Chem2
A patient has a Calcium of 3.2 mg/dl and a Potassium of 9.4. The tech checked the tube. It is an unhemolysed serum separator tube. What is the most likely cause of these results.
blood was transferred from a lavender top tube
Which isoenzyme of creatine kinase (CK) is primarily found in cardiac muscle?
cK-MB
A physician calls the laboratory and asks what lab tests should be requested to assess the acid-base balance function of a patient's renal system. You reply:S
erum bicarbonate and blood pH
A low-salt diet, low blood pressure, and diuretics would cause the following results:
increased renin, increased aldosterone, hypernatremia, Hypokalemia
A physician has ordered a hepatic on a patient. Which of the following test would you expect to see?A
lanine aminotransferase/ALT
Which of the following forms of the Henderson Hasselbalch equation is (are) correct?
pH = 6.1 + log HCO3/H2CO3 and pH = pKa + log HCO3/H2CO3
Upon receiving an arterial specimen for blood gases in the laboratory, you observe that it was not maintained under strict anaerobic conditions. You refuse to analyze the specimen. You base your decision on the premise that the following parameters have been altered:
pH increased, pCO2 decreased, pO2 increased
In addition to pancreatitis, an increase in serum lipase activity may be observed in:
renal insufficiency
Which of the following conditions is associated with hypophosphatemia?
rickets
Which cardiac marker is elevated for the longest period after myocardial infarction (MI)?T
roponin T
Violation of the 2-2S, 4-1S or 10x Westgard rules is a strong indication of _________.
systematic error
Does NOT influence the serum calcium concentration:
tyrosine
Which of the following results would be the most consistent with high risk for coronary heart disease?2
0 mg/dL HDL cholesterol and 250 mg/dL total cholesterol
A solution contains 4.5 grams of BaCl2 in 400 mL. What is the normality? (mw = 208)
0.11
The lipid: protein ratio of HDL is:5
0:50
The tourniquet should be left on no more then ___________ or _____________ will be elevated.
1 min, potassium and total protein
A serum specimen for glucose measurement was allowed to stand unseparated on the clot for 6 hours at room temperature before testing. If the original glucose concentration was 200 mg/dL, what approximate results would be expected after 3 hours?
160 mg/dL
A creatinine clearance is done on a patient with the following results: serum creatinine, 0.6 mg/dL; urine creatinine, 102 mg/dL; urine volume, 1650 mL/24 hours; body surface area, 1.93 sq m. This patient's creatinine clearance, corrected for body surface area, is:
175 mL/min
Convert 10 mg/dL of calcium to mmole/L. (mw = 40)
2.5
A patient sample for uric acid gave an absorbance reading of 0.4; the 50 mg/dL standard used in the test gave an absorbance reading of 0.1. What is the concentration of uric acid in the patient's sample in grams per deciliter?
200
How many millimoles of NaCl are contained in 300 mL of a 4M solution? (mw = 58.5)1
200
What is the normal ration of bicarbonate to dissolved carbon dioxide in arterial blood?
20:1
A patient brought to the emergency room has the following laboratory results: Sodium = 140 mmol/L Glucose = 80 mg/dLBUN = 6.0 mg/dL Glucose = 80 mg/dLBUN = 6.0 mg/dL Osmolality = 316 mOsm/Kg H2O The calculated osmolality on this patient using the Weisberg formula is:
286
Serum glucose determinations are done on samples from a control pool each day for 30 days. Quality control statistics are then calculated. The mean is 100 mg/dL and the standard deviation is 4 mg/dL. These statistics are used to label a quality control chart for the mean and +2 SD. Samples from the same control pool are then assayed each day along with patient samples, and control results are plotted on the chart. Results for the first 10 days are as follows:Day Result1 962 973 954 1075 1066 1077 898 1039 10610 105The coefficient of variation for these statistics is:
4%
How many milliliters of 0.5N NaOH are required to make 100 milliliters of 0.2N NaOH?
40
What is the percentage of serum calcium that is ionized (Ca1)?
45%
If a drug has a half-life of 7 hours, how many doses given at 7-hour intervals does it usually take to achieve a steady-state level?
5
Which of the following best represents the reference (normal) range for arterial pH?
7.35-7.45
As a screening test for Cushing's syndrome, the physician wishes to see whether a patient exhibits normal diurnal rhythm of his cortisol secretion. At what time should the specimens be drawn for plasma cortisol determination? (Assume a daytime work schedule for the patient.)
