Your recent article on Insulin Resistance in the Winter 2006 edition was an excellent review of many issues confronting the clinician in diagnosing and treating Metabolic Syndrome. Several issues, however, require further clarification.
Dr. Mark Houston cites the use of SpectraCell Laboratories for testing deficiencies of various vitamin, minerals and antioxidants. The article describes the Functional Intracellular Analysis™ (FIA™) as measuring micronutrient content within the lymphocytes. Actually, the testing measures the function of the various nutrients within a patient's living lymphocytes grown in tissue culture. Normal serum measurements often mask functional deficiencies.
Also, Dr. Jan Troup, Director of Lipid Sciences at SpectraCell, is quoted in the story as indicating that the Metabolic Syndrome can be diagnosed solely on lipid measurements. Clearly the inclusion of fasting insulin and glucose levels, hypertension, obesity, and clinical history are also important. SpectraCell's Lipoprotein Particle Profile™ (LPP™) can identify additional risk factors including dense HDL and LDL subfractions, remnant lipoprotein and a shift toward high triglyceride-rich VLDL levels.
The good news: both testing services—the FIA and the LPP—are reimbursable under Medicare and many insurance plans for a wide range of ICDM codes.
J. Fred Crawford, PhD
Vice President & Laboratory Director
Houston, TX 77072