Gastrointestinal Flashcards
Most common asked or tested physiological changes as a result of cirrhosis with progressive liver fibrosis
- Formation of a high-resistance system (portal hypertension), results in the following:
- ⬆Nitrous oxide and vasodilatory factors (from bacterial products [endotoxin] accumulated due ⬇host defenses, ⬆portosystemic shunting➡⬇toxin clearance)
- Splanchnic vasodilation➡⬇systemic vascular resistance, compensatory ⬆HR, CO▶Hyperdinamic circulation
- (+) RAAS and ADH➡Na and H2O retention
Most specific and sensitive test to evaluate celiac disease
IgA anti-tissue transglutaminase (anti-tTG) and anti-endomysial antibodies (anti-EMA)►jejunal mucosal damage
*Serum antigliadin antibody no longer used routinely►lower sensitivity and specificity
How do you diagnose celiac disease without small bowel biopsy?
Positive serology (anti-tTG, anti-EMA) + confirmed dermatitis herpetiformis by Bx
*Small bowel biopsy is the most accurate test
Most accurate test of celiac disease and its common findings
Small bowel biopsy→blunting of distal duodenal and/or proximal jejunal villi, crypt hyperplasia, intraepithelial lymphocytosis
*Always necessary to exclude bowel wall lymphoma
How do you differentiate corticosteroid-induced vs statin-induced myopathy?
- Corticosteroid induced→muscle enzymes normal, EMG normal. Lower extremity weakness and proximal atrophy. No correlation with dosage or duration.
- Statin-induced→↑↑ CPK ten times upper limit, weakness
Enough findings to diagnose Wilson disease. Most accurate test to Dx.
- Low ceruloplasmin concentration (<20 mg/dL), Keyser-Fleischer rings on slit-lamp examination
- Liver Biopsy
How do you differentiate between Rotor vs Dubin-Johnson syndrome?
- Dubin-Johnson→lack elevation of urinary coproporphyrins, has darkly pigmented liver
- Rotor→milder in presentation without black liver, ↑urinary coproporphyrins
When do you evaluate for liver transplantation?
- Decompensated liver failure
- Portal hypertension
- ↓Synthetic function (variceal hemorrhage, ascites, encephalopathy)
*Liver biopsy→evaluate extent of structural damage to the liver and candidacy for liver transplantation
Esophagus manometry results in scleroderma. How do you suspect esophageal compromise?
- ↓Lower esophageal sphincter pressure, ↓esophageal peristalsis
- Gastroesophageal reflux disease (GERD) and dysphagia
What is motility-type dysphagia? Example of disease with that.
- Difficulty with liquids and solids from the onset of symptoms
- Diffuse esophageal spasm
Test to confirm lactose intolerance
Lactose hydrogen breath test➡⬆hydrogen levels after lactose ingestion (bacterial carbohydrate metabolism)
Gradual luminal narrowing of the esophagus after many years of gastroesophageal reflux disease (GERD).
Peptic esophageal stricture
Diagnostic test for gastrointestinal angiodysplasia
Mesenteric angiography▶Dilated, slow-flowing vein in the colon
Treatment for gastrointestinal angiodysplasia
Endoscopic ablation→cauterization or laser coagulation (if fails, surgical removal of affected bowel)
Most common cause of lower GI bleeding
- Diverticulosis
2. Angiodysplasia
How do you screen for factitious diarrhea due to laxative abuse?
Stool screen for diphenolic (eg, bisacodyl) or polyethlynele-containing laxatives
How do you confirm the diagnosis of factitious diarrhea due to laxative abuse?
Colonoscopy➡Melanosis colia▶dark brown discoloration of the colon with pale patches of lymph follicles (alligator skin)
Useful tests to rule out factitious diarrhea
- Stool osmolality: Normal➡290 mOsm/Kg (plasma). Hypoosmolality➡addition of water or other dilute fluid. Hyperosmolality➡addition of concentrated fluid )urine)
- Stool electrolytes: ⬆Mg and PO4▶overuse of saline osmotic laxatives
- Stool osmotic gap: Osmotic laxatives (lactulose, polyethyleneglycol)▶⬆osmotic gap diarrhea. Senna and bisacodyl▶⬇osmotic gap secretory diarrhea
Where is the most common location of the VIPoma? How do you confirm the diagnosis?
