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+--- Thread: d4 - sami2004 (/showthread.php?tid=603843)
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d4 - sami2004 - ArchivalUser - 08-04-2011
A man is brought to the hospital with a depressed level of consciousness.
He was found by the police beside a dumpster behind
an automotive shop. He has no identification. On examination,
his supine pulse rate is 108 beats per minute and supine blood
pressure is 98/64 mm Hg; orthostatic changes cannot be determined
because the patient cannot sit upright. His breath has a
sweet, fruity odor. The optic fundi appear normal, and both
pupils react briskly to light. Cardiovascular examination is unremarkable
except for regular tachycardia. The abdomen is not
tender. No peripheral edema is present. There are no suspicious
skin lesions. Laboratory evaluation showed the following:
Plasma glucose, mg/dL 100
Blood urea nitrogen, mg/dL 16
Serum creatinine, mg/dL 1.0
Serum electrolytes
Sodium, mEq/L 138
Potassium, mEq/L 3.9
Chloride, mEq/L 101
Bicarbonate, mEq/L 10
Arterial blood studies
PO2, mm Hg 134
PCO2, mm Hg 28
pH 7.28
Urinalysis showed sheets of needle-shaped, monohydrate calcium
oxalate crystals.
Which of the following is the most likely diagnosis?
a. Methanol intoxication
b. Crystal methamphetamine overdosage
c. Ethylene glycol intoxication
d. Alcoholic ketoacidosis
e. Salicylate overdosage
0 - ArchivalUser - 08-04-2011
c. Ethylene glycol intoxication
0 - ArchivalUser - 08-04-2011
c.
0 - ArchivalUser - 08-04-2011
c,,,,,,,
0 - ArchivalUser - 08-04-2011
c is the answer
0 - ArchivalUser - 08-04-2011
i thought ethanol toxicity oxalic crystals were envelope shaped..
0 - ArchivalUser - 08-04-2011
and fruity odor hmm i want to say alcoholic ketoacidosis
0 - ArchivalUser - 08-04-2011
C........
0 - ArchivalUser - 08-04-2011
C.......raised anion gap and oxalate crystals ethylene glycol
0 - ArchivalUser - 08-04-2011
Answer c.
This patient presents with altered mental status, mild tachycardia,
and hypotension. A fruity odor is noted on his breath. His laboratory
results are consistent with a high anion gap metabolic acidosis.
Another clue is the presence of oxalate crystals in the urine. The differential
diagnosis of this form of metabolic acidosis is the fodder for
many mnemonics, such as SLUMPED (salicylates, lactic acidosis,
uremia, methanol/ethylene glycol, paraldehyde, ethanol, and diabetic
ketoacidosis). The fruity smell suggests ketosis. Oxalate crystals are
a specific sign of ethylene glycol toxicity. Both methanol and ethylene
glycol require the enzyme alcohol dehydrogenase for metabolism.
Patients intoxicated with methanol or ethylene glycol can present
with metabolic acidosis, hyperpnea and tachypnea, coma, seizures,
and hypotension. Methanol leads to the formation of formate, which
causes retinal damage with optic disc hypemia and edema, blindness,
and basal ganglia infarcts. Ethylene glycol causes the formation of
calcium oxalate crystals, leading to renal failure and hypocalcemia.
Methanol and ethylene glycol intoxication are treated with fomepizole
or ethanol, which inhibit alcohol dehydrogenase