8 AM, 8 PM
Serum glucose determinations are done on samples from a control pool each day for 30 days. Quality control statistics are then calculated. The mean is 100 mg/dL and the standard deviation is 4 mg/dL. These statistics are used to label a quality control chart for the mean and +2 SD. Samples from the same control pool are then assayed each day along with patient samples, and control results are plotted on the chart. Results for the first 10 days are as follows: Day Result 1 962 973 954 1075 1066 1077 898 1039 10610 105 Using 95% confidence limits means that 95% of the control values would fall between:
92 and 108
One cause for a DECREASED "anion gap" is:
A decrease in albumin
Which of the following is the best analyte to monitor for recurrence of ovarian cancer?C
A-125
Which two liver enzymes are seen elevated in hepatobiliary disease?
ALP and GGT
A creatinine clearance is done on a patient with the following results: serum creatinine, 0.6 mg/dL; urine creatinine, 102 mg/dL; urine volume, 1650 mL/24 hours; body surface area, 1.93 sq m. Based on the information from calculations above, which of the following is the best interpretation of this patient's creatinine clearance results?
Above normal
In absorption spectrophotometry:
Absorbance is directly proportional to concentration
In a spectrophotometric determination, which one of the following is the formula for calculating the absorbance of a solution?
Absorptivity x light path in cm x concentration
Which term would represent a blood pH of less than 7.35?
Acidosis
Type 1 diabetes mellitus may be described by all of the following EXCEPT:
Adult-onset type
Which of the following is the major mineralocorticoid?
Aldosterone
Which of the following conditions is associated with hypokalemia?
Alkalosis
Deficiency in homogentisate oxidase
Alkaptonuria
A moderately hemolyzed tube is drawn in the ER. Which of the following tests will be affected? A. Potassium B. Phosphorus C. Magnesium D. All of these
All of these
A tech draws a glucose in a sodium fluoride tube. The doctor later wants to add additional tests. Which test(s) should not be performed? A. Calcium B. BUN C. Magnesium D. All of the these
All of these
The acute phase reactant protein that also inhibits proteolysis and has the highest concentration within its globulin fraction is:
Alpha1-antitrypsin
Enzymes associated with acute pancreatitis are:
Amylase and lipase
The glucose value of a NORMAL 2-hour post-prandial serum specimen, as compared to the reference range for a fasting serum glucose, should be:
Approximately the same as the normal fasting glucose level
The major non-glucose-reducing substance present in serum is:
Ascorbic acid
Cocaine is metabolized to:
Benzoylecgonine
Hypernatremia commonly occurs in:
Burns and excessive sweating without water intake
When myocardial infarction occurs, the first enzyme to reach peak elevation is:
CK
The federal regulation most cited and the one with which most laboratories must comply when implementing a POCT system is the:
CLIA
Random-access analysis is a type of analysis in which a specimen:
Can be analyzed by any available process without regard to the initial order of specimens
Sandy Jones comes in to see her doctor right after lunch. He is concerned with how high her glucose readings have been. He sends her to the lab for glucose and an A1C. She tells the lab tech that she just checked her blood sugar with her meter two minutes ago. It was 356 mg/dL. The tech draws her blood and tests the glucose level. The result is reported as 329mg/dL. What is the most likely reason for this difference?
Capillary blood glucose is higher the venous after a meal
The parent substance in the biosynthesis of androgens and estrogens is:
Cholesterol
Anemia, hyperphosphatemia, hypocalcemia, and ongoing azotemia are most indicative of:
Chronic renal failure
CEA is most commonly associated with:
Colon cancer
Given the following lab results, what is the most likely cause of this patient's BUN?BUN 45 mg/dLCreatinine 1.8 mg/dLUric Acid 7 mg/dLpH 7.22pCO2 74.4 mm HgpO2 32.8 mm HgO2 sat. 51.3%
Congestive heart failure
Which of the following diseases is characterized by primary hyperaldosteronism caused by adrenal adenoma, carcinoma, or hyperplasia?
Conn's disease
Biotransformation or metabolism of a drug refers to the:
Conversion of drug to active or inactive compounds
Pituitary secretion of adrenocorticotropic hormone (ACTH) is inhibited by elevated levels of:
Cortisol
Peptide bonds of proteins bind with _________ ions of biuret reagent to produce a colored product.
Cupric
Increased excretion of cysteine due to defect in renal absorption
Cystinuria
Which of the following is an effect of increased parathyroid hormone secretion?
Decreased blood calcium levels, increased renal reabsorption of phosphate, decreased bone resorption, and increased intestinal absorption of calcium
Which of the following is likely to occur first in iron deficiency anemia?
