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Page 1: Newborn Screening Historical, Ethical, Technological Aspects

Newborn ScreeningHistorical, Ethical, Technological Aspects

Nutrition 526November 9, 2009

Cristine M Trahms, MS, RDBeth Ogata, MS, RDLisa Sniderman King, CGC

Page 2: Newborn Screening Historical, Ethical, Technological Aspects

Blood Sample on GuthrieFilter Paper Card

First screen must be taken 24-48 hours of life regardless of feeding status or weight

Page 3: Newborn Screening Historical, Ethical, Technological Aspects

Unsatisfactory Specimens (Provided by the New York State Department of Health)

 

 

Clotted or Layered

Serum Rings

Specimen Not Dried Before Mailing

Supersaturated

No Blood

Diluted, Discolored, or Contaminated

Scratched or Abraded

Quantity Insufficient for Testing

Page 4: Newborn Screening Historical, Ethical, Technological Aspects

Criteria for Newborn Screening important condition acceptable treatment available facilities for diagnosis and treatment difficult to recognize early suitable screening test natural history known cost effective to diagnose and treat

Wilson & Jungner, 1968

Page 5: Newborn Screening Historical, Ethical, Technological Aspects

MS/MS -High Impact and High Throughput One disease, one test is not cost

effective Many diseases, one test is cost

effective MS/MS allows for rapid, simultaneous

analysis and detection of many disorders of amino acid, organic acid, and fatty acid metabolism.

Page 6: Newborn Screening Historical, Ethical, Technological Aspects

Mass Spectrometer 1

Data system correlates m/z 85 to its precursor ion’s mass and records the abundance of all precursors (parents of m/z 85)

CH3 R - COO CH3 +N - CH2 - CH - CH2 - COO - C4H9

CH3

Mass Spectrometer 2

3/16” blood spotdeproteinization

derivatization

+CH2 - CH - CH2 - COOH(m/z 85)

3.78e4 cps+Precursor (85): 0.65 min (10 scans) from AC 012700-07

% % MultiView -- © 1996, SCIEX, a division of MDS Health Group.% % Original concept:% Dr. Ron Bonner% Dr. Lyle Burton % % Development:% Dr. Lyle Burton % Yves Legault% Shengping Ma% % With the help of:% Dr. Victoria Barclay % Scott Champ% Rob McDermid%

260.0

295.0

316.2

347.0

372.0

403.2

426.4 442.6

459.2

482.2

300 350 400 450m/z, amu

5000

10000

15000

20000

25000

30000

35000

Inte

nsity

, cps

Data of all compoundswithin selected range

(250 - 500 m/z)

Data of product ionswith a mass of 85 only

Collision Cell

CH3 R - COO CH3 +N - CH2 - CH - CH2 - COO - C4H9

CH3

What is MS/MS ?

Page 7: Newborn Screening Historical, Ethical, Technological Aspects

Tandem Mass Spectrometry (MS/MS)

Compounds analyzed are amino acids & acylcarnitines Amino acids – PKU, MSUD,

Homocystinuria Acylcarnitine {Carnitine (vehicle)

+fatty acid} for identification of organic acidurias and fatty acid oxidation disorders.

Page 8: Newborn Screening Historical, Ethical, Technological Aspects

Amino Acid Disorders AA that are not used to make proteins are recycled by

their specific metabolic pathways. Enzymatic deficiencies in these pathways lead to various clinical phenotypes.

PKU – Phenylketonuria : severe perm MR MSUD – Maple syrup urine disease: dd, hallucinations,

ataxia HCY – Homocystinuria: connective tissue damage – joints,

heart, dd, psychiatric dist. CIT – Citrullinemia: risk of hyperammonemiadd, coma,

death ASA – Argininosuccinic acidemia: brittle hair, liver dis, dd TYR I – Tyrosinemia type I: acute or chronic liver disease,

liver cancer, neurologic pain crises.

Diagnosed by plasma amino acids, and/or urine amino acids, and/or urine organic acids (takes 2-5 days)

Page 9: Newborn Screening Historical, Ethical, Technological Aspects

Organic Acid Disorders Organic acids are breakdown products of protein and fatty

acid metabolism. Defects in their breakdown lead to (generally) Vomiting, metabolic acidosis, elevated ammonia in crises Dd, motor delay, ataxia, heart/kidney/pancreatic problems

IVA - Isovaleric acidemia GA I – Glutaric acidemia type I HMG – 3-OH 3-CH3 glutaric aciduria MCD – Multiple carboxylase deficiency MUT – Methylmalonic acidemia (mutase def) 3MCC – 3-Methylcrotonyl-CoA carboxylase deficiency Cbl A,B – Methylmalonic acidemia PROP – Propionic acidemia BKT – Beta-ketothiolase deficiency

Diagnosed by urine organic acids and/or plasma acylcarnitines.

