NEWBORN SCREENING
Hana Vinohradská,M.D.
Department of Clinical Biochemistry
University Hospital Brno
1
What´s the newborn screening?
• The nationwide newborn screening (NS)
= preventive program of testing newborns for
increased risk of certain rare diseases
• NS tests are done by measuring metabolites in
samples of whole blood collected on special filter
paper („newborn card“ or „Guthrie card“) – analysis
of dry blood spots
2
Test card
3
History
• NS debuted in US in 1960
• Robert Guthrie (1916 – 1995)
• American microbiologist, developed a
simple method using a bacterial
inhibition assay that could detect high
levels of phenylalanine in blood
shortly after a baby was born.
• Guthrie also used the collection of
blood on filter paper which could be
easily transported.
4
History of NS in the Czech Republic
• 1975 - Phenylketonuria
• 1985 - Congenital hypothyroidism
• 2006 - Congenital adrenal hyperplasia
• 2009 - Cystic fibrosis and 9 additional metabolic diseases
• 2016 – further expansion of NS program (5 diseases:
argininemia, citrulinemia, 2 types of homocystinuria,
biotinidase deficiency)
At present there are 18 diseases tested in the Czech Republic.
NS program is covered by health insurance
5
NS Europe - 2015
•Zdroj: Therell BL et all: Current status of newborns screening worldwide: 2015. Seminars
in Perinatology 2015;39: 171-87
6
Methods of analysis
• Fluoroimunoassays (method DELFIA)
– congenital hypotyreoidism (TSH)
– congenital adrenal hyperplasia (17 OHP)
– cystic fibrosis (IRT)
• Tandem mass spectrometry (MS/MS)
– phenylketonuria and other disturbances of amino acid
metabolism (aminoacids)
– disorders of fatty acid oxidation (acylcarnitines)
• Molecular techniques
- second step of NS CF
7
Automatic analyzer AutoDELFIA
8
Tandem mass spectrometer
9
Newborn screening Laboratories
in the Czech Republic
For immunoanalytic method
• University Hospital Kralovské Vinohrady, Prague
• University Hospital, Brno
For tandem mass spectrometry
• General University Hospital, Prague
• University Hospital, Olomouc
10
Sample collection
• At the age of 48-72 hours after birth several drops of
capillary blood from the heel of the child are sampled on
a special paper (newborn card)
• After the collection of blood it has to dry well, avoid
contamination
• These cards are sent for analysis to the screening
laboratories
11
Sample collectionSample collection
12
Screening results
Evaluation of results – cut off = limit value
• Negative result – no suspicion for any the screened disease
• Positive result – indicates only increased risk of a disease
→ It is necessary to confirm this positive result, usually
by use further laboratory tests
13
Results of NS in the Czech Republic 2010-2018
14
CH 334
PKU/HPA 184
CF 150
CAH 84
MCADD 43
LCHADD 13
VLDADD 5
GA I 5
IVA 5
MSUD 5
CPT I 0
CPTII/CACT 0
ARG * 0
CIT * 0
BTD * 29
CBS * 1
MTHFR * 0
Total 858
* Diseases included to NS program since June 1st, 2016
Case – positive NS CF
• newborn – birth in term, birth weight 3800g
• results of NS:
 TSH ˂ 2,5 mIU/L →NS CH negative
 17OHP = 16 nmol/L → NS CAH negative
 IRT = 230 ng/mL ˃ cut off → molecular tests
 2 mutations in CFTR gene [F508del]+[F508del]
 sweat test – positive, Cl = 106 mmol/L (cutt off 30)
 dg. CF positive
15
Case – positive NS CAH
• newborn – birth in term, birth weight 3350g
• results of NS:
 TSH ˂ 2,5 mIU/L →NS CH negative (cut off=15)
 IRT = 12,8 ng/mL → NS CF negative (cut off=65)
 17OHP > 315 nmol/l (700 nmol/l) → positive (cut off 20)
 S/Na = 128 mmol/l, S/K = 5,6 mmol/l, ACTH = 872 pg/ml,
17 OHP> 300 nmol/l (in venous blood)
 dg. CAH, v.s. type SW
16
Website
For more information about newborn screening
program in the Czech Republic you can contact website:
www.novorozeneckyscreening.cz
(English version)
17
Thank you for your attention
18