1. Esophageal Dysfunction
Answer: 2. Pathophysiology of gastro-esophageal reflux. Manometric finding felt to be most responsible for reflux is transient relaxation of the LES. Answers 1 and 5 are findings seen in achalasia. Answers 3 and 4 are findings observed in esophageal spasm.
Answer: 4. Causes of reflux esophagitis. Most commonly due to acid reflux. Other answers are not likely based on the clinical history.
Answer: 3. Esophageal motility findings in scleroderma due to infiltration of esophagus with fibrosis.
2. Drugs in GI Diseases
Answer: 5 . Rabeprazole is a proton-pump inhibitor. The proton-pump inhibitors are most effective in prevented gastric complications from patients on NSAIDs.
Answer: 2. Cardiac arrhythmias are not a side effect of metoclopramide.
Answer: 3. Aluminum hydroxide is constipating. All the other drugs can cause diarrhea as a side effect.
3. Gastric and Duodenal Dysfunction
Answer 2. Duodenal ulcer with GI bleeding. Many duodenal ulcers are h.pylori associated. Duodenal ulcers are associated with above normal acid production. There is an increased sensitivity of parietal cells to gastrin in patients with peptic ulcer. High gastrin levels usually seen in Zollinger-Ellison syndrome and not benign peptic ulcer disease.
Answer: 4 . Effect of aspirin is the most important factor in ulcerogenesis in this situation. H.pylori is not as common a cause of gastric ulcers compared to duodenal ulcers. Gastric mucus is not affected in this situation. An exuberant blood supply is protective. High gastric acid production is not typically seen in NSAID induced ulcers.
Answer: 1. Positive H.pylori. The urea breath test is a non-invasive way of diagnosing h.pylori. H.pylori is associated with type B gastritis. Type A gastritis is autoimmune gastritis which is associated with pernicious anemia due to antibodies to parietal cells. A gastrin level greater than 1000 and ulcers in the 3rd and 4th portions of the duodenum are findings seen in the rare disorder, Zollinger-Ellison syndrome due to tumor (gastrinoma) secreting gastrin.
4. Pathophysiology of Diarrhea
Answer: 3. Case of lactose intolerance. Causes osmotic diarrhea. Fecal osmotic gap wide (usually greater than 125) due to relatively lower concentration of sodium and potassium in stool.
Answer: 5. Case of celiac sprue with dermatitis herpetiformis rash. Iron deficiency due to malabsorption of iron. Celiac disease is very common in individuals of Northern European descent.
Answer: 8. Zollinger-Ellison syndrome. Diarrhea is due to hypersecretion of HCl (increased fluid load to small intestine) and acid inactivation of pancreatic enzymes causing fat malabsorption.
5. Inflammatory Bowel Disease
Answer : 4 .
Answer: 2. Peripheral arthritis. The other complications are less likely to follow the course of the intestinal disease.
Answer: 4. Clinical description of case of ulcerative colitis (UC). P-ANCA is more commonly found in UC. The other answers are findings seen in Crohn’s disease.
6. Colon Disorders
Answer: 4. Narcotics, including morphine and its derivatives, are a well known cause of constipation. Irritable bowel syndrome would be very unlikely in a 75 year old. The clinical history does not suggest that any of the other answers would be possible.
Answer: 2. Internal hemorrhoids. All of the other answers would typically cause some degree of rectal/peri-anal pain. Internal hemorrhoids are painless.
Answer: 3. Diverticula are uncommon in the cecum, ascending colon, and transverse colon. The sigmoid colon is the most common area of the colon where one finds diverticula.
Answer: 3. Even in women during pregnancy where there is relative stasis of bile flow, cholesterol stones are most common. This is due to supersaturation of bile with cholesterol. The serum cholesterol level is not associated with the development of gallstones.
Answer: 5. Acute cholecystitis – inflammation/infection of the gallbladder. The ultrasound results are consistent with cholecystitis (thickened gallbladder wall).There are no blood tests provided that would suggest acute hepatitis or pancreatitis. Patients with a gallstone ileus have evidence of a bowel obstruction (nausea, vomiting, dilated bowel on x-rays). Acute cholangitis usually results in a dilated bile duct on ultrasound.
Answer: 4. Rapid weight loss. Sickle cell disease is a risk factor for pigment stones. The other answers are not risk factors for gallstones.
Answer: 3. Many patients with severe pancreatitis may develop hypocalcemia. The other blood tests are not as important as the calcium.
Answer: 2. Acute pancreatitis due to biliary sludge (early stones). Pancreatic enzymes are activated within the pancreas. There is no evidence of a pancreatic stricture. Proteinaceous plugs are part of the pathophysiology of chronic alcoholic pancreatitis.
Answer: 4. The serum amylase, calcium or B12 level do not help one diagnose chronic pancreatitis. The diagnosis is based on finding morphologic evidence of calcifications in the pancreas or pancreatic ductal abnormalities or evidence of depressed pancreatic function (secretin test). An abdominal CT scan may show calcifications in the pancreas or atrophy of the pancreas – findings consistent with chronic pancreatitis.
9. Viral hepatitis
Answer: 4. Case of acute hepatitis B due to marked elevations in liver blood tests. In acute hepatitis B the Hepatitis B core IgM antibody is always elevated. The hepatitis B surface antigen is also typically positive. The Hepatitis B e antigen is also often elevated as a marker of active viral replication.
Answer: 3. The blood supply has been screened for hepatitis since 1992. The likelihood of transmission by transfusion is low. The risk of acquiring Hepatitis C is more likely via IV drug use then sexual contact or nasal cocaine use. Hepatitis C is not transmitted by a fecal-oral route.
Answer: 1. In a vaccinated patient, the only positive serologic test should be the hepatitis B surface antibody.
10. Liver function Tests
Answer: 2. AST>ALT pattern typical of acute alcoholic hepatitis.
Answer: 8. Typical story for primary biliary cirrhosis. Patients with bile duct obstruction will often have elevations in the Total bilirubin, ALT, and AST.
Answer: 3. Given negative viral studies, acetaminophen overdose is most likely. Autoimmune hepatitis would be other possibility but this is more common in women.
11. Liver Failure: Cirrhosis
Answer: 2. Cirrhotic patients have a hyperdynamic cardiac response to low peripheral vascular resistance. Portal hypertension (present given history of esophageal varices) develops due to resistance to blood flow in the liver and a high rate of blood flow in the splanchnic circulation.
Answer: 1. Portal vein thrombosis is a cause of pre-hepatic portal hypertension. In this situation the hepatic vein pressure gradient is normal because the wedged and free hepatic vein pressures are normal.
Answer: 4. A wide (> 1.1.) serum-ascites albumin gradient correlates well with portal hypertension. Portal hypertension would most likely be found in advanced hepatitis C related cirrhosis. The other answers are causes of a narrow albumin gradient.