free fatty acids increase oxidative stress and pro-inflammatory cytokines.
What GERD patients get immediate endoscopy?
Those with alarm symptoms: dysphagia, odynophagia, weight loss, anemia, GI bleeding, vomiting and men over 50 with symptoms > 5 years with cancer risk factors (tobacco & alcohol).
Natural history of acute pancreatitis
Mild symptoms with recovery in 3-5 days
What conditions can be responsible for acute liver failure demonstrated by AST/ALT > 10x normal.
Viral, alcoholic and autoimmune hepatitis. Ischemia. Malignancy. Wilson’s disease.
1st line treatment for patients with small non-bleeding esophageal varices
Non-selective beta-blockers (nadolol and propranolol) cause unopposed alpha-adrenergic-mediated mesenteric vasoconstriction and decreased portal flow.
If the patient has contraindications to beta-blockers you can do endoscopic banding.
Achalasia workup
1) Barium swallow 2) Manometry 3) Endoscopy to rule out malignancy at GE junction
Antimitochondrial antibody
PBC
Primary medication used in patients with PBC
Ursodeoxycholic acid is a hydrophilic bile acid that prevents biliary tree damage by more hydrophobic bile acids.
Source of GI bleeding if it raises the patients BUN:Cr?
Upper GI, this gives time to reabsorb the BUN created from Hgb breakdown in addition to BUN reabsorbed at the proximal tubule due to hypovolemia.
Melanosis coli
Dark brown discoloration of the colon with lymphoid follicles shining through indicative of abuse of anthraquinone-containing laxatives like bisacodyl.
How do diagnose someone with a gastrinoma
Serum gastrin level > 1000
Failure to suppress gastrin levels on secretin stimulation test
What patients get empiric oral metronidazole and what patients get empiric oral vancomycin for presumed C. diff colitis while awaiting stool toxin analysis? Who gets fidaxomicin?
Metronidazole = WBC 15k, sCr ≥ 1.5x baseline, serum albumin
Who gets pRBC transfusions?
No comorbidities and Hgb
What does cryoprecipitate consist of?
Factor VIII, factor XIII, vWF and fibrinogen
Who gets platelet transfusions?
Increased hemorrhage risk and
Evaluation of peritoneal tap for ascites
SAAG: peritoneal albumin - serum albumin
≥1.1 = portal hypertension (ascites, cirrhosis, Budd-Chiari)
How do you manage hepatic encephalopathy?
Treat precipitating cause
Ensure adequate nutrition without protein restriction
Prompt correction of hypokalemia or metabolic alkalosis as these promote conversion of ammonium to ammonia
Lower serum ammonia with lactulose followed by rifamixin if needed
1st line drug for patients with corkscrew esophagus
CCBs are 1st line for diffuse esophageal spasm
Complications associated with PBC
Severe hyperlipidemia Metabolic bone disease leading to osteoporosis Malabsorption Cirrhosis Hepatobiliary malignancy
Solid liver lesion with evidence of arterial flow and a central scar
Focal nodular hyperplasia
PSC
Associated with UC, p-ANCA, string of pearls on imaging and onion-skinning on path.
Germline mutations that increase the risk for pancreatic cancer
BRCA 1/2 and Peutz-Jehgers syndrome
Colonic polyp size that is particularly concerning for malignancy
> 2.5 cm
Treatment of duodenal ulcers due to H. pylori infection
Omeprazole + Clarithromycin + Amoxicillin
Most common causes of duodenal ulcers
NSAIDs and H. pylori
Diagnosis of lactose intolerance
Lactose H+ breath test, with a rise in H+ after lactose consumption secondary to bacterial metabolism in the gut.
Calculate the osmotic gap for stool
290 - [2 (stool Na + stool K)]. The gap is > 50 in all forms of osmotic diarrhea (lactose intolerance)
Best initial test for a patient presenting with a concerning, palpable lymph node and history of tobacco/alcohol use.
