Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (672 page)

   Limitations

   Immunoassay testing for ethanol may have cross-reactivity <1% with isopropanol alcohol, methanol, ethylene glycol, and acetaldehyde; <15% with
n
-propanol.

   Elevated concentrations of acetone are detected in specimens during diabetic ketoacidosis and fasting ketoacidosis and may range from 10 to 70 mg/dL.

   In many headspace gas chromatographic methods, acetonitrile coelutes with acetone, leading to a false-positive result. Acetonitrile may be a component in cosmetic nail remover.

   A positive urine ethanol due to the presence of yeast in the patient’s urine has been described. In these cases, glucose was also present in the urine.

ALDOSTERONE

   Definition

   Primary mineralocorticoid secreted by the adrenal zona glomerulosa. The role of aldosterone in metabolism is the control of sodium and potassium. Regulating sodium ion concentration, in turn, regulates fluid volume. Aldosterone acts to decrease excretion of sodium and increase the excretion of potassium at the kidney, sweat glands, and salivary glands.

   
Normal range:

   8:00–10:00
AM
(sitting): 3–34 ng/dL

   8:00–10:00
AM
(supine): 2–19 ng/dL

   4:00–6:00
PM
(sitting): 2–23 ng/dL

   Use

   Diagnosis of primary hyperaldosteronism