Genetics Visiting Professor (GVP) Grand Rounds

Presented by: AAP Chapter 3 and the Lower Hudson Valley Perinatal Network

(LHVPN)

Advances in Newborn Screening

David Kronn, MD, FACMG, FAAP Director, Inherited Metabolic Disease Center

Maria Fareri Children’s Hospital at Westchester Medical CenterAssociate Professor of Pediatrics

New York Medical College

• The Genetics Visiting Professorship is a competitive award of the American Academy of Pediatrics (AAP) Newborn Screening Program, and funded through a joint public/private partnership between the Maternal and Child Health Bureau/Health Resources and Services Administration, the National Coordinating Center for the Regional Genetics and Newborn Screening Service Collaboratives, housed at the American College of Medical Genetics, and the AAP.

Genetics Visiting Professorship

GVP: Partnership Between AAP and LHVPN

Lower Hudson Valley Perinatal Network (LHVPN) has the the goal of making sure all babies are born healthy. Together we work to advocate for and educate consumers and professionals about maternal, child and family health issues impacting the region.

The goals of the GVP program are:– Updates on what new genetic diseases have been added to the

newborn screen– Managing abnormal results (disease and carrier states) from the

newborn screen– Review of the primary care provider's role in caring for

newborns with genetic diseases diagnosed by newborn screen– Discussing newer genetic diagnostic techniques such as

microarray analysis

Summary Questions• What is Newborn Screening?• What role has New York played in the

development of Newborn Screening?• How do we choose which diseases to screen?• What are the demographics of Newborn

Screening in New York State?• What have been the consequences of

expanding Newborn Screening?• What can we expect form Newborn Screening in

the future?• What is tandem mass spectroscopy?

What is Newborn Screening?

“The goal of newborn screening is early detection of children at increased risk for selected metabolic or genetic diseases so that medical treatment can be promptly initiated to avert metabolic crises and prevent irreversible neurological and developmental sequelae.”

Newborn Screening in New York -A Guide for Health Professionals 1991

Rationale for Treatment of Genetic Disease

Newborn Screening

Early Diagnosis

Intervention Prior to Onset of Symptoms

Prevention of Disease Progression

Phenylketonuria (PKU)

• Frequency about 1 in 10,000 births in Caucasian population

• Phenylalanine is neurotoxic at high levels• Defect in enzyme phenylalanine hydroxylase• 1 to 2 % of cases due to defect in

dihydropteridine reductase (DHPR) or in the synthesis of biopterin

• Treatment is for life• Maternal PKU effects

Time Line for Specimen Collection

Day of Life 1 2 3 4 5

SpecimenQuality

A B C C C

Age (hours) Birth 24 48 72 96

Newborn Screening: Early Discharge

Missing the diagnosis

Threshold Level

AbnormalMetaboliteLevel

Time

Algorithim for Newborn Screening

Newborn Screening Results

Screen Negative BorderlineScreen Positive

Referral to Specialty Center

Case Complete Repeat Specimen

Negative Positive

Negative Positive

Specific evaluation for confirmation of diagnosis

What role has New York played in the development of Newborn

Screening?

Dr. Robert Guthrie

(1916-1995)

History of Newborn Screening in New York State• 1930’s George Jervis at Letchworth Village State School in Thiells, NY

identified 50 clients with metal retardation attributed to PKU

• 1963 Robert Guthrie, microbiologist-pediatrician at State University of New York, Buffalo, devised simple inexpensive which allowed screening for PKU

• 1964 Robert Guthrie coordinated a 29 state pilot study of screening in 400,000 newborns for PKU, proved so successful that many states instituted newborn screening immeadiately

• 1965 New York State law for newborn screening, Public Health Law 2500a went into effect, mandating that every newborn be screened for PKU

• 2002 Introduction of MS/MS technology for the testing of PKU, MSUD, Homocystinuria, and MCAD Deficiency

• 2006 Addition of Krabbe Disease to the panel

How do we choose which diseases to screen?