Panendoscopy to find the primary tumor source (esophagoscopy, laryngoscopy, bronchoscopy)
Drugs that can cause acute pancreatitis
Didanosine, azathioprine and valproic acid
Infections that can cause acute pancreatitis
CMV, legionella, aspergillus
Diagnostic criteria for acute pancreatitis
At least two of the following
- Acute epigastric pain +/- radiation to back
- Amylase/lipase > 3x normal limit
- Focal or diffuse pancreatic enlargement on contrast-enhanced CT
If ALT > 150, likely biliary etiology, check u/s
Gold standard for diagnosing small intestine bacterial overgrowth
Endoscopy with jejunal aspirate showing > 10^5 organisms
Charcot’s triad? Reynold’s pentad?
Fever, jaundice and RUQ pain. Add confusion + hypotension and it’s Reynolds pentad.
Colorectal cancer surveillance for patients with ulcerative colitis.
Start 8-10 years after initial diagnosis.
Other inflammatory condition associated with primary sclerosing cholangitis
UC
Patients who are at higher risk for angiodysplasia
Advanced renal disease, von Willebrand disease and in patients with aortic stenosis.
Stool color in patients bleeding from angiodysplasia
Maroon, this is because it is typically venous blood.
Significance of a low stool elastase
Chronic pancreatitis
What patients with BRBPR can undergo office anoscopy alone
Mineral deficiency that causes alopecia, abnormal taste, impaired wound healthing and pustular lesions around body orifices and on the extremities
Zinc
Mineral deficiency that can result in cardiomyopathy, especially in patients on chronic TPN
Selenium
How does lactulose work to decrease neurologic symptoms in patients with hepatic encephalopathy?
Colonic bacteria metabolize it to short-chain fatty acids, which acidifies the colon. Absorbable NH3 picks up an H+ and becomes non-absorbable NH4.
Medications that can cause esophagitis
Tetracyclines, potassium chloride, NSAIDs and bisphosphonates.
Screening recommendations for colorectal cancer
> 50 years: colonoscopy q10 years, annual FOBT or flex sig q5 years + FOBT q3 years.
Patients with FHx of CRC should be screened at age 40 or 10 years before first-degree relative was diagnosed.
Incubation periods of hepatitis A, B and C?
A = 30 days B = 30-180 days C = 40-50 days
ROME III criteria for IBS
3 days of discomfort per month for the past 3 months with 2 of the following:
Change in frequency, change in form and improvement with defecation.
When to drain a pancreatic pseudocyst
> 6 weeks, >6cm or secondarily infected
Most common cause of bile ductopenia in adults
PBC
In addition to nutritional deficiency, in what other conditions might you see pellagra.
Carcinoid syndrome (tryptophan depletion) and Hartnup disease (congenital disorder of tryptophan absorption)
Cause of the black liver in patients with Dubin-Johnson syndrome
Epinephrine metabolites in the lysosomes accumulate
How to diagnose Dubin-Johnson syndrome
Conjugated hyperbilirubinemia > 50%, normal LFTs and unusually high urinary levels of coproporphyrin I.
Liver enzyme that is less specific for hepatocellular damage
AST, it is also highly active in renal tissue, cardiac and skeletal muscle.
Complications of acute pancreatitis
Pleural effusion, ARDS, ileus and renal failure.
Preferred imaging modality for diagnosis of pancreatic cancer?
Head of pancreas: ultrasound
Body and tail of pancreas: CT with contrast
Diagnostic criteria for toxic megacolon
Radiographic evidence of > 6cm colonic dilation + at least 3 of the following:
- Fever > 38C
- HR > 120
- WBC > 10,500
- Anemia
Plus at least 1 of the following
- Volume depletion
- Altered sensorium
- Electrolyte disturbances
- Hypotension
Stepwise approach for treating patients with ascites
1) Na and H2O restriction
2) Spironolactone
3) Loop diuretic, don’t take off >1L/day
4) Abdominal paracentesis of 2-4L/day
Treatment of recurring hepatic hydrothorax due to portal hypertension
1) Therapeutic thoracentesis + salt restriction + diuretics
2) TIPS if this fails
Treatment recommended for patients with Wilson’s disease
Since they do not make enough ceruloplasmin to chelate copper and ship it out in the biliary tree, you must give them chelators like d-penicillamine or trientene.
