Idiopathic hypothalamic diabetes insipidus, pituitary stalk thickening, and the occult intracranial germinoma in children and adolescents.
We report nine consecutive children and adolescents [five females and four males; aged 2 yr 8 months (m) to 18 yr 1 m] studied over the last 5 yr with idiopathic central diabetes insipidus. In addition to vasopressin deficiency, anterior pituitary hormone deficiencies were detected, either on evaluation at presentation or during follow-up studies over the following 3 yr. Four patients had an increased concentration of plasma PRL. One patient had multiple pituitary hormone deficiencies at diagnosis, and two others developed the same by 21 m of follow-up. Brain magnestic resonance imaging scans, performed at presentation, were originally interpreted as normal in four of nine patients, except for absence of the bright posterior pituitary signal; after retrospective review, two of nine were considered normal. All of the brain magnetic resonance imaging (MRI) scans showed positive findings by 14 m of follow-up. The first abnormal finding in all patients was isolated pituitary stalk thickening. Evaluation of cerebrospinal fluid (CSF) for hCG was positive in three of eight evaluated patients; the three positive CSF values were found at presentation and 3 and 9 m after presentation. All eight patients assessed were negative for CSF alpha-fetoprotein and cytology, and no patient had serum tumor markers. Transsphenoidal biopsy of the lesion in seven of nine patients showed a germinoma in six patients and inflammatory cells in one. The six patients with documented germinoma comprise 31% of the intracranial germinomas diagnosed in this age group at the University of California-San Francisco during the last 5 yr. The patient with mononuclear inflammatory cells on biopsy along with one other patient have had spontaneous resolution of their stalk thickening. So-called "idiopathic" central diabetes insipidus warrants close follow-up to determine the etiology, especially if anterior pituitary hormone deficiencies are detected. Normal brain MRI scans or scans that show isolated pituitary stalk thickening merit follow-up with serial contrast enhanced brain MRI for the early detection of an evolving occult hypothalamic-stalk lesion. CSF evaluation is recommended at presentation because elevated CSF hCG may precede MRI abnormalities.
Mootha
S L
SL
Department of Pediatrics, University of California, San Francisco 94143, USA.
Barkovich
A J
AJ
Grumbach
M M
MM
Edwards
M S
MS
Gitelman
S E
SE
Kaplan
S L
SL
Conte
F A
FA
D000293:Adolescent; D001706:Biopsy; D001932:Brain Neoplasms / Q000150:complications* / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D006063:Chorionic Gonadotropin / Q000097:blood / Q000134:cerebrospinal fluid; D003919:Diabetes Insipidus / Q000209:etiology* / Q000473:pathology; D005260:Female; D018237:Germinoma / Q000150:complications* / Q000473:pathology; D006801:Humans; D007031:Hypothalamus / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D010902:Pituitary Gland / Q000473:pathology*; D010908:Pituitary Hormones, Anterior / Q000172:deficiency; D014667:Vasopressins / Q000172:deficiency; D000509:alpha-Fetoproteins / Q000032:analysis
D006063:Chorionic Gonadotropin; D010908:Pituitary Hormones, Anterior; D000509:alpha-Fetoproteins; D014667:Vasopressins