54-day old male infant Asian descent. First sign of jaundice appeared few weeks after birth Treatment sunlight exposure

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1 Assess lab values in a variety of patients Correlate lab results with a presumptive diagnosis Discuss further lab testing to confirm various diagnoses Stephanie Blackburn, MHS, MLS(ASCP) CM day old male infant Asian descent First sign of jaundice appeared few weeks after birth Treatment sunlight exposure 4 Subsequent physician visits, still jaundiced Treatment stop breastfeeding Jaundice continued, despite interventions Development of pale stools Day of life Test name Assay Instrument Result Reference (mg/dl) Range (mg/dl) 1 Neonatal Dbil Direct Spectr. 52 Bilirubin, Direct Diazo reaction 54 Bili Conjugated Direct Spectr. Reference Range source Vitros Manufacturer Roche Lab derived Vitros Lab derived 5 6 1

2 Biliary atresia Rare disease of liver and bile ducts Symptoms appear 2-8 weeks after birth Bile flow from liver to gall bladder is blocked Causes damage and scarring of liver Eventually leads to liver failure Most common cause of liver transplants in children Jaundice Most often 2-3 weeks after birth Dark urine Light colored stools Weight loss & irritability Unremarkable newborn screens ruled out metabolic disorders 7 8 Newborn conjugated bilirubin (reported as Neonatal Dbil ) of 0.5 mg/dl is inconsistent with diagnosis of biliary atresia Most infants with biliary atresia have slightly elevated newborn direct or conjugated bilirubin. Infant had increased AST, ALT, and GGT Normal abdominal ultrasound Liver biopsy showed fibrosis and bile duct proliferation, characteristic of biliary atresia Operative cholangiogram confirmed the diagnosis % infants evaluated for jaundice Most due to increased unconjugated bilirubin Treat with sunlight exposure Remove breastmilk 11 Few have increased conjugated bilirubin Indicates more serious situation requires prompt intervention 12 2

3 Examine bilirubin starting at birth Newborn total bilirubin Determine need for phototherapy Conjugated (Dbil, Direct) bilirubin If high at birth likely born with disease If high later possible acquired after birth This infant likely DID have high conjugated bilirubin levels at birth Overlooked due to two subtle (yet critical) details: 1. Result reported as Dbil, when conjugated bilirubin was assayed 2. Reference interval too broad for newborn conjugated bilirubin assays Unconjugated Degradation of RBCs Kernicterus Conjugated bilirubin Conjugated Hepatocytes process unconjugated bilirubin Excreted in stool Conjugates with monoglucuronide Conjugates with diglucuronide Delta bilirubin Conjugated bilirubin Issue #1: Lab reported Dbil result Actuality conjugated bilirubin assay performed Terms often used interchangeably Conjugates with monoglucuronide Conjugates with diglucuronide Delta bilirubin Both assays widely available but completely different! Measures different bilirubin fractions Two different technologies

4 Measures ALL conjugated bilirubin (and a little unconjugated) Chemical reaction with diazo dye quantification of azobilirubin over specified time Only measures mono- and diglucuronide Based on direct spectrophotometery on Vitros analyzer Absorbance spectrum can only quantify these two forms of bilirubin Issue #2: Lab used manufacturer s reference interval Establishing pediatric reference intervals challenging Direct methods differ lab to lab complicates having one reference range Conjugated should have little variation because it uses same reagent on same analyzer Manufacturer RR is too broad In clinical practice, a range of mg/dl calculated from 64,095 newborns ages 0-14 days Other hospitals derived RR of mg/dl Too small sample size by manufacturer? Broad RR reduce f(+) and increase specificity Direct bilirubin of 0.5 mg/dl within normal range Conjugated bilirubin outside normal range Theoretically, this error prevented the early diagnosis and treatment May delay or prevent liver transplant The early (slightly) elevated conjugated bilirubin would have been followed up at two-weeks Bilirubin likely would have been higher

5 25 55 year old male History: Multiple sclerosis Psoriasis Hypertension Spinal stenosis On multiple medications 26 Thyroid screen Markedly elevated thyroid hormones Appeared to be hyperthyroidism Patient displayed no symptoms of hyperthyroidism Ultrasound of neck normal sized thyroid with no nodules TT3 FT4 TSH (+)TSH binding-inhibiting Ab Firm diagnosis of Grave s Disease Thyroglobulin Negative thyroglobulin Ab Inconsistent with Grave s Disease Patient questioned He is taking 100mg dose of biotin, 3x/day, to treat MS Recent studies suggest the benefits of biotin for treatment of MS Patient stopped biotin for two weeks Thyroid function tests - NORMAL

6 Lab Test On biotin Off biotin Reference Range FT4 (ng/dl) > TT3 (ng/dl) > TSH (IU/L) TSH bindinginhibiting Ab (IU/L) 36 <1 <1.75 All abnormal thyroid tests are immunoassays that use streptavidin-biotin immobilizing system Streptovidin has very high affinity for biotin Makes for a very precise assay T3 Assay TSH Assay interfere-with-common-laboratory-tests interfere-with-common-laboratory-tests Vitamin H Component in normal diet Daily requirement ~30µg/day Supplements widely used in U.S. for hair and skin problems Available over-the-counter Dosages up to 10mg PTH Estriol/Estradiol ACTH Cortisol FSH/LH Testosterone Progesterone Vitamin D AFP BNP CK-MB C3/C4 Ferritin Prealbumin

