The challenge of pituitary hyperplasia differential diagnosis in a young girl with growth arrest

Resumen

Growth arrest is an alarming condition which requires precise and tempestive investigations in order to provide accurate diagnosis. Long-standing primary hypothyroidism (PHT) may rarely occur as a growth arrest as the only clinical sign at onset in children. The most common cause of PHT in children and adolescents is represented by Hashimoto’s thyroiditis (HT), an autoimmune disease which frequently presents clinically with goitre. Rarely, HT may present as an atrophic variant without goitre, which may delay the diagnosis of PHT. Long-standing PHT is an unusual cause of pituitary hyperplasia (PH) and it has to be differentiated from severe conditions, including neoplasms. Loss of thyroxine feedback determines overproduction of thyrotropin releasing hormone, thyrotropin (TSH)-releasing cells hyperplasia and a consequent pituitary enlargement. Levothyroxine replacement therapy usually determines regression of PH. This report describes a case of an 11-year-old girl suffering from PHT and secondary PH due to autoimmune atrophic thyroiditis whose only onset symptom was growth arrest.
Thyroid hormone evaluation should be included in the first step of evaluations in patients with growth arrest even in the absence of clear clinical signs suggestive of thyroid disfunction. In patients with pituitary enlargement, thyroid function tests are important to recognize PH secondary to PHT and to avoid unnecessary surgery.