- Pancreatic tail
- VIP level >75 pg/mL
Most common electrolytic disturbances in VIPoma syndrome
- VIPoma syndrome (pancreatic cholera)►secretory, watery diarrhea and ↓ gastric acid secretion→hypokalemia and hypo or achlorhydria
Colonoscopy recommendations for colon cancer screening in inflammatory bowel disease
- 8-10 years after diagnosis (12-15 years if only left colon)
- Repeat every 1-3 years
Colonoscopy recommendation for colon cancer screening in lynch syndrome (HNPCC)
- Age 20-25 years
- Repeat every 1-2 years
Colonoscopy recommendations for colon cancer screening in classic familial adenomatous polyposis
- Age 10-12 years
- Repeat anually
Colonoscopy recommendations for colon cancer screening family history of adenomatous polyps or CRC
- Age 40 or 10 years before the age of diagnosis of the relative
- Repeat every 5 years
What is the long-term outcome of nonalcoholic fatty liver disease (NAFLD)?
- Hepatic Fibrosis 40%
- Cirrhosis 10-15%
Since hepatic steatosis is similar between NAFLD and alcoholic liver diseases, how can you differentiate both?
- NAFLD→AST/ALT ratio <1
- Alcoholic liver disease→AST/ALT ratio 2:1
*Off course ask for severe alcohol exposition
Best diagnostic test for esophageal perforation and expected finding
Esophagography or CT scan with water-soluble contrast (no barium, it is inflammatory)→Leak from perforation
Most probable diagnosis in a patient with chest/back pain, fever, vomiting and pleural effusion. Most common etiologies.
Esophageal perforation or rupture
- Effort rupture (ex, self-induced vomiting, Boerhaave syndrome)
- Instrumentation (ex, endoscopy), trauma
- Esophagitis (infection, pills, caustic)
Best diagnostic test for esophageal perforation and expected finding
Esophagography or CT scan with water-soluble contrast (no barium, it is inflammatory)→Leak from perforation
What you should rule out when you find liver decompensation (new-onset ascites, variceal bleeding) in a patient with alcohol-induced cirrhosis?
Thrombus or Hepatocellular carcinoma (HCC)➡clot or mass blocking portal or hepatic veins▶Abdominal ultrasound
*Patient with cirrhosis screening with abdominal ultrasound each 6 mo to evaluate new onset asymptomatic HCC
Clinical presentation of acute diverticulitis
- Left lower quadrant pain
- Nausea, vomiting
- Bladder symptoms (urgency, dysuria, frequency) or sterile pyuria (➕leukocyte esterase, ➖nitrites/bacterias)➡bladder irritation from bowel inflammation
- Changes bowel habits (diarrhea, constipation)
Primary prophylaxis to prevent bleeding from esophageal varicose veins
- Endoscopic variceal ligation (EVL)➡preferred for larger varicose veins
- Nonselective beta-blocker➡propranolol, nadolol
Best initial test and most accurate test for bloody diarrhea
- Best initial➡Stool lactoferrin
- Most accurate➡Stool culture
Best initial test and most accurate test for achalasia
- Best initial: Barium esophagram➡”Bird’s beak sign”
- Most accurate: Manometry➡Failure lower esophageal sphincter to relax (⬇Esophageal peristalsis, ⬆Lower esophageal sphincter tone)
Treatments options for achalasia
- Pneumatic dilation (perforation risk <3%)
- Myotomy (more effective but more dangerous)
- Botulinum toxin (effect wear off in 3-6 mo, reinjections)
Clinical presentation of esophageal spasm. Which are the two forms of them?
