Chemistry ASCP Practice
What medication is known to cause Reye's Syndrome in children?
Acetylsalicylic acid (aspirin)
Which disease/condition is associated with a deficiency in thiamine?
Beriberi
What test is not required for the diagnosis of hereditary hemochromatosis?
Biopsy of liver and/or bone marrow
To assess drug concentrations during the trough phase:
Blood should be drawn immediately before the next dose is given.
All cells can synthesize heme, what two organs are the main sites of hemoglobin synthesis for the body?
Bone marrow and the liver
What tumor marker is used for colorectal cancer?
CEA
What tumor marker is widely used for the detection of colorectal cancers?
CEA
Following a myocardial infarction, which of the following enzymes will be the first to become elevated? CK LDH GGT ALT
CK
Which three genetic variations in enzymes are most often linked to differences in drug metabolism?
CYP2D6, CYP2C9, & CYP3A4 (of the cytochrome P-450 family)
What is the purpose of the BUN test?
Determines the amount of urea in blood
Which of the following therapeutic drugs increases the force of myocardial muscle contraction? Primidone Cyclosporine Digoxin Disopyramide
Digoxin (inhibits Na+ and K+ influx in myocardial cells)
Maltose, lactose, and sucrose are all:
Disaccharides
Electrophoretic separation of hemoglobin fundamentally relies on:
Electrical charge differences of molecules
What symptoms will patients with hereditary hemochromatosis have?
Elevated transferrin saturation, often possess a genetic mutation affecting iron metabolism, and an increased serum ferritin
The normal De Ritis ratio (AST/ALT) should be:
Equal or < 1
Ninety-nine percent of lead absorbed in the body is taken up by what after absorption?
Erythrocytes
All of the following variables related to the collection of blood may falsely increase the potassium levels EXCEPT: Drawing a purple-top EDTA tube prior to a red-top tube. Mixing the blood collection tube aggressively. Pouring some sample from a purple-top EDTA tube into a red-top tube to make up for low collection volume. Using a 21 G needle with a 10 mL collection tube.
Using a 21 G needle with a 10 mL collection tube.
Bioavailability of an oral drug refers to the:
Fraction of the drug that is absorbed into systemic circulation
All of the following hormones are produced primarily in the pancreatic islets EXCEPT which one? Gastrin Glucagon Insulin Pancreatic polypeptide
Gastrin
Hydrogen ion concentration (pH) in blood is usually determined by means of which of the following electrodes? Silver Glass Platinum Platinum-lactate
Glass
Which of the following serum constituents is unstable if a blood specimen is left standing at room temperature for eight hours before centrifugation and processing? Cholesterol Triglyceride Creatinine Glucose
Glucose
What tests are included in a renal function panel?
Glucose, BUN, creatinine, sodium, potassium, chloride, CO2, calcium, albumin, phosphorous
Which compound normally contains the majority of the body's total iron?
Hemoglobin
A specimen for potassium was drawn in a tube without anticoagulant at 6 AM during a traumatic patient stick. The results were 6.0 mmol/L. Why are the results elevated?
Hemolysis of the RBCs
What type of anticoagulant is generally suitable for TDM analysis?
Heparin
All of the following anticoagulants will produce a significant effect on calcium levels in plasma, EXCEPT: EDTA Heparin Oxalates Citrates
Heparin (The others remove calcium ("chelate") from blood. Heparin prevents coagulation by forming a complex with antithrombin III and stops the coagulation cascade.)
Increased concentrations of alpha-fetoprotein (AFP) in adults are MOST characteristically associated with:
Hepatocellular carcinoma
Fluorometers are designed so that the path of the excitation light is a right angle to the path of the emitted light. What is the purpose of this design?
Prevent incident light from striking the detector
The MOST accurate observation about osmotic pressure is that it is:
Proportional to concentration of solute particles
All of the following conditions would be associated with an increased level of alpha-fetoprotein EXCEPT: Prostate cancer Hepatocellular carcinoma Viral hepatitis Testicular tumors
Prostate cancer
What antigen is commonly used to screen for prostate cancer?
