Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (972 page)

   Infancy, pregnancy

   Malnutrition

   Limitations

   Low haptoglobin is normal for the first 3–6 months of life. Haptoglobin is an acute-phase reactant and increases with inflammation or tissue necrosis.

   Three main phenotypes of haptoglobin are known: Hp 1-1, 2-1, and 2-2. Hp 1-1 circulates as a monomer, and Hp 2-1 and 2-2 are polymers.

   Significant interlaboratory variations are observed from the sera of healthy individuals.

HEAVY METALS
*

   Definition

   Elements in the periodic table that form cations due to electron loss when ionized. Metals with a high relative atomic mass and a density >5 g/cm
³
, which include aluminum, arsenic, lead (see p. 1028), mercury, cadmium, copper, selenium, thallium, and zinc

   
Normal range:

   Aluminum: <10 ng/mL (serum)

   Arsenic: <13 ng/mL (blood)

   Cadmium: <5 ng/mL (blood)

   Copper: <10 ng/mL (serum/plasma)