Background: Hypothalamic hamartomas (HH) are rare non-progressive brain tumor malformations that occur early during brain development. Most of the cases are sporadic and nonsyndromic. Variation in size and location of the hamartoma within the hypothalamic region is not always associated with the severity of the clinical presentation. A wide range of symptoms could occur - from nonsymptomatic to severely affected cases that include seizures (mostly gelastic), behavioral difficulties and endocrinological disturbances. Among all, precocious puberty is most common endocrinological dysfunction; others present less frequently.
Objective and hypotheses: Evaluation of GH in a child with hypothalamic hamartoma.
Method: A girl approached our clinic due to the short stature. The child was born on term BW3350gr/BL50 cm. During early infancy growth was within the normal curve. Growth velocity started to decline after the age of 4 years. At the age of 7 years the child was 4SDS below the mean for height and 3SDS for weight. Pubertal development started at 8.5 years of age.
Results: GH deficiency was confirmed with stimulation tests (peak value of 4.3 ng/ml) and low IGF1. MRI of the pituitary showed large hypothalamic hamartoma without tendency for growth during the two following years, whereas the pituitary gland was normal. The girl showed behavioral problems -shyness, timidity and inability to accustom to school activities. Also she had frequent headaches and episodes of crying. Neurological examination as well as ortooptic testing was normal. Other pituitary hormones were normal as well.
Conclusion: Clinical presentation of HH is mostly associated with a particular position of the hamartoma. Since the size of HH in our case is 30 mm, both possible mechanisms could be involved impaired GHRH secretion from the lower parts of the hypothalamus (arcuate nucleus) and inadequate control of somatostatin levels produced from upper parts of the hypothalamus (rostral periventricular nucleus). However, short stature should be considered as a rare feature of HH.
10 - 12 Sep 2016
European Society for Paediatric Endocrinology