Practice BOC
In which of the following situations would a bone marrow aspirate and biopsy possibly be used as an aid for diagnosis?(Select all that apply)
Evaluation of anemia and thrombocytopenia Evaluation of cytopenias Diagnosis of leukemias Evaluation of fever of unknown origin (FUO)
True or False: Lymphocyte pleocytosis refers to a decreased number of lymphocytes in a CSF when compared to a normal sample.
FALSE
The 5' end of a DNA strand ends with a OH group.
False The 5' end of a DNA strand is distinguished by a phosphate while the 3' end is distinguished by a OH group.
What sero-marker is the first marker to become positive in Hepatitis B and is associated with the infective stage
HBs antigen
How long does it take for plasma concentrations to reach steady state when a patient's dose is given at intervals of the drug's half-life?
4-7 half-lives The time taken to reach the steady state is about five-seven times the half life of a drug.
Which of the following would be considered a normal cerebrospinal fluid glucose if the serum glucose is 70 mg/dl
45 mg/dl As a general rule, CSF glucose is about two thirds of the serum glucose measured in a normal adult.
This organism is found endemically on the New England seacoast. When seen in peripheral blood smears, it resembles a parasite of the genus Plasmodium. When an organism RESEMBLING malarial parasites is found in the peripheral blood, it is MOST probably:
Babesia
What is the MOST common infective agent to be transmitted through blood transfusion that results in morbidity and mortality?
Bacteria
3-year old girl was brought to the ER with a temperature of 103ºF, lethargy, and cervical rigidity. Three tubes of cloudy CSF were delivered to the Lab, and preliminary test results showed: WBC: 4,500/uL Differential: 88% neutrophils Glucose: 15 mg/dL 12% lymphocytes Protein: 140 mg/dL Gram stain: No organisms observed
Bacterial meningitis Due to the elevated white blood cell count along with a strong percentage of neutrophils, a bacterial
When is a trough blood sample for therapeutic drug monitoring usually obtained?
Just before the next scheduled dose
Which of the following microorganisms should be maintained as a stock culture to check for encapsulated unknowns?
Klebsiella pneumoniae Streptococcus pyogenes
Which of the following may cause a false positive bilirubin result on a urine chemical reagent strip?
Large doses of chloropromazine
What type of follow-up testing is recommended for a Speckled ANA pattern
Testing for antibodies to the extractable nuclear antigens (ENA)
Night blindness Beriberi Rickets Scurvy
Vitamin A Night blindness Thiamine Beriberi Vitamin D Rickets D Vitamin C Scurvy
A defect in which of the following factors causes impaired platelet adhesion and aggregation?
Von Willebrand factor
If Jka is showing dosage, how might reactions on an antibody panel appear?
Weaker if heterozygous for Jka and Jkb
The type of health-care occupational exposure with the greatest risk of HIV transmission is:
a percutaneous injury
Epstein-Barr: Rhabdovirus: Varicella-Zoster: Picornavirus:
Epstein-Barr: Infectious mononucleosis Rhabdovirus: Rabies Varicella-Zoster: Chicken pox Picornavirus: Polio
Rheumatic fever-
Antimyocardial antibodies
Wegener's granulomatosis
Antineutrophilic antibodies
Multiple flagella at two ends only
Amphilophotrichous
MOST of the carbon dioxide present in the blood is in the form of:
bicarbonate
That portion of an enzyme which is separated from its cofactor is called a(n
Apoenzyme
Cells seen in the microscopic examination of the urine of a 30 year old female which are smaller than RBC's but much the same shape are probably:
yeast cells
An average adult would excrete approximately what volume of urine per 24 hours:
1500 ml
Antenatal RhIg (1500 IU dose) is typically given at how many weeks gestation?
28
Troponin I is used frequently to assess acute myocardial infarctions (AMI). If a patient has experienced an AMI, at what point (approximately) will the troponin I begin to increase and how long will it stay increased?
3-6 hours, 5-10 days
A serum sample is received in the clinical chemistry department of the laboratory. The first time the sample is assayed, the result is 600 mg/dL. To verify this result (following this hospital's policy), the tech makes 2 mL of a 1:2 dilution of the original sample. If only 1 mL of this sample is analyzed, what would the result be? Assume that the original 600 mg/dL value was accurate and that the instrument did not automatically perform a dilution calculation.