- Sudden onset of severe chest pain not related to exertion, can be precipitated by drinking cold liquids
- Diffuse esophageal spasm (DES) and Nutcracker esophagus
*Both forms clinically indistinguishable. Hard to differentiate at the beginning with coronary disease. EKG and stress test normal
Most accurate test for Diffuse esophageal spasm (DES) and Nutcracker esophagus
Manometry➡Different pattern of abnormal contraction
Treatment for esophageal spastic disorders
Calcium channel blockers and nitrates (similar Prinzmetal angina)
*PPIs can improve some cases
Important history clue and best initial test for eosinophilic esophagitis
- Asthma and allergic diseases
- Endoscopy➡Multiple concentric rings
Most accurate test for eosinophilic esophagitis
Biopsy➡Eosinophilic infiltration of esophageal mucosa
Best initial and most effective therapy for eosinophilic esophagitis
- PPIs and eliminate allergenic food
- Swallow steroid inhalers (topical effect of steroids)
Difference between Schatzki ring and Plummer-Vinson syndrome esophageal lesions
- Schatzki ring➡from acid reflux, associated with hiatal hernia. Scarring or tightening (also called peptic stricture) of the distal esophagus.
- Plummer-Vinson syndrome➡associated with iron deficiency anemia, rarely transforms into squamous cell cancer. More proximal.
Treatment of Schatzki ring and Plummer-Vinson syndrome esophageal lesions
- Schatzki ring➡pneumatic dilation in an endoscopic procedure
- Plummer-Vinson syndrome➡ iron replacement at first▶may lead to resolution of the lesion
Best diagnostic test for Zenker diverticulum
Barium studies
*Do not answer nasogastric tube placement or upper endoscopy➡dangerous, may cause perforation
Finding on the most accurate test for the scleroderma esophagus compromised
Manometry➡inability to close the lower esophageal sphincter▶⬇LES pressure
Most common cause of epigastric pain
Non-ulcer dyspepsia
Treatment for cannabinoid hyperemesis syndrome
- Hot shower or bath
- Antiemetics (ondansetron) or benzodiazepines (lorazepam)
Most common cause of peptic ulcer disease
- Helicobacter pylori
2. NSAIDs
Treatment for GERD for whose do not respond to the medical management
- Nissen fundoplication➡wrapping the stomach around the lower esophageal sphincter
- Endocinch➡suture around the LES
- Local heat or radiation of LES➡scarring
*About 5% of GERD patients do not respond to medical therapies
Indication for stress ulcer prophylaxis
- Mechanical ventilation
- Burns
- Head trauma
- Sepsis with coagulopathy
Most common cause of upper GI bleeding
Peptic ulcer disease
Clinical presentation of gastritis
- Bleeding without pain➡“coffee-ground” emesis, large hematemesis, melena, Heme (guaiac) positive stool
- Severe, erosive gastritis➡epigastric pain
- Nausea, vomiting
- Asymptomatic
What you must always rule out in a patient with a gastric ulcer?
Gastric cancer is present in 4% of those with GU but in none of those with DU
Best next step when you suspect persistent helicobacter pylori infection with a duodenal ulcer and gastric ulcer
- DU: Think antibiotic resistance➡urea breath testing, stool antigen detection, or a repeat endoscopy for biopsy➡if ➕➡switching to metronidazole + tetracycline + PPIs + bismuth
- GU: repeat endoscopy to exclude cancer
What is Non-ulcer dyspepsia?
Epigastric pain with a normal endoscopy
Clues on clinical presentation that makes you suspect gastrinoma
Peptic ulcer disease symptoms + diarrhea (acid inactivates lipase)
How are the ulcers from gastrinoma?
- Large (>1–2 cm)
- Recurrent after Helicobacter eradication
- Distal in the duodenum
- Multiple
How do you confirm gastrinoma (Zollinger-Ellison syndrome)?
Any of them:
- ⬆Gastrin off antisecretory therapy (PPIs or H2 blockers) with high gastric acidity
- ⬆Gastrin despite a high gastric acid output
- Persistent ⬆Gastrin despite injecting secretin
What is the most accurate test to identify metastases from gastrinoma?
