Somatostatin infusion withdrawal in the diagnosis of childhood growth hormone deficiency.
OBJECTIVE
An evaluation of growth hormone (GH) testing for GH deficiency (GHD) in childhood is confounded by the lack of a world-wide consensus on the definition of GHD. Although a single GH test remains the most powerful biochemical tool in the evaluation of a child with growth failure, the test remains far from ideal. Withdrawal of somatostatin (SS) infusion is followed by a rebound rise of GH thought to be mediated by endogenous GH-releasing hormone (GHRH) function. This study was designed to compare the GH response to 90 min SS infusion in children with normal GH secretion versus children with GH deficiency.


METHODS
Ten children with GHD and 10 healthy controls (NC) have been evaluated for GH response to somatostatin infusion withdrawal (SSIW) and compared with response of two provocative tests, glucagon plus propranolol test and L-Dopa test. All children received constant infusion of somatostatin for 90 min (3 microg/kg per h, Stilamin, Serono, Aubonne, Switzerland). In order to determine GH, blood samples were obtained 90 min before the SS infusion and 0, 15, 30, 45, 60, 75, and 90 min after the cessation of infusion.


RESULTS
Growth hormone peak levels with SSIW were significantly lower in GH deficient children than in healthy children (2.5 +/- 1.2 ng/dL, vs 21.9 +/- 5.3 ng/dL, respectively, P < 0.01). No adverse effects were observed during or after somatostatin infusion.


CONCLUSIONS
In the present study, SSIW elicited a significant GH rise in healthy children but not in children with GH deficiency. Although further controlled studies using more data are necessary to expand these findings, the results suggested that children with GH deficiency can be reliably discriminated from healthy children by SSIW.
Bosnak
Mehmet
M
Department of Pediatrics, Dicle University, Medical School, Diyarbakir, Turkey. mbosnak@dicle.edu.tr
Dikici
Bunyamin
B
Haspolat
Kenan
K
Dogru
Omer
O
Ozkan
Ilker
I
Ece
Aydin
A
D016022:Case-Control Studies; D002648:Child; D005260:Female; D019382:Human Growth Hormone / Q000008:administration & dosage* / Q000097:blood / Q000172:deficiency*; D006801:Humans; D007260:Infusion Pumps; D008297:Male; D013997:Time Factors
D019382:Human Growth Hormone