Case Study 5 in Order
One of your patients has a gallstone that is completely blocking the duct that drains the liver, the gall bladder, and the pancreas. The gallstone is blocking the entrance to the duodenum - near the Sphincter of Oddi - after the point where the common bile duct and the pancreatic duct merge (it's called the "hepatopancreatic ampulla"), therefore, bile and pancreatic secretions are not reaching the lumen of the small intestine. If the gallstone in this patient completely blocks the hepatopancreatic ampulla so no bile is reaching the small intestine should you expect the patient's stools to be the normal brown color or clay (or whitish) colored? A) normal brown B) clay or whitish
clay or whitish In this case there is a total blockage of bile secretion into the small intestine due to complete blockage of the hepatopancreatic ampulla. "Blockage of bile secretion into the duodenum means bilirubin (a component of bile) is not secreted into the GI tract for bacteria to act on (bacterial action on bilirubin produces the brown color of feces). Without bilirubin, feces are greyish white (lighter than normal)."
Cecile's parents notice that she is not gaining weight like other children her age. They ask you if this problem could be due to her cystic fibrosis. They want to know how her cystic fibrosis would cause the inability to gain weight.
If food in the small intestine is not digested, it is not absorbed into the blood and is not available to cells for their use for energy or for anabolism (for synthesis reactions and growth). In Cecile, digestive enzymes from the pancreas are not reaching the small intestine due to obstruction of the pancreatic duct. If food in the small intestine is not digested, it is not absorbed into the blood and is not available to cells for their use for energy or for anabolism (for synthesis reactions and growth). This undigested food stays in the GI tract (which is the reason for the "fatty stools" or steatorrhea in a previous question). Even though she is eating, her cells are not getting what they need to be a healthy, growing child.
Explain the events that would cause autodigestion of the pancreas and pancreatitis. That is, think about what enzyme would start the process of autodigestion. That is, what enzyme activates the other enzymes?
Trypsin would need to be activated to activate the other protein digesting enzymes. The protein digesting enzymes would then cause digestion of pancreatic tissue - this believed to be what occurs in autodigestion of the pancreas with pancreatitis (that is, trypsin somehow gets activated - perhaps by lysosomal enzymes - and then trypsin activates the other enzymes).
Cecile is begging for a popsicle that her mother made with Kool aide and table sugar (sucrose). Should Cecile be able to digest the sucrose in the popsicle? Another way to say it would be should she be able to enzymatically break down the disaccharide sucrose? a) no (due to her pancreatic duct obstruction) b) yes
Yes Cecile should be able to digest the sucrose in the popsicle. The popsicle Cecile ate was homemade with table sugar or sucrose (since store-bought popsicles could be made of other ingredients). Sucrase is a disaccharidase on the brush border of the small intestine, so Cecile's pancreatic duct blockage does not prevent breakdown of sucrose.
Olive is a 68 year old homeless woman who lives on the streets of your large city. She has often come to the emergency room for treatment of many ailments. As an emergency room physician you have seen Olive many times over decades and each time you have seen her you noticed she had been heavily drinking alcohol. She now has been diagnosed with cirrhosis of the liver (a disease of the liver in which liver tissue is replaced by fibrous tissue and the liver is unable to perform its normal functions). Olive has developed jaundice. Years have passed and Olive is still drinking excessive alcohol and is now in liver failure, that is, her liver is failing as an organ (she has lost 80-90% of liver function). If Olive's liver is unable to perform normal functions, all of the following would likely be decreased EXCEPT A) bile salt production B) amount of undigested fat in the GI tract C) blood clotting D) albumin concentration in blood plasma E) osmotic pressure of blood plasma
amount of undigested fat in the GI tract If Olive's liver is unable to perform normal functions, all of the following would likely be decreased EXCEPT amount of undigested fat in the GI tract. The liver produces bile salts. With severely decreased liver function in liver failure, bile salt production (and secretion) would decrease. With less bile salts in the small intestine there would be less emulsification of fat and less digestion of fat; there would be also be less absorption of fat due to decreased digestion and decreased micelle formation (since bile salts are needed for micelle formation). This would mean less digestion and absorption of fat and therefore fat would remain in the GI tract and cause fatty or oily stools, which is called steatorrhea. Steatorrhea occurs in liver failure. On page 221 of the Course Pack you see that fibrinogen is made by the liver. With decreased liver function and decreased fibrinogen synthesis you should expect decreased clotting. (Note: There are also other clotting proteins made by the liver you that may have learned about in other classes, however, you can answer the question just based on a decrease in fibrinogen production.) Also you learn in Digestive Physiology that vitamin K is called "the blood clotting vitamin". Vitamin K is a fat soluble vitamin and would be low in a patient with liver failure because they would have decrease absorption of this vitamin due to decreased production of bile salts. A vitamin K deficiency would decrease blood clotting. On page 221 of the Course Pack you also see that albumin is made by the liver and that albumin is important for the osmotic pressure of plasma. With severely decreased liver function in liver failure 9 you should expect decreased albumin concentration in the blood and decreased osmotic pressure of the plasma (which causes edema). Out of all the choices, the only one that is NOT decreased is the amount of undigested fat in the GI tract. Notice that steatorrhea occurs in liver failure and in cystic fibrosis.