The Cardinal Principles of Screening

• The disorder has a relatively high incidencehigh incidence so that the cost per diagnosed individual is reasonable

• An effective and not overly expensive treatment is available

•A relatively inexpensive screening test is available that is suitable for high volume testing (preferably automatable)

•The screening test has a very high sensitivity ( i.e. a very low rate of false negatives) and high specificity ( i.e. low rate of false positives which require expensive follow-up)

Some of the basic criteria for determining which inherited disorders for newborn screening include:

Criteria for Newborn Screening

• Disorder produces irreversible damage before onset of symptoms

• Treatment is effective if begun early

• Natural history of disorder is known

MS/MS ACMG Recommended Panel Acylcarnitines Amino acids

9 OA 5 FAO 6 AA 3 Hgbpathies 6 Others

CORE PANEL

IVAGA IHMGMCDMUT

3MCCCbl A,BPROPBKT

MCADVLCADLCHAD

TFPCUD

PKUMSUDHCYCITASA

TYR I

Hb SSHb S/ßThHb S/C

CHBIOTCAHGALTHEAR

CF

SECONDARY TARGETS

6 OA 8 FAO 8 AA 1 Hb Pathies 2 Others

Cbl C,DMALIBG

2M3HBA2MBG3MGA

SCADGA2

M/SCHADMCKATCPT IICACTCPT IADE RED

HYPER-PHE TYR II

BIOPT (BS)ARG

TYR III BIOPT (REG)

MET CIT II

Var Hb GALK GALE

What are the Demographics of Newborn Screening?

New York State Newborn Screening Program 1965-2007

Disorder Testing Initiated

Infants Tested Confirmed Cases

Disease Incidence

PKU 1965 11.54 Million 538 1:21,000

Galactosemia 1968 10.59 Million 185 1:57,000

MSUD 1968 10.59 Million 40 1:265,000

Homocystinurua 1975 8.62 Million 26 1:334,0000

Homozygous Sickle Cell

1975 8.62 Million 4683 1:1,840

Primary Hypothroidism

1978 7.89 Million 3944 1:2,000

Biotinidase Deficiency

1987 5.07 Million 58 1:87,000

U.S. Newborn Screening – 2001Using or Close to Using MS-MS

Screening

Not Screening

Optional or Moving Quickly

U.S. Newborn Screening – 2001Using or Close to Using MS-MS

Screening

Not Screening

Optional or Moving Quickly

U.S. Newborn Screening – 2001Using or Close to Using MS-MS

Screening

Not Screening

Optional or Moving Quickly

U.S. Newborn Screening – 2008Using or Close to Using MS-MS

Screening

Not Screening

Optional or Moving Quickly

What have been the consequences of expanding

Newborn Screening?

Positive Consequences

• Early detection of potentially life threatening conditions

• Early treatment and prevention of sequelae

Negative Consequences

• High False Positive Rates– Impact on families– Impact on health system

• Uncovering variant conditions with unclear pathogenesis

• Detection of carriers

Potential Impact of False Positives

• USA 4,100,000 births per year

• 1:2,400 confirmed diagnoses

• 10 - 20 False Positives per diagnosis

• 25,000 – 50,000 False Positives

• Lets look at New York State 2007 Data– Review 2007 report

Why Parents May Be Vulnerable

• Peak health worries occur in the 25-34 age group

• In general young people worry more than older people

• Younger people more active and problem focused

• Older people more passive and emotion focused

Lindsay et al., Worry over the lifespan. Psychological Medicine 2006; 1-9

A Few Examples of Negative Consequences

• “It was scary and when I found out my daughter was fine I felt like we’d gone through a lot for nothing.”

• “I was upset as they (the physicians) were elusive about why my child had to return for a repeat test.”

• “The pediatrician said that a blood test was needed, but she didn’t know what it was for”

• “We were told ‘no news is good news’. They never called back with the results”

We increasingly need to be aware of the complexities of testing and to communicate this sensitively to our patients

Medium Chain Acyl-CoA Dehydrogenase Deficiency

Medium Chain Acyl CoA Dehydrogenase Deficiency

• Most common FAOD, incidence up 1 in 10,000

• Exclusively hepatic presentation - most frequently seen as hypoketotic hypoglycemia provoked by fasting

• May be a history of sibling death

• Affected individuals usually normal until an episode occurs

•Newborn screening by ms/ms with elevated octanoylcarntine

• Specific abnormalities seen on urine organic acid analysis, acylcarnitine, plasma free fatty acid and acylglycine analysis

• MCAD gene has been cloned to chromosome 1p31. A single

mutation at nucleotide 985, A to G accounts for 90% of

disease carrying alleles.

• Treatment revolves around prevention of fasting, the use of carnitine remains controversial

MCAD Deficiency: Octanoylcarntine Peak

MCADD Screening

Method: Octanoylcarnitine level by Tandem Mass Spectrometry

Newborn Screening Consequences

• Detection of Unaffected Carriers– ACMG recommendation on carrier screening

advises waiting to test until individuals can consent themselves for testing, provided the result has no bearing on health to that point.

– No clear policy on how to deal with these patients

– A major concern for Cystic Fibrosis• Look at 2007 report again!