Page 10: Newborn Screening Historical, Ethical, Technological Aspects

Fatty Acid Oxidation Disorders

Fatty acid disorders lead to impaired energy production. Hypoglycemia, cardiomyopathy, muscle weakness can be

seen

MCAD – Medium-chain acyl-CoA dehydrogenase deficiency VLCAD – Very long-chain acyl-CoA dehydrogenase deficiency LCHAD – Long-chain L-3-OH acyl-CoA dehydrogenase

deficiency TFP – Trifunctional protein deficiency CUD – Carnitine uptake defect

Diagnosed by plasma acylcarnitines and urine organic acids can be helpful.

Page 11: Newborn Screening Historical, Ethical, Technological Aspects

+Prec (85.10): 0.401 to 1.202 min from Sample 9 (BADER) of AC 101003 DATA.wiff (Turbo Spray... Max. 3.5e4 cps.

260 280 300 320 340 360 380 400 420 440 460 480 500m/z, amu

5%

10%

15%

20%

25%

30%

35%

40%

45%

50%

55%

60%

65%

70%

75%

80%

85%

90%

95%

100%

Re

l. Int. (%

)

*

* * * *

*

C2

100%

Inte

nsity

* internal standards

Control

+Prec (85.10): 0.401 to 1.202 min from Sample 8 (PATE) of AC 101003 DATA.wiff (Turbo Spray) Max. 3.8e4 cps.

260 280 300 320 340 360 380 400 420 440 460 480 500m/z, amu

5%

10%

15%

20%

25%

30%

35%

40%

45%

50%

55%

60%

65%

70%

75%

80%

85%

90%

95%

100%

Re

l. Int. (%

)

Inte

nsity

100%

*

* * *

*

*

MCAD

C2

C16

C8

C10:1C6

MS/MS Plasma Acylcarnitines

Page 12: Newborn Screening Historical, Ethical, Technological Aspects

Normal

C2*C3

*C4*

C8

*C12

*

C16*

VLCAD

Free Carnitine

*

* *

* *

*

C14:1C12 C18:1C16

* internal standards

VLCAD profileFree Carnitine

Page 13: Newborn Screening Historical, Ethical, Technological Aspects

MS/MS Plasma Amino Acids

Page 14: Newborn Screening Historical, Ethical, Technological Aspects

Acylcarnitine – VLCAD Deficiency

Page 15: Newborn Screening Historical, Ethical, Technological Aspects

Which Disorders to Screen For? NBS mandates are under state control

Some states screened for 3 diseases, others 40+

2002 Maternal and Child Health Bureau commissioned ACMG Analyze literature Develop consensus on which disorders Recommend a core panel to create

uniform NBS across all states.

Page 16: Newborn Screening Historical, Ethical, Technological Aspects
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Page 19: Newborn Screening Historical, Ethical, Technological Aspects
Page 20: Newborn Screening Historical, Ethical, Technological Aspects

Historical Harm (?) Early PKU screening led to cases of

overly restricted phe and/or implementation of diet prior to confirmation of diagnosis Today, diagnosis is quite rapid 40 years ago it took much longer so more

potential for harm However, no published evidence of

wide-spread physical/medical harm BUT the cases do underscore need for

expertise and resources for mgmt

Page 21: Newborn Screening Historical, Ethical, Technological Aspects

Whom do we see?1. Patients who need active

management Symptomatic at diagnosis Strong evidence of pathology if

untreated Examples: PKU, classic gal, MSUD, PA

etc.

Page 22: Newborn Screening Historical, Ethical, Technological Aspects

Whom do we see?2. Patients with disorders known to

pose risk but reduced penetrance ie. probably not everyone needs to be

treated HPHE, MCAD Both are/have mild ends of the

spectrum that have only been identified through NBS

MCAD mutation c.199 C>T Never seen in patients picked up

clinically

Page 23: Newborn Screening Historical, Ethical, Technological Aspects

Whom do we see?3. Patients who may not need any

management Disorders considered extremely rare

but seen in large numbers via NBS programs

Reported cases have significant morbidity

NBS pickups are mostly mild 3MCC, SCAD

Biochemical phenotype

Page 24: Newborn Screening Historical, Ethical, Technological Aspects

Proceeding with Caution(Reasons to be Thoughtful)

Proceeding with caution Not screening Core diseases vs secondary

targets/unintended targets What is reported vs withheld? Will we p/u untreatable conditions? What is the impact of false positives on

families? No long-term outcome data – consider

research paradigm Consider infrastructure needed for f/u

Page 25: Newborn Screening Historical, Ethical, Technological Aspects

Other Benefits to ScreeningFor disorders in which proven, effective

treatment is not available, or very new.

