Lab Automation Benefits & Steps

MEDICAL LABORATORY SCIENCE 7. SUMMATIVE EXAM REVIEW QUESTIONS #18 + ANSWERS & RATIONALIZATIONS 1. 2. 3. 4. 5. 6. The major benefit(s) of laboratory automation is (are): a. Reduction in medical errors. b. Improved safety for laboratory staff. c. Faster turnaround time. d. All the above. → Benefits of automation ▪ Reduction of medical errors ▪ Reduced specimen sample volume ▪ Increased accuracy and precision (reduced coefficient of variation) ▪ Improved safety for laboratory staff (such as stopper removal or piercing) ▪ Faster turnaround time of results ▪ Partially alleviating the impending shortage of skilled laboratory staff Steps in automation designed to mimic manual techniques include: a. Pipetting of specimen b. Pipetting of reagents c. Measurement of chemical reactions d. All the above → The major steps designed by manufacturers to mimic manual techniques are as follows: ▪ Specimen collection and processing ▪ Specimen and reagent measurement and delivery ▪ Chemical reaction phase ▪ Measurement phase ▪ Signal processing and data handling Health indicators, except: a. Life expectancy b. Mortality c. Incidence or prevalence d. Injury rate → Health Indicator - measurable characteristic that describes the health of a population (e.g., life expectancy, mortality, disease incidence or prevalence, or other health states) Which of the following is objective? a. Pea-sized b. Rough c. 1 cm. length d. All of these → Subjective vs Objective ▪ Subjective: Based on personal opinion or interpretation ▪ Objective: Fact-based, MEASURABLE, and observable How would 6.32 be rounded off to one less decimal place? a. 6.32 b. 6.4 c. 7.0 d. 6.3 How would 15.57 be rounded off to one less decimal place? a. 15.6 b. 15.5 c. 16.0 d. 15.0 8. 9. 10. 11. 12. 13. 14. 15. How would 25.96 be rounded off to one less decimal place? a. 26.0 b. 25.9 c. 25.6 d. 26.96 Accuracy is defined as: a. How close results are to one another b. How close a test result is to the true value c. Specimen that is similar to patient’s blood; known concentration of constituent d. Comparison of an instrument measure or reading to known physical constant Precision is defined as: a. How close results are to one another → reproducibility b. How close a test result is to the true value c. Comparison of an instrument measure or reading to a known physical constant d. Measurement of a highly purified substance of known composition Calibration is defined as: a. How close results are to one another b. How close a test result is to the true value c. Specimen that is similar to patient’s blood; known concentration of constituent d. Comparison of an instrument measure or reading to a known physical constant Sensitivity is: a. Cases with a specific disease or condition that produce a positive result → truly positive b. Cases without a specific disease or condition that produce a negative result c. Cases with a specific disease or condition that produce a negative result d. Cases without a specific disease or condition that produce a positive result The standard deviation is: a. Equal to SD divided by the mean b. Measure of variability c. The same as the mean value d. An exact measurement of an analytic value Levey-Jennings plots: a. Show values on a chart b. Have three warning rules c. Have three mandatory rules d. All the above → Levey-Jennings chart can be constructed for each analytical method and each control based on the calculated mean and standard deviation. A procedure with minimal complexity, instrumentation, and personnel requirements so that the results can be quickly determined: a. Waived test b. Nonwaived test c. Definitive test d. Presumptive test Highly sensitive and specific test in which results can be used as legal evidence: a. Waived test b. Non-waived test c. Definitive test d. Presumptive test 1 16. Tests that are very simple or pose no reasonable risk of harm to the patient if the test is performed incorrectly: a. Waived test b. Nonwaived test c. Definitive test d. Reference or gold standard 17. Complex tests that require skill to perform and interpret and are therefore regulated: a. Waived test b. Nonwaived test c. Definitive test d. Reference or gold standard 18. Best available approximation of a true value, although not necessarily 100% accurate: a. Waived test b. Nonwaived test c. Definitive test d. Reference or gold standard 19. A nurse calls the laboratory technologist on duty asking about blood collection for the analysis of enzymes (AST, ALP, ALT, GGT, CK). Which