boc ascp Flashcards
when using an automated cell counter, what occurs in the case of a cold agglutination?
increased MCV (and MCHC) and rbc
CSF specimen for glucose assay should be
analyzed immediately
a major crossmatch will detect
recipients antibodies directly against donors red cells
The anion gap is useful for quality control of laboratory results for
sodium, potassium, chloride and total C02
common cause of respiratory alkalosis is
hyperventilation
When staining acid-fast bacilli with Truant auramine-rhodamine stain, potassium permanganate is used as a
quenching agent
A first morning sputum is received for culture of acid-fast bacilli. It is digested and concentrated by the
N-acetyl-L-cysteine alkali method. Two Sabouraud dextrose slants are incubated in the dark at 35ºC with
5%-10% CO2. The smear reveal acid-fast bacilli, but the slants show no growth after 8 weeks. The
explanation is:
incorrect media was used
maconkey media screening for suspected cases of E.coli 0517:H7 must contain
sorbitol
A patient with a B-cell deficiency will most likely exhibit
bacterial infections
IgM antibodies are frequently hemolytic because of
their 5 antigen-binding sites
A community hospital microbiology laboratory is processing significant numbers of stool cultures
because of an outbreak of diarrhea following heavy rains and flooding in the county. A media that
should be incorporated in the plating protocol is:
thisulfate citrate bile salts sucrose for Vibrio species
An electrode has a silver/silver chloride anode and a platinum wire cathode. It is suspended in KCl
solution and separated fro the blood to be analyzed by a selectively permeable membrane. Such an
electrode is used to measure which of the following?
pco2
The organism most commonly associated with neonatal purulent meningitis is
group b strep
The volume of urine excreted in a 24-hour period by an adult patient was 300mL. This condition would
be termed
oliguria
Amniotic fluid is tested for the concentration of lamellar bodies. This test determines
fetal lung maturity
the purpose of testing with Anti-A-B is
to detect subgroups of A
The most important buffer pair in plasma is the
bicarbonate/carbonic acid pair
Evidence of active red cell regeneration may be indicated on a blood smear by
basophilic stippling, nucleated rbcs, and polychromasia
Which of the following is most closely associated with chronic myelogenous leukemia
Philideplphia chromosome
All stages of neutrophils can be seen in the peripheral blood smear of a patient with
chronic granulocytic leukemia (CML)
to be analyzed by gas liquid chromatography a compound must
volatile or must be made volatile
Rheumatoid factors are immunoglobulins with specificity for allotypic determinants located on the
Fc fragment of IgG
Substances that are ANTIGENIC ONLY when coupled to a protein carrier
haptens
Which of the following immunoglobulins is the most efficient at agglutination
IgM
Use of “standard” (universal) precautions minimizes exposure to
blood-borne pathogens
Which of the following is true about direct ion selective electrodes for electrolytes
whole blood specimens are acceptable
Leukocyte reduced red blood cells are ordered for a newly diagnosed bone marrow candidate . Which
way is the best way to prepare this product
Transfuse through a log3 leukocyte removing filter
the steam autoclave method of sterilization
15 lb of pressure for 15 min
Factors that contribute to a PCO2 electrode requiring 60-120 seconds to reach equilibrium include the
diffusion characteristics of the membrane
Of the following, the disease most closely associated with pale blue inclusions in granulocytes and giant
platelets is
May-Hegglin
Which of the follwing factors would make an organism appear to be more resistant on a disk diffusion sustibility test?
too many organisms on the disc
In spectrophotometry, the device that allows for a narrow band of wavelengths is the
monochromator
Leukocyte-poor red blood cells would most likely be indicated for patients with a history of
febrile transfusion reactions
In synovial fluid, the most characteristic microscopic finding in pseudogout is
calcium pyrophosphate dihydrate crystals
an index of precision is statistically known as
coefficient of variation
AHG coombs control cells are coated with
IgG antibody
Which laboratory technique is most frequently used to diagnose and follow the course of therapy of a
patient with secondary syphilis?
flocculation
The disease most often associated with elevations of lactate dehydrogenase isoenzymes 4 and 5 on
electrophoresis is
liver disease
The most appropriate screening test for hemoglobin F is:
Kleihauer-Betke
An enzyme deficiency associated with a moderate to severe hemolytic anemia after the patient is
exposed to certain drugs and that is characterized by red cell inclusions formed by denatured
hemoglobin is
G6PD-defieciency
which one of the following gram-negative bacilli ferments glucose
Y. enterocolitica
Tumor markers are useful in tracking
the efficiency of treatment
Which of the following is the most reliable test to differentiate Neisseria lactamica from Neisseria
meningitis?
lactose degradation
Which of the following may be used a a positive quality control organism for the bile esculin test
enterococcus faecalis
The major features by which molds are routinely identified are
Macroscopic characteristics and
microscopic morphology
hemorrhage in polycythemia vera is a result of
abnormal platelet function
Vibrio parahemolyticus can be isolated best from feces on
TCBS agar
Antibodies composed of IgG immunoglobulin
are able to cross the placenta
Antibody idiotype is dictated by the
regions of light and heavy chains
lithium therapy is widely used to treat
bipolar disorder
After receiving appropriate training, the first step in using a fire extinguisher is to
pull the pin
Tumor markers found in the circulation are most frequently measured by
immunoassays
Which of the following antigens is most likely to be involved in hemolytic disease of the newborn?
