Abstract
To study a potential alteration of hypothalamic centers involved in the negative feedback
action of leptin on body weight, serum leptin levels were measured in relation to
BMI in 18 patients following surgery for a hypothalamic craniopharyngioma (Ctx), and
were compared to levels found in 21 patients operated for a pituitary adenoma (Ptx)
or in healthy control subjects. All subjects with Ptx received rhGH replacement therapy
(0.5 to 2 IU/m2/d), and serum leptin levels were followed in 3 months intervals over 24 months. Serum
leptin levels in patients with Ptx were comparable to controls, whereas 7 of the 18
patients with Ctx had higher than expected concentrations for their BMI. GH treatment
in Ptx subjects did not alter serum leptin levels. In 5 Ctx patients where preoperative
samples were available, weight gain in parallel to an increase in serum leptin levels
was observed but only minimal changes in 4 others. Our data support the role of leptin
as an important marker of body weight. The rapid increase in serum leptin levels observed
in some Ctx subjects suggests that early postoperative measurement of serum leptin
levels may help to identify patients at risk of weight gain following hypothalamic
destruction.
Key words
ob Gene - Craniopharyngioma - Pituitary Adenoma - rhGH - Obesity
