C - Paeds Clin Chem (E)

Question 1

problems in low birth weight babies

Answer 1

RDS
IVH
patent ductus arteriosus
NEC

Question 2

what is NEC

Answer 2

inflammation of bowel wall progressing to necrosis and perforation

Question 3

XR of NEC

Answer 3

intramural air

Question 4

Sx of NEC

Answer 4

blood stool
abdo distention

Question 5

when do nephrons develop?

Answer 5

6 weeks post conception

Question 6

when does a foetus start producing urine

Answer 6

week 10 gestation

Question 7

when is functional maturity of GFR reached

Answer 7

2 years of age

Question 8

the distal tubule of a baby is relatively unresponsive to aldosterone; what effect does this have on Na?

Answer 8

persistent loss of Na

Question 9

what % of body weight is fluid in
preterm baby?
neonate (term)?
adult?

Answer 9

85%
75%
60%

Question 10

why do babies have a high insensible water loss

Answer 10

high SA
high skin blood flow
high metabolic / resp rate
high transepidermal fluid loss

Question 11

which 3 drugs when given to neonates can cause derranged Na

Answer 11

bicarb (increased Na)
ABx (increased Na)
caffeine / theophylline (renal Na loss)

Question 12

main cause of hyponatraemia in children

Answer 12

congenitla adrenal hyperplasia

Question 13

what enzyme is missing is CAH

Answer 13

21 alpha hydroxylase

Question 14

what substrate is high in CAH

Answer 14

17 OH pregnenolone (cortisol precursor)

Question 15

what does high 17 OH pregnenolone cause in CAH

Answer 15

high androgens –> ambiguos genitals

Question 16

complication of CAH

Answer 16

addisons crisis - hyponatraemia

Question 17

why do babies get hyper BR

Answer 17

RBC breakdown as HbF to HbA
low rate of transport to liver
enhanced enterohepatic circulation

Question 18

is hyper BR in babies conjugated or unconjugated

Answer 18

unconjugated

Question 19

Tx for BR

Answer 19

phototherapy
exhange transfusion

Question 20

complication of hyperBR

Answer 20

kernicterus

Question 21

is the BR chart the same for all babies?

Answer 21

no its different for pre term

Question 22

causes of hyperBR

Answer 22

haemolytic disease - ABO or rhesus
G6PD def
schistocytosis
Criger-Najjar syndrome (metabolic)

Question 23

what is prolonged jaundice

Answer 23

> 14 days in term
21 days in preterm

Question 24

causes of prolonged jaundice

Answer 24

prenatal infection / sepsis / hepatitis
hypothyroidism
breast milk jaundice

Question 25

a conjugated hyperbilirubinaemia is always _____

Answer 25

PATHOLOGICAL

Question 26

what is the threshold for conjugated hyperBR

Answer 26

> 20umol/L

Question 27

causes of conjugated hyperBR

Answer 27

biliary atresia
choledocal cyst
ascending cholangitis - TPN babies
galactosaemia
alpha 1 anti trypsin deficiency

Question 28

epidemiology of biliary atresia

Answer 28

1/17,000

Question 29

mx of biliary atresia

Answer 29

early surgery (before 6 months of age)

Question 30

how does baby get Ca and PTH

Answer 30

from mothers bones

Question 31

how does a babies Ca and PTH compare to adults

Answer 31

lower Ca
higher PTH

Question 32

low ca condition of babies

Answer 32

osteopaenia of prematurity

Question 33

biochem of osteopaenia of prematurity

Answer 33

normal Ca
phosphate <1mmol/L
ALP >1200 U/L

Question 34

Tx of osteopaenia of prematurity

Answer 34

phosphate / calcium supplements

Question 35

what is rickets

Answer 35

osteopnaeia due to deficiency of vit D

Question 36

PC of rickets

Answer 36

frontal bossing
bowlegs
knock knees
muscular hypotonia

Question 37

alternative presentation of rickets

Answer 37

tetany
hypocalaemic seizures
cardiomyopathy