Congenital Hypothyroidism

Congenital Hypothyroidism treatment:

 

All newborns should be screened:
     Cord blood/ venous sample D3-D5

TSH (mU/L)

<20
No further testing
>80
Immediate TSH & fT4 venous sample
Immediate Rx don't wait for report
40-80
Immediate TSH & fT4 venous sample
Start Rx after report
20-40
TSH & fT4 venous sample after 7-10days
Rx if TSH >20 in <2wk age
                 >10 in > 2wk age

T4 & TSH for starting Rx:
 
T4
fT4
TSH
<8µg/dl
<100nmol/L
<1.1ng/dl
<12pmol/L
Any
<10µg/dl
<128nmol/L
<1.17ng/dl
<15pmol/L
>20mU/L in <2wk age
>10mU/L in >2wk age
N
N
>10mU/L in >3wk age
 
Rx dose:
L-thyroixine: 10-15 µg/kg/day

Monitoring schedule:
 
Age
Monitoring
0-6m
1wk after start of Rx
every 2wks till TSH normal
every 2 months till 6m age
6m-3yr
every 3months
>3yrs
every 3-16months
4-6wks after any change in dose/brand
After 3yrs of Rx
Stop for 1 month
Then TSH, T4
Target: maintain T4/fT4 in upper half of normal value
T4:  10-16µg/dl
fT4: 1.4-2.3ng/dl
(Sampling-atleast 4hrs after thyroxine intake)