Prostate-specific antigen (PSA)
Which condition is caused by the increased Plasminogen Activator Inhibitor 1 (PAI-1) and fibrinogen often present in metabolic syndrome?
Prothrombic state
What organism grows as black colonies on XLD agar plate?
Salmonella serotype typhi
What are the primary reagent components used in the Jaffe reaction for creatinine?
Saturated picric acid and sodium hydroxide
Patients with Cushing's disease typically exhibit:
Serum cortisol overproduction
All of the following would be significantly increased in a plasma sample as a result of hemolysis EXCEPT: Potassium LDH Sodium AST
Sodium (major cation of ECF, not much found inside cells)
All of the following carbohydrates are considered reducing sugars EXCEPT: Lactose Sucrose Glucose Ribose
Sucrose
What test can be used as a confirmatory test for proteinuria?
Sulfosalicylic acid test (SSA)
What is the drug cyclosporine used for?
Suppress graft rejection of transplanted organs (it's an immunosuppressor)
What cell secretes hyaluronic acid?
Synoviocytes
Glucoronic acid is used in the liver for conjugating what compound from hemoglobin degradation?
Unconjugated bilirubin
Which purine base is found in RNA and not in DNA?
Uracil
What is the name of the colorless end product of bilirubin catabolism?
Urobilinogen
The ultimate end product of both epinephrine and norepinephrine metabolism is:
Vanillymandellic acid (VMA)
Carbon dioxide is predominantly found in blood in the form of:
bicarbonate ions
The function of the very low density lipoproteins (VLDLs) is to transport:
endogenous triglycerides
What organisms belong to kingdom Protozoa?
flagellates and ciliates
pH in blood is usually determined by means of what type of electrode?
glass
Which marker is most useful for detection of gestational trophoblastic disease?
hCG (human chorionic gonadotropin)
The recommended storage temperature for the preservation of activity for MOST enzymes is:
4 C
What transferrin saturation would be indicative to investigate further for hereditary hemochromatosis (HH)? 40% 45% 35% 25%
45%
What does a lipid panel consist of?
Cholesterol, lipoprotein, high density cholesterol (HDL), triglycerides
A 45-year-old male of average height and weight had a serum creatinine of 1.5 mg/dL and urine creatinine was 120 mg/dL; the total volume of urine collected over a 24-hour period was 1800 mL. Calculate the creatinine clearance for this patient in mL/min.
100 mL/min
After an acute myocardial infarction (AMI), myoglobin levels will rise within 3 hours and peak at 8-12 hours. When will they return to normal?
18-30 hours
Using the formula for creatinine clearance, calculate the clearance based on the values given below: Urine creatinine: 100 mg/dL Plasma creatinine: 1.9 mg/dL Urine volume: 1375 mL/24 hours Surface area: 1.2 m^2 Round to 1 decimal place
72 mL/min/m^2
When the body compensates for a respiratory or metabolic disorder, the MAIN goal is to achieve:
A normal pH
What is the most common subgroup of A?
A1
Which adipokine is decreased in obesity, is anti-inflammatory, and increases insulin sensitivity?
Adiponectin
The Emergency Department has collected blood test tubes for potassium, albumin, plasma hemoglobin, and acid phosphatase. Which of these test results will NOT be negatively affected if the blood tube is sent by the hospital's pneumatic tube system?
Albumin
Which of the following proteins has the FASTEST electrophorectic mobility? Albumin Alpha globulins Beta globulins Gamma globulins
Albumin
A comprehensive metabolic panel (CMP) consists of which group of tests?
Albumin, glucose, BUN, creatinine, sodium, potassium, chloride, CO2, AST, ALT, alkaline phosphatase (ALP), total protein, total bilirubin, calcium
What is the most commonly abused substance in the US?
Alcohol
Which clinical situation is GGT elevation most often associated with?
Alcohol consumption
What is the effect of aging with the hormones of the endocrine system?
Aldosterone decreases and norepinephrine increases
Pernicious anemia refers to cobalamin deficiency that results from a lack of what?
Intrinsic factor (IF)
Which of the following blood tests is used to determine acute pancreatitis? Acid phosphatase Uric acid Amylase Alkaline phosphatase (ALP)
Amylase
Assaying of what two enzymes increases diagnostic sensitivity of pancreatitis?
