WBR0729

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Author [[PageAuthor::Rim Halaby, M.D. [1]]]
Exam Type ExamType::USMLE Step 1
Main Category MainCategory::Pathology
Sub Category SubCategory::Gastrointestinal
Prompt [[Prompt::A 47 year old male patient, with a history of chronic alcohol consumption, presents to the physician's office for recurrence of abdominal pain that radiates to the back. The patient's past medical history is significant for cholecystectomy and recurrent attacks of pancreatitis for more than 10 years. Upon further questioning, the patient also notes he has stools that are difficult to flush and has been recently diagnosed with diabetes mellitus. Following appropriate work-up, a wedge biopsy of the pancreas is performed and the diagnosis of alcoholic chronic pancreatitis is made. Which of the following statements is true about alcoholic chronic pancreatitis?]]
Answer A AnswerA::Caucasians are at increased risk of alcoholic chronic pancreatitis compared to African-Americans
Answer A Explanation AnswerAExp::African-Americans are at increased risk of alcoholic chronic pancreatitis.
Answer B AnswerB::Chronic pancreatitis is due to inefficient ethanol processing within the pancreas
Answer B Explanation AnswerBExp::Although ethanol is efficiently metabolized by the pancreas, its metabolites activate stellate cells and damage pancreatic acinar cells.
Answer C AnswerC::Ethanol metabolites activate pancreatic stellate cells
Answer C Explanation AnswerCExp::Ethanol metabolites damage acinar cells and activate stellate cells that lead to fibrosis and chronic pancreatitis.
Answer D AnswerD::Excessive alcohol consumption is the predominant factor in more than 80% of chronic pancreatitis
Answer D Explanation [[AnswerDExp::Chronic pancreatitis is associated with alcohol consumption, but excessive consumption is seen in only 30-35% of the cases. Hence, it is believed that other factors, in addition to amount of consumed alcohol, also play a significant role in the development of chronic pancreatitis.]]
Answer E AnswerE::Alcoholic chronic pancreatitis is less common than infectious etiologies of pancreatitis among adults.
Answer E Explanation AnswerEExp::Alcoholic chronic pancreatitis is a much more common cause of chronic pancreatitis. In the adult population, infectious etiology is considered rare.
Right Answer RightAnswer::C
Explanation [[Explanation::Alcoholic chronic pancreatitis is the most common cause of chronic pancreatitis among adults in otherwise healthy patients. Alcoholic chronic pancreatitis is more common among the African-American population compared to other ethnicities. is in fact believed to be less associated with the amount of excessive alcohol consumption, since excess consumption is responsible for approximately only 30% of alcoholic chronic pancreatitis. Furthermore, pancreatic injury from alcohol may occur using very small doses; thus there may be no real threshold for the amount needed to induce chronic pancreatitis.

Despite the efficient ethanol processing, its metabolites damage pancreatic acinar cells and activate stellate cells that contribute to fibrosis and chronic pancreatitis, with reduced exocrine and endocrine pancreatic functions (such as steatorrhea and diabetes mellitus in this patient).

Stellate cells of the pancreas are special cells found in pancreatic regions that contain exocrine activity. They are cells that resemble myofibroblasts and are activated during tissue damage, which causes their proliferation and migration into injured sites for reparation of tissue by phagocytosing and synthesizing new extracellular matrix structures.

Chronic activation of pancreatic stellate cells is associated with fibrotic changes and chronic pancreatitis and pancreatic cancer.

Educational Objective: Alcoholic chronic pancreatitis is associated with the activation of pancreatic stellate cells by ethanol metabolites. Chronic stellate cell activations leads to fibrosis and chronic pancreatitis.

References:

Braganza JM, Lee SH, McCloy RF, McMahon MJ. Chronic pancreatitis. Lancet; 2011;377:1184-97.

Omary MB, Lugea A, Lowe AW, Pandol SJ. J Clin Invest. 2007; 117(1):50-59.
Educational Objective:
References: ]]

Approved Approved::No
Keyword WBRKeyword::chronic, WBRKeyword::pancreatitis, WBRKeyword::stellate, WBRKeyword::cells, WBRKeyword::alcoholic, WBRKeyword::abdominal, WBRKeyword::pain, WBRKeyword::steatorrhea, WBRKeyword::diabetes, WBRKeyword::mellitus, WBRKeyword::wedge, WBRKeyword::biopsy, WBRKeyword::fibrosis, WBRKeyword::ethanol, WBRKeyword::alcohol
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