Thyroid imaging
ESPE consensus statement (1) on congenital hypothyroidism recommends thyroid imaging for all babies with suspected congenital hypothyroidism because:
- It is more informative than blood tests alone.
- It will aid in guiding options for genetic counselling.
- With the results, it is possible to determine the likelihood of lifelong treatment if permanent congenital hypothyroidism is proven.
- It provides a useful additional guide as to thyroxine dose (agenesis is likely to require larger doses).
Isotope scans should be performed by day 5 of the start treatment (5) to ensure the avoidance of false negatives, due to TSH suppression (it is advisable to check thyroid function on the day of scans to confirm the reliability of results).
Currently, if imaging is to be performed, the Royal Hospital for Children, Glasgow is currently the only site that is able to perform these scans. If scanning is to be considered, there should be early discussion with a paediatric endocrinologist.
- Imaging should never be allowed to delay the initiation of treatment.