Decreased serum ferritin
A plasma specimen from a hospital patient is analyzed on an osmometer and reported as 400 mOsm/Kg. What is the most likely effect on this patient's water distribution in the tissues?
Dehydration
Increased serum albumin concentrations are seen in which of the following conditions?
Dehydration
Which of the following condition is associated with hypernatremia?
Diabetes insipidus
Porphobilinogen may be differentiated from urobilinogen in urine by:
Difference in chloroform solubility of Ehrlich's aldehyde derivatives
A cardiac glycoside that is used in the treatment of congenital heart failure and arrhythmias by increasing the force and velocity of myocardial contraction is:
Digoxin
Hyperkalemia may be seen in all the following EXCEPT: A. Primary adrenal insufficiency, dehydration, and diabetes insipidus B. Primary adrenal insufficiency and diabetes insipidus C. Dehydration and diuretic therapy D. Diuretic therapy only E. Primary adrenal insufficiency, dehydration, diabetes insipidus, and diuretic therapy
Diuretic therapy only
Which of the following best describes the correct collection and handling conditions for a blood ammonia measurement?
Draw heparin tube, keep on ice, test immediately
Most standards organizations recognize _______ as the anticoagulant of choice for blood cell counts.
EDTA
A 21-year-old man with nausea, vomiting, and jaundice has the following laboratory findings: Total serum bilirubin 8.5 mg/dL (normal 0-1.0 mg/dL) Direct serum bilirubin 6.1 mg/dL (normal 0-0.5 mg/dL) Urine urobilinogen Increased Urine bilirubin Positive AST 200 U/L (normal 0-50 U/L) ALP 160 U/L (nor mal 0-150 U/L)
Early Hepatitis
When a purified enzyme is used as a reagent, such as urease in the measurement of urea, the enzyme must be ___________________ concentration so that the reaction follows_________________ kinetics.
Excess; first
Bioavailability of a drug refers to the:
Extent and rate at which the active drug reaches target tissues
True or false? Peak drug levels in the blood are usually measured to determine the drug's efficacy.
False
True or false? Serum urea levels are less affected by diet and metabolism than are serum creatinine levels.
False
True or false? The main function of antidiuretic hormone is to increase the reabsorption of sodium and increase the secretion of potassium.
False
The American Diabetes Association recommends which of the following for screening a diagnosis of Diabetes mellitus?
Fasting plasma glucose
Which of the following enzymes detects very early changes in liver cell damage?
GGT
The "gold standard" confirmation method for positive drug screens is:
Gas chromatography/mass spectrometry
The formation of glucose from compounds like fatty acids, glycerol, and amino acids is called:
Gluconeogenesis
A diabetic patient is prescribed a daily regimen of insulin. Which of the following laboratory procedures would be of most value in determining the degree of glucose control over a 2-month period?
Glycated hemoglobin
Which of the following is a tropic (stimulating) hormone?
Growth hormone
The lipoprotein that contains the greatest amount of protein is called:
HDL
In the PCR method, how is denaturation accomplished?
Heat
The only acceptable anticoagulant for a calcium determination is:
Heparin
A patient is admitted to the hospital with intense chest pains. The patient's primary care physician requests that the emergency room doctor order several tests, including a lipid profile with cholesterol fractionation. The patient's results are as follows: Total Cholesterol = 400 mg/dL Triglycerides = 300 mg/dL Cholesterol = 100 mg/dL LP Electrophoresis - pending This patient's LDL cholesterol is:
High
A patient is admitted to the emergency room in a state of metabolic alkalosis. Which of the following would most likely be consistent with this diagnosis?
High pCO2, increased HCO3
In rickets patients, typical findings include all of the following EXCEPT: A. High serum phosphate B. High PTH C. Low serum calcium D. High alkaline phosphatase
High serum phosphate
A patient has the following test results: increased serum calcium levels, decreased serum phosphorus levels, increased levels of parathyroid hormone. This patient most likely has:
Hyperparathyroidism
Which of the following is the primary mechanism of compensation for metabolic acidosis?
Hyperventilation
In a patient with suspected primary hyperthyroidism associated with Graves' disease, one would expect the following laboratory serum results: T4 _________, TSH _________.
Increased, decreased
Unconjugated bilirubin is _________________ and conjugated bilirubin is____________________.
Indirect and water insoluble, Direct and water soluble
Which patient results indicate the highest risk of brain damage:
Indirect bilirubin: 10. 2 mg/dL
Calcitonin:
Inhibition of calcium reabsorption
Energy or frequency of light waves varies ____________ with the wavelength.
