Key-Role of TSH Deficiency in Disclosing Craniopharyngioma Diagnosis in a Short Girl with Hashimoto’s Thyroiditis

Background: Hashimoto’s thyroiditis (HT) in childhood
may present with either euthyroidism (52.1% of cases), or primary
overt hypothyroidism (22.2%), subclinical hypothyroidism
(19.2%), overt hyperthyroidism (3.5%), or subclinical hyperthyroidism
(3%). In a large series of 608 children and adolescents with
presenting HT, we found in no cases a biochemical picture with
low free thyroxine (FT4) and normal or low-normal TSH serum
levels, i.e. a thyroid pattern that is consistent with central
hypothyroidism (CH), but is not compatible with HT. Therefore,
the finding of such a biochemical pattern in a child with HTshould
direct work-up towards seeking an associated central cause of
hypothyroidism. Aim: The aim of the present case report is to
reinforce the above view. Case report: In a short girl with celiac
disease and HT, the suspect of an associated pituitary lesion was
suggested, despite the lack of neuro-ophthalmic symptoms, by
the finding of a thyroid function pattern that was not compatible
with HT (low FT4 with normal TSH). This case report reinforces
the view that the finding of a normal TSH in presence of a low FT4
should always alert pediatricians and raise the suspect of central
hypothyroidism, even when a primary thyroid disease has been
already identified. In this case TSH deficiency played a critical role
in disclosing diagnosis of craniopharyngioma (CP). Conclusions:
Among the endocrinological manifestations of CP, TSH deficiency
is observed in only 25% of children, whereas GH deficiency (100%
of cases) and ACTH deficiency (68%) are distinctly more frequent.
In this case report TSH deficiency was present and played a critical
role in disclosing diagnosis of CP. If it had been absent, it might
be hypothesized that diagnosis of CP would have been furtherly
delayed.