Clinical Chemistry Flashcards
Which of the following is considered a lipid?
a. Chylomicrons
b. LDL
c. Cholesterol
d. HDL
c. Cholesterol
In the laboratory procedure for the quantification of
HDL, the purpose of the dextran sulfate is to:
a. Precipitate all Apo A1 containing lipoproteins
b. Covert cholesterol esters to cholesterol for detection
c. Precipitate all Apo B and Apo A containing
lipoproteins
d. Precipitate all Apo B containing proteins
d. Precipitate all Apo B containing proteins
Which of the following lipoproteins is the smallest of all the lipoproteins and is composed of 50% protein?
a. HDL
b. Chylomicrons
c. LDL
d. Triglycerides
a. HDL
Which of the following would be most adversely
affected by a non-fasting sample?
a. HDL
b. LDL
c. Cholesterol
d. Triglycerides
d. Triglycerides
Which of the following apoproteins is responsible for receptor binding for IDL and the chylomicron remnant produced in fat transport?
a. Apo A1
b. Apo C
c. Apo E
d. Apo B
c. Apo E
Which of the following enzymes is found bound to
HDL and LDL in blood plasma and acts to convert
free cholesterol into cholesteryl esters?
a. Cholesterol esterase
b. Cholesterol oxidase
c. Lecithin-cholesterol acyltransferase
d. Lipase
c. Lecithin-cholesterol acyltransferase
Which of the following blood samples would serve
best to assay lipoproteins because this anticoagulant
acts to preserve lipoproteins?
a. EDTA plasma sample
b. Heparin plasma sample
c. Citrate plasma sample
d. Fluoride plasma sample
a. EDTA plasma sample
Exogenous triglycerides are transported in the
plasma in which of the following forms?
a. VLDL
b. Chylomicrons
c. LDL
d. Cholesteryl esters
b. Chylomicrons
A patient presents to his physician for a lipid profile.
The following results are received:
HDL1⁄450 mg/dL
Total cholesterol1⁄4300 mg/dL Triglycerides1⁄4200 mg/dL
The calculated LDL cholesterol is:
a. 200
b. 210
c. 290
d. 350
b. 210
According to the National Cholesterol Education
Program, which lipid or lipoprotein class is more
important for therapeutic decision making (diet
and medication decisions)?
a. Chylomicrons
b. LDL
c. HDL
d. Cholesterol
b. LDL
Which of the following mechanisms accounts for the elevated plasma level of b-lipoproteins seen in hyperbetalipoproteinemia (Fredrickson’s type II lipoproteinemia)?
a. Elevated insulin found in these patients
b. Apo B-100 receptor defect
c. Apo C-II–activated lipase deficiency
d. LCAT deficiency
b. Apo B-100 receptor defect
Which enzyme is common to all enzymatic methods
for triglyceride measurement?
a. Glycerol phosphate oxidase
b. Glycerol phosphate dehydrogenase
c. Pyruvate kinase
d. Glycerol kinase
d. Glycerol kinase
A patient sample is assayed for fasting triglycerides and a triglyceride value of 1036 mg/dL. This value is of immediate concern because of its association with which of the following conditions?
a. Coronary heart disease
b. Diabetes
c. Pancreatitis
d. Gout
c. Pancreatitis
Which of the following apoproteins is inversely related to risk for coronary heart disease and is a surrogate marker for HDL?
a. Apo A-I
b. Apo B
c. Apo B100
d. APO E
a. Apo A-I
What is the most appropriate fasting procedure when a lipid study of triglycerides, total cholesterol, HDL,
and LDL tests are ordered?
a. 8 hours, nothing but water allowed
b. 10 hours, water, smoking, coffee, tea (no sugar or cream) allowed
c. 12 hours, nothing but water allowed
d. 16 hours, water, smoking, coffee, tea (no sugar or
cream) allowed
c. 12 hours, nothing but water allowed
John Smithers (21 years of age) is in to see his physician for a pre-college physical and checkup. John has always been extremely healthy. The following
laboratory results are received:
AStandard1⁄40=679 AControl1⁄40=650
ASmithers1⁄40=729 CStandard1⁄4=200 mg/dL
Control range 190-195 mg/dL
John’s cholesterol concentration is approximately:
a. 186 mg/dL
b. 199 mg/dL
c. 209 mg/dL
d. 215 mg/dL
c. 209 mg/dL
Sucrose is considered a disaccharide that on hydrolysis yields which of the following sugars?
a. Glucose
b. Galactose and glucose
c. Maltose and glucose
d. Fructose and glucose
d. Fructose and glucose
Laboratory tests are performed for a postmenopausal, 57-year-old woman as part of an annual physical examination. The patient’s random serum glucose is 220 mg/dL, and the glycated hemoglobin (HbA1c) is 11%. Based on this information, this
patient would mostly likely be classified as:
a. Normal
b. Impaired
c. Having type 1 diabetes
d. Having type 2 diabetes
d. Having type 2 diabetes
Which of the biochemical processes below is promoted by insulin?
