About Us. Contact Information. Laboratory Tests for Dietary Professionals: Interpretation and Application

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1 Laboratory Tests for Dietary Professionals: Interpretation and Application Eugenio H. Zabaleta, Ph.D. Clinical Chemist MedCentral Health System About Us Cyndi Guveiyian RD, LD Director of Training and Development Contact Information 171 Green Meadows Drive South Lewis Center, Ohio Phone: Fax:

2 Continuing Education On Demand Webinars Now Available Nutrition Care Process: Practical Application for LTC MDS 3.0, CAA s and Care Planning A TPN Primer: What the RD Needs To Know On Demand Dietary Line Staff Training Standardized Recipes Visit The Learning Center Before We Begin Prior to the webinar, an was sent that provided you with access to: Handouts for the webinar Certificate of Attendance Post Presentation Survey This webinar has been approved for Registered Dietitians and Exempt Practitioners by the American Dietetic Association s (ADA) Commission on Dietetic Registration (CDR) for 1 CEU. The CDR Learning Codes for this webinar are as follows: 3005,3010,5040,5100 Before We Begin A slight delay may occur between slides. There will be an opportunity for questions at the end of this presentation. If you get disconnected, d simply log in again to rejoin the presentation. If you are unable to rejoin the presentation, please contact Kathy at (866) or kathy@dietarysolutions.net 2

3 About Our Speaker Eugenio H. Zabaleta Ph.D. Clinical Chemist MedCentral Health System Dietary Professional Dietary Professional Eat to Heal 3

4 Objectives Recognize nutrition-related laboratory test interferences/limitations. Interpret nutrition-related laboratory values to determine clinical implications. Identify strategies for effective monitoring of nutrition-related laboratory tests. CLIA Clinical Laboratory Improvement Amendments Lab Test Performance Analytical Performance -Accuracy, reproducibility and precision -MLT/MT (Clinical Chemist &/or Pathologist) Clinical Performance -Sensitivity and specificity -Physician (Clinical Chemist &/or Pathologist) 4

5 Case Study (Disagreement between Analytical and Clinical Performance of a lab test) A fifty year-old-male is diagnosed with: Chronic Lymphocytic Leukemia Plasma K + was critical high The nephrologists and Lab decided d to evaluate the patient s K + level with different techniques (communication) Final Diagnosis (related to the K + issue): pseudohyperkalemia with Leukocytosis, due to volume depletion Albumin The most abundant protein in blood Maintain osmotic pressure (prevent edema) Transport hormone, drugs, vitamins, ions It is made in the liver Half life of twenty days (changes slowly) Albumin Decrease in: liver disease, malnutrition, GI tract malabsorption processes (Crohn s disease, Celiac disease), kidney disease, inflammation, shock Increase in: dehydration 5

6 Prealbumin It is a protein produced mainly by the liver Half life of two days (changes rapidly) Gives current nutritional status Prealbumin Decrease in: Malnutrition, Cancer, Hyperthyroidism, chronic illness, liver disease, serious infections Increase in: High-dose corticoids therapy, High-dose nonsteroidal antiinflammatory medications, Hodgkin's disease, Kidney failure (1) What about prealbumin, albumin, and microalbumin tests Albumin & microalbumin tests detect the same molecule (low detection limit in urine measurement issues) Albumin vs. Prealbumin (they are different proteins) Albumin reflects Liver and kidney diseases as well as AA absorption (more widely available test) Prealbumin reflects current nutritional status (short half life) 6

7 (2) Prealbumin/Caveat Low Prealbumin can be seen with inflammation In patients with inflammation and malnutrition the interpretation of Prealbumin result can be more difficult (3) Prealbumin/New Role Prealbumin test can predict poor outcomes for patients on hemodialysis Complications: low (base line ) Mortality: decreasing (trend) Chertow G, Goldstein-Fuchs, Lazarus J, et al. Prealbumin, mortality, and causespecific hospitalization in hemodialysis patients. Kidney Int 2005; 68: Sodium It is a mineral (metal) that is vital to normal body function Present in body fluids (extracellular) Reflex change in the volume of water 7

8 Sodium Control Narrow Concentration Range (Blood) Control by: Hormone production: Increase urine losses of Na + (BNP) Decrease urine losses of Na + (Aldosterone) Prevents water loses (ADH) Thirst control (1% increase of blood Na + ) H 2O Sodium Hyponatremia: deficient intake (rare), diarrhea, vomiting, excessive sweating, diuretics, Addison s Disease, CKD (Chronic Kidney Disease), CHF, Cirrhosis, increases of ADH (cancer, drug) Hypernatremia: dehydration, Cushing Syndrome, decrease of ADH Potassium Stimulate contraction (intracellular) Maintain a stable acid-base balance Maintain the normal function of neuromuscular tissue (heart) 8

9 Potassium Hypokalemia: dehydration, vomiting, diarrhea, deficient intake (rare) Hyperkalemia: excessive intake, acute or chronic kidney failure, Addison s Disease, injury to tissue, infection, diabetes, dehydration Glucose Simple sugar (carbohydrate) Insulin transport Glucose into the cell The main source of energy of the cell The brain and nervous system cells rely only on glucose Fasting Blood Glucose (ADA) 70 to 99 mg/dl 100 to 125 mg/dl Normal glucose tolerance Impaired fasting glucose (pre-diabetes) 126 mg/dl & above Diabetes 9