Inversely
POCT tests classified as waived by government standards include all of the following EXCEPT:
Ionized calcium
A patient presents to her primary care provider with the following test results: Serum Iron: 25 ug/dl TIBC: 516 ug/dl Serum Ferritin: 13 mg/dl
Iron Deficiency anemia
Blood specimens drawn early in the morning are recommended for measuring serum iron and TIBC because:
Iron exhibits a diurnal cyclic variation
Urea:
Is synthesized from CO2 and ammonia
An LD flip, in assessing a possible myocardial infarction, refers to:
LD1 > LD2
LD has five isoenzymes, which two are associated with liver disease and skeletal diseases?
LD4 (HMMM) and LD5(MMMM)
Which of the following enzymes has multiple molecular forms (isoenzymes) whose clinical significance is used in diagnosis?
Lactate dehydrogenase, creatine kinase, and alkaline phosphatase
The Jaffe alkaline picrate reaction for creatinine can be made more specific for creatinine with the use of:
Lloyd's reagent
A patient presents with Addison's disease. Serum sodium and potassium analyses are done. The results would reveal:
Low sodium, high potassium levels
Deficiency of branch-chained keto acid decarboxylase
Maple syrup urine disease
What is the gold standard methodology for Toxicology testing?
Mass Spectrometry
LH:
Maturation of follicles, ovulation, production of estrogen, progesterone and testosterone
Tests of pancreatic exocrine function include:
Measurement of serum amylase and lipase activity
Heroin is synthesized from:
Morphine
Triiodothyronine:
Mostly formed from the deiodination of t4, responsible for metabolism, growth and development
A patient comes in to the clinic complaining of chest pains. The total CK was extremely elevated. The physician orders CK isoenzymes along with other cardiac markers. Based on the CK isoenzymes results listed below: CK BB normal CK MB normal CKMM elevated What would you suspect is wrong with this patient?
Muscular dystrophy
AFP and CEA are examples of which type of tumor marker?
Oncofetal antigen
The term below that is related to the ability of plasma proteins to maintain plasma water volume is:
Oncotic pressure
Interpret the following results: Cholesterol: 178 mg/dl Triglycerides: 233 mg/dl HDL: 52 mg/dl LDL: 79.4 mg/dL
Only the Triglyceride is abnormal
Creatinine is formed from the:
Oxidation of creatine
H2CO3 is regulated by the lungs and is equal to:
PCO2 X 0.03
The three hormones that regulate serum calcium are:
PTH, vitamin D, and calcitonin
Progesterone:
Parallels activity of the corpus luteum by rapidly increasing following ovulation and then abruptly falling to initial low concentrations prior to the onset of menstruation
Calcium concentration in the serum is regulated endogenously by:
Parathyroid hormone
When therapeutic failure of aminoglycoside levels is suspected, one should draw a _________ serum drug level for measurement.
Peak
Which condition produces the highest elevation of serum lactate dehydrogenase?
Pernicious anemia
Deficiency of phenylalanine hydroxylase
Phenylketonuria
An anticonvulsant used to control tonic-clonic (grand mal) seizures is:
Phenytoin
The TRH (thyrotropin releasing hormone) stimulation test is useful in differentiating hypothalamic hypothyroidism from:
Pituitary hypothyroidism
A compound that may be detected by observing its rose-red color in the aqueous layer of the Watson-Schwartz test is:
Porphobilinogen
A patient comes into the ER with the following results: Total bilirubin 15.2 mg/dL Direct Bilirubin 3.2 mg/dL Urine bilirubin Positive Feces Clay colored What condition is most likely?
Posthepatic Jaundice
A patient comes into the outpatient clinic with the following results: Total bilirubin 15.2 mg/dL Direct Bilirubin 0.2 mg/dL Urine bilirubin Negative Feces Dark brown What condition is most likely?
Prehepatic jaundice
Thyroxine:
Principle thyroid hormone responsible for metabolism, growth and development
TSH:
Production of T3 and T4 by thyroid
ACTH:
Production of adrenocortical hormones by adrenal cortex
Tubes that contain a gel serum separator should not be used for:
Progesterone testing
Pituitary adenomas that secrete _______ are by far the most common form of hyperpituitarism.
Prolactin
Growth hormone:
Protein synthesis, cell growth and division
What is the first feature of nephrotic syndrome that results in manifestation of the other four classic signs?
