exam 3, clin chem

Myoglobin is a good cardiac marker because it: -Doesn't diffuse into the blood at all when cardiac tissue dies. -Is an extremely large protein and therefore does not diffuse into the blood very easily. -Diffuses into the blood more slowly than CK-MB. -Diffuses into the blood more quickly than CK-MB.

Diffuses into the blood more quickly than CK-MB.

Which of the following is a recognized clinical feature of hypercalcemia? Muscle tetany Muscle weakness Dementia Mental retardation

Muscle weakness

Conditions linked to age-related bone loss include all of the following EXCEPT: malabsorption alcohol abuse hypoparathyroidism inactivity

hypoparathyroidism

Which of the following forms of calcium is biologically active: Protein-bound calcium Non-ionized calcium Calcium carbonate Free ionized calcium

Free ionized calcium

What is the required oxidation state (valence) of iron that enables it to bind to a chromogen in most spectrophotometric assays? +2 -3 +1 +3

+2

Hemochromatosis is best described as which of the following? -A genetically related disorder in which the body accumulates excess amounts of iron. -A genetically related disorder in which the body develops an iron deficiency. -A disorder characterized by an accumulation of porphyrins in the blood. -A disorder characterized by an iron overload without associate tissue injury.

A genetically related disorder in which the body accumulates excess amounts of iron.

Ionized calcium is most commonly measured using which of the following method: Flame photometry Color complex formation between calcium and o-cresolphthalein Atomic absorption Calcium ion selective electrodes

Calcium ion selective electrodes

The following laboratory results are consistent with which of the following conditions? Urine PBG/ALA: PBG>ALA Urine porphyrins: Increased Fecal porphyrins: Normal Erythrocyte porphyrins: Normal Acute intermittent porphyria ALA-dehydratase deficient porphyria ALA-dehydratase deficient porphyria Hereditary coproporphyria

Acute intermittent porphyria

Which of the following enzymes would be best to aid in identifying hepatobiliary disease? Alkaline Phosphatase (ALP) Aspartate aminotransferase (AST) Alanine amino transferase (ALT) Ammonia

Alkaline Phosphatase (ALP)

Steady state of a drug is typically achieved after: Approximately two half-lives. The drug is completely absorbed from the gut. Approximately seven half-lives. The drug first begins to appear in the urine.

Approximately seven half-lives.

Which one of the following enzymes catalyzes the transfer of an amino group to alpha- ketoglutarate with the formation of oxaloacetate and glutamate? Alanine aminotransferase (ALT) Aspartate aminotransferase (AST) Alkaline phosphatase (ALP) 5'-Nucleotidase (NTP)

Aspartate aminotransferase (AST)

A cardiac marker that increases progressively with increasing severity of disease and is not increased (or decreased) in conditions that mimic congestive heart failure is: B-type natriuretic peptide. troponin I. . CK-2. myoglobin.

B-type natriuretic peptide.

Elevation in conjugated bilirubin is most likely to be found in which of the following conditions: Transfusion reactions Erythroblastosis fetalis Cirrhosis of the liver Biliary obstruction

Biliary obstruction

A physician orders several laboratory tests on a 55-year-old male patient who is complaining of generalized (all-over) pain, stiffness, fatigue, and headaches. Based on the following serum test results, what is the most likely diagnosis: ALP—significantly increased, GGT— normal? Biliary obstruction Cirrhosis Primary metastatic liver cancer Bone disease

Bone disease

All of the following are sources of serum alkaline phosphatase except: Liver Placenta Brain Intestine

Brain

The marker for colorectal and pancreatic carcinoma is: CA 19-9. CA 15-3. CA 27-29. CA-125.

CA 19-9.

The most common cause of chronic pancreatitis is: Pregnancy Gall stone obstruction. Chronic alcohol abuse. Mumps.

Chronic alcohol abuse.

Which statement about iron methodology is true? -Colorimetric methods measure binding of Fe2+ to a ligand such as ferrozine. -Atomic absorption is the method of choice for measurement of serum Fe. -Serum Fe can be measured by potentiometry. -Interference from Hgb can be corrected by a serum blank.

Colorimetric methods measure binding of Fe2+ to a ligand such as ferrozine.