300 mg/dL
Probe
A fragment of nucleic acid that is complementary to another nucleic acid sequence; it is labeled and used to identify the complementary sequence.
Oligonucleotide
A short synthetic strand of nucleic acid
Target
A specific region of DNA or RNA unique to the organism, mutation, or disease that is detected by the molecular testing method
The accuracy of an immunoassay is its ability to discriminate between results that are true positives and results that are true negatives. Two parameters of test accuracy are specificity and sensitivity. Which of these statements apply to an immunoassay with high specificity, but low sensitivity?
Accurately identifies the absence of disease Has few false-positives
Compliance standards, policies and procedures apply to:
All employees in the company regardless of their position, job description or title
The laboratory test used to determine the presence of neural tube defects is:
Alpha-fetoprotein
A febrile nonhemolytic transfusion reaction is characterized by which of the following?
An increase in temperature of >1 degree C above 37 degrees during transfusion
Which of the following antibodies will most likely not be detected on immediate spin?
Anti-Jka
CREST syndrome
Anticentromere antibodies
Primary biliary cirrhosis-
Antimitochondrial antibodies
The presence of hyaline, septate hyphae, and a young conidiophore with a foot cell and a swollen vesicle in a fungus culture are excellent clues indicative of:
Aspergillus
All of the following are sources of serum alkaline phosphatase except:
Brain
Which ethnic group has the highest incidence of hereditary hemochromatosis in the United States?
Caucasians of Celtic descent
Which of the following actions would be incorrect when determining quality control (QC) limits for a new lot of control that is being tested in parallel with the old lot of control? Deleting QC results greater than +/- 2 standard deviations Using QC data from the previous month Using target values suggested by the manufacturer as a starting point for establishing QC ranges Including QC data from afternoon and night shifts
Deleting QC results greater than +/- 2 standard deviations
Hemoglobinopathies can be caused by all of the following structural defects EXCEPT:
Deletion of a globin chain. DO: Substitution of amino acids in a globin chain. Deletion of an amino acid in a globin chain. Addition of an amino acid in a globin chain. Fusion of globin chains.
A two-year old male patient has the following hemogram results: Hgb = 6.7gms/dl Hct = 20% Platelets = 355,000/ mm3 RBC = 3.0mil/cmm WBC = 8750/cmm Differential = 6 eos 20 segs 68 lymphs 6 monos
Dietary iron deficiency
When AHG or Coombs serum is used to demonstrate that red cells are antibody coated in vivo, the procedure is termed:
Direct technique
Which test is performed to assess the average plasma glucose level that an individual maintained during the previous 10 week to 12 week period?
Glycated hemoglobin
Which of the following parts of the body synthesizes and secretes BNP?
Heart
Postsplenectomy syndrome
Howell-Jolly bodies remaining in the circulation after splenectomy.
All of the species listed below produce microconidia that aggregate in clusters: •Trichoderma species •Acremonium species •Fusarium species •Gliocladium species
True
The rheumatoid factor in rheumatoid arthritis is PRIMARILY which type of immunoglobulin?
IgM
In hemolytic disease, the urine bilirubin test result is negative and the urine urobilinogen test result is:
Increased
The results which would be MOST consistent with macro-amylasemia are?
Increased serum amylase and normal to low urine amylase values
What is the most significant cause of decreased haptoglobin levels?
Intravascular hemolysis
Which of the following is necessary for the absorption of Vitamin B12:
Intrinsic factor
Which substance acts as a mordant in the Gram Stain process?
Iodine
The migration rate of proteins on cellulose acetate is primarily the result of:
Ionic charge on the proteins
Substances found in urinary sediment that are more easily distinguished by use of polarized microscope are:
Lipids Lipids tend to form a "maltese cross" pattern when viewed in polarized light, which helps to differentiate them from other urine microscopic components.
Multiple flagella at one end
Lophotrichous
Hereditary sideroblastic anemia
Pappenheimer bodies, appearing as tiny blue-staining bodies in Wright-stained smears (confirmed with an iron stain), often in pairs and more commonly at the periphery of the cell characteristically found in sideroblastic anemia
Hematocrit is:
Percentage of blood made up of red cells
Which one of the following statements about iron deficiency anemia is false:
Platelet count in iron deficiency is usually decreased *The platelet count in iron deficiency is often increased.
