urinalysis and body fluids- Amniotic, Gastrointestinal, and Seminal Fluids Flashcards
1
Q
- Which of the following statements about
amniotic fluid bilirubin measured by scanning
spectrophotometry is true?
A. The 410-nm peak is due to hemoglobin and the
450-nm peak is due to bilirubin
B. Baseline correction is not required if a scanning
spectrophotometer is used
C. Chloroform extraction is necessary only when
meconium is present
D. In normal amniotic fluid, bilirubin increases
with gestational age
A
A. The 410-nm peak is due to hemoglobin and the
450-nm peak is due to bilirubin
2
Q
- Which test best correlates with the severity
of HDN?
A. Rh antibody titer of the mother
B. Lecithin/sphingomyelin (L/S) ratio
C. Amniotic fluid bilirubin
D. Urinary estradiol
A
C. Amniotic fluid bilirubin
3
Q
- Which is the reference method for determining
fetal lung maturity?
A. Human placental lactogen
B. L/S ratio
C. Amniotic fluid bilirubin
D. Urinary estriol
A
B. L/S ratio
4
Q
- Which of the following statements regarding
the L/S ratio is true?
A. A ratio of 2:1 or greater usually indicates
adequate pulmonary surfactant to prevent
respiratory distress syndrome (RDS)
B. A ratio of 1.5:1 indicates fetal lung maturity in
pregnancies associated with diabetes mellitus
C. Sphingomyelin levels increase during the third
trimester, causing the L/S ratio to fall slightly
during the last 2 weeks of gestation
D. A phosphatidylglycerol (PG) spot indicates the
presence of meconium in the amniotic fluid
A
A. A ratio of 2:1 or greater usually indicates
adequate pulmonary surfactant to prevent
respiratory distress syndrome (RDS)
5
Q
- Which of the following conditions is most likely
to cause a falsely low L/S ratio?
A. The presence of PG in amniotic fluid
B. Freezing the specimen for one month at –20°C
C. Centrifugation at 1,000 × g for 10 minutes
D. Maternal diabetes mellitus
A
C. Centrifugation at 1,000 × g for 10 minutes
6
Q
- Which of the following statements accurately
describes hCG levels in pregnancy?
A. Levels of hCG rise throughout pregnancy
B. In ectopic pregnancy, serum hCG doubling time
is below expected levels
C. Molar pregnancies are associated with lower
levels than expected for the time of gestation
D. hCG returns to nonpregnant levels within
2 days following delivery, stillbirth, or abortion
A
B. In ectopic pregnancy, serum hCG doubling time
is below expected levels
7
Q
- Which of the following statements regarding
pregnancy testing is true?
A. β Subunits of human chorionic gonadotropin
(hCG), thyroid-stimulating hormone (TSH),
and follicle-stimulating hormone (FSH) are
very similar
B. Antibodies against the β subunit of hCG
cross-react with luteinizing hormone (LH)
C. A false-positive result may occur in patients with
heterophile antibodies
D. Serum should not be used for pregnancy tests
because proteins interfere
A
C. A false-positive result may occur in patients with
heterophile antibodies
8
Q
- SITUATION: A pregnant female was seen by her
physician who suspected a molar pregnancy. An
hCG test was ordered and found to be low. The
sample was diluted 10-fold and the assay was
repeated. The result was found to be grossly
elevated. What best explains this situation?
A. The wrong specimen was diluted
B. A pipeting error was made in the first analysis
C. Antigen excess caused a falsely low result in the
undiluted sample
D. An inhibitor of the antigen–antibody reaction
was present in the sample
A
C. Antigen excess caused a falsely low result in the
undiluted sample
9
Q
- Most cases of Down syndrome are the result of:
A. Nondisjunction of an E chromosome (E trisomy)
B. Nondisjunction of chromosome 21 (G trisomy)
C. A 14–21 chromosome translocation
D. Deletion of the long arm of chromosome 21
A
B. Nondisjunction of chromosome 21 (G trisomy)
10
Q
- Which assay result is often approximately 25%
below the expected level in pregnancies associated
with Down syndrome?
A. Serum unconjugated estriol
B. L/S ratio
C. Amniotic fluid bilirubin
D. Urinary chorionic gonadotropin
A
A. Serum unconjugated estriol
11
Q
- Which of the following statements about AFP is
correct?
A. Maternal serum may be used to screen for open
neural tube defects
B. Levels above 4 ng/mL are considered positive
C. Elevated levels in amniotic fluid are specific for
spina bifida
D. AFP levels increase in pregnancies associated
with Down syndrome
A
A. Maternal serum may be used to screen for open
neural tube defects
12
Q
- First-trimester screening for Down syndrome can
be performed using which markers?
A. Alpha fetoprotein and unconjugated estriol
B. Free β hCG and pregnancy-associated plasma
protein A
C. Intact hCG and dimeric inhibin A
D. Dimeric inhibin B and α fetoprotein
A
B. Free β hCG and pregnancy-associated plasma
protein A
13
Q
- When performing marker screening tests for
Down syndrome, why are results expressed in
multiples of the median (MoM) rather than
concentration?
A. Concentration is not normally distributed
B. MoM normalizes for gestational age
C. Some tests cannot be reported in mass units
D. Mean cannot be determined accurately for these
analytes
A
B. MoM normalizes for gestational age
14
Q
- Which statement regarding the fetal fibronectin
test is true?
A. A positive test is correlated with a low probability
of delivery within 14 days
B. The test should not be performed before
week 24 or after the end of week 34
C. The test is performed on amniotic fluid
D. The test is used to identify amniotic fluid after
rupture of the fetal membranes
A
B. The test should not be performed before
week 24 or after the end of week 34
15
Q
- What is the term for sperm when the anterior
portion of the headpiece is smaller than normal?
A. Azoospermia
B. Microcephaly
C. Acrosomal deficiency
D. Necrozoospermia
A
C. Acrosomal deficiency