a. Glycogenolysis
b. Gluconeogenesis
c. Esterification of cholesterol
d. Uptake of glucose by the cells
d. Uptake of glucose by the cells
At what serum glucose concentration would glucose
begin to appear in the urine?
a. 50 mg/dL
b. 75 mg/dL
c. 100 mg/dL
d. 170 mg/dL
d. 170 mg/dL
Which of the following laboratory tests is the best marker to detect patients with diabetes who are at
risk for developing diabetic nephropathy?
a. Creatinine
b. BUN
c. Microalbuminuria test
d. Glucose
c. Microalbuminuria test
A 68-year-old obese woman visits her doctor reporting increased urination (especially at night), increased thirst, and increased appetite. Her glucose
on examination was 210 mg/dL (fasting). Which of the following statements best fits with the given
information above?
a. The patient most likely has type 1 diabetes mellitus
b. The patient would show a positive glucose in her urine
c. The patient would have a decreased glycated hemoglobin
d. Additional testing of this patient should include assessment of hypoglycemia
b. The patient would show a positive glucose in her urine
Which of the following hemoglobin A1c results represents an impaired state according to the American Diabetes Association?
a. 4.5%
b. 5.5%
c. 6.0%
d. 6.5%
c. 6.0%
A plasma glucose result is 100 mg/dL. The corresponding glucose in whole blood would approximate:
a. 58 mg/dL
b. 87 mg/dL
c. 98 mg/dL
d. 114 mg/dL
b. 87 mg/dL
Which of the following methods is virtually specific for glucose and employs G6PD as a second coupling
step requiring magnesium?
a. Hexokinase
b. Glucose oxidase
c. Glucose dehydrogenase
d. Pyruvate kinase
a. Hexokinase
A 62-year-old patient presents to the physician with report of increased thirst and increased urination,
particularly at night. The physician requests a series of tests over the next few days. The following data
are received:
Analyte
Random glucose - 186 mg/dL
Fasting glucose - 114 mg/dL
2-Hour OGTT - 153 mg/dL
HbA1c - 5.9%
Which of the following conclusions may be made regarding these data?
a. Data represents normal glucose status
b. Data represents an impaired glucose status
c. Data represents the presence of an insulinoma
d. Data represents the diagnosis of diabetes
b. Data represents an impaired glucose status
Which of the following renal conditions is associated with a recent group A b-hemolytic streptococcus
infection?
a. Kidney obstruction
b. Acute renal failure
c. Uremic syndrome
d. Acute glomerulonephritis
d. Acute glomerulonephritis
The red complex developed in the Jaffe method to determine creatinine measurements is a result of the
complexing of creatinine with which of the following?
a. Alkaline picrate
b. Diacetyl monoxide
c. Sulfuric acid
d. Sodium hydroxide
a. Alkaline picrate
The kidney is responsible for acid-base balance through the removal of H ions via four major mechanisms. Which of the following describes one of those mechanisms?
a. Reabsorption of H ions in the proximal convoluted tubule
b. Reaction of H ions with Na in the descending loop of Henle
c. Reaction of H ions with filtered bicarbonate ions
d. Reaction of H ions with ADH in the
collecting ducts
c. Reaction of H ions with filtered bicarbonate ions
Which formula is most accurate in predicting plasma osmolality?
a. Na + 2(Cl) +BUN +Glucose
b. 2(Na) + 2 (Cl) +Glucose + BUN
c. 2(Na) +Glucose/18 +BUN/2.8
d. 2(BUN) +Glucose/18 + Cl/2.8
c. 2(Na) +Glucose/18 +BUN/2.8
Which of the following statements regarding serum urea is true?
a. Levels are independent of diet
b. High BUN levels can result from necrotic liver
disease
c. BUN is elevated in pre renal as well as renal failure
d. BUN rises earlier and quicker than creatinine in renal damage
c. BUN is elevated in pre renal as well as renal failure
Osmolality can be defined as a measure of the concentration of a solution based on:
a. The number of particles present
b. The number and size of particles present
c. The density of particles present
d. The isoelectric point of a particle
a. The number of particles present
An increased osmole gap is most commonly seen in which of the following?
a. Type 2 diabetes
b. Pancreatitis
c. Presence of toxins such as ethanol and ethylene glycol
d. Liver failure
c. Presence of toxins such as ethanol and ethylene glycol
A patient with type 2 diabetes is in for a routine examination with the physician. A series of laboratory tests are performed, including calculation of an eGFR. The patient’s calculated eGFR is 64 mL/min. This result is most indicative of:
a. A normal state
b. Abnormal glucose control
c. Mild kidney damage
d. Kidney failure
c. Mild kidney damage
A healthy 28-year-old female sees her physician for a routine examination and receives a “relatively” clean
bill of health except for the results below.