10 Glucose Hypoglycemia: adrenal insufficiency, alcohol, drugs (acetaminophen, anabolic steroids) extensive liver disease, hypothyroidism, insulin overdose, insulinomas, starvation Glucose Hyperglycemia: diabetes, excessive food intake, acromegaly, trauma, stroke, chronic renal failure, Cushing Syndrome, drugs (birth controls pills, diuretics, Salicylates, tricyclic antidepressants, dilantin), hyperthyroidism, pancreatic cancer, pancreatitis, IV* Glucose Monitoring Systems & POCT Caveats: Whole blood measurement* Error usually technique driven Correlates clinically with the serum measurements done at the laboratory 10

11 A1c Evaluates the average amount of glucose over the last 3 months Hb A + GLU RBC life is about 120 days HbA1c (irreversible) Used to: monitor diabetes treatment & screening and diagnosis of diabetes* *2010 ADA- Clinical Practice Guidelines A1c Screening & Diagnostic* Non- diabetic 4 % - 6 % Pre Diabetes 5.7 % - 6.4% Diabetes > 6.5 % Monitoring* Goal: < 7 % A1c test will not reflect temporary acute decrease or increase blood sugar ADA recommends testing: twice a year *2010 ADA- Clinical Practice Guidelines eag (estimated Average Glucose) It is a calculation A1c evaluates the average amount of glucose over the last 3 months eag = 28.7 x A1c 46.7 Example: A1c=6% eag=126 mg/dl eag should be included with every A1c result (patient friendly) 11

12 BUN It is a measurement of the amount of urea nitrogen in the blood Proteins NH 3 Urea (liver) Kidneys eliminate urea (impair kidney function will increase BUN levels) BUN Decrease* in: severe liver disease, malnutrition, overhydration, pregnancy Increase in: CKD, kidney failure, CHF, shock, stress, severe burns, dehydration, urinary obstruction, excessive protein catabolism Creatinine Creatine Creatinine (muscle) Creatine is use in muscle contraction & Creatinine is the waste product Depends on the amount of muscle (constant rate) 12

13 Creatinine Decrease* in: pregnancy, decrease of muscular mass Increase in: glomerulonephritis, pyelonephritis, acute tubular necrosis (drug or toxins), kidney stone, dehydration, CHF, diabetes, CKD Creatinine & egfr egfr is an estimated Glomerular Filtration Rate based on the value of the patient s serum creatinine, age, sex and race. In outpatients, egfr should be used as a helpful tool in screening for CKD. In inpatients or patients with acute renal failure egfr represents the GFR at the moment of the draw and should be used with caution. Phosphorous It is a mineral Phosphorus (P i )/Phosphate (PO 4-2 ) Absorbed by the intestine (diet) PO -2 4 roles: energy production, muscle function, nerves function, bone growth, and acid-base balance. Distribution: 70% to 80% bones and teeth 10% muscles 1% nerves 1% in blood The rest in cells (energy storage) 13

14 Phosphorous Decrease in: Malnutrition, Alcoholism, Severe Burns, Hypercalcemia, Hyperparathyroidism, Hypothyroidism, Hypokalemia, Rickets, Osteomalacia, Overuse of Diuretics and Chronic Antacid use Increase in: Kidney Failure, Hypoparathyroidism, Increase in dietary intake (soft drinks and pre-packaged foods) Ketoacidosis : high [treatment] low Calcium One of the most important minerals of our body 99% in bones Mostly bound to proteins (blood) Ca ++ (metabolically active) Calcium Hypocalcemia: low proteins*, Hypoparathyroidism, decrease intake, low Vit. D, low Mg, pancreatitis, alkalosis, malnutrition, bone disease, chronic renal failure Hypercalcemia: cancer (bone metastasis), hyperparathyroidism, sarcoidosis, bone break*, high proteins 14

15 Bibliography 1- Clarke, W. and Dufour, D. R., Editors ( 2006). Contemporary Practice in Clinical Chemistry: AACC Press, Washington, DC. 2- The National Kidney Foundation: Kidney Disease Outcomes Quality Initiative. Available online at through 3- Holland DC, Meers C, Lawlor ME, Lam M. Serial prealbumin levels as predictors of outcomes in a retrospective cohort of peritoneal and hemodialysis patients. Journal of Renal Nutrition, July 2001, 11(3). 4- Clinical Chemistry: Theory, Analysis, and Correlations. Kaplan L, Pesce A, Kazmierczak, eds. 4th ed. St. Louis: The C. V. Mosby Company; Clinical Guide to Laboratory Tests. 3rd ed. Tietz N, ed. Philadelphia: W.B. Saunders & Co; Wu, A. ( 2006). Tietz Clinical Guide to Laboratory Tests, 4th Edition: Saunders Elsevier, St. Louis, MO. Pp Henry's Clinical Diagnosis and Management by Laboratory Methods. 21st ed. McPherson RA and Pincus MR, eds. Philadelphia: 2007, Pg Lab Tests Online 9- ADA Clinical Practice Recommendations. Diabetes Care 28:S37-S42, Available online at Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. Burtis CA, Ashwood ER and Bruns DE, eds. 4th ed. St. Louis, Missouri: Elsevier Saunders;

16 Questions? Contact Information 171 Green Meadows Drive South Lewis Center, Ohio Phone: Fax: Thank you for participating in this webinar! 16