of the following tubes would you suggest the technologist collect? a. Red top b. EDTA c. Oxalate d. Fluoride 20. A blood sample is left on a phlebotomy tray for 4.5 hours before it is delivered to the laboratory. Which group of tests could be performed? a. Glucose, Na, K, Cl, TCO2 b. Uric acid, BUN, creatinine c. Total and direct bilirubin d. CK, ALT, ALP, AST 21. Treatment by therapeutic phlebotomy: a. Aplastic anemia b. Iron deficiency anemia c. Hemochromatosis d. Hyperbilirubinemia 22. Formation of glucose-6-phosphate from noncarbohydrate sources: a. Glycolysis b. Glycogenolysis c. Glycogenesis d. Gluconeogenesis → Pathways Of Glucose Metabolism ▪ Glycolysis: metabolism of glucose molecule to pyruvate or lactate for production of energy ▪ Gluconeogenesis: formation of glucose-6phosphate from noncarbohydrate sources ▪ Glycogenolysis: breakdown of glycogen to glucose for use as energy ▪ Glycogenesis: conversion of glucose to glycogen for storage ▪ Lipogenesis: conversion of carbohydrates to fatty acids ▪ Lipolysis: decomposition of fat 23. Before an OGTT is performed, individuals should ingest at least ______ per day of carbohydrates for the ___ days preceding the test. a. 75 grams CHO per day for 2 days b. 100 grams CHO per day for 2 days c. 100 grams CHO per day for 3 days d. 150 grams CHO per day for 3 days 24. When preparing a patient for an oral glucose tolerance test (OGTT), which of the following conditions will lead to erroneous results? a. The patient remains ambulatory for 3 days prior to the test b. Carbohydrate intake is restricted to below 150 g/day for 3 days prior to test c. No food, coffee, tea, or smoking is allowed 8 hours before and during the test d. Administration of 75 g of glucose is given to an adult patient following a 10–12-hour fast 25. 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 → Low-Density Lipoprotein (LDL) is currently the only lipoprotein or lipid that is recommended for use by physicians for therapeutic lifestyle changes. 26. Which enzyme deficiency is most commonly associated with familial hypertriglyceridemia associated with fasting plasma chylomicrons (formerly type I hyperlipoproteinemia)? a. β Glucocerebrosidase deficiency b. Post–heparin-activated lipoprotein lipase deficiency c. Apo-B deficiency d. Apo-C-III deficiency e. Deficiency of capillary endothelial lipase is the most common cause of fasting chylomicronemia. This lipase is also known as post–heparin- activated lipase and apo C-II–activated lipase. 27. Most useful index for assessing severity of liver disease: a. Albumin b. Total protein c. Urea d. Creatinine 28. Important role in maintaining colloidal oncotic pressure and preventing edema: a. Albumin b. Prealbumin c. Transferrin d. Fibrinogen 29. Nutritional assessment with poor protein-caloric status is associated with: a. A decreased level of prealbumin b. A low level of γ-globulins c. An elevated ceruloplasmin concentration d. An increased level of α1-fetoprotein 2 30. All of the following migrate with the alpha2 globulins, EXCEPT: a. Alpha2-macroglobulin b. Ceruloplasmin c. Haptoglobin d. Transferrin → Protein migration: 31. The largest major nonimmunoglobulin protein in plasma: a. Alpha1-antitrypsin b. Alpha1-acid glycoprotein c. Alpha2-macroglobulin d. Transferrin 32. Diffuse but large elevation of gamma-globulins: a. Chronic liver disease b. Chronic inflammatory disease c. Hypoalbuminemia d. Nephrotic syndrome 33. Diffuse but small elevation of gamma-globulins: a. Chronic liver disease b. Chronic inflammatory disease c. Hypoalbuminemia d. Nephrotic syndrome e. Electrophoretic Patterns of Various Diseases 34. All of the following are true for nephrotic syndrome, except: a. Striking proteinuria b. Decreased in serum albumin and total protein c. Increased creatinine, BUN and uric acid d. None of these 35. True for glomerulonephritis: a. Elevated urine protein b. Increased serum creatinine and BUN c. RBCs and casts in urine d. All of these → Comparison of Kidney-Associated Diseases 36. To assure ammonia level result, the specimen should be: a. Incubated at 37 °C prior to testing b. Spun and separated immediately, tested as routine c. Spun, separated, iced and tested immediately d. Stored at room temperature until tested → Because of the false increase in ammonia levels caused by smoking, patients should be instructed to refrain from smoking for 8 hours before blood collection. 