Endocrine Abstracts

Introduction: Pituitary hyperplasia (PH) is relatively a rare condition in children. As in adults, it can be secondary to a long-standing primary hypothyroidism and can sometimes be mistaken with a pituitary macro-adenoma as in the following observation:

Case report: Herein, authors describe a girl aged 10 years old sent by her neurosurgeon for pre operative hormonal exploration of a pituitary macro adenoma measuring 13 mm in height. This one was discovered by cerebral MRI when she consulted for an abnormal gait.

After questioning the parents, we learnt she always had difficulty to learn. She had her period 6 months ago, and she is taking levothyroxine 75 μg for 3 months.

Clinical examination revealed a discreet growth retardation (−1.5 SD/TS). The rest of clinical examination did not find anything abnormal except a particular shape of her eyes that look like Mongols’. The karyotype confirmed our impression as it showed a mosaic form (15%). Thyroid assessment showed increased TSH (8 IU/ml). Thyroid ultrasound demonstrated an hypo-echoic gland. Thyroperoxydase antibodies were increased arguing for an autoimmune origin which is common in patients with Down syndrome. Under 100 μg levothyroxine TSH and MRI were normalized.

Conclusion: The association of primary thyroid deficit with a pituitary lesion argued for a secondary thyrotrophic pituitary adenoma which is relatively rare in children. But, this diagnosis was confirmed in retrospect by MRI that showed a normalization of pituitary size under 100 μg levothyroxine. Pituitary hyperplasia due to puberty or hypothyroidism should be known by neurosurgeons who are not used to this conditions.