​Calcium is found in three major forms in circulation: protein-bound, anion-bound, and ionized or free.  To begin on a side note, the term “ionized” calcium is somewhat misleading, as even calcium bound to protein or anions is in fact ionized; from here on I’ll refer to unbound calcium as free.  Se...(Read More)

​Surrogate can be a verb (to appoint a representative), an adjective (providing or receiving nurture or parental care though not related by blood or legal ties), or a noun (a stand-in or substitute). Several laboratory tests function as surrogates for analytes that are difficult or impractical to m...(Read More)

​For decades, many laboratories have performed chemistry testing on non-standard body fluids (NSBF).  NSBFs include everything beyond a blood or urine sample, including but not limited to: CSF, pleural, synovial, peritoneal, dialysate, drain, etc (1).  However, the majority of tests that labs offer...(Read More)

​The use of mass spectrometry for clinical diagnostics has grown considerably due in large part to the rapid advancements with liquid chromatography-tandem mass spectrometry (LC-MS/MS). More in-depth discussions of clinical mass spectrometry principles and its uses in the clinical laboratory can be...(Read More)