Cautionary Tales!

Expanded Screening Problems

• Overall we seem to be dealing with lots of false positives

• Are SCAD and 3-MCC Diseases?

• Low C0 levels from the NICU

Newborn Screening Consequences – Additional Concerns

• Patients born in adjoining states may not have had access to the same expanded screening

• Siblings born in different states and different countries

• Siblings born before and after the expansion of newborn screening

• The demographic on the newborn screening card can sometimes be incorrect and lead to delays in locating patients for follow up testing

What can we expect form Newborn Screening in the future?

Krabbe Disease

Infantile Krabbe Disease

• Globoid cell leukodystrophy• Autosomal recessive disorder• Incidence ~1/100,000• Enzyme defect lysosomal galactocerebrosidase• Inability to degrade glycolipids found almost exclusively

in myelin• Clinically presents with dystonia (lead-pipe) rigidity of the

limbs and abnormal posturing) from about 6 months • Patients have irritability, poor feeding, motor regression

and seizures. • MRI: White matter changes and calcification particularly

affecting the basal ganglia• Death usually by two years of age.

Newborn Screening for Krabbe Disease

• Measurement of artificial product by ESI-MS/MS

• Diagnosis by enzyme analysis and DNA analysis

• Additional studies to confirm diagnosis– Brain MRI, CSF Protein, EEG, Neuro Eval.

• Treatment by Umbilical-Cord Blood Transplantation

• Long-term follow-up required

Krabbe Disease Screening - Concerns

• Screening– What is the false positive rate? It appears high– Does the burden of disease warrant screening?

• Diagnosis– Can we differentiate between infantile and adult onset

forms of the disease?– Will false positives who turn out to be carriers require

genetic counseling and family studies?• Treatment

– Can a HLA match be found for every patient screened positive?

– What is the longterm outcome of treatment?– Who will pay?

Krabbe Disease

Update as of December 2008– Over 80 referrals for low enzyme activity– Majority of patients have low levels on repeat but

above that expected for affected patients majority due to polymorphisms in the gene.

– Two patients so far have been identified with infantile Krabbe Disease and have been transplanted, one patient died of transplant complication

– Four other patients have enzyme assays suggesting juvenile or adult onset disease, they are all stable at this point

Future Newborn Screening Disorders – the latest new kids on the block• Lysosomal Storage Disorders

– Enzyme Replacement Therapy and Bone Marrow/ Umbilical Cord Cell Transplants more readily available.

• Peroxisomal Disorders– Adrenoleukodystrophy. Studies have shown the

benefit of Lorenzo’s Oil in presymptomatic individuals

• SCID– Clear benefit from transplantation

What is Tandem Mass Spectrometry?

What does MS/MS offer?

•Increased specificity, decreased false positives

•One test many diseases

•Many diseases do not meet the criteria for Newborn screening,but public opinion and availability of technology warrant offering testing for the larger group of diseases.

Mass Spectrometry 101Mass Spectrometry 101

TMS

Source Analyzer

First Mass Analyzer

Separation by molecular weight and charge - m/z

Collision cell

Fragmentation in inert gas chamber

Selective massmeasurement

Second Mass Analyzer

Note: Acylcarnitine analysis by loss of butyl ester, common 85mw fragment Amino acid analysis by loss of neutral molecule 102mw Different scan function can be produced in series

Mass spectrometry

CH3COCH3CH3COCH3

Sample Inlet

Sample Inlet

CH3+COCH3CH3+COCH3

Ionization& Adsorption

of Excess Energy

Ionization& Adsorption

of Excess Energy

Mass AnalysisMass Analysis

CH3C+OCH3CH3C+OCH3

+COCH3+COCH3

+CH3+CH3

+COH+COH

Fragmentation(Dissociation)Fragmentation(Dissociation)

DetectionDetection

Fragmentation of butylated Phenylalanine

H

H H

HH

CH2

CHH3N+ COOC4H9

60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210m/z0

100

%

120

103

939177

Normal amino acid profileNormal amino acid profile

140 160 180 200 220 240 260 280m/z0

100

%

140 160 180 200 220 240 260 280m/z0

100

%

d3-Leud3-Leu

d4-Alad4-Ala

d3-Metd3-Met

d5-Phed5-Phed6-Tyrd6-Tyr

d8-Vald8-Val

GlyGly

SerSer

ProPro

GluGlu

Deuterated internal standards for QuantificationDeuterated internal standards for Quantification