You have a patient who has had surgical removal of their entire stomach (total gastrectomy) because of cancer. Though it would have been preferable to leave at least part of the stomach in the patient (as usually occurs) it was not possible in this patient due to the cancer. Somehow a mistake was made and the patient did not receive proper instructions after their surgery and the patient just ate a large meal. Due to the large meal in this patient without a stomach, the fluid inside the duodenum will have an osmolarity higher than normal or hypertonicity in the duodenum will occur. Due to the conditions in the duodenum described above, a(n) ____________ in blood volume can occur and cause circulatory problems in this patient. A) increase B) decrease
decrease Due to the conditions in the duodenum described above, a(n) decrease in blood volume can occur and cause circulatory problems in this patient. The lumen of the duodenum would become hypertonic. This would cause movement of fluid from the blood, would decrease blood volume, and could cause circulatory problems (see page 490 of Course Pack). Also, the small intestine would be distended, which can cause vomiting. The collection of symptoms that occur when a large amount of food enters the small intestine is called "dumping syndrome".
As a knowledgeable physician you _______ prescribe oral enteric coated enzymes for Cecile. (Enteric coated means that the drug will dissolve in the small intestine, not in the stomach. It has a special coating which protects it from stomach acid.) a) do b) do not
do As a knowledgeable physician you do prescribe oral enteric coated enzymes for Cecile. You should prescribe the type of enzymes that are produced in the pancreas but are not able to reach the duodenum in Cecile due to the pancreatic duct blockage. Most patients (some sources state 90%) with cystic fibrosis are treated with pancreatic enzyme replacement, that is, they take oral (by mouth) pancreatic enzymes. The enzymes include lipase, amylase, and protein digesting enzymes. Protecting the enzymes taken orally from stomach acid and allowing the drug to dissolve in the duodenum makes sense - stomach acid could alter the protein enzymes' shape and function and pepsin might digest the enzymes. The protective coating would allow functional enzymes to make it into the small intestine.
Due to the pancreatic duct obstruction, Cecile would have decreased (or lower than normal) secretion of bile into the duodenum a) true b) false
false The question asks whether pancreatic duct obstruction causes decreased secretion of bile into the duodenum. The answer is false because obstruction of the pancreatic duct (by itself, that is, no other duct obstructed) does not block bile secretion into the duodenum. Bile duct obstruction and decreased secretion of bile into the duodenum CAN OCCUR in cystic fibrosis. That is, the bile duct is another duct in the body that can become obstructed.
Olive is a 68 year old homeless woman who lives on the streets of your large city. She has often come to the emergency room for treatment of many ailments. As an emergency room physician you have seen Olive many times over decades and each time you have seen her you noticed she had been heavily drinking alcohol. She now has been diagnosed with cirrhosis of the liver (a disease of the liver in which liver tissue is replaced by fibrous tissue and the liver is unable to perform its normal functions). Olive has developed jaundice. What kind of jaundice does Olive have?
hepatic jaundice Hepatic jaundice occurs when the liver is diseased and cannot deal with even the normal load of bilirubin. If the liver cannot secrete bilirubin into the bile then it will accumulate in the blood and cause jaundice.
