WBR0622

Author	[[PageAuthor::Mugilan Poongkunran M.B.B.S [1]]]
Exam Type	ExamType::USMLE Step 3
Main Category	MainCategory::Primary Care Office
Sub Category	SubCategory::Gastrointestinal, SubCategory::Gastrointestinal
Prompt	[[Prompt::A 40 year old female, comes to the office with complaints of fatigue, lethargy, malaise and pruritis for the past few weeks. She recently noticed hyperpigmentation of skin in her upper limbs. Her past history is insignificant and her family history is unremarkable. She has no recent travel exposure outside the country. She denies smoking, alcohol and drugs. Her menstrual cycles are irregular with increased duration of cycles. Her temperature is 36.7 C, blood pressure is 130/70 mmHg, pulse is 102/min and respiartions are 16/min. On examination there is no jaundice, but xanthelasmas and excoriations from scratches with hyperpigmentation are present on skin examination. Abdomen is soft and non-tender with no organomegaly. Other system examinations are normal . Her lab results shows Hb:7 g/dl, hematocrit : 33, Na:135 mEq/L, K: 3 mEq/L, Cl:104mEq/L, Bi: 24 mEq/L, BUN: 30 mg/dl, glucose:176 mg/dl, Mg:1mg/dl and Ca: 8mg/dl. The liver fuction test results are as follows: Alanine aminotransferase : 100 U/L Aspartate aminotransferase : 90 U/L Alkaline phosphatase : 480 U/L Total bilirubin : 1 mg/dl Direct bilirubin : 0.6 mg/dl Hepatits A IgM : negative HbsAg : negative HBc Antibody : negative HCV Antibody : negative Which is the best diagnostic step to confirm the diagnosis in this patient ?]]
Answer A	AnswerA::Antimitochonrial antibodies levels
Answer A Explanation	AnswerAExp::'''Incorrect''' : Most anti-mitochondrial antibodies assays are almost as sensitive and specific for PBC as liver biopsy, but diagnostic confirmation always requires liver biopsy.
Answer B	AnswerB::Anti-smooth muscle antibodies and immunoglobin levels
Answer B Explanation	[[AnswerBExp::Incorrect : Lupoid hepatitis (also called Autoimmune hepatits) is an auto-immune disease which causes liver cirrhosis. It may be associated with systemic lupus erythematosus (SLE) or other connective tissue disorders. 60% of patients have chronic hepatitis that may mimic viral hepatitis, but without serologic evidence of a viral infection. The disease usually affects women and is strongly associated with anti-smooth muscle auto-antibodies. They usually have elevated transaminases levels greater than that of alkaline phosphatase levels.]]
Answer C	AnswerC::Serum LDL, VLDL and TG levels
Answer C Explanation	[[AnswerCExp::Incorrect : Hypercholesterolemia is a common feature of primary biliary cirrhosis (PBC) and other forms of cholestatic liver disease. The mechanism of hyperlipidemia in cholestatic disorders is different from that in other conditions as unusual lipoprotein particles, such as lipoprotein X, may accumulate and levels of HDL cholesterol are typically elevated. But this is not a confirmatory test.]]
Answer D	AnswerD::Liver biopsy
Answer D Explanation	[[AnswerDExp::Incorrect : Diagnostic confirmation for primary biliary cirrhosis requires liver biopsy which gives a clear cut idea about the stage and prognosis.]]
Answer E	AnswerE::Iron studies and genetic testing
Answer E Explanation	[[AnswerEExp::Incorrect : Hereditary hemochromatosis is an autosomal recessive disorder in which mutations in the HFE gene cause increased intestinal iron absorption. The most common symptoms were extreme fatigue, arthralgia, loss of libido, skin hyperpigmentation due to iron deposition and melanin. The classic triad of cirrhosis, diabetes mellitus, and skin pigmentation ("bronze diabetes") occurs late in the disease. They usually have elevated transaminases levels greater than that of alkaline phosphatase levels.]]
Right Answer	RightAnswer::D
Explanation	[[Explanation::Primary biliary cirrhosis (PBC) is an autoimmune disease of the liver marked by the slow progressive destruction of the small bile ducts (bile canaliculi) within the liver. When these ducts are damaged bile builds up in the liver (cholestasis) and over time damages the tissue. This can lead to scarring, fibrosis, cirrhosis, and ultimately liver failure. Pruritus, hyperpigmentation of the skin, and hepatomegaly in a woman with a cholestatic pattern of liver function tests is common in PBC but unusual in other liver disorders such as acute and chronic hepatitis and alcoholic liver disease. Serum alkaline phosphatase concentration is almost always elevated, often to striking levels with serum levels of 5'-nucleotidase and gammaglutamyl transpeptidase paralleling alkaline phosphatase levels. The serum levels of aminotransferases may be normal or slightly elevated and antimitochondrial antibodies are the serologic hallmark of PBC. Educational Objective: References: ]]
Approved	Approved::Yes
Keyword	WBRKeyword::Primary biliary cirrhosis, WBRKeyword::Autoimmune hepatitis, WBRKeyword::Hemochromatosis
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