Somatostatin receptor scintigraphy (nuclear octreotide scan) + endoscopic ultrasound
(Always do first CT and MRI)
*Gastrinoma is associated with a massive increase in the number of somatostatin receptors in the abdomen
Best initial treatment for diabetic gastroparesis
Dietary modifications➡Blenderize foods, Restore fluids, Correct potassium and glucose levels
*Not always have to confirm diagnose to start treatment
Most accurate test to confirm diabetic gastroparesis
Nuclear gastric emptying study➡Bolus of food tagged with technetium▶delay in the emptying of food
Best initial test for diabetic gastroparesis
Upper endoscopy or abdominal CT scan➡ excludes luminal gastric mass or abdominal mass compressing the stomach
Which treatments can you give if the best initial therapy for diabetic gastroparesis fails?
- Metoclopramide➡⬆gastrointestinal motility (Do not use permanently: Dystonia and hyperprolactinemia)
- Erythromycin + antiemetics➡⬆gastrointestinal motility
- Gastric electrical stimulation (gastric pacemaker)
Most common cause of lower GI bleeding
Diverticulosis
What is the most important next step in the management of GI bleeding?
Fluid replacement with high volumes (normal saline or Ringer lactate)
Initial medical treatment for esophageal and gastric varices
Octreotide (somatostatin)➡⬇portal pressure
Best initial therapy for clostridium difficile colitis. Next best step if there is NO RESPONSE and if there is RECURRENCE.
- Oral Vancomycin
- NO RESPONSE➡Fidaxomicin
- RECURRENCE (there was resolution)➡tapered dose of vancomycin (another course) or fidaxomicin
What is fulminant clostridium difficile infection? Treatment.
- ⬆WBC, Metabolic acidosis, ⬆lactate, ⬆creatinine
- Vancomycin and metronidazole
Most accurate test for chronic pancreatitis
Secretin stimulation testing
Sensible and specific finding on imaging in chronic pancreatitis
- Abdominal x-ray➡calcification of the pancreas
- Abdominal CT scan➡pancreatic calcification (80% to 90% sensitive)
Most sensitive predictor of anastomotic leak after bariatric surgery (Roux-en-Y gastric bypass). What other manifestations you may find?
- HR>120/min most sensitive predictor
- Fever, abdominal pain, tachypnea
Why do patients with fat malabsorption (Ex, Chron disease, small intestinal disease) have a high risk of nephrolithiasis?
Hyperoxaluria
- Normally Calcium binds Oxalate in gut➡❌Oxalate absorption
- Fat malabsorption➡Calcium is bound by fat➡Oxalate is absorbed; ❌absorb bile salts➡⬇bile salts reabsorption in small intestine➡⬆⬆bile salts damage colonic mucosa➡⬆Oxalate absorption
Serologic testing to differentiate Crohn disease from Ulcerative colitis
- CD➡ANCA➖, Anti-Saccharomyces cerevisiae antibody (ASCA)➕
- UC➡ANCA➕, ASCA➖
Which procedure you must avoid in a patient with diverticulitis and why?
Colonoscopy➡infection weakens the colonic wall➡risk of perforation
Best test for diverticulitis
CT scan
Worst prognosis marker in acute pancreatitis
Low calcium
When you must rule out infection in pancreatitis? How do you do it?
- Severe necrosis➡>30% necrosis on CT or MRI
- Needle biopsy➡only way to confirm infection
Best initial and confirmatory test for spontaneous bacterial peritonitis
Ascitic fluid study➡Total leukocyte>1000, Neutrophils >250▶confirm diagnosis
*Culture is variable positive and gram stain has low sensitivity
Which symptom is very important to ask for when suspect hepatopulmonary syndrome?
Orthodeoxia➡hypoxia upon sitting upright
Most accurate blood test for primary biliary cholangitis
Antimitochondrial antibody
From the patient history, how you may distinguish primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC)?
80% of PSC occurs in association with IBD
Which test may help you distinguish PBC and PSC?
- PBC➡antimitochondrial antibody and liver biopsy (most accurate)
- PSC➡MRCP or ERCP▶beading, narrowing, strictures in biliary system (most accurate). Bx is not essential for Dx. (ONLY cause of cirrhosis for which Bx is the not most the accurate)
Findings in the iron studies profile on hemochromatosis
⬆serum Iron, ⬆Ferritin, ⬇Iron binding capacity
*Best initial test for hemochromatosis
Besides the liver biopsy, which studies are enough to confirm hemochromatosis?
