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.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

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.54-day old male infant 3 .Asian descent

.First sign of jaundice appeared few weeks after birth . Treatment  sunlight exposure

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.Subsequent physician visits, still jaundiced Day Test name Assay Instrument Result Reference Reference of (mg/dL) Range source . Treatment  stop breastfeeding life (mg/dL) 1 “Neonatal Dbil” Direct Vitros 0.5 0.0-0.6 Manufacturer Spectr. .Jaundice continued, despite interventions 52 “, Direct” Diazo Roche 5.54 0.0-0.4 Lab derived reaction .Development of pale stools 54 “Bili Conjugated” Direct Vitros 4.7 0.0-0.2 Lab derived Spectr.

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1 .Biliary atresia .Jaundice . Rare disease of and bile ducts . Most often 2-3 weeks after birth . Symptoms appear 2-8 weeks after birth . Bile flow from liver to gall bladder is blocked .Dark . Causes damage and scarring of liver .Light colored stools . Eventually leads to liver failure . Most common cause of liver transplants in children .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 .Infant had increased AST, ALT, and GGT diagnosis of biliary atresia .Normal abdominal ultrasound .Liver biopsy showed fibrosis and bile duct Most infants with biliary atresia have slightly proliferation, characteristic of biliary atresia elevated newborn direct or conjugated bilirubin. .Operative cholangiogram confirmed the diagnosis

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.15% infants evaluated for jaundice

.Most due to increased unconjugated bilirubin . Treat with sunlight exposure . Remove breastmilk

.Few have increased conjugated bilirubin . Indicates more serious situation – requires prompt intervention 11 12

2 .Examine bilirubin starting at birth .This infant likely DID have high conjugated .Newborn total bilirubin bilirubin levels at birth . Determine need for phototherapy .Overlooked due to two subtle (yet critical) details: .Conjugated (Dbil, Direct) bilirubin 1. Result reported as “Dbil”, when conjugated bilirubin . If high at birth  likely born with disease was assayed . If high later  possible acquired after birth 2. Reference interval too broad for newborn “conjugated” bilirubin assays

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Conjugated • Degradation of RBCs bilirubin Unconjugated • Kernicterus

Conjugates with • Hepatocytes process Conjugates with Delta bilirubin Conjugated unconjugated bilirubin monoglucuronide diglucuronide • Excreted in stool

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Conjugated bilirubin .Issue #1: Lab reported “Dbil” result . Actuality  “conjugated” bilirubin assay performed .Terms often used interchangeably

Conjugates with .Both assays widely available – but completely Conjugates with Delta bilirubin monoglucuronide diglucuronide different! . Measures different bilirubin fractions . Two different technologies

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3 .Measures ALL conjugated .Only measures mono- and bilirubin (and a little diglucuronide unconjugated)

.Based on direct .Chemical reaction with spectrophotometery on Vitros diazo dye  quantification analyzer of azobilirubin over . Absorbance spectrum can only specified time quantify these two forms of bilirubin

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.Issue #2: Lab used manufacturer’s .Manufacturer RR is too broad reference interval . In clinical practice, a range of 0.0-0.3 mg/dL calculated from 64,095 newborns ages 0-14 .Establishing pediatric reference intervals days challenging . Other hospitals derived RR of 0.0-0.2 mg/dL . “Direct” methods differ lab to lab – complicates having one reference range .Too small sample size by manufacturer? . “Conjugated” should have little variation .Broad RR reduce f(+) and increase because it uses same reagent on same specificity analyzer

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.“Direct” bilirubin of 0.5 mg/dL within normal range .Theoretically, this error prevented the early .“Conjugated” bilirubin outside normal range 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

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4 .55 year old male 25 .History: . Multiple sclerosis . Psoriasis . Hypertension . Spinal stenosis .On multiple medications

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.Thyroid screen .↑↑↑ TT3 . Markedly elevated thyroid hormones .↓↓↓ FT4 . Appeared to be hyperthyroidism .↓↓ TSH .(+)TSH binding-inhibiting Ab .Patient displayed no symptoms of hyperthyroidism .Ultrasound of neck  normal sized thyroid with no nodules .Firm diagnosis of Grave’s Disease

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.↓ Thyroglobulin .Patient questioned… .Negative thyroglobulin Ab . He is taking 100mg dose of biotin, 3x/day, to treat MS

. Recent studies suggest the benefits of biotin for treatment .Inconsistent with Grave’s Disease of MS

.Patient stopped biotin for two weeks . - NORMAL

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5 Lab Test On biotin Off biotin Reference Range FT4 (ng/dL) >7.8 1.4 0.9-1.8 .All abnormal thyroid tests are immunoassays that TT3 (ng/dL) >650 160 60-181 use streptavidin-biotin immobilizing system

TSH (IU/L) 0.02 0.78 0.4-5.0 . Streptovidin has very high affinity for biotin . Makes for a very precise assay TSH binding- 36 <1 <1.75 inhibiting Ab (IU/L)

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T3 Assay TSH Assay

33 34 https://www.healio.com/endocrinology/thyroid/news/print/endocrine-today/%7B0ff7371d-93a3-4865-b502-60fde9c98122%7D/high-dose-biotin-supplement-can- https://www.healio.com/endocrinology/thyroid/news/print/endocrine-today/%7B0ff7371d-93a3-4865-b502-60fde9c98122%7D/high-dose-biotin-supplement-can- interfere-with-common-laboratory-tests interfere-with-common-laboratory-tests