Medications associated with pancreatitis
- Diuretics (furosemide and thiazides)
- IBD drugs (sulfasalazine, 5-ASA)
- Immunosuppressants (azathioprine)
- HIV medications (didanosine, pentamidine)
- Antibiotics (metronidazole and tetracycline)
Extra-hepatic manifestations of HCV
Porphyria cutanea tarda, lichen planus, leukocytoclastic vasculitis and essential mixed cryoglobulinemia.
When is GERD associated with gastric adenocarcinoma?
After > 20 years of symptoms
Infant with indirect hyperbilirubinemia > 25 that is unchanged with IV phenobarbital. Treatment?
Crigler-Najjar type I. Treat with phototherapy, plasmapheresis and eventual liver transplantation.
Infant with indirect hyperbilirubinemia
Crigler-Najjar type II. Treatment is usually unnecessary and you can give phenobarbital or clofibrate if bili gets too high.
Most common causes of cirrhosis in the US
EtOH and HCV
Treatment for patients with esophageal bleeding due to Mallory-Weis tear?
90% stop bleeding spontaneously. Do endoscopic sclerotherapy or banding if bleeding persists.
Drugs that increase serum levels of digoxin
Amiodarone, verapamil, quinidine and propafenone
Vaccines a patient should receive after diagnosis of HCV
HAV and HBV
Precipitants of hepatic encephalopathy
Sedatives, narcotics, hypovolemia, excessive nitrogen load, hypokalemia + metabolic alkalosis, hypoxia + hypoglycemia, infection and portosystemic shunts.
Most appropriate labs to order in a patient with suspect acute HBV infections
HBsAg and Anti-HBc IgM. There may be a window period where HBsAg has disappeared and Anti-HBs IgM appears. During this time only anti-HBc IgM will be positive.
Use of D-xylose absorption test
It is absorbed in the proximal small intestine regardless of pancreatic or brush border enzyme function. Abscence of D-xylose in the urine indicates malabsorption due to mucosal disease like Celiac’s.
Categories of drug-induced liver injury
1) Cholestasis: chlorpromazine, nitrofurantoin, erythromycin and anabolic steroids.
2) Fatty liver: tetracyclines, valproic acid and anti-retroviral drugs
3) Hepatitis: halothane, phenytoin, isoniazid and alpha-methyldopa
4) Toxic: CCl4, acetaminphen, tetracyclines, mushrooms
5) Granulomatous: allopurinol
Idiosyncratic drug-induced liver injury
Liver damage from taking the medication is irrelevant of the dose. This happens with isoniazid, chlorpromazine, halothane and antiretroviral therapy.
Why do patients with ZE syndrome get greasy, floating stools?
The excess acid degrades pancreatic lipase and fat malabsorption ensues.
Risks for development of C. difficile colitis
Advanced age
Clinda, beta-lactams, fluoroquinolones
Hospitalization
Comorbid illness
Prolonged PPI and H2-blocker use
Management of a patient with toxic megacolon
Prompt IV steroids (especially if due to IBD)
NG decompression
IV fluids
Antibiotics
Emergent subtotal colectomy with end-ileostomy if medical therapy fails
Definition of hepatorenal syndrome
Decreased GFR in the absence of shock, proteinuria or other clear cause of renal dysfunction that fails to respond to 1.5L NS bolus.
Type 1: rapidly progressive, patients die within 10 weeks
Type 2: slowly progressive, patients die within 3-6 months
Criteria for diagnosing Lynch syndrome (Amerstam I criteria)
3+ relatives with CRC, 1 must be a first-degree relative of the other 2.
Involvement of 2+ generations
1 case diagnosed before age 50
FAP has been excluded
How to distinguish biliary colic from cholecystitis
Biliary colic pain resolves in 4-6 hours and there is no abdominal tenderness, fever or leukocytosis.