140 160 180 200 220 240 260 280m/z0

100

%

0

100

%

140 160 180 200 220 240 260 280m/z0

100

%

0

100

%

NormalNormal

PKUPKU

LeuLeu

d3-Leud3-Leu

d4-Alad4-AlaAlaAla

PhePhe

TyrTyr

MetMetd3-Metd3-Met

d5-Phed5-Phe

d6-Tyrd6-Tyr

PhePhe

Normal vs PKUNormal vs PKU

Elevated PhenylalanineElevated Phenylalanine

Conclusions and More Concerns

•New technology developments have allowed for the expansion of newborn screening - MS/MS

•Public opinion has made newborn screening a legislative initiative

•Some of these diseases do not meet the classical model of a screened disease

•Further pilot programs are needed to validate the technology

•Who will pay for all the follow-up?

•Does the horizon bring screening for even more diseases?

Final Thoughts

• The expansion of newborn screening has become a political mandate and has in large part been patient directed

• The pathology and long term outcome for some of these diseases is still unclear

• Ruling out a disease can be very expensive• There is no MS/MS available in New York

State for follow-up• TMS is here to stay!

Abnormal Newborn Screening Results• Contact:

– To obtain NY State Newborn Screening Results for your patients call (800) 535-3079

– To register call (518) 473-7552

• Maria Fareri Children’s Hospital at Westchester Medical Center is the NY State designated Newborn Screening Referral Center– Endocrine Disorders

• Endocrine Center (914) 366-3400– Hemoglobin Disorders

• Hemoglobinopathy Center - (914) 347-6970– Genetic Disorders/Cystic Fibrosis

• Cystic Fibrosis Center – (914) 493-7585 – Metabolic Disorders

• Inherited Metabolic Disease Center - (914) 304-5300

– HIV• Infectious Diseases Center – (914) 493-8333

For reference see links on www.lhvpn.net/newbornscreening

New Emerging Technologies• Microarray is now replacing individual

FISH and subtelomere analysis “molecular chromosomes”

• Molecular Screening is moving towards full sequencing of genes

• Gene identification in silico as a result of the human genome project

• Advances in therapeutics is driving the progress in newborn screening– If you can treat it, we should screen for it!

GVP GranteesThe LHVPN provides:

– Perinatal Health Education Materials Health education brochures available free of charge to distribute to clients and the community.

– Perinatal Health Education Sessions Community based education and information updates on issues that affect the health of mothers, fathers, babies and families. These sessions can be tailored to meet unique needs and are conducted upon request.

– Tri-annual Education & Networking Conferences Perinatal health related education for professionals who work with or on the behalf of women, children, men and families.

– Perinatal Health Speakers’ Bureau - Local experts available to deliver broad based provider and consumer education focusing on maternal, child and family health issues, racial and ethnic disparities, intersection of chronic disease and perinatal health, cultural competence, and life course as it impacts perinatal health. (We are recruiting local experts)

Visit us at: www.LHVPN.netContact us at: info@lhvpn.net or 914-493-6435

Through the national AAP, Chapter 3 provides:

– Fact sheets, Policy statements, Parent resources, State resources and tools for practitioners regarding genetics conditions and newborn screening.

– On our website (ny3aap.org) is a link to the National Center of Medical Home Initiatives for Children with Special Needs (www.medicalhomeinfo.org) which is an AAP initiative sponsored by the Maternal and Child Health Bureau of the Department of Health and Human Services.

– National Center of Medical Home Initiatives for Children with Special Needs (contact at: medical_home@aap.org) has a wealth of information regarding genetics conditions, screening policies, state specific initiatives, etc.

– Chapter 3 coordinated the Visitor Professorship with the LHVPN.

Visit us at: www.NY3AAP.orgContact us at: jgeslani@aapdistrictii.org or 516-326-0310

Santa says:“You’ve tested positive for the naughty gene”

AcknowledgementsAAP

Andrew D. Racine, MD, PhD, AAP, Chapter 3

Brenda Amos-Lewis

Ginny Chanda

Holly Griffin

Wadsworth Center/NYS Department of Health

Katharine B. Harris, MBA

Sarah Lawrence College

Caroline Lieber, MS, CGC

LHVPN

Cheryl Hunter-Grant, LMSW, CLC

Lorraine Anglin, MPH

Jeet Lund

Michelle Gordon

MFCH

Heather Brumberg, MD, MPH

David Kronn, MD

MOD

Diane M. Ashton, MD, MPH

Dionne A. Durant, LMSW

Sue Rose

Funded in part by grants from the AAP and NYS Department of Health/Division of Family Health

Please remember to hand in your post-test/evaluations. Thank you.