MRI➡⬆iron deposition in the liver
➕
Hemochromatosis gene (HFE; mutation C282y) testing
Hemochromatosis treatment
Phlebotomy
How is the clinical presentation of Wilson disease in other organs than the liver compromise?
- CNS➡Psychosis, tremor, dysarthria, ataxia, seizures
- RBCs➡Coombs negative hemolytic anemia
- Kidneys➡Renal tubular acidosis, nephrolithiasis
Best initial test and most accurate test for Wilson disease
- Best initial➡Slit-lamp examination▶Kayser-Fleischer rings
- Most accurate➡abnormally ⬆copper excretion into urine after giving penicillamine
- ⬇Ceruplasmin is NOT the most accurate
- Liver Bx is sensitive and specific
Key findings on imaging and serum when suspect autoimmune pancreatitis
- CT scan➡enlarged, “sausage-shaped” pancreas
- ⬆serum IgG4 (IgG4-related pancreatitis), ➕ANA and rheumatoid factor
*Associated with Sjögren syndrome, autoimmune thyroiditis, interstitial nephritis, sclerosing cholangitis
Treatment options for Wilson disease
- Penicillamine➡chelate copper, removes it from body
- Zinc➡❌intestinal copper absorption
- Trientine➡copper-chelating
*Penicillamine cannot be used with allergy to penicillin➡zinc or trientine.
How do you assess for severe exocrine pancreas insufficiency? For which diagnosis is it useful?
- ⬇Fecal elastase
- ⬇serum Trypsinogen
- Chronic pancreatitis
Which findings on feces you may find high on inflammatory bowel disease?
⬆️Calprotectin or Lactoferrin
⬆️Fecal leukocytes
In a patient with liver disease, what is the indication to receive prophylaxis for SBP?
Cirrhosis with ascites + variceal bleeding
Classic clinical presentation of pellagra and its cause
- Niacin deficiency
- Clinical presentation, “3 Ds”:
- Dermatitis - sun-exposed areas, rough, hyperpigmented, scaly
- Diarrhea - watery, loss appetite, nausea, abd pain
- Dementia - memory loss, affective symptoms (depression), psychosis
Why you may have niacin deficiency? Which is the disease?
Pellagra
- Diet based on corn products (developing countries)
- Impaired nutritional intake (developed countries; alcoholics, chronic illness)
- Carcinoid syndrome➡⬇tryptophan
- Hartnup disease➡❌tryptophan absorption
- Prolonged Isoniazid therapy➡❌tryptophan metabolism
Most appropriate initial step and mainstay of treatment in a patient with MALT
Antibiotic eradication of Helicobacter pylori
*Majority of patients have complete recovery after Tx
Common trigger of GI bleeding in a patient with angiodysplasia
Aortic stenosis➡destruction of vWF multimers when pass through damage valve
What may suggest nocturnal diarrhea?
Secretory diarrhea
*Chronic infection, microscopic colitis, bile salt diarrhea, hormone-secreting tumor (gastrinoma, VIPoma)
Most common inciting factors of hepatorenal syndrome
- Spontaneous bacterial peritonitis
- Gastrointestinal bleeding
Characteristic rectal findings on colonoscopy of chronic radiation proctitis
- Multiple telangiectasiaa
- Mucosal pallor and friability
*Submucosal fibrosis and obliterative endarteritis➡tissue hypoxia▶neovascularization➡telangiectasias➡significant hematochezia
Imaging findings of hydatid cyst
Eggshell calcification of a hepatic cyst (CT scan)
*Echinococcus granulosus➡unilocular cystic lesions in any organ (liver, lung, bone, muscle); Echinococcus multilocularis➡multiple lesions
A 57-year-old man with colonoscopy 5 years ago showed a tubular adenoma, with the rest of the cardiovascular risk factors under control. Most appropriate next step.
Colonoscopy
- Low-risk polyps: 1 or 2 small tubular adenomas➡screening every 5 to 10 years
- Multiple polyps: >3, atypical features or large, serrated polyps➡screening every 3 years