A nitrate test is performed on a glucose nonfermenter. When the nitrate reagents were added, no color change occurred. When zinc dust was added, no color developed. This test should be reported as:
Positive for nitrogen gas and negative for nitrite production
scattered acanthocytes, echinocytes, target cells, spherocytes, and schistocytes. The condition in which each of these atypical RBC's may be found in varying numbers in the same peripheral blood smear is most likely:
Postsplenectomy syndrome
Treatment of sequestration crisis may include chronic transfusion, exchange transfusion, and/or splenectomy.
TRUE
Which potent inhibitor of platelet aggregation is released by endothelial cells?
Prostacyclin
The following BEST describes serum hCG levels during pregnancy:
Rapid rise in levels during first trimester; slow decline and possible level-off throughout remainder of pregnancy
This Gram-positive coccus is catalase positive. The tests below are a tube coagulase test where rabbit plasma is inoculated with the isolate and a plate containing 4% NaCl and 6µg/mL of oxacillin. A 0.5 McFarland standardized inoculums of the isolate is inoculated to the plate. What step should you take next?
Report the isolate as methicillin resistant Staphylococcus aureus.
Which of the following test(s) that are the most useful in separating Listeria monocytogenes from Erysipelothrix rhusiopathiae?
Room temperature motility Catalase Esculin hydrolysis
Which of the following mechanisms involve a series of interrelated chemical processes that lead to the formation of durable fibrin strands?
Secondary hemostasis
a TSI agar slant shows a neutral or slightly alkaline slant, acid butt, no/gas production, and no H2S production, the organism might be:
Shigella dysenteriae
Which of the following is most likely to interact with arterial walls, leading to deposition of cholesterol, and initiating or worsening atherosclerosis?
Small dense LDL associated with more than a three-fold increase in the risk of coronary heart disease.
Why are small dense LDL molecules more atherogenic
Small dense LDL molecules have greater mobility in the endothelium and arterial wall
Not wiping away the first drop of blood prior to specimen collection
Specimen contaminated or diluted with tissue fluid
The McFarland Comparison Card
Standardize concentrations of organisms
In real-time PCR procedures, fluorescence resonance energy transfer (FRET) is the process that allows for probes to emit fluorescence only after hybridization
TRUE
Tiny volumes of D+ red cells (e.g., as little as 0.1 mL) can stimulate production of anti-D in some individuals.
TRUE
Which of the following statements about Rickettsia is false
They are cultured in many hospital laboratories
Which of the following factors would not affect an orally-administered drug's absorption and/or distribution in the body?
The position of the patient when the drug is taken (sitting vs. standing)
DNA or RNA Togavirus: Coronavirus: Herpesvirus: Adenovirus:
Togavirus: RNA Coronavirus: RNA Herpesvirus: DNA Adenovirus: DNA
The hepatitis B virus vaccine was administered to MLS students during Orientation.Which type of immunity is expected to develop and provide long-term protection?
active
Given the following results, what is the immune status of the patient? HbsAg: positive HbeAg: positive Anti-HBc IgM: positive Anti-HBs: negative
acute infection Anti-Hbc IgM is present due to the immune response to the presence of the hepatitis core antigen and indicates an acute infection
8-Hydroxyquinoline and 0-Cresolphthalein complexone reagent is commonly used in the determination of:
calcium
The purpose of C3a, C4a, C5a, the split-products of the complement cascade, is to:
cause increased vascular permeability, contraction of smooth muscle, and release of histamine from basophils.
Failure to mix a specimen containing an anticoagulant by inverting the sealed specimen container several times after collection of the specimen
clots in specimen
Iontophoresis is a technique used in the diagnosis of:
cystic fibrosis
Holding the hand from which blood is being collected in an upward position during collection of the specimen.
decreased blood flow
Autoimmune hemolytic anemia
displays very finely granular basophilic stippling
Puncture of the cleansed site before alcohol is completely dry
hemolysis
Testing for dsDNA antibodies is usually done on
homogeneous ANA patterns. However, some labs will suggest both dsDNA and ENA testing if the speckled pattern is greater than 1:160.
The expected glucose value of an ABNORMAL 2-hour post-glucose tolerance test is:
markedly elevated glucose levels; above fasting levels
Recurrent fever
plasmodium ring form of Falciparium malaria
Primary hemostasitic processes resulting from vascular damage include all of the following EXCEPT:
rapid vascular dilation occurs
Given the following results, what is the immune status of the patient? HBsAg: negative HBeAg: negative Anti-HBc: positive Anti-HBs: positive
recovery
