A nurse is assessing a child who has rhabdomyosarcoma of the nasopharynx. What is an expected finding for this malignancy?

Choice A reason: This test will confirm if your child had a recent streptococcal infection, as it measures the level of antibodies that the body produces against the streptolysin O enzyme, which is produced by some strains of streptococcal bacteria. A high ASO titer indicates a recent or current streptococcal infection, which can trigger rheumatic fever in some children.

Choice B reason: This test will not indicate if your child has rheumatic fever, as it does not measure the inflammation or damage to the heart, joints, or other organs that rheumatic fever can cause. Rheumatic fever is diagnosed based on the presence of two major or one major and two minor criteria, as well as evidence of a preceding streptococcal infection.

Choice C reason: This test will not indicate if your child has a therapeutic blood level of an aminoglycoside, as it does not measure the concentration of this type of antibiotic in the blood. Aminoglycosides are used to treat serious infections caused by gram-negative bacteria, and their blood levels need to be monitored to prevent toxicity and ensure efficacy.

Choice D reason: This test will not confirm if your child has immunity to streptococcal bacteria, as it does not measure the level of protective antibodies that can prevent future infections. ASO antibodies are not protective, but rather indicate a past or present exposure to streptococcal bacteria.

Choice A reason: 60 beats per minute is too low for an infant's apical heart rate. The normal range for a 6-month-old infant is 100 to 160 beats per minute. A low heart rate can indicate digoxin toxicity, which can cause serious complications such as bradycardia, arrhythmias, and cardiac arrest.

Choice B reason: 80 beats per minute is also too low for an infant's apical heart rate. The normal range for a 6-month-old infant is 100 to 160 beats per minute. A low heart rate can indicate digoxin toxicity, which can cause serious complications such as bradycardia, arrhythmias, and cardiac arrest.

Choice C reason: 100 beats per minute is the lower limit of the normal range for a 6-month-old infant's apical heart rate. The nurse should withhold the dose of digoxin if the infant's apical heart rate is less than 100 beats per minute, as this can indicate digoxin toxicity, which can cause serious complications such as bradycardia, arrhythmias, and cardiac arrest.

Choice D reason: 120 beats per minute is within the normal range for a 6-month-old infant's apical heart rate. The nurse does not need to withhold the dose of digoxin if the infant's apical heart rate is 120 beats per minute, as this does not indicate digoxin toxicity. However, the nurse should still monitor the infant's heart rate, blood pressure, and digoxin level closely, as digoxin has a narrow therapeutic window and can cause adverse effects even at therapeutic doses.