Amylase and lipase
Hormonal variation throughout the menstrual cycle typically shows:
An abrupt rise in luteinizing hormone (LH) 3-36 hours prior to ovulation
What is the drug disopyramide?
An antiarrhythmic agent
Which of the following parameters, according to the American Heart Association (AHA), is not included in the diagnosis of the presence of the metabolic syndrome in adults? An elevated waist circumference. An elevated triglyceride level. An elevated fasting glucose. An elevated HDL.
An elevated HDL
Which of the following apolipoproteins contributes the greatest mass to the structure of high-density lipoprotein (HDL)? Apo A Apo B Apo C Apo G
Apo A
Which of the following is considered to be the most specific marker for adverse ventricular remodeling or volume overload of the heart? CKMB Troponin Myoglobin BNP
BNP
What is true for a protein with an isoelectric point (pI) of 7.0?
At pH < 7.0, this protein will be positively charged
Which of the following tests should be collected in serum gel tube and goes to the chemistry department? BUN Zinc White blood cell (WBC) count Reticulocyte count
BUN
A lipid panel consists of what tests?
Cholesterol, lipoprotein, HDL, triglycerides
A patient is seen in the ER for abdominal pain and jaundice (yellowing of the skin and sclera). A quick urinalysis is performed and it is noted there is an increase in urine urobilinogen. All of the following are likely causes EXCEPT: Hepatitis Hemolytic episode Cholelithiasis Chronic liver disease
Cholelithiasis
Which lipid does not serve as a source of fuel, but can be converted to steroid hormones?
Cholesterol
What does a broad based increase in the gamma band of an SPE usually indicate?
Chronic inflammation
Which type of lipoprotein is the least dense?
Chylomicrons
What is another name for vitamin B12?
Cobalamin
Which one of the following serum constituents is increased following strenuous exercise? Creatinine Total lipids Sodium Iron
Creatinine
Where will elevated levels of conjugated bilirubin be seen?
Crigler-Najjar syndrome, erythroblastosis fetalis, transfusion reactions
A patient with truncal obesity, hypertension, a ruddy/striated complexion, and mood swings has multiple elevated glucose values. A fasting ACTH sample is also elevated. The physician orders a dexamathasone test, which shows an elevated cortisol level (no suppression). What is the most likely cause of the patient's values and symptoms?
Cushing Syndrome
A patient in renal failure is seen for blood work. What would you expect the serum calcium and phosphorous levels to be in this patient?
Decreased calcium but increased phosphorous levels (Damaged kidneys cannot complete the second hydroxylation of vitamin D to its active form of 1,25-hydroxy vitamin D. Therefore, vitamin D is not active and cannot increase calcium levels in the blood. Damaged kidneys also cannot absorb calcium and cannot excrete phosphorous.)
Recently the American Diabetes Association (ADA) recommended which values to correlate with hemoglobin A1C (HbA1C) as a further indicator of glycemic control?
Estimated average glucose
Which component of antifreeze can cause severe renal tubular damage along with similar effects of alcohol poisoning?
Ethylene glycol
In hemoglobin synthesis, which enzyme is responsible for adding iron in the last step?
Ferrochelatase
All of the following statements about fluorometry are true EXCEPT: Fluorometry is more sensitive than spectrophotometry. Both excitation and emission spectra are characteristics of the analyte. Fluorescence is indirectly proportional to the analyte being measured. Fluorometers typically utilize monochromators or optical fibers.
Fluorescence is indirectly proportional to the analyte being measured.
Regarding therapeutic drug monitoring, when should a specimen for a trough level be collected?
Immediately prior to the next dose
What is the most common technique used by clinical laboratories for therapeutic drug monitoring?
Immunoassay
What method may be employed to definitively identify Bence-Jones proteins?
Immunoelectrophoresis
A 46-year-old known alcoholic with liver damage is brought in the ER unconscious would expect his lipid values to be affected in what way?
Increased
The results which would be MOST consistent with macro-amylasemia are:
Increased serum amylase and normal to low urine amylase
Glucose is considered an aldose because:
It contains a terminal carbonyl group, called an aldehyde group
Why might serum ferritin (SF) alone be considered a less than optimal screening test for hereditary hemochromatosis (HH)?
