[Langerhans cell histiocytosis associated with pituitary stalk transection]

Clinical manifestations of hypothalamic-pituitary Langerhans'cell histiocytosis are commonly, diabetes insipidus and sometimes growth hormone deficiency. Their morphologic characteristics on magnetic resonance imaging are absence of posterior pituitary hyperintensity and thickening of the pituitary stalk. Pituitary stalk transection is characterized on magnetic resonance imaging by the absence of pituitary stalk visibility, hypoplasia of the anterior hypophysis and ectopic posterior pituitary hyperintense signal. This syndrome has been shown to be associated with either isolated growth hormone deficiency or multiple anterior pituitary hormone deficiency, but normal posterior pituitary function.

We report our experience with a six-year-old boy who had been treated for three years for a multisystem Langerhans'cell histiocytosis with diabetes insipidus and who was admitted because of short stature. Endocrinological examinations demonstrated a profound growth hormone deficiency and a partial central hypocorticism. Magnetic resonance imaging showed pituitary stalk transection and a midline anomaly of the brain (Arnold Chiari type I malformation).

Although, some events of his perinatal history lead to the hypothesis of a malformative origin, the progression of Langerhans' cell histiocytosis affected tissues to fibrosis, suggest that this disease is the cause of the patient's hypothalamohypophyseal lesions.