Diabetes insipidus and increased serum levels of leptin and lactate-dehydrogenase (LDH) in an adolescent boy with a primary intracranial germinoma. Case Report and an endocrinological revaluation of literature

Abstract

A 16-year-old boy presented with a four-month history of polyuria-polydipsia and a diplopia which had reverted after treatment. The neuroimaging studies performed had been strongly suggestive of an optic nerve glioma, while endocrinological investigation (beta-hCG 420 IU/L) has lead to the correct diagnosis later confirmed at the immunohystochemical analysis performed at biopsy. The high serum level of hCG was unaffected by bromocriptine nor octreotide, while the PRL level (80.0 microg/L) was reduced only by bromocriptine. Among the several tumor markers which may be secreted by such lesions, ours is the first reported case of an elevation of serum LDH for a primary intracranial germinoma. Moreover, the elevated value of serum leptin reported by us might be due to the insensitivity of the hypothalamic structures to endogenous leptin.

Endocrine Findings in Patients with Optico-Hypothalamic Gliomas

“…Only 2 out of 38 patients showed more than one endocrine abnormality. Hyperprolactinemia and secondary hypogonadism were the most frequent findings, although hyperprolactinemia is not specific for pituitary dysfunction (Carella et al, 1999). Postoperative assessment of endocrine functions showed that hyperprolactinemia, secondary hypogonadism and hypothyroidism resolved in most of the adult patients (Table 2), but not in children.…”