7.4 Amniotic, Gastrointestinal, and Seminal Fluids

Question 1

Which of the following statements about amniotic fluid bilirubin measured by scanning spectrophotometry is true?

Answer 1

The 410-nm peak is caused by hemoglobin and the 450-nm peak is caused by bilirubin

Question 2

Which test best correlates with the severity of hemolytic disease of the fetus and newborn (HDFN)?

Answer 2

Amniotic fluid bilirubin

Question 3

Which is the reference method for determining fetal lung maturity (FLM)?

Answer 3

L/S ratio

Question 4

Which of the following statements regarding the L/S ratio is true?

Answer 4

A ratio of 2:1 or greater usually indicates adequate pulmonary surfactant to prevent RDS

Question 5

Which of the following conditions is most likely to cause a falsely low L/S ratio?

Answer 5

Centrifugation at 1,000 × g for 10 minutes

Question 6

Which of the following statements accurately describes human chorionic gonadotropin (hCG) levels in pregnancy?

Answer 6

In ectopic pregnancy, serum hCG doubling time is below expected levels

Question 7

Which of the following statements regarding pregnancy testing is true?

Answer 7

A false-positive result may occur in patients with heterophile antibodies

Question 8

SITUATION: A pregnant woman was seen by her physician, who suspected a molar pregnancy. An hCG test was ordered, and hCG levels were found to be low. The sample was diluted 10-fold and the assay was repeated. The level was found to be grossly elevated. What best explains this situation?

Answer 8

Antigen excess caused a falsely low result in the undiluted sample

Question 9

Which assay result is often approximately 25% below the expected level in pregnancies associated with Down syndrome?

Answer 9

Serum unconjugated estriol

Question 10

Which of the following statements about alpha fetoprotein (AFP) is correct?

Answer 10

Maternal serum may be used to screen for open neural tube defects

Question 11

First-trimester screening for Down syndrome can be performed using which markers?

Answer 11

Free β hCG and pregnancy-associated plasma protein A

Question 12

When performing marker screening tests for Down syndrome, why are results
expressed in multiples of the median (MoM), rather than in concentration?

Answer 12

MoM normalizes for gestational age

Question 13

Which test for 21 trisomy is not recommended for women who are carrying twins?

Answer 13

Maternal plasma cell free fetal DNA

Question 14

Which statement regarding the fetal fibronectin test is true?

Answer 14

The test should not be performed before week 24 or after the end of week 34

Question 15

What is the term for spermatozoa in which the anterior portion of the headpiece is smaller than normal?

Answer 15

Acrosomal deficiency

Question 16

What is the most common cause of male infertility?

Answer 16

Varicocele

Question 17

Which of the following values is the lower limit of normal for sperm concentration?

Answer 17

15 million per milliliter

Question 18

Which morphological abnormality of sperm is most often associated with varicocele?

Answer 18

Tapering of the head

Question 19

Which of the following stains is used to determine sperm viability?

Answer 19

Eosin Y

Question 20

Which of the following semen analysis results is abnormal?

Answer 20

Volume 1.0 mL

Question 21

Which of the following sample collection and processing conditions will lead to inaccurate seminal fluid analysis results?

Answer 21

Sample collected following coitus

Question 22

When performing a seminal fluid analysis, what is the upper limit of normal for WBCs?

Answer 22

1 × 10^6/mL

Question 23

Which carbohydrate measurement is clinically useful when performing a seminal fluid analysis?

Answer 23

Fructose

Question 24

Which condition is most often associated with gastric ulcers?

Answer 24

Helicobacter pylori infection

Question 25

In which condition is the highest level of serum gastrin usually seen?

Answer 25

Z-E syndrome

Question 26

In determining free HCl, the gastric fluid is titrated to pH ______.

Answer 26

3.5

Question 27

Which test can identify persons with gastrin-secreting tumors that do not demonstrate a definitively increased plasma gastrin concentration?

Answer 27

Secretin stimulation

Question 28

Which of the following tests would be normal in pancreatic insufficiency?

Answer 28

D-Xylose absorption

Question 29

Which of the following is commonly associated with occult blood?

Answer 29

Colon cancer

Question 30

Which test is most sensitive in detecting persons with chronic pancreatitis?

Answer 30

Fecal elastin-1