.Vitamin H . PTH . .Component in normal diet . Estriol/Estradiol . AFP .Daily requirement ~30µg/day . ACTH . BNP .Supplements widely used in U.S. for hair and skin . . CK-MB problems . FSH/LH . C3/C4 .Available over-the-counter . Testosterone . . Dosages up to 10mg . Progesterone . Prealbumin

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6 .75 year old female 37 .Arrive in ER .History of Type I diabetes (IDDM)

.Presents with rapid respirations & decreased response to stimuli

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Lab Test Result Reference Range Sodium (mmol/L) 128 136-145 Potassium (mmol/L) 5.8 3.5-5.3 Chloride (mmol/L) 90 99-109 .Metabolic acidosis (mmol/L) 12 22-28 . Due to DKA (mg/dL) 650 70-100 .Appears to be some involvement BUN (mg/dL) 30 12-16 (mg/dL) 1.4 0.6-1.2 pH 7.22 7.35-7.45 .Patient treated with appropriate therapeutic pCO2 (mmHg) 30 32-45 regimen pO2 (mmHg) 79 >85 Urine glucose 3+ Negative Urine protein 2+ Negative Urine ketones 3+ Negative 39 40

Lab Test Result Reference Range Sodium (mmol/L) 138 136-145 Potassium (mmol/L) 7.2 3.5-5.3 Chloride (mmol/L) 100 99-109 Bicarbonate (mmol/L) 22 22-28 Glucose (mg/dL) 140 70-100 BUN (mg/dL) 19 12-16 Creatinine (mg/dL) 1.2 0.6-1.2 pH 7.36 7.35-7.45 pCO2 (mmHg) 40 32-45 pO2 (mmHg) 90 >85

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7 .Functions . pH . Regulates activity of muscle tissue .Catecholamines . Enzymatic reactions in digestion & . Homeostasis .Activity of Na-K ATPase .98% intracellular .Insulin .Exercise + .Serum chemistry results reflect extracellular K .Physical condition levels

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.↓ pH  K+ shifts from cells to plasma .Renal disease + . Accumulation of K in serum/plasma .Addison’s disease + .↑ pH  K shifts from plasma into cells .Crush injuries . HCO affects uptake of K+ by cells 3 .Hemolytic conditions .Thrombocytosis .Insulin enhances cellular uptake of K+  returns plasma K+ to normal level .Metabolic/respiratory acidosis

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.Preanalytical conditions: . Specimen collection .Initially…yes . Specimen handling . Patient has DKA BE CAREFUL  can lead to misdiagnosis and .Following treatment…no inappropriate treatment . K+ should be normal – instead it is elevated – WHY? . Patient also not exhibiting signs of hyperkalemia .Dehydration . Often observed in elderly 47 48

8 .Specimen collected by nurse, using needle and .A new specimen collected for chemistry profile syringe (collected by lab’s phlebotomist) . Nurse inadvertently placed needle in EDTA tube first . K+ was 5.1 mmol/L . 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

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.6-mos old male infant 51 .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

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.Large infant .At birth: .Findings included: . Weight 60th percentile th . Multiple lipomas on left ear lobe . Length 80 percentile th . Abdominal exam: non-distended, soft, non-tender . Head circ 57 percentile abdomen with splenomegaly .At 7 months: . No hepatomegaly . Weight 99th percentile . Length 81th percentile . Head circ 70th percentile .Abdominal ultrasound  splenomegaly

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9 Assay Result Reference interval .Maternal grandmother: White Blood Cell count, x109/L 16.6 6-17.5 . Hypertriglyceridemia (reportedly “in the thousands” Hemoglobin, g/dL 8.4 (L) 10.5-13 before treatment) Hematocrit,% 28.4 (L) 34-40 Partial thromboplastin time, s 39 35.1-46.3 . Hypercholesterolemia Prothrombin time, s 13.3 11.5-15.3 . Previous pancreatitis International normalized ratio 1.0 0.86-1.22 Fibrinogen, g/L 3.62 0.82-8.83 Iron, µmol/L 39.2 7.2-44.8 , g/dL 2.89 2.03-3.6 Iron binding capacity,µmol/L 64.6 17.9-71.6 Ferritin, pmol/L 322 16-615 55 56

Assay Result Reference interval , mmol/L 0.178 0.065-0.33 .Developed 40 years ago Total bilirubin, mg/dL 0.7 <1.2 . Thyroid stimulating hormone, mIU/L 2.25 0.35-5.0 Used to classify lipid disorders prior to National Free thyroxine, ng/dL 1.18 0.8-1.6 Education Program (NCEP) , U/L 58 8-78 Cholesterol, mg/dL 277 (H) <170 HDL cholesterol, mg/dL <6 (L) >35 .Multiple diagnostic criteria: LDL cholesterol, mg/dL 83 <110 . Lipid concentrations Triglycerides, mg/dL 831 (H) <150 . Appearance of serum α-1-fetoprotein,ng/dL 87.0 8-87 . Lipoprotein electrophoresis

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Endogenous hypertriglyceridemia

• Carbohydrate-induced • Increased VLDL

Exogenous hypertriglyceridemia

• Fat-induced • Inability to break down chylomicrons

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10 .Type IV hyperlipidemia .Autosomal dominant .Affects 1 in 300 people in U.S. .Lab testing on parents revealed: .Predominately in adults . Mother – normal .Accelerates formation of atherosclerotic plaques . Father – extremely elevated

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.Often asymptomatic .Continued with formula diet .May present with colicky pain or failure to thrive .Supplement with fish oil to reduce .Lipemic serum concentrations .As he ages  feed primarily low-fat foods

.This infant presented with splenomegaly and .At 1 year  transition to nonfat milk xanthomas .Follow-up annually with pediatrician to monitor lipid profile

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.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!

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