Kell
A Patient with a coagulopathy was transfused with FP24 (plasma frozen within 24 hours of collection)
After infusion of 15mL, the patient experienced hypotension, shock, chest pain and difficulty in
breathing. The most likely cause of the reaction is
Anti-IgA
False-positive results can occur for fecal occult blood due to the ingestion of
horse-radish
A consistently and repeatedly negative IFA-ANA is
strong evidence against untreated SLE
What kind of antigen-antibody reaction would be expected if soluble antigen is added to homologous
antibody?
precipitation
the Philadelphia chromosome is formed by a translocation between the
long arm of chromosome 22 and long arm of chromosome 9
Ten units of group A platelets were transfused to a group AB patient. The pretransfusion platelet count
was 12x10^3/uL and the posttransfusion count was 18x10^3/uL. From this information, the technologist
would most likely conclude that the patient
has developed antibodies against the transfused platelets
A solution contains 20 g of solute dissolved in 0.5 L of water. What is the percentage of this solution?
4%
A technician is asked to clean out the chemical reagent storeroom and discard any reagents not used in
the past 5 years. How should the technician proceed?
follow MSDS protocal
in a the clauss fibrinogen method, the time to clot formation in plasma is measured after the addition
of
thrombin
a centrifuge head has a diameter of 60 cm and spins at 3,000 RPM. What is the maximum achievable G
force?
2,700 G
A technologist spilled 10 gallons of formaldehyde on the floor. After determining the chemical poses a
significant health hazard, the first action step would be to
evacuate the area
A first morning sputum is received for culture of mycobacteria. It is digested and concentrated by the Nacetyl-L-cysteine alkali method. Two Lowenstein-Jensen slants are incubated in the dark at 35C with 5-
10% CO2. The smears revealed acid-fast bacilli, and after 7 days no growth appears on the slants. The
best explanation is
not enough time for growth (mycobacterium can take up to 12 weeks to grow)
In the assay of lactate dehydrogenase, which of the following products is actually measured?
NADH
A sputum specimen from a patient with a known Klebsiella pneumonia infection is received in the lab for fungus culture. The proper procedure for handling this specimen is to
include media that have cycloheximide and chloramphenicol to inhibit bacteria and saprophytic fungi
Humoral antibodies are produced by
B lymphs
What battery of tests is most useful in evaluating an anion gap of 22 mEq/L (22 mmol/L)?
BUN,creatinine, salicylate and methanol
Which of the following factors is used only in the extrinsic coagulation pathway?
VII
In flow cytometric analysis, low angle or forward scatter of a laser light beam provides information that pertain to a cell’s
volume
For safe operation of a centrifuge
ensure proper balance is maintained
Which of the following activities is associated with C3b?
opsonization
Which of the following specimen requests is acceptable
urine for acid-fast bacilli culture
In polycythemia vera, the platelet count is
increased/elevated
A mass spectrometer detects which property of ionized molecules
mass to charge ration
Severe intravascular hemolysis is most likely caused by antibodies of which blood group system?
ABO
urine specific gravity is an index of the ability of the kidney to
concentrate the urine
When using the turbidity (solubility) method for detecting the presence of hemoglobin S, an incorrect
interpretation may be made when there is a(n)
increase in total serum protein
When cleaning up a small (5 mL) blood spill on the counter-top, the first step after donning appropriate
personal protective equipment is to:
absorb the spill with disposable absorbent material
A serum sample was assayed for bilirubin at 10 AM, and the result was 12 mg/dL (205.6 µmol/L). The
same sample was retested at 3 PM. The result now is 8 mg/dL (136.0 µmol/L). The most likely
explanation for this discrepancy is
the sample was exposed to light
After receiving a 24-hour urine for quantitative total protein analysis, the technician must first
measure the total volume
which of the following is a characteristic of polyagglutinable red cells
are agglutinated by most anti-sera
The purpose of a low-dose irradiation of blood components is to
prevent GVHD
the genus of virus associated with anogenital wart, cervical dysplasia and neoplasia is
papillomavirus
An emphysema patient suffering from fluid accumulation in the alveolar spaces is likely to be in what metabolic state?
respiratory acidosis
An automated CK assay gives a reading that is above the limits of linearity. A dilution of the serum
sample is made by adding 1 mL of serum to 9 mL of water. The instrument now reads 350 U/L. the
correct report on the undiluted serum should be
3500 u/L
Precautions for health care workers dealing with patients or patient specimens include
prompt cleaning of blood spills with a disinfectant solution such as sodium hypochlorite
Which of the following is most likely to be ordered in addition to serum calcium to determine the cause
of tetany?
magnesium
Aspartate amino transferase (AST) is characteristically elevated in diseases of the
AST
The appearance of normal CSF is
clear and colorless
A blood gas sample was sent to the lab on ice, and a bubble was present in the syringe. The blood has
been exposed to room air for at least 30 minutes. The following change in blood gases will occur
PO2 increased/HCO3 decreased
A technologist spilled concentrated hydrochloric acid on his/her clothing and skin, affecting a large
portion of the body. After removing involved clothing, the next first aid treatment step would be to
use emergency body shower and flush with water
If present, a characteristic that is helpful in separating Pseudomonas aeruginosa from other members of
Pseudomonas family is
growth at 42 degrees
A patient with uncontrolled diabetes mellitus will most likely have
high SG with pale colored urine
a blood donor has the genotype: hh, AB. What is his red blood cell phenotype?