Consider non-medical benefits: Avoid the diagnostic odyssey Allow for reproductive decision making

before future children are born Allow for early access to clinical trials

for new therapies Emotional preparation for disease

Page 26: Newborn Screening Historical, Ethical, Technological Aspects

What Are We Screening For?

9 OA 5 FAO 6 AA 3 Hb Pathies

6 Others

CORE PANELIVAGA IHMGMCDMUT3MCCCbl A,BPROPBKT

MCADVLCADLCHADTFPCUD

PKUMSUDHCYCITASATYR I

Hb SSHb S/ßThHb S/C

CHBIOTCAHGALTHEARCF

Page 27: Newborn Screening Historical, Ethical, Technological Aspects

What Are We Measuring?Disorder 1° Marker 2° Marker Ratios

VLCADD C14:1 C14,C16,C18,C18:1 C14:1/C16

LCHADD C16OH C14,C14:1,C16:C18,C18:1,C18:1OH, C18OH C16OH:C16

TFP C16OH C14,C14:1,C16:C18,C18:1,C18:1OH, C18OH C16OH:C16

CUD C0 All carnitines (low)

PA C3 C2 C3/C0, C3/C2, C3/C16

MMAs C3 C4DC C3/C0, C3/C2, C3/C16

IVA C5 C5/C2, C5/C0, C5/C3

GA-1 C5DC C5DC/C8, C5DC/C16, C5DC/C5OH

BKT C5:1 C5OH C5OH/C8

HMG C5OH C6DC C5OH/C8

HCSD C5OH C3 C5OH/C8

CIT Cit Cit/arg

ASA Cit Asa Cit/arg, cit/phe, cit/tyr, asa/arg

TYR Suac Tyr

Page 28: Newborn Screening Historical, Ethical, Technological Aspects

Emma 13 months old Normal pregnancy and delivery Healthy Normal eating pattern, no allergies or intolerances Feb 2008: Vomited Saturday and 4-5 times throughout

the weekend No fever Sleeping for extended periods – parents concerned

but previous fever had same pattern. Parents gave Pedialyte

Page 29: Newborn Screening Historical, Ethical, Technological Aspects

Emma 4 ½ y brother, parents sick on

Sunday/Monday. Same symptoms Monday night 9:30 checked on E

Raspy breathing – thought respiratory problem but not worried

Tuesday morning 11am she was found motionless in her crib and pronounced dead at the scene

Page 30: Newborn Screening Historical, Ethical, Technological Aspects

Emma Autopsy revealed fatty changes to

liver Coroner requested newborn screening

blood spot be sent for acylcarnitine profile

Diagnostic for Very Long Chain Acyl-Co A Dehydrogenase Deficiency (VLCAD)

Page 31: Newborn Screening Historical, Ethical, Technological Aspects

VLCAD Disorder of long chain fatty acid

breakdown C14, C14:1 C16, C18 Normal beta oxidation occurs in

mitochondria

Page 32: Newborn Screening Historical, Ethical, Technological Aspects

Fatty Acid Oxidation

During times of fasting, fatty acids are primary substrate for energy production in liver, cardiac muscle and skeletal muscle

Brain uses ketones (produced by normal b-oxidation)

Page 33: Newborn Screening Historical, Ethical, Technological Aspects

Fatty Acid Oxidation

http://www.genomeknowledge.org/figures/saturatedbetao.jpg

Page 34: Newborn Screening Historical, Ethical, Technological Aspects

VLCAD Enzyme

VLCAD enzyme sits on inner mitochondrial membrane

Catalyzes first step of b-oxidation for C14-C20

Defect leads to impaired energy production during times of

fasting stress Accumulation of toxic long-chain acyl-CoA

intermediates within mitochondria Steatosis (fatty accumulation/degeneration)

seen in hepatic, cardiac and skeletal muscle

Page 35: Newborn Screening Historical, Ethical, Technological Aspects

VLCAD Presentations

Hypertrophic cardiomyopathy, with hypoglycemia and skeletal myopathy, lethargy, failure to thrive Usually present birth-5 months

Hypoglycemia, hepatomegaly, muscle weakness without cardiac manifestations Late infancy – older childhood

Muscle weakness/pain, rhabdomyolysis with exercise or illness. No hypoglycemia or cardiac Teens to adulthood

Page 36: Newborn Screening Historical, Ethical, Technological Aspects

Diet low in long-chain fats (Portagen, Monogen = 87%, 90% of fats as MCT)

Additional medium chain fats (MCT oil, walnut oil)

Carnitine 100 mg/kg/day Avoidance of fasting Treating illness with IV glucose

support

VLCAD TreatmentVLCAD Treatment

Page 37: Newborn Screening Historical, Ethical, Technological Aspects

VLCAD DiagnosisVLCAD Diagnosis

Newborn screening Plasma acylcarnitine profile Urine organic acids (should be

normal) DNA sequencing

Page 38: Newborn Screening Historical, Ethical, Technological Aspects

Zach Testing

Family referred to genetics by coroner Parents requested testing for older

brother Acylcarnitine ordered DNA sequencing of ACADVL gene

ordered

Page 39: Newborn Screening Historical, Ethical, Technological Aspects

Normal acylcarnitine profile

Page 40: Newborn Screening Historical, Ethical, Technological Aspects

Acylcarnitine – Zach 5 y.o.