Which of the following fractions of bilirubin is water- soluble and reacts with a diazo reagent without the addition of an accelerator? Unconjugated bilirubin Conjugated bilirubin Total bilirubin Indirect bilirubin

Conjugated bilirubin

Pseudohypoparathyroidism is characterized by tissues that are resistant to the effects of circulating levels of parathyroid hormone (PTH). Which one of the following sets of values presents expected laboratory findings in this disorder? -Calcium, phosphorus, and PTH within healthy reference intervals -Elevated calcium, decreased phosphorus, normal PTH -Decreased calcium, elevated phosphorus, elevated PTH -Elevated calcium, elevated phosphorus, decreased PTH

Decreased calcium, elevated phosphorus, elevated PTH

Which of the following conditions would result in elevations in primarily conjugated bilirubin? Crigler-Najjar syndrome Physiologic jaundice of the newborn Dubin-Johnson syndrome Gilbert's syndrome

Dubin-Johnson syndrome

Which one of the following specimen types and collection methods is best for laboratory assessment of brain natriuretic peptide (BNP) in the evaluation of congestive heart failure? -Serum in glass blood collection tubes only -Heparinized plasma in any type of blood collection tube -EDTA-anticoagulated whole blood or plasma in plastic blood collection tubes only -Urine in sterile collection container for analysis of BNP metabolites only

EDTA-anticoagulated whole blood or plasma in plastic blood collection tubes only

1,25 (OH)2 D is the best blood test for determining adequacy of vitamin D stores in the body. True False

False

What is the primary storage form of iron? Apotransferrin Myoglobin Ferritin Hemosiderin

Ferritin

Which of the following enzymes is the most sensitive indicator of liver damage associated with alcohol ingestion: ALT GGT AST LDH

GGT

Alkaline phosphatase activity is increased in all of the following conditions except: Gastritis Hyperparathyroidism Childhood Obstructive Jaundice

Gastritis

Atherosclerosis is described as: -Syndromes that encompass a continuum of clinical presentations ranging from unstable angina to non-Q-wave AMI. -A degenerative condition of the muscles. -Hardening of the arteries that occurs over a period of many years due in part to the abnormal accumulation of lipids. -An acute-phase reactant whose concentration in the blood rises dramatically in response to nonspecific inflammatory stimuli.

Hardening of the arteries that occurs over a period of many years due in part to the abnormal accumulation of lipids.

A patient presents with elevated levels of IgG anti-HAV (HAV: Hep A Virus) while levels of IgM anti-HAV are non-detectable. This patient is likely to: Have an acute infection of HAV Have a chronic infection of HAV Have an immunity to HAV Be a carrier of HAV

Have an immunity to HAV

Which of the following anticoagulants will not produce a significant effect on calcium levels in plasma: EDTA Heparin Oxalates Citrates

Heparin

Which form of hepatitis is caused by a DNA virus? Hepatitis D Hepatitis B Hepatitis A Hepatitis C

Hepatitis B

Complications of acute pancreatitis include all of the following EXCEPT: Adult respiratory distress syndrome. Hypotriglyceridemia. Pseudocyst formation Splenic varices.

Hypotriglyceridemia.

Insulin and C-peptide levels are important in diagnosing: Glucagonomas. Insulinomas. Somatostatinomas. Pancreatic neoplasms.

Insulinomas.

Why would high-sensitivity C-reactive protein (CRP) be an indicator of a potential myocardial infarction? -CRP levels rise in response to decreased ATP generation in the heart. -It is an acute phase reactant plasma protein that rises in response to inflammation and the atherosclerotic process. -It is a myocardial protein that regulates muscle contraction through interaction with myosin and actin. -It is an enzyme found in skeletal muscle and cardiac muscle that is released upon muscle damage.

It is an acute phase reactant plasma protein that rises in response to inflammation and the atherosclerotic process.

Which of the following represents the correct sequence for the rise and fall of myoglobin, CK-MB, and cTnI after an AMI? Myoglobin, CK-MB, cTnI cTnI, CK-MB, myoglobin CK-MB, myoglobin, cTnI CK-MB, cTnI, myoglobin

Myoglobin, CK-MB, cTnI

Which of the following compounds is an anticonvulsant used to control tonic-clonic (grand mal) seizures? Acetaminophen Phenytoin Lithium Carbamazepine

Phenytoin

Which of the following hormones may be decreased in the geriatric population? TSH Follicle-stimulating hormone Testosterone Luteinizing hormone

Testosterone

Which of the following conditions would be suggested by a marked rise in alkaline phosphatase, jaundice, a moderate rise in ALT, and a marked increase in conjugated bilirubin: Cardiovascular disease Hemolytic anemia. Post-hepatic obstruction Renal failure

