IEM & general information of healthy infants

Question 1

def. inborn error and IEM

Answer 1

 Definition: inborn error
o Gene mutations, usually caused by recessive gene
o Dysregulation in the synthesize of enzymes, coenzymes and transporters necessary for the metabolism of carb, lipids and amino acids

 Definition: metabolism
o Accumulation of toxic metabolites
o Deficiency in essential metabolites

Question 2

T/F IBE can be detected at early age

Answer 2

F

IEM may start to present at any age with wide range of severity but mostly manifest around the newborn period

Question 3

why do newborn error screening?

Answer 3

there was high incidence of metal retardation before screening; to catch the problem before the damage becomes accumulated

Question 4

list down 5/8 common syntoms

Answer 4

1. overwhelming illness in the new born period
2. cardiomyopathy
3. seizure
4. recurrent vomiting
5. developmental delay/mental retardation
6. neuropsychiatric symptoms
7. poor growth/failure to thrive
8. loss of previously acquired skills

Question 5

newborn error screening: test

Answer 5

 First test: urinary phenyl pyruvic acid for PKU
 Dry blood spots: collect 24-48 hours after birth for metabolic intermediaries detection
• Canada: 38 conditions

Question 6

6 guidelines for IE

Answer 6

1. In differential diagnosis of sepsis, anoxic encephalopathy or toxic ingestion
2. Persist symptoms
3. Typical common laboratory test fail to determine a definitive diagnosis
4. Can present as either acute illness or as chronic disease/ recurrent and progressive/ at any age
5. Can occur in the context of negative family Hx or genetic/metabolic disorder (recessive gene mutation)
6. Neonatal death from undetermined causes

Question 7

list down the first 3 most common IEM conditions

Answer 7

PKU: phenyl ketonuria
MMA: Methylmalonic acidemia
galactosemia

Question 8

what is the different between Mitochondrial disorder and other common IEMs?

Answer 8

it is from X chromosome only: x-linked mtDNA mutations.

Most IEMs are autosomally recessive

Question 9

Most commonly absent enzyme: PKU

Answer 9

PAH: phenylalanine hydroxylase

Question 10

Most commonly absent enzyme: MMA

Answer 10

Methyl malonyl

Question 11

4 Modals for nutrition management

Answer 11

A: restrict substrate
B:supplement product
C:supplement co-factor to increase residual enzyme activity
D: ajunct therapies—remove abnormal metabolites

Question 12

what are the 4 difficulties in terms of nutrition management?

Answer 12

1. single or multiple nutrition restriction
2. risk of nutrition deficiency
3. specific supplements, especially regarding essential AAs
4. Appropriate growth = the achievement of metabolic balance, which is hard

Question 13

what is the priority in nutrition management? how to monitor?

Answer 13

• NRG adequacy

- proteie-energy ratio

Question 14

if someone has IE of protein metabolism, how would you increase total NRG?

Answer 14

choose low-protein breads and pasta for NRG adequacy without adding more protein to the foods

Question 15

AAs mix vs the source of whole protein

Answer 15

prefer to whole protein (more efficient in some disorder)

Question 16

why protein balance is very important?

Answer 16

• Growth will be limited by the AA in shortest or inadequate nitrogen supply in the diet.

Question 17

dietary fat is a good source to meet NRG requirement except:

Answer 17

IE regarding fat oxidation

Question 18

Four 4 steps in terms of overall PKU management

Answer 18

1. Reduce blood phe under 360 umol/L
2. Add little by little intact protein to cover phe needs
3. Supplement with large neutral AA to compete for he transporter
4. Inadequate protein = Assess deficiency?

Question 19

How to reduce blood phe under 360 umol/L

Answer 19

Fully restrict all protein sources that contain Phe until below 360 umol/L

Question 20

Acute management of PKU for infants

Answer 20

• Reduce blood phe < 360 umol/L
• Phe-free formulas
• Can reintroduce standard formula or breastmilk in controlled amounts (the level of phe vary)

Question 21

chronic management of PKU for infants

Answer 21

• Manintain blood phe at range 120-360 umol/L
• Supporting normal growth and development
• Preventing nutrient deficiencies

Question 22

what is the main end goal of nutrition therapy for IEM

Answer 22

nutrition adequacy for growth (follow the growth curve)

Question 23

what is Galactosemia

Answer 23

: high accumulation of galactose-1-P, galactose, galactitol and galactonate due to deficiency of GALT. Sometimes, other enzyme deficiencies may exist as well, like GALK and GALE.

Question 24

the most common complication

Answer 24

jaundice because of liver damage

Question 25

list 4/6 common consequence of galactosemia

Answer 25

o	Most common complication--- jaundice because of liver damage
o	Anorexia
o	Potential risk of sepsis
o	Ultimately fatal 
o	Enlarged liver 
o	Kidney damage

Question 26

overall nutrition management of galactosemia

Answer 26

restriction of galactose through drinking metabolized milk.

Question 27

the concern if no restriction of galactose intake

Answer 27

Usual unmetabolized milk will cause the galactose accumulation and ultimately damage the liver, eyes, kidney and brain

Question 28

Acute management: galactosemia

Answer 28

• Soy-based medical food (forbid dairy components)
• PN can be an option after EN or PO
• Medication: avoid the one containing lactose fillers

Question 29

Chronic management: galactosemia

Answer 29

• Dairy elimination
• NO Breast feeding
• Rec to continue monitor Vit-D status for bone health
• Education to parents: label reading
• F/V is okay (negligible amounts of Gal)

Question 30

list 4 items that contain galactose/lactose but ppl commonly don’t realize

Answer 30

butter, organ meats, fermented soy products and soy sauce, meat by-products, milk chocolate

Question 31

• Breast-fed babies usually feed ? times or more per day

Answer 31

averagely 8 or more

for commercial formula: 6 or more

Question 32

how do you know it is feeding enough

Answer 32

Urine, Stools, Weight

Baby seems full after drinking

Question 33

list 5 signs that the baby is not drinking enough

Answer 33

• baby is very drowsy and difficult to wake for feeding
• urine is dark yellow or very little (e.g., more than 6 hours between wet diaper)
• there are orange stains in the urine after the first two days
• stools still contain meconium after the 5th day
• fewer than one bowel movment per 24 hours between the age of 5 days to 4 weeks

Question 34

when to report APGAR score

Answer 34

• Reported at least at 1 minute and 5 minutes after birth in all infants

Question 35

APGAR: the range of normal

Answer 35

7-10

Question 36

what is 0 APGAR score for R?

Answer 36

no crying

Question 37

heart rate: 2 APGAR SCORE

Answer 37

HR > 100/min