Proteinuria
Production of bilirubin occurs in the __________, and conjugation of bilirubin to glucuronide occurs in the _____________.
RES; liver
A chemistry analyzer that can perform multiple analyses on a single specimen during one run is referred to as a:
Random access analyzer
Aldosterone:
Reabsorption of sodium in the renal tubules
ADH:
Reabsorption of water in distal renal tubules
Parathyroid hormone:
Regulation of calcium and phosphorus
Which of the following conditions will cause an increased anion gap?
Renal failure
The following laboratory results were obtained: Sodium 136 mEq/L pH 7.32 Potassium 4.4 mEq/L pCO2 79 mm Hg Chloride 92 mEq/L Bicarbonate 40 mEq/L These results are most compatible with:
Respiratory acidosis
A low plasma osmolality and low sodium would be expected in a patient with:
SIADH
Interpret the following results on a young female that is complaining of extreme fatigue and weight gain. T4- Decreased T3-Decreased FT4-Decreased TSH-Decreased
Secondary Hypothyroidism
Serum glucose determinations are done on samples from a control pool each day for 30 days. Quality control statistics are then calculated. The mean is 100 mg/dL and the standard deviation is 4 mg/dL. These statistics are used to label a quality control chart for the mean and +2 SD. Samples from the same control pool are then assayed each day along with patient samples, and control results are plotted on the chart. Results for the first 10 days are as follows: Day Result1 962 973 954 1075 1066 1077 898 1039 10610 105 On day 4 above, the light source was changed in the spectrophotometer used for this procedure. The results seen in the quality control after that day are called:
Shift
The greatest tissue source of CK is:
Skeletal muscle
A major extracellular cation that contributes to about half of plasma's osmolality. It plays a central role in maintaining water distributions and osmotic pressure.
Sodium
Which electrolyte level best correlates with plasma osmolality?
Sodium
The preferred collection tube for preservation of glucose is:
Sodium fluoride
Which technique is used to detect DNA containing a specific base sequence by applying a labeled probe to DNA bands immobilized onto nitrocellulose paper following electrophoresis?
Southern blot
A test's "negativity in the absence of the disease" is termed its:
Specificity
FSH:
Sperm and egg production
The coefficient of variation (CV) is:
Standard deviation expressed as % of the average of the values used to calculate the standard deviation
Myocardial infarction can produce a CK isoenzyme profile that is similar to:
Strenuous exercise
Which formula provides the best estimate of serum transferrin?
TIBC (µg/dL) x 0.70 = transferrin in mg/dL
The major fraction of organic iodine circulating in the blood is:
Tetraiodothyronine
Urea is produced from:
The catabolism of proteins and amino acids
A drug that relaxes the smooth muscles of the bronchial passages is:
Theophylline
A two-year-old child with a decreased serum T4 is described as being somewhat dwarfed, stocky, and overweight and having coarse features. Of the following, the most informative additional laboratory test would be serum:
Thyroid-stimulating hormone (TSH)
Diurnal variation is a term that refers to:
Time of day of specimen collection
A patient is having blood work done for a routine physical. The patient had a large breakfast before coming in to the appointment. Which test would be most affected?
Triglycerides
Which MI marker is the most specific and sensitive and remains elevated for 14 days or more?
Troponin T
True or false? Chloride is the major extracellular anion in plasma.
True
True or false? Serum uric acid levels may be elevated in patients undergoing cancer chemotherapy.
True
A 55 year old, African American male presents to the physicians office. He is severally over weight. They physician orders a fasting glucose, urine glucose and an A1C, the results are as follows: Fasting glucose: 212 mg/dL A1C: 13.7% Urine glucose: positive What condition is the physician most lily suspecting?
Type 2 Diabetes Mellitus
Defect in fumarylacetoacetase
Tyrosinemia
The enzyme that conjugates bilirubin in the hepatocyte is:
UDP-glucuronyl transferase
A toxic condition involving a very high serum level of urea and creatinine accompanied by failure of the three main functions of the renal system is referred to as:
Uremia
Bilirubin is reduced to __________ in the small intestine.
Urobilinogen
Oxytocin:
Uterine concentrations during child birth
The FINAL metabolite of epinephrine that is measured in urine is:
Vanillylmandelic acid
Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) are both elevated in which of the following diseases
Viral hepatitis
Defect in enzyme tyrosine
albinism
Unconjugated bilirubin circulated in the bloodstream is bound to:
albumin
Parathyroid hormone and thyroid stimulating hormone are higher in the morning verses the evening.F
alse