C14:1

C16:1- nl

C14 C16 - nl

Page 41: Newborn Screening Historical, Ethical, Technological Aspects

Zach Testing

Reported: mild elevation of C14 and C14:1 with low free carnitine. VLCAD cannot be ruled out

Recommend supplementing with carnitine and retest in 1 week

Family left for Disneyland DNA testing results back before AC

repeat

Page 42: Newborn Screening Historical, Ethical, Technological Aspects

Zach Testing

Zach’s DNA testing reveal he is affected.

Family seen in BCG clinic, started on treatment.

Consent to obtain NBS blood spot obtained

Page 43: Newborn Screening Historical, Ethical, Technological Aspects

Acylcarnitine – Zach 5 y.o.

C14:1

C16:1- nl

C14 C16 - nl

C18 - nl

Page 44: Newborn Screening Historical, Ethical, Technological Aspects

Acylcarnitine – Zach newborn

C14:1

C14

C16

C16:1 C18

Page 45: Newborn Screening Historical, Ethical, Technological Aspects

Zach Clinical picture

5 y.o Healthy No symptoms of muscle weakness

CPK = 315U/L (35-230) No hepatomegaly

AST= 49 (5-41) ALT= 23 Bilirubin conj, unconj = normal (0.0, 0.4)

No evidence of cardiac involvement Has had several viral illnesses in his lifetime without

difficulty Once on carnitine, AC profile was classic for VLCAD

Page 46: Newborn Screening Historical, Ethical, Technological Aspects

Newborn Screening – A Team Effort

1. The Presumptive Positive PhaseDOH NBS Laboratory Personnel

Mike Glass, Sheila Weiss, John Thompson, Carol-Nucup-Villaruz, Charlene Adams, Jessica Dolle, many laboratory technologists

2. The Diagnostic Confirmation PhaseCHRMC Diagnostic Laboratory Personnel

Sihoun Hahn, Rhona Jack, Lisa Sniderman King, Cindy Gordon, Nancy McDowell Laura Mitchell, Diane Rebholz, Malcolm ReiderMonica Jensen, Ngoc-Diep Pham, Min Zhang

Page 47: Newborn Screening Historical, Ethical, Technological Aspects

Newborn Screening – A Team Effort

3. The Clinical Follow-up PhaseClinic Personnel

All previously screened disorders: (PKU, MCAD, gal, btd, msud, hcys):

UW: Ron Scott, Cris Trahms, Beth Ogata, Janie Heffernan, Jan Garretson, Stefanie Uhrich, Angie Fox

All expanded screening disorders (FAOs, OAs…etc): CHRMC: Lawrence Merritt, Michael Raff, Sihoun

Hahn, Sue Hale, Kelly McKean, Melissa Edwards, Lisa Sniderman King, Penny Schubert

Page 48: Newborn Screening Historical, Ethical, Technological Aspects

What Happens After a Positive

1. NBS Lab notifies all clinical f/u and key laboratory personnel of referral.

2. Laboratory technologists prioritize samples and collate results

Multiple tests (AA, OA, AC) on each kiddo

Interpreted together once all are completed

Uniform, concise reporting

Page 49: Newborn Screening Historical, Ethical, Technological Aspects

2008 Cases 58 total cases since Jan 51 since expanded NBS started (July 21) 8 true positives for targeted disorders (MCAD and PKU) 1 true positive for secondary disorder (CblC)

Elev C3 1° targets MMA/PA/CblA,B 38 FP/FPA – targeted disorder ruled out

False Positive Active Persistent elevations in ‘normal’ baby Carriers (ie. further testing needed) Benign forms (D/G galactosemia)

These are active because they require genetic counseling or lab repeats

They are reclassified as FP when case is closed False Positive

1 mom with low free carnitine Several D/G galactosemia A few VLCAD carriers

10 pending (waiting for samples) 2 Unknown

Page 50: Newborn Screening Historical, Ethical, Technological Aspects

2008 CasesNewborn Screening Cases per Month

02468

1012141618202224

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Month

Cas

es

True Positive

False Positive

Pending

Unknown


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