MLPAO Clinical Chemistry Advanced Concepts Flashcards
6 cards from real MLPAO practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 MLPAO Clinical Chemistry Advanced Concepts flashcards as text
Which enzyme is measured to confirm the hepatic origin of an elevated alkaline phosphatase?
Answer: Gamma-glutamyltransferase (GGT)
GGT is used to confirm the hepatic origin of an elevated alkaline phosphatase. If both ALP and GGT are elevated, the ALP is likely of hepatobiliary origin. If ALP is elevated but GGT is normal, the ALP elevation is likely from bone or other non-hepatic sources.
What is the significance of measuring C-reactive protein (CRP) in clinical chemistry?
Answer: Detecting and monitoring inflammation and infection
CRP is an acute phase protein produced by the liver in response to inflammation. It rises rapidly (within 6-8 hours) and can increase up to 1000-fold during acute infection or inflammation. High-sensitivity CRP (hs-CRP) is also used for cardiovascular risk assessment.
Which method is considered the gold standard for measuring serum osmolality?
Answer: Freezing point depression osmometry
Freezing point depression osmometry is the gold standard for measuring serum osmolality. It measures all osmotically active particles in solution by detecting the depression of the freezing point below that of pure water. Each osmol of solute depresses the freezing point by 1.86°C.
What is the clinical significance of an elevated serum lipase compared to amylase in suspected pancreatitis?
Answer: Lipase remains elevated longer and is more specific for pancreatic injury
Serum lipase is more specific for pancreatic disease than amylase and remains elevated for a longer duration (up to 14 days vs 3-5 days for amylase). Many Canadian guidelines now recommend lipase as the preferred single test for diagnosing acute pancreatitis.
Which specimen collection error would falsely decrease measured serum calcium?
Answer: Collecting in an EDTA tube instead of a red-top tube
Collecting blood in an EDTA tube (lavender top) for calcium measurement would give falsely decreased results because EDTA chelates (binds) calcium ions. EDTA is an anticoagulant that works specifically by removing calcium, which is essential for the coagulation cascade.
What does a high serum ferritin level with low serum iron and low TIBC suggest?
Answer: Anemia of chronic disease
Anemia of chronic disease (ACD) is characterized by high ferritin (reflecting adequate iron stores), low serum iron (iron is sequestered and unavailable), and low TIBC (reduced transferrin production). This pattern distinguishes ACD from iron deficiency, where ferritin is low and TIBC is elevated.