TY - JOUR
T1 - Thyroid scintigraphy and perchlorate test after recombinant human TSH
T2 - A new tool for the differential diagnosis of congenital hypothyroidism during infancy
AU - Fugazzola, Laura
AU - Persani, Luca
AU - Vannucchi, Guia
AU - Carletto, Marco
AU - Mannavola, Deborah
AU - Vigone, Maria Cristina
AU - Cortinovis, Francesca
AU - Beccaria, Luciano
AU - Longari, Virgilio
AU - Weber, Giovanna
AU - Beck-Peccoz, Paolo
PY - 2007/9
Y1 - 2007/9
N2 - Purpose: Prompt initiation of l-thyroxine therapy in neonates with congenital hypothyroidism (CH) often prevents the performance of functional studies. Aetiological diagnosis is thus postponed until after infancy, when the required investigations are performed after l-thyroxine withdrawal. The aim of this study was to verify the efficacy and safety of new protocols for rhTSH (Thyrogen) testing during l-thyroxine replacement in the differential diagnosis of CH. Methods: Ten CH patients (15-144 months old) were studied. Seven had neonatal evidence of gland in situ at the ultrasound examination performed at enrolment and received two rhTSH injections (4 μg/kg daily, i.m.) with 123I scintigraphy and perchlorate test on day 3. Three patients with an ultrasound diagnosis of thyroid dysgenesis received three rhTSH injections with 123I scintigraphy on days 3 and 4. TSH and thyroglobulin (Tg) determinations were performed on days 1, 3 and 4, and neck ultrasound on day 1. Results: rhTSH stimulation caused Tg levels to increase in eight cases. Blunted Tg responses were seen in two patients with ectopia and hypoplasia. Interestingly, in two cases the association of different developmental defects was demonstrated. Perchlorate test revealed a total iodide organification defect in two patients, including one with a neonatal diagnosis of Pendred's syndrome, who were subsequently found to harbour TPO mutations. rhTSH did not cause notable side-effects. Conclusion: These new rhTSH protocols always resulted in accurate disease characterisation, allowing specific management and targeted genetic analyses. Thus, rhTSH represents a valid and safe alternative to l-thyroxine withdrawal in the differential diagnosis of CH in paediatric patients.
AB - Purpose: Prompt initiation of l-thyroxine therapy in neonates with congenital hypothyroidism (CH) often prevents the performance of functional studies. Aetiological diagnosis is thus postponed until after infancy, when the required investigations are performed after l-thyroxine withdrawal. The aim of this study was to verify the efficacy and safety of new protocols for rhTSH (Thyrogen) testing during l-thyroxine replacement in the differential diagnosis of CH. Methods: Ten CH patients (15-144 months old) were studied. Seven had neonatal evidence of gland in situ at the ultrasound examination performed at enrolment and received two rhTSH injections (4 μg/kg daily, i.m.) with 123I scintigraphy and perchlorate test on day 3. Three patients with an ultrasound diagnosis of thyroid dysgenesis received three rhTSH injections with 123I scintigraphy on days 3 and 4. TSH and thyroglobulin (Tg) determinations were performed on days 1, 3 and 4, and neck ultrasound on day 1. Results: rhTSH stimulation caused Tg levels to increase in eight cases. Blunted Tg responses were seen in two patients with ectopia and hypoplasia. Interestingly, in two cases the association of different developmental defects was demonstrated. Perchlorate test revealed a total iodide organification defect in two patients, including one with a neonatal diagnosis of Pendred's syndrome, who were subsequently found to harbour TPO mutations. rhTSH did not cause notable side-effects. Conclusion: These new rhTSH protocols always resulted in accurate disease characterisation, allowing specific management and targeted genetic analyses. Thus, rhTSH represents a valid and safe alternative to l-thyroxine withdrawal in the differential diagnosis of CH in paediatric patients.
KW - Congenital hypothyroidism
KW - Perchlorate test
KW - Recombinant human TSH
KW - Thyroid scintigraphy
KW - Total iodide organification defect
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U2 - 10.1007/s00259-007-0377-6
DO - 10.1007/s00259-007-0377-6
M3 - Article
C2 - 17318546
AN - SCOPUS:34548185445
VL - 34
SP - 1498
EP - 1503
JO - European Journal of Pediatrics
JF - European Journal of Pediatrics
SN - 0340-6199
IS - 9
ER -