Post-hepatic obstruction

The goal of therapeutic drug monitoring (TDM) is to: -Provide the patient with the least amount of drug to effect the best outcome -Provide the patient with the optimum dosage of drug to effect the best outcome -Provide the patient with the cheapest formulation of the drug to effect the best outcome. Provide the patient with the best estimate of a dosage of drug to effect the best outcome

Provide the patient with the optimum dosage of drug to effect the best outcome

Which of the following products are formed from the forward reaction catalyzed by ALT? Pyruvate and glutamate Aspartate and alanine Oxaloacetate and glutamate Alanine and alpha ketoglutarate

Pyruvate and glutamate

Which of the following is an advantage of POCT for cardiac biomarkers? Rapid identification of AMI Delay in risk stratification of an AMI Delay in rule-out of an AMI Increased turn-around time for analysis

Rapid identification of AMI

The gold standard for evaluating pancreatic exocrine function is: Secretin/cholecystokinin. Pancreatic elastase. Fecal fat. Insulin.

Secretin/cholecystokinin.

Total iron binding capacity (TIBC) is equal to: -The sum of the serum iron and serum ferritin. -The sum of the serum transferrin and transferrin saturation. -The sum of the serum iron and unsaturated iron binding capacity (UIBC). -Serum iron minus unsaturated iron binding capacity (UIBC).

The sum of the serum iron and unsaturated iron binding capacity (UIBC).

Match the correct normal value in the blood of adults with the analyte listed: Total Bilirubin ALT Serum Phosphate Ionized (Free) Calcium Alkaline Phosphatase

Total Bilirubin: 0.2-1.0 mg/dL ALT: <45IU/L(males); <34IU/L (females) Serum Phosphate: 2.5-4.5 mg/dL Ionized (Free) Calcium: 4.6-5.3 mg/dL Alkaline Phosphatase: 53-128 IU/L (males); 42-98 IU/L (females)

The following analytes decrease with age EXCEPT: Total protein Creatinine clearance Total cholesterol Albumin

Total cholesterol

Which one of the following cardiac biomarkers is elevated about 50 times the upper limit of normal at 24 hours after onset of an acute myocardial infarction? Troponin CK-2 (CKMB) Myoglobin Total CK

Troponin

PTH and 1,25 (OH)2 D (vitamin D) are the principle hormones involved in the normal physiologic regulation of calcium homeostasis. True False

True

The most common cause of toxic hepatitis in North America leading to direct damage of hepatocytes is acetaminophen overdose. True False

True

Which of the following enzymes is responsible for the conjugation of bilirubin? UDP-glucuronyl transferase Alkaline Phosphatase Glutamate Dehydrogenase Leucine aminopeptidase

UDP-glucuronyl transferase

Which one of the following analytes is most useful in distinguishing primary from secondary hyperparathyroidism? Parathyroid hormone Serum calcium Vitamin D Serum phosphorus

Vitamin D

Bilirubin that is attached to albumin before it is transported across the hepatocyte membrane is called: indirect bilirubin direct bilirubin jaundice urobilinogen

indirect bilirubin

Specimen requirements for assessing free calcium using ion-selective electrode methodology include: heparinized whole blood. heparinized plasma. serum. all of the above.

all of the above.

An individual has the following laboratory test results: increased serum calcium, decreased serum phosphorus, increased parathyroid hormone. This individual most likely has: hyperparathyroidism hypoparathyroidism hyperthyroidism renal failure

hyperparathyroidism

Laboratory measurements for brain natriuretic peptide (BNP) be reported in: millimoles/liter. grams/deciliter. nanograms/liter picomoles/milliliter.

nanograms/liter

A 10-year-old girl visits her pediatrician with the complaint of bone pain. Following enzyme studies, these results were obtained: ALP 3.5 higher than upper reference limit; NTP (5'Nucleotidase) normal. These results are consistent with a diagnosis of: hepatobiliary disease. normal bone growth. viral hepatitis. bone cancer.

normal bone growth.

In bone: -calcium is complexed with bicarbonate. -the collagen component is type II collagen. -osteoclasts are responsible for bone formation. -osteoblasts are the bone-forming cells.

osteoblasts are the bone-forming cells.

The primary physiological regulator of parathyroid hormone (PTH) synthesis and secretion is: -PTH releasing hormone from the pituitary gland. -the concentration of free calcium in blood or extracellular fluid. -the concentration of PTH in blood. -PTH stimulating hormone.

the concentration of free calcium in blood or extracellular fluid.