A 45-year-old man goes to an emergency department because he is experiencing severe abdominal pain, which is radiating straight through to his back. The pain began several hours after an admitted alcoholic binge, and has not changed in position, although it has become worse.
Q 1
Which of the following would be the most likely cause of this type of pain?
/ A. Acute appendicitis
/ B. Acute hepatitis
/ C. Acute pancreatitis
/ D. Chronic hepatitis
/ E. Myocardial infarction
Q 2
In addition to alcohol use, which of the following is a common predisposing factor for this patient's disease?
/ A. Biliary tract stones
/ B. Duodenal cancer
/ C. Gastric carcinoma
/ D. Kidney stones
/ E. Peptic ulcer
Q 3
Marked serum elevation of which of the following markers would most strongly substantiate the likely diagnosis?
/ A. Acid phosphatase
/ B. Amylase
/ C. Aspartate aminotransferase
/ D. AIkaline phosphatase
/ E. Creatinine kinase
Q 4
The patient has a severe course that requires treatment in an ICU. CIinically, he appears similar to patients with sepsis, with fever, elevated white count, hypotension, increased pulse rate, shallow and rapid breathing, oliguria, and a blunted sensorium, in addition to his pain and abdominal tenderness. These clinical findings are most likely related to which of the following?
/ A. Activation of the inflammatory cascade
/ B. AIcohol withdrawal symptoms
/ C. AIIergic reaction to alcohol
/ D. Drug toxicity effect
/ E. Secondary infection with mixed flora gut bacteria
Q 5
The patient's condition resolves in about two weeks, but he continues to drink after leaving the hospitaI. When seen several years later, he has had a number of similar episodes, and now has chronic severe abdominal pain. CT scan demonstrates a single, smooth-walled, fluid filled space in the tail of the pancreas, which can be reached by the radiologist for CT-guided aspiration with an approach from the back. The fluid aspirated is yellowish, clear, and acellular. Which of the following is the most likely diagnosis?
/ A. Pancreatic microcystic adenoma
/ B. Pancreatic mucinous cystadenocarcinoma
/ C. Pancreatic mucinous cystadenoma
/ D. Pancreatic pseudocyst
/ E. Pancreatic solid-cystic tumor
Abdominal Pain Case 4 Answers
A1
The correct answer is C. The typical pain described occurs in approximately 50% of patients with acute pancreatitis. Other patients may have milder pain or even, uncommonly, pain first felt in the lower abdomen.
The pain of acute appendicitis (choice A) is often felt first as referred pain near the umbilicus, with tenderness on palpation in the left lower quadrant.
Acute hepatitis (choice B) can cause pain referred to the right shoulder.
Chronic hepatitis (choice D) does not usually cause pain.
Myocardial infarction (choice E) can cause substernal pain and pain radiating to the left shoulder.
A2
The correct answer is A. The overwhelmingly most common predisposing factors for acute pancreatitis are gallstones (more specifically tiny ones that lodge in the extrahepatic bile duct system) and alcohol abuse.
Rarely, nearby cancers (choices B and C) can occlude the pancreatic duct system and cause a secondary acute pancreatitis.
Kidney stones (choice D) have no relationship with pancreatitis.
Peptic ulcers (choice E) that erode into the pancreas can uncommonly secondarily inflame the pancreas
A3
The correct answer is B. The usual markers for pancreatitis are amylase and lipase. Marked elevation of amylase usually means either pancreatic disease or salivary gland disease; lipase will be elevated in pancreatic disease but not salivary gland disease. If you see elevated amylase on a USMLE question, you should think of pancreatitis or salivary gland disease (mumps, salivary gland stone). However, you should be aware, for your general medical knowledge, that modest elevations of amylase can be seen in a much wider variety of settings (often reflecting either subclinical pancreatic damage or hemoconcentration of pancreatic enzymes), including GI obstruction, mesenteric thrombosis and infarction, macroamylasemia (a genetic condition with abnormal amylase), renal disease, ruptured tubal pregnancy, lung cancer, acute alcohol ingestion, and following abdominal surgery.
Associate acid phosphatase (choice A) with diseases involving the prostate and, to lesser degrees, bone, the heart, platelets, and the liver.
Associate aspartate aminotransferase (choice C) with diseases of the heart, muscle, liver, pancreas (though not as important for diagnosis as amylase and lipase), and brain.
Associate alkaline phosphatase (choice D) with diseases of bone, liver, and to lesser degrees, lung and heart.
Associate creatinine kinase (choice E) with diseases of the heart, muscle, brain, and the general body (trauma, surgery).
A4
The correct answer is A. Acute pancreatitis can either be relatively mild, or a severe condition that may cause death. It is thought that, in severe cases, leakage of enzyme-containing pancreatic secretions into the tissues/and or blood stream causes cleavage of precursors, thus strongly activating the complement and inflammatory cascades. These, in turn, produce abundant cytokines, which worsen the symptoms. The clinical result is similar to sepsis, with risk of multi-organ failure and death. The treatment of acute pancreatitis is primarily supportive, and may include careful attention to fluid resuscitation, oxygen supplementation, cardiovascular support, dialysis, management of electrolyte abnormalities, pain control, and total parenteral nutrition.
Alcohol allergy (choice C) or withdrawal (choice B) do not play any additional part in most of these symptoms once the pancreatitis has developed.
Infection (choice E) and drug toxicity (choice D) are also not a necessary part of the clinical picture, although physicians may worry that the patient's general clinical status is masking other, potentially more treatable, problems.
A5
The correct answer is D. Pancreatic pseudocyst is a fairly common complication of both acute and chronic pancreatitis, and appears to develop when trapping of pancreatic digestive juices (containing amylase, lipase, and proteases) causes a "digestion" of part of the pancreas, leaving a fluid filled cystic space. The term "pseudocyst", rather than "cyst", is used by purists because the space does not have an epithelial lining, and is hence not a "true cyst". Pseudocysts are usually solitary and typically measure 5-10 cm in diameter. They can be surgically excised (and the surrounding tissue will typically show evidence of chronic pancreatitis in long-standing cases) or sometimes, if the anatomy is favorable, drained into adjacent hollow viscera. Some are medically managed if small.
Most true neoplasms of the pancreas contain (often large numbers of) smaller, multiple, cysts. These tumors can be benign or malignant, and the ones with mucus-secreting epithelium (choices B and C) are more common than those with a serous lining (choices A and E).
Posts
No comments:
Post a Comment