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A 1-week-old newborn has had poor feeding,
vomiting, and
progressive lethargy over the past 4 days. She was
born at term; pregnancy,
labor, and delivery were uncomplicated, and she had no
congenital
anomalies. She is being breast-fed. She has a
healthy 2-year-old brother; a
sister died at 10 days of age after a full-term birth.
Examination
shows decreased muscle tone and poor responsiveness;
reflexes are normal.
Serum bicarbonate level is 8 mEq/L, pH is 7.15, and
plasma ammonia
level is 10 times the upper limit of normal. Which of
the following is the
most likely cause?

A
) Mitochondrial disorder

B
) Mucopolysaccharidoses disorder

C
) Organic acid metabolism disorder

D
) Renal tubular acidosis

E
) X-linked leukodystrophy
Organic acid metabolism disorder....by exclusion...i guess
yeah right, thts wht i thot too. i am trying to figure out wht exactly this is, there is so much to cover from step1!
any other inputs please?
C) Organic acid metabolism disorder
i think this may be OTC deficiency
ok thanks a lot and good luck.