Total bilirubin 2.8 mg/dL
Direct bilirubin 0.1 mg/dL
Indirect bilirubin 2.7 mg/dL
These results most likely indicate which of the following?
a. Normal bilirubin metabolism
b. Extrahepatic obstruction
c. Dubin-Johnson syndrome
d. Gilbert’s disease
d. Gilbert’s disease
Which of the following is measured using glutamate dehydrogenase and is a measure of advanced stages,
poor prognosis, and coma in liver disease?
a. Total bilirubin
b. Ammonia
c. Unconjugated bilirubin
d. Urea
b. Ammonia
In which of the following disease states would you see an elevation in total bilirubin and conjugated bilirubin only?
a. Biliary obstruction
b. Hemolysis
c. Neonatal jaundice
d. Hepatitis
a. Biliary obstruction
In which of the following conditions does no activityof glucuronyl transferase result in increased unconjugated bilirubin and kernicterus in neonates and even-
tual death within 18 months?
a. Gilbert’s disease
b. Dubin-Johnson syndrome
c. Crigler-Najjar syndrome
d. Intravascular hemolysis
c. Crigler-Najjar syndrome
As a reduction product of bilirubin catabolism, this compound is partially reabsorbed from the intestines
through the portal circulation for re-excretion by the liver. What is this compound?
a. Urobilinogen
b. Azobilirubin
c. Biliverdin
d. Urobilin
a. Urobilinogen
In the liver, bilirubin is conjugated in the presence of which of the following?
a. b-Glucuronidase
b. Bilirubin oxidase
c. Uridine diphosphate (UDP) glucuronyl transferase
d. Peroxidase
c. Uridine diphosphate (UDP) glucuronyl transferase
Hepatocellular damage may be best assessed by which of the following parameters?
a. Serum AST and ALT levels
b. GGT and ALP
c. Bilirubin, GGT, and ALP
d. Ammonia and urea
a. Serum AST and ALT levels
Which of the following conditions is caused by deficient secretion of bilirubin into the bile canaliculi?
a. Gilbert’s disease
b. Physiologic jaundice of the newborn
c. Dubin-Johnson syndrome
d. Hemolytic jaundice
c. Dubin-Johnson syndrome
Which of the following enzymes is responsible for the conjugation of bilirubin?
a. Biliverdin reductase
b. Peroxidase
c. UDP–glucuronyl transferase
d. b-Glucuronidase
c. UDP–glucuronyl transferase
Which of the following analytes is the best indicator of hepatobiliary damage?
a. AST
b. ALT
c. ALP
d. Bilirubin
c. ALP
Which of the following fractions of bilirubin in high concentrations is associated with kernicterus in
newborns?
a. Delta bilirubin
b. Unconjugated bilirubin
c. Conjugated bilirubin
d. Unconjugated and delta bilirubin
b. Unconjugated bilirubin
The characteristic laboratory finding in alcoholic cirrhosis includes:
a. Moderate elevations in AST and ALT, normal GGT, and normal ALP
b. Slight elevations in AST and ALT, marked elevations in ALP, normal GGT
c. Slight elevations in AST, ALT, and GGT and marked elevations in 50 nucleotidase
d. Slight elevations in AST and ALT (AST>ALT), marked elevations in GGT, slight elevations in ALP
d. Slight elevations in AST and ALT (AST>ALT), marked elevations in GGT, slight elevations in ALP
Which of the following liver conditions shows an increase in both conjugated bilirubin and ALP, manifests with anti-mitochondrial antibodies, and shows
a characteristic lipoprotein X on electrophoresis?
a. Hemochromatosis
b. Primary biliary cirrhosis
c. Alcoholic fatty liver
d. Hepatic tumors
b. Primary biliary cirrhosis
Which set of results is consistent with uncompensated metabolic acidosis?
a. pH 7.25, HCO3 15 mmol/L, PCO2 37 mm Hg
b. pH 7.30, HCO3 16 mmol/L, PCO2 28 mm Hg
c. pH 7.45, HCO3 22 mmol/L, PCO2 40 mm Hg
d. pH 7.40, HCO3 25 mmol/L, PCO2 40 mm Hg
a. pH 7.25, HCO3 15 mmol/L, PCO2 37 mm Hg
A patient with emphysema who has fluid accumulation in the alveolar sacs (causing decreased ventilation) is likely to be in which of the following
acid-base clinical states?
a. Respiratory alkalosis
b. Respiratory acidosis
c. Metabolic acidosis
d. Metabolic alkalosis
b. Respiratory acidosis
Which of the following buffer systems is the most important physiologic buffer system in the body?
a. Hemoglobin
b. Protein
c. Phosphate
d. Bicarbonate/carbonic acid
d. Bicarbonate/carbonic acid
To maintain electrical neutrality in the red blood cell, bicarbonate leaves the red blood cell and enters the plasma through an exchange mechanism with which of the following?
a. TCO2
b. Sodium
c. Chloride
d. Phosphate
c. Chloride
Increased PCO2 in a patient most commonly results in which of the following primary acid-base abnormalities?
a. Respiratory acidosis
b. Metabolic acidosis
c. Respiratory alkalosis
d. Metabolic alkalosis
a. Respiratory acidosis
Which of the following changes will occur with a blood gas sample exposed to room air?
a. pH increased
b. pCOO2 increased
c. pO2 decreased
d. Ionized calcium increased
a. pH increased