It is an acute phase reactant that is frequently elevated in a variety of clinical conditions
When is a trough blood sample for therapeutic drug monitoring usually obtained?
Just before the next scheduled dose.
From the groups of analytes below, which set would most likely be INCREASED in a type 1 diabetic patient in crisis? Insulin and blood glucose Insulin and ketone bodies Ketone bodies and blood glucose Ketone bodies and blood pH
Ketone bodies and blood glucose
Which term describes the dose of the drug in which 50% of the individuals will result in mortality?
LD50
Which type of lipoprotein transports the MAJORITY of cholesterol to cells for steroid hormone synthesis or cell membrane incorporation? Chylomicrons VLDL LDL HDL
LDL
Increased levels of what lipid indicate an increased risk for cardiovascular disease?
LDL-C
Which medication is primarily used in the treatment of bipolar disorder?
Lithium
Vitamin D is formed in the skin and hydroxylated in two places before it is in its active form of 1,25-dyhydroxy vitamin D. Where are the sites of hydroxylation?
Liver and kidneys, respectively
Isoenzymes of CK include all of the following except: MB MM MBM BB
MBM
Samples for what tests are not recommended by CLSI to be transported through the hospital's pneumatic tube system?
Potassium, plasma hemoglobin, acid phosphatase, and lactate dehydrogenase
Which cardiac marker will be elevated FIRST if a patient has a myocardial infarction (MI)?
Myoglobin (peaks at about 2-4 hours after an MI)
What coenzyme does LD use when converting lactate to pyruvate?
NAD+
Can you use an alcohol wipe to cleanse the venipuncture site prior to obtaining a sample for ethanol?
No. The alcohol can interfere with the levels of ethanol and cause falsely-elevated levels.
The American Diabetes Association (ADA) recommends performing routine oral glucose tolerance test (OGTT):
OGTT use is discouraged for routine use
Human chorionic gonadotropin (hCG) is used in the determination of:
Pregnancy
What provides the normal viscosity of synovial fluid?
Polymerization of hyaluronic acid
Elevated conjugated bilirubin levels are seen in what conditions?
Posthepatic jaundice (such as biliary obstruction)
The lecithin/sphingomyelin (L/S) ratio determination of amniotic fluid is useful in assessing the probability of:
Respiratory distress syndrome (> 2.0 optimal)
What is gastrin's role in digestion?
Stimulates gastric acid-HCl secretion
Deviations from Beer's Law are caused by:
Stray light
When collecting a urine specimen for workplace drug testing, what usually indicates a specimen has been tampered with?
The specific gravity test result is less than 1.003 (indicates dilution with water)
A serum specimen for potassium testing is collected in a red top tube without a gel separator barrier. If testing is delayed by a few hours, how should the specimen be handled?
The specimen should be centrifuged as soon as it is clotted and serum should be transferred to another tube.
What is the drug primidone used for?
To control seizures (it's a barbiturate)
Mrs. Jones, a diabetic, is admitted to the hospital on November 25th. It appears that she has had an AMI but did not feel the severe chest pain because of diabetic neuropathy. She has not felt well since November 20th and her physician believes she possibly had an AMI on November 20th. Assuming that the infarct was uncomplicated, which of the following cardiac biomarkers would most likely still be elevated and would assist in an AMI diagnosis? Myoglobin CK-MB Troponin T All of the above
Troponin T
Normal adult hemoglobin A is composed of:
Two alpha and two beta chains
A reaction is in _________ kinetics when the reaction rate depends only on enzyme concentration.
Zero order
Follicle stimulating hormone (FSH) is produced by:
pituitary
Which of the following condition(s) would an increased serum osmolality be an expected finding? Dehydration and diabetes insipidus Hyponatremia and dehydration Increased arginine vasopressin hormone (AVP, formerly ADH) secretion and hyponatremia AVP and diabetes insipidus
Dehydration and diabetes insipidus
Total iron binding capacity (TIBC) measures the serum iron transporting capacity of:
transferrin