You have a patient who has had surgical removal of their entire stomach (total gastrectomy) because of cancer. Though it would have been preferable to leave at least part of the stomach in the patient (as usually occurs) it was not possible in this patient due to the cancer. Somehow a mistake was made and the patient did not receive proper instructions after their surgery and the patient just ate a large meal. Due to the large meal in this patient without a stomach, the fluid inside the duodenum will have an osmolarity ___________ than normal or _____________________in the duodenum will occur. (Hint: hypotonicity means hypotonic fluid and hypertonicity means hypertonic fluid) A) lower, hypotonicity B) higher, hypertonicity
higher, hypertonicity Due to the large meal in this patient without a stomach, the fluid inside the duodenum will have an osmolarity higher than normal or hypertonicity in the duodenum will occur. Think about the storage function of the stomach and that normally, the stomach is emptied at a rate that is optimum for the digestion and absorption of food. Normally, the duodenum (through neural reflexes and enterogastrones) can inhibit the stomach's motility and decrease stomach emptying when distension of the duodenum increases or fats, osmolarity, or acid in the duodenum increases. So the food the duodenum is not "ready for" is stored in the stomach until the duodenum can "deal with it". What this patient (without a stomach) eats goes directly into the duodenum all at once. The reason that the patient (who had their stomach removed) should eat many small meals rather than one, two, or three relatively large meals a day is that the entire meal will enter the duodenum all at once. Let's say that a large meal entered the patient's duodenum. As the food begins to be digested, one food molecule becomes many (maybe hundreds) of osmotically active particles. The lumen of the duodenum would become hypertonic.
Cecile's parents ask you if blockage of the pancreatic duct could cause more problems than just pancreatic enzymes not reaching the duodenum. They describe to you that they read that blockage of the pancreatic duct can cause "autodigestion" of the pancreatic tissue and pancreatitis. They read that pancreatitis can occur in cystic fibrosis. They ask you how autodigestion of the pancreas could happen. You reply that normally what happens is that pancreatic protein digesting enzymes are secreted in an _______________ form into the small intestine. In pancreatitis, the enzymes are _____________ while still in the pancreas which causes irritation of the tissue and inflammation. a) active, inactive b) inactive, active
inactive, active You reply that normally what happens is that pancreatic protein digesting enzymes are secreted in an _______________ form into the small intestine. In pancreatitis, the enzymes are _____________ while still in the pancreas which causes irritation of the tissue and inflammation. Protein digesting enzymes are secreted in an inactive form to protect the secreting cells from self-digestion. You only need to know that part of the question for the answer, which leads you to what happens in pancreatitis in which the enzymes become activated while still in the pancreas.
Cecile's parents are worried that she may develop diabetes mellitus. They think that the pathophysiological events possible in her pancreas could cause the disease diabetes mellitus. You correctly respond that diabetes mellitus _____ possible due to pancreatitis. A) is B) is not is You correctly respond that diabetes mellitus is possible due to pancreatitis. If autodigestion of the pancreas due to pancreatitis damages the pancreatic beta cells (that is, the cells that secrete insulin), then Cecile could develop diabetes mellitus. Also what can be occurring is fibrosis of the pancreas could be causing damage of the pancreatic beta cells. Cystic fibrosis patients often do develop diabetes mellitus.
is You correctly respond that diabetes mellitus is possible due to pancreatitis. If autodigestion of the pancreas due to pancreatitis damages the pancreatic beta cells (that is, the cells that secrete insulin), then Cecile could develop diabetes mellitus. Also what can be occurring is fibrosis of the pancreas could be causing damage of the pancreatic beta cells. Cystic fibrosis patients often do develop diabetes mellitus.
