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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

?any body plzzzz

C
She has diabetes insipidus. Na should be high. Specific gravity should be low because she is loosing pure water(ie if urine is concentrated specific gravity would be high)

if this was a renal problem than specific graity will be low b/c kidney unable to concentrate urine so u loose na but u are loosing more water so urine osm will be low and so will specific gravity of urine < 1.025

if this was a prerenal problem than specific gravity will be high b/c kideny is trying to conserve na/cl b/c of dehydration and needs to maintain BP

since ther are no proteins found and UA is normal I am thinking this is a prerenal problem, Pt is dehydrates so serum na/cl levels will be high and so only option u have is CCC

prayforbest, how did u come to the conclusion from the case that this is DI...thx much

anyone else.