7 37 75 year old female Arrive in ER History of Type I diabetes (IDDM) Presents with rapid respirations & decreased response to stimuli 38 Lab Test Result Reference Range Sodium (mmol/l) Potassium (mmol/l) Chloride (mmol/l) Bicarbonate (mmol/l) Glucose (mg/dl) BUN (mg/dl) Creatinine (mg/dl) ph pco2 (mmhg) po2 (mmhg) 79 >85 Urine glucose 3+ Negative Urine protein 2+ Negative Urine ketones 3+ Negative 39 Metabolic acidosis Due to DKA Appears to be some kidney involvement Patient treated with appropriate therapeutic regimen 40 Lab Test Result Reference Range Sodium (mmol/l) Potassium (mmol/l) Chloride (mmol/l) Bicarbonate (mmol/l) Glucose (mg/dl) BUN (mg/dl) Creatinine (mg/dl) ph pco2 (mmhg) po2 (mmhg) 90 >

8 Functions Regulates activity of muscle tissue Enzymatic reactions in digestion & metabolism Homeostasis 98% intracellular Serum chemistry results reflect extracellular K + levels Blood ph Catecholamines Activity of Na-K ATPase Insulin Exercise Physical condition ph K + shifts from cells to plasma Accumulation of K + in serum/plasma ph K + shifts from plasma into cells HCO 3 affects uptake of K + by cells Insulin enhances cellular uptake of K + returns plasma K + to normal level Renal disease Addison s disease Crush injuries Hemolytic conditions Thrombocytosis Metabolic/respiratory acidosis Initially yes Patient has DKA Following treatment no K+ should be normal instead it is elevated WHY? Patient also not exhibiting signs of hyperkalemia 47 Preanalytical conditions: Specimen collection Specimen handling BE CAREFUL can lead to misdiagnosis and inappropriate treatment Dehydration Often observed in elderly 48 8

9 Specimen collected by nurse, using needle and syringe Nurse inadvertently placed needle in EDTA tube first Realizing her mistake, she pulled back on the plunger to save what little blood she had, withdrew the needle, and then placed the blood in a lithium heparin tube A new specimen collected for chemistry profile (collected by lab s phlebotomist) K + was 5.1 mmol/l mos old male infant Born at term by elective Cesarean section Well baby visit Normal growth and development Unremarkable medical history Splenomegaly, no other notable findings Lab testing not performed due to grossly lipemic sample 52 Findings included: Multiple lipomas on left ear lobe Abdominal exam: non-distended, soft, non-tender abdomen with splenomegaly No hepatomegaly Abdominal ultrasound splenomegaly Large infant At birth: Weight 60 th percentile Length 80 th percentile Head circ 57 th percentile At 7 months: Weight 99 th percentile Length 81 th percentile Head circ 70 th percentile

10 Maternal grandmother: Hypertriglyceridemia (reportedly in the thousands before treatment) Hypercholesterolemia Previous pancreatitis 55 Assay Result Reference interval White Blood Cell count, x10 9 /L Hemoglobin, g/dl 8.4 (L) Hematocrit,% 28.4 (L) Partial thromboplastin time, s Prothrombin time, s International normalized ratio Fibrinogen, g/l Iron, µmol/l Transferrin, g/dl Iron binding capacity,µmol/l Ferritin, pmol/l Assay Result Reference interval Uric acid, mmol/l Total bilirubin, mg/dl 0.7 <1.2 Thyroid stimulating hormone, miu/l Free thyroxine, ng/dl Lipase, U/L Cholesterol, mg/dl 277 (H) <170 HDL cholesterol, mg/dl <6 (L) >35 LDL cholesterol, mg/dl 83 <110 Triglycerides, mg/dl 831 (H) <150 α-1-fetoprotein,ng/dl Developed 40 years ago Used to classify lipid disorders prior to National Cholesterol Education Program (NCEP) Multiple diagnostic criteria: Lipid concentrations Appearance of serum Lipoprotein electrophoresis 58 Endogenous hypertriglyceridemia Carbohydrate-induced Increased VLDL Exogenous hypertriglyceridemia Fat-induced Inability to break down chylomicrons

11 Type IV hyperlipidemia Lab testing on parents revealed: Mother normal lipid profile Father extremely elevated triglycerides Autosomal dominant Affects 1 in 300 people in U.S. Predominately in adults Accelerates formation of atherosclerotic plaques Often asymptomatic May present with colicky pain or failure to thrive Lipemic serum This infant presented with splenomegaly and xanthomas Continued with formula diet Supplement with fish oil to reduce triglyceride concentrations As he ages feed primarily low-fat foods At 1 year transition to nonfat milk Follow-up annually with pediatrician to monitor lipid profile As laboratory professionals, we play a critical role in patient care 65 We are often Sherlock Holmes Don t be afraid to speak up Our knowledge & experience is priceless! 66 11