11-27-2007, 09:58 PM
15. A 7-week-old boy is brought to the physician
because of fever,
irritability, and lethargy for 3 days. He has had no
vomiting,
diarrhea, or symptoms of an upper respiratory tract
infection. He always seems
hungry to his mother despite being fed 3 ounces of
formula every 3
hours. His mother also notes that he has many wet
diapers throughout the
day and night. He currently appears irritable. His
temperature is 37.8
C (100 F), blood pressure is 80/50 mm Hg, pulse is
150/min, and
respirations are 25/min. Examination shows a sunken
anterior fontanelle.
Mucous membranes are dry. There is tenting of the
skin. Examination
shows no other abnormalities. Urinalysis is negative
for glucose and
protein.
Na+(mEq/L) Cl“(mEq/L) K+(mEq/L) HCO3“(mEq/L)
pH Specific
gravity
A
)
132 89 2.8 39 5.0 1.025
B
)
133 110 3.9 16 6.0 1.015
C
)
163 117 4.3 22 5.5 1.003
D
)
165 115 4.5 19 5.0 1.030