A gallstone is blocking the common bile duct in your patient. You know that the common bile duct is formed when the duct from the liver (the hepatic duct) merges with the duct from the gall bladder (the cystic duct). The blockage of the common bile duct in your patient causes a decrease in bile reaching the lumen of the small intestine compared to a normal person. In this patient no other duct is blocked, that is, the gallstone is not blocking or preventing secretions from the pancreas from reaching the duodenum. The patient with the gallstone blocking the common bile duct has developed jaundice - yellowing of the eyes and skin due to excessive bile pigments in blood. Which kind of jaundice would be occurring in this patient with common bile duct blockage? ______________ Imagine another patient with hemolytic jaundice due to an autoimmune disease which has caused rupture of red blood cells. Which kind of jaundice is occurring in this patient (or what is the other name for this jaundice)? ________________ A) hepatic jaundice, prehepatic jaundice B) prehepatic jaundice, prehepatic jaundice C) posthepatic jaundice, hepatic jaundice D) hepatic jaundice, hepatic jaundice E) posthepatic jaundice, prehepatic jaundice
posthepatic jaundice, prehepatic jaundice The patient with the gallstone blocking the common bile duct has developed jaundice - yellowing of the eyes and skin due to excessive bile pigments in blood. Which kind of jaundice would be occurring in this patient with common bile duct blockage? posthepatic jaundice Imagine another patient with hemolytic jaundice due to an autoimmune disease which has caused rupture of red blood cells. Which kind of jaundice is occurring in this patient (or what is the other name for this jaundice)? prehepatic jaundice What is occurring in the patient with the gallstone blocking the common bile duct: bile secretions are not reaching the lumen of the small intestine due to obstruction of a bile duct. This means bilirubin cannot be excreted in the feces due to the duct obstruction which causes posthepatic jaundice. The excessive breakdown (hemolysis) of red blood cells...results in the liver being presented with more bilirubin than it is capable of excreting. The patient with the gallstone blocking the common bile duct has posthepatic jaundice and the patient with the autoimmune disease which caused rupture of red blood cells has prehepatic jaundice.
A gallstone is blocking the common bile duct in your patient. You know that the common bile duct is formed when the duct from the liver (the hepatic duct) merges with the duct from the gall bladder (the cystic duct). The blockage of the common bile duct in your patient causes a decrease in bile reaching the lumen of the small intestine compared to a normal person. In this patient no other duct is blocked, that is, the gallstone is not blocking or preventing secretions from the pancreas from reaching the duodenum. This patient ___________have decreased absorption of the products of fat digestion compared to a normal person. A) would B) would not
would This patient would have decreased absorption of the products of fat digestion compared to a normal person. Although the patient would not have decreased lipase secretion from the pancreas (since the pancreatic duct is not blocked), they will have decreased bile release into the duodenum due to the blockage of the common bile duct. With decreased bile release into the duodenum, there would be decreased digestion of fats and decreased absorption of the products of fat digestion. Decreased fat digestion occurs due to decreased bile entering the small intestine and with less bile salts to maintain the lipid emulsion, there would be less surface area for lipase - the fat digesting enzyme from the pancreas - to work on (lipase is water soluble and has to work on the surface of the emulsion droplet). Decreased absorption of the products of fat digestion occurs because with decreased bile salts to help form micelles, the monoglycerides and fatty acids (the products of fat digestion) would tend to huddle together or make a glob since they are not water soluble. So with less bile salts in the small intestine, less fat digestion occurs and less micelle formation occurs, so the absorption of the products of fat digestion would be decreased.
One of your patients is a 4 year old girl named Cecile with cystic fibrosis. You know that while cystic fibrosis has dramatic effects on the respiratory system that you have seen in Cecile and that many people know about, it also has effects on the digestive system which are becoming more of a problem in Cecile. You have told Cecile's family the following: it is a genetic disease that causes the production of thick, dehydrated or viscous or "sticky" mucus. This abnormal, thick mucus can block tubes in the body including the airways of the lungs. The thick mucus can cause airway obstruction (and increased resistance) which causes respiratory symptoms in Cecile. The thick mucus can cause obstruction of other tubes in the body including the pancreatic duct. Recently, Cecile has more and more symptoms involving the digestive system due to obstruction of the pancreatic duct. Due to the pancreatic duct obstruction, Cecile would have a pancreatic _____________ deficiency. A) endocrine B) exocrine
xocrine Due to the pancreatic duct obstruction, Cecile would have a pancreatic exocrine deficiency. Cystic fibrosis causes airway obstruction, but there are other important effects on lung function including that the thick mucus allows many respiratory infections to occur, followed by damage of the lungs. Another clinical feature of the disease is called "pancreatic exocrine deficiency". Pancreatic function is abnormal in most cystic fibrosis patients, though it varies from mild to severe. If the pancreatic duct is obstructed (as it is in Cecile), then the passageway to the duodenum is blocked, and the enzymes of the pancreas or the pancreatic exocrine secretions do not reach the duodenum. It is in the duodenum where the enzymes should function - if they are deficient due to blockage of the duct, then the patient has "pancreatic exocrine deficiency".