37. Which test is the most sensitive in detecting early monoclonal gammopathies? a. High-resolution serum protein electrophoresis b. Urinary electrophoresis for monoclonal light chains c. Capillary electrophoresis of serum and urine d. Serum-free light chain immunoassay → Immunonephelometric free light chain assays can detect monoclonal protein production before the mass is sufficient to cause a monoclonal spike on protein electrophoresis or capillary electrophoresis, but will be positive only in cases where monoclonal light chain production occurs. → Therefore, measurement of free light chains is recommended along with protein electrophoresis when testing for myeloma. 38. Which test is the most useful way to evaluate the response to treatment for multiple myeloma? a. Measure of total immunoglobulin b. Measurement of 24-hour urinary light chain concentration (Bence–Jones protein) c. Capillary electrophoresis of M-protein recurrence d. Measurement of serum-free light chain → Light chains have a shorter plasma half-life than intact Ig and therefore, the reduction in free light chain concentration is an earlier indicator of treatment effect than measurement of intact Ig. 39. Which of the following is a characteristic of conjugated bilirubin? a. It is water soluble b. It reacts more slowly than unconjugated bilirubin c. It is more stable than unconjugated bilirubin d. It has the same absorbance properties as unconjugated bilirubin 3 → Conjugated vs. Unconjugated Bilirubin 40. Gilbert’s syndrome: a. Bilirubin transport deficit b. Conjugation deficit c. Excretory deficit d. None of these 41. Crigler-Najjar syndrome: a. Bilirubin transport deficit b. Conjugation deficit c. Excretory deficit d. None of these 42. Overall capacity to transport bile: a. Serum bilirubin level b. Ratio of direct and total bilirubin c. Serum bile acids d. Urine urobilinogen 43. Capacity to conjugate bilirubin; quantity of hemoglobin turnover: a. Serum bilirubin level b. Ratio of direct and total bilirubin c. Serum bile acids d. Urine urobilinogen 44. Abnormality of bile duct epithelium: a. Serum bilirubin level b. Ratio of direct and total bilirubin c. Serum ALP and other “obstructive” enzymes d. Serum aminotransferase levels 45. Hepatocellular damage and necrosis: a. Serum bilirubin level b. Ratio of direct and total bilirubin c. Serum ALP and other “obstructive” enzymes d. Serum aminotransferase levels 46. For carbon dioxide determination, acidifying the sample: a. Converts the various forms of CO2 in plasma to gaseous CO2 by dilution with an acid buffer b. Prevents conversion of the various forms of CO2 in plasma to gaseous CO2 by dilution with an acid buffer c. Converts all CO2 and carbonic acid to HCO3− d. Prevents conversion of all CO2 and carbonic acid to HCO3− → Determination Of Carbon Dioxide: The first step in automated methods is acidification or alkalinization of the sample. ▪ Acidifying the sample converts the various forms of CO2 in plasma to gaseous CO2 by dilution with an acid buffer. ▪ Alkalinizing the sample converts all CO2 and carbonic acid to HCO3−. 47. What is the anticoagulant of choice for blood gas analysis? a. EDTA b. Heparin c. Sodium fluoride d. Citrate → Specimen Requirements For Blood Gas Analysis 1. Arterial blood is collected in a glass or plastic syringe. Capillary specimens can also be used (blood must be “arterialized”). 2. Lyophilized or liquid heparin is the preferred anticoagulant. 3. No air bubbles should exist in the sample because they lower the pCO2 value. 4. The specimen must be placed on ice and transported to the laboratory in 15 minutes at 4°C and tested immediately. Otherwise, pH values decrease, and pCO2 values increase. 5. Blood clots are unacceptable. 48. Which of the following tissues does not secrete steroid hormones? a. Ovaries b. Pituitary gland c. Testes d. Adrenal cortex 49. Which of the following is the most potent androgen? a. Androstenedione b. Dehydroepiandrosterone c. Androsterone d. Testosterone → Testosterone is the principal androgen hormone in the blood, and after puberty the testes secrete 4 to 10 mg daily and less than 5% is derived from adrenal precursors such as dehydroepiandrosterone (DHEA) and androstenedione. → Once inside a cell, testosterone is metabolized to one of two active metabolites: dihydrotestosterone (DHT) or estradiol → DHT binds to the androgen receptor with higher affinity and, thus, is a more potent metabolite as compared to testosterone. 50. Hormone that regulates synthesis and release of the thyroid hormones is produced in: a. Hypothalamus b. Anterior pituitary gland c. Posterior pituitary gland d. Thyroid 4