O
Darkfield microscopy is can be used to visualize?
T. pallidum
an organism from a peritoneal abscess is isolated on kanamycin-vancomycin laked blood agar and grows
black colonies on BBE agar. It is nonpigmented, catalase positive and indole negative. The genus of this organism is
Bacteroides
A 25 year old woman is seen by a physician because of Raynaud’s phenomenon, myalgias, arthralgias,
and difficulty in swallowing. There is no evidence of renal disease. An ANA titer is 1:5120 with a speckled
pattern with mitotic. Which of the following is also likely to be found in this patient?
high level RNP (ribonucleoprotein) antibody
The direction in which albumin migrates (ie. toward anode or cathode) during electrophoretic
separation os serum proteins, at pH 8.6, is determined by
the ionization of the acrboxyl groups, yielding a net negative charge
A urine culture had the following culture results:
-sheep blood: swarming
-CNA: no growth
-Mac: 1. >100,000 CFU/mL NLF
2. >100,000 CFU/mL NLF with red pigment
The isolates from Mac had the following biochemical reactions:
TEST ISO 1 ISO2
TSI alk/acid alk/acid
urea pos neg
TDA pos neg
H2S pos neg
P. mirabilis and S. marcescens
The tau isoform of transferrin is a carbohydrate deficient protein found only in
CSF
Flocculation tests for syphilis use antigen composed of
cardiolipin and lecithin
The Liley method of predicting the severity of hemolytic disease of the newborn is based on the
amniotic fluid
change in optical density measured at 450 nm
A low concentration of serum phosphorus is commonly found in
patients who are receiving carbohydrate hyperalimentation
In a relationship testing case, the child has a genetic marker that is absent in the mother and cannot be
demonstrated in the alleged father. What type of paternity exclusion is this known as?
direct
Routine screening of urine samples for glycosuria is performed primarily to detect
glucose
DNA-based testing for the presence of MRSA uses PCR with primers specific for which gene?
mec-A
The following data were calculated on a series of 30 determinations of serum uric acid control:
mean=5.8 mg/dL, 1 standard deviation=0.15 mg/dL. If the confidence limits are set at +or-2 SD, which of
the following represents the allowable limits for the control?
5.50-6.10 mg/dL
A fluid sample waas collected by throcentesis. A serum sample was collected immediately afterward.
The LD fluid to serum ratio was 0.9. there were 5,000 WBC/uL, with 75% PMNs Which of the following
describes this fluid.
Plural effusion exudate
What is the MCV if the hematocrit is 20%, the RBC is 2.4 x 10^6/uL and the hemoglobin is 5 g/dL?
83
which of the following mediators are released during t-cell activation
cytokines
CSF for glucose assay should be analyzed
analyzed
The automated platelet count on an EDTA specimen is 58 x 103/pL. The platelet estimate on the blood
smear appears normal, but it was noted that the platelets were surrounding the neutrophils. The next
step should be to
recollect specimen using different anticoagulant
The biuret reaction for the analysis of serum protein depends on the number of
peptide bonds
which of the following genera include anaerobic gram-negative non-sporulating bacilli?
Bacteroides
An antibiotic used to suppress or kill contaminating fungi in media is:
cycloheximide
Higher levels of employees motivation occur when the supervisor
collaborates to set goals to be accomplished
Which stain is used to used to measure sperm viability?
eosin nigrosin
The most important use of a nontreponemal antibody (NTA) test alone is in
evaluation of the success of therapy
A nonchromogen that grows best at 42 degree C and is highly resistant to antibiotics is
Mycobacterium xenopi
Microscope analysis of a urine specimen yields a moderate amount of red blood cells in spite of a
negative result for occult blood using a reagent strip. The technologist should determine if this patient
has taken
vitamin c
Nephelometers measure light
at a scattered right angle to the light path
A first morning sputum is received for acid-fast culture. The specimen is centrifuged and the sediment is inoculated on Two Lowenstein-Jensen slants, which are incubated at 35C with 5-10% CO2. After 1 week, the slants show abundant growth over the entire surface. Strains reveal gram-negative bacilli. To avoid this problem..
decontaminate the specimen with sodium hydroxide
Polarized light can often be used to differentiate between
fibers and mucous clumps
Which of the following clinical disorders is associated with the greatest elevation of lactate
dehydrogenase isoenzyme 1?
pernicious anemia