One of your patients has a gallstone that is completely blocking the duct that drains the liver, the gall bladder, and the pancreas. The gallstone is blocking the entrance to the duodenum - near the Sphincter of Oddi - after the point where the common bile duct and the pancreatic duct merge (it's called the "hepatopancreatic ampulla"), therefore, bile and pancreatic secretions are not reaching the lumen of the small intestine. Does the blockage of the duct described in the patient in this case affect the absorption of vitamins? _______ Which kind of vitamin absorption would be affected?______ A) no, none B) yes, all C) yes, vitamin B12 D) yes, water soluble E) yes, fat soluble
yes, fat soluble Does the blockage of the duct described in the patient in this case affect the absorption of vitamins? yes Which kind of vitamin absorption would be affected? fat soluble Fat soluble vitamins are carried in micelles and are absorbed with the products of fat digestion. If you don't have bile salts getting into the small intestine due to the blockage described, then absorption of fat soluble vitamins would be decreased. Water soluble vitamins don't need bile salts for absorption, so their absorption should not be affected. Vitamin B12 in choice C is a water soluble vitamin that is bound to intrinsic factor and is absorbed by endocytosis in the terminal ileum but bile salts are not required for its absorption.
Due to the pancreatic duct obstruction, could Cecile have decreased digestion of proteins? _________ Due to the pancreatic duct obstruction, could Cecile have decreased digestion of carbohydrates? _______ A) no, yes B) no, no C) yes, no D) yes, yes
yes, yes Due to the pancreatic duct obstruction, could Cecile have decreased digestion of proteins? yes Due to the pancreatic duct obstruction, could Cecile have decreased digestion of carbohydrates? yes The pancreas secretes protein digesting enzymes (in inactive forms). If blockage of the pancreatic duct prevents these enzymes from being secreted into the duodenum and acting on proteins in the duodenum, then protein digestion would be decreased. The pancreas secretes amylase. If blockage of the pancreatic duct prevents this enzyme from acting in the duodenum, then carbohydrate digestion could be decreased. You would already have some carbohydrate digestion with salivary amylase, but pancreatic amylase won't be secreted into the duodenum in this patient, and even though there would be some digestion of carbohydrates by the disaccharidases on the brush border of the duodenum, carbohydrate digestion would be less than normal because of the decrease in pancreatic amylase in the duodenum. The punch line is: you don't have pancreatic amylase acting on starches in the duodenum then you could have decreased digestion of carbohydrates. Protein and carbohydrate digestion could be decreased in Cecile
Due to the pancreatic duct obstruction, would Cecile have decreased digestion of fats? _______ Could Cecile have "fatty stools" or steatorrhea? _______ A) yes, no B) no, no C) no, yes D) yes, yes
yes, yes Due to the pancreatic duct obstruction, would Cecile have decreased digestion of fats? yes Could Cecile have "fatty stools" or steatorrhea? yes Fat digestion would be decreased in Cecile since lipase from the pancreas won't reach the small intestine in normal amounts. One function of this question is to have you learn where lipase comes from, that is, the pancreas. Fats that are not digested (due to blockage of the pancreatic duct) remain in the GI tract and cause fatty or oily stools which is called steatorrhea. Steatorrhea is symptom of cystic fibrosis.
One of your patients has a gallstone that is completely blocking the duct that drains the liver, the gall bladder, and the pancreas. The gallstone is blocking the entrance to the duodenum - near the Sphincter of Oddi - after the point where the common bile duct and the pancreatic duct merge (it's called the "hepatopancreatic ampulla"), therefore, bile and pancreatic secretions are not reaching the lumen of the small intestine. Would pancreatitis be possible in this patient with complete hepatopancreatic ampulla obstruction? Would this patient in this case have decreased digestion of food compared to a normal person? A) yes, yes B) no, no C) no, yes D) yes, no
yes, yes Would pancreatitis be possible in this patient with complete hepatopancreatic ampulla obstruction? yes Would this patient in this case have decreased digestion of food compared to a normal person? yes Yes, pancreatitis could be possible. It can happen with gall stones obstructing the flow of enzymes from the pancreas which would occur due to obstructing the hepatopancreatic ampulla. This case is similar to what occurred in the cystic fibrosis case in which digestion of food was less than a normal person. In this case (as with the cystic fibrosis case), pancreatic enzymes are not reaching the duodenum. Now it's due to obstruction of the hepatopancreatic ampulla (not the pancreatic duct itself as in the cystic fibrosis case).