A 55-year-old man with a history of coronary artery disease and alcoholism presents to the emergency department complaining that he vomited bright red blood twice this morning. He denies previous episodes of bleeding or abdominal pain. On examination, he is a malnourished man in acute distress. His blood pressure is 90/50 mm Hg and his pulse is 110/min. His mucous membranes are dry and his sclera are icteric. Abdominal examination reveals a distended abdomen with an enlarged, palpable spleen. Purplish striae are seen around the umbilicus. On rectal examination, Iarge hemorrhoids are seen, but the stool is negative for blood.
Q 1
Which of the following is the most likely diagnosis?
/ A. Erosive gastritis
/ B. Esophageal varices
/ C. Infectious enteritis
/ D. Mallory Weiss tear
/ E. Peptic ulcer disease
Q 2
Which of the following coagulation factors would most likely be unaffected in this patient?
/ A. Factor ll
/ B. Factor VII
/ C. Factor IX
/ D. Factor XIII
/ E. Von Willebrand's factor
Q 3
Which of the following anatomic relationships provides the basis for the patient's hemorrhoids?
/ A. Coronary vein anastomosis with the esophageal plexus
/ B. Inferior rectal vein anastomosis with the iliac vein
/ C. Paraumbilical vein anastomosis with the inferior epigastric vein
/ D. Superior mesenteric vein anastomosis with the splenic vein
/ E. Superior rectal vein anastomosis with the inferior and middle rectal vein
Q 4
Which of the following structures are found in the portal triad?
/ A. Hepatic vein, common hepatic artery, common bile duct
/ B. Portal vein, celiac artery, common bile duct
/ C. Portal vein, common hepatic artery, common bile duct
/ D. Portal vein, falciform ligament, common bile duct
/ E. Portal vein, sinusoids, bile canaliculi
A1
The correct answer is B. While all of the answer choices listed must be considered in the differential, upper gastrointestinal bleeding from esophageal varices is most likely. This patient displays many of the stigmata of hepatic disease and portal hypertension: icteric sclera, hemorrhoids, distended umbilical veins (caput medusae), and a history of alcoholism. In this setting, esophageal varices would be the most likely. To make this diagnosis definitively, however, one needs to examine the gastrointestinal tract endoscopically.
Erosive gastritis (choice A) is a source of upper gastrointestinal hemorrhage, but it seldom bleeds so profusely that the patient becomes hemodynamically unstable.
Infectious disease in the gastrointestinal tract (choice C) may produce hemorrhage, but it tends to produce lower GI bleeding.
Mallory Weiss tears (choice D) produce upper GI bleeding. This tearing of the gastroesophageal junction occurs in alcoholics, but usually a history of retching precedes bleeding. No such history is elicited here.
Peptic ulcer disease (choice E) can produce brisk upper GI bleeding. It is less likely in this case because this patient has no history of GI pain.
A2
The correct answer is E. Von Willebrand's factor is a coagulation factor produced by the vascular endothelium and megakaryocytes. It is the only protein in the cascade that is not synthesized in the liver. vWF mediates the adhesion of platelets to the vessel wall basement membrane after vascular injury. Patients with a deficiency of von Willebrand's factor have a tendency to bleed. It is an autosomal dominant disease, and the ristocetin cofactor activity test is the best way to clinically assess vWF function.
Factor II (choice A) is produced in the liver. Deficiency is very rare, but can produce spontaneous or posttraumatic bleeding.
Factor VII (choice B) is produced in the liver.Severe factor VII deficiency is a very rare cause of bleeding.
Factor IX (choice C) is produced in the liver. A factor IX deficiency is known as hemophilia B, which is an X-linked disease.
Factor XIII (choice D) is produced in the liver. A deficiency of factor XIII produces delayed bleeding and poor wound healing.
A3
The correct answer is E. The patient's hemorrhoids are a consequence of his portal hypertension. The patient has a cirrhotic liver, which impedes circulation in the portal system. As the pressure rises in the portal system, blood in the portal circulation begins to backflow into the caval circulation. At the sites at which the portal system anastomoses with the caval circulation, venous engorgement occurs. At one such site, the confluence of the superior rectal vein (portal) with the middle and inferior rectal vein (caval), this venous engorgement leads to hemorrhoids.
The coronary vein anastomosis with the esophageal venous plexus (choice A) provides the anatomic basis for the esophageal varices seen in portal hypertension. As pressure builds in the portal system, venous engorgement occurs, and varices are produced in the distal esophagus. These varices can be the site of life-threatening upper GI bleeding.
The anastomosis of the inferior rectal vein with the iliac vein (choice B) is a caval-caval anastomosis and would not be affected by portal hypertension.
The anastomosis of the paraumbilical vein and the inferior epigastric vein (choice C) is the portal-caval anastomosis responsible for the purplish striae or caput medusae seen on this patient's abdomen. This circulatory route is an embryologic remnant, and is only patent when portal pressure rises high enough to re-open this pathway.
The anastomosis of the superior mesenteric vein and the splenic vein (choice D) marks the origin of the portal vein. It may have an elevated pressure, but it is not the basis for hemorrhoids.
A4
The correct answer is C. The portal triad contains the portal vein, common hepatic artery, and common bile duct. It is found in the fold of peritoneum, called the hepatoduodenal ligament, that separates the greater and lesser abdominal sacs.
None of the other choices offer a complete answer:
The hepatic vein (choice A) drains the liver into the inferior vena cava (IVC).
The celiac artery (choice B) supplies blood to the anatomic foregut. One of its branches, the common hepatic artery, travels in the porta hepatis.
The falciform ligament (choice D) is the remnant of the umbilical vein that passes from the anterior abdominal wall to the superior surface of the liver.
Bile canaliculi (choice E) are microscopic channels that drain bile from the hepatocytes.
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