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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
5
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pubmed:dateCreated |
1998-6-4
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pubmed:abstractText |
There is now wide consensus that, within an appropriate clinical context, GH deficiency (GHD) in adults must be shown biochemically by provocative testing of GH secretion and that appropriate cut-off limits have to be defined for each provocative test. Insulin-induced hypoglycemia (ITT) is indicated as the test of choice, and severe GHD, to be treated with recombinant human GH replacement, is defined by a GH peak response to ITT of less than 3 micrograms/L. GHRH + arginine (GHRH + ARG) is one of the most promising tests in alternative to ITT. In fact, it has been reported as a potent, reproducible, and age-independent test and that it is able to distinguish between GHD and normal adults. The aim of the present study was to compare the GH response to ITT and GHRH + ARG in a large group of hypopituitary adults (n = 40; 29 male and 11 female; age: 36.4 +/- 2.1 yr). The third centile limit of the peak GH response to ITT has been reported as 5 micrograms/L, whereas in our lab, that to GHRH + ARG is 16.5 micrograms/L. In hypopituitary adults, the mean peak GH response to ITT (1.5 +/- 0.2 micrograms/L, range: 0.1-8.5 micrograms/L) was lower (P < 0.001) than that to GHRH + ARG (3.0 +/- 0.4 micrograms/L, range 0.1-12.0 micrograms/L), though there was positive correlation (r = 0.61, P < 0.001) between the GH responses to the 2 tests. The peak GH response to GHRH + ARG, but not that to ITT, was positively (though weakly) associated with insulin-like growth factor-I levels (r = 0.35, P < 0.03). Childhood and adult onset GHD patients, as well as patients with single and multiple pituitary insufficiencies, had similar peak GH responses to ITT or GHRH + ARG. Analyzing individual GH responses, 4/40 (10%) of the hypopituitary patients had GH peaks higher than 5 micrograms/L after ITT; moreover, 3 other patients (7%) had GH peaks, after ITT, higher than 3 micrograms/L. On the other hand, after GHRH + ARG, all patients had GH peaks lower than 16.5 micrograms/L, whereas 21/40 (52.5%) had GH peaks higher than 3 micrograms/L. Because 3 micrograms/L is the arbitrary cut-off for ITT, the third centile limit of which is 5 micrograms/L, we arbitrarily considered 9 micrograms/L as the cut-off point for GHRH + ARG. It is noteworthy that 37/40 (92.5%) patients had a GH peak, after GHRH + ARG, below this limit. In conclusion, our present results confirm that the ITT test is a reliable provocative test for the diagnosis of adult GHD, whereas they show that the GHRH + ARG test is, at least, as sensitive as the ITT test (provided that appropriate cut-off limits are considered). Note that even the arbitrary cut-off point below which severe GHD is demonstrated has to be appropriate to the potency of the test.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
AIM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Arginine,
http://linkedlifedata.com/resource/pubmed/chemical/Growth Hormone-Releasing Hormone,
http://linkedlifedata.com/resource/pubmed/chemical/Human Growth Hormone,
http://linkedlifedata.com/resource/pubmed/chemical/Insulin,
http://linkedlifedata.com/resource/pubmed/chemical/Insulin-Like Growth Factor I
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pubmed:status |
MEDLINE
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pubmed:month |
May
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pubmed:issn |
0021-972X
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
83
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
1615-8
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pubmed:dateRevised |
2011-11-17
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pubmed:meshHeading |
pubmed-meshheading:9589665-Adult,
pubmed-meshheading:9589665-Arginine,
pubmed-meshheading:9589665-Female,
pubmed-meshheading:9589665-Growth Hormone-Releasing Hormone,
pubmed-meshheading:9589665-Human Growth Hormone,
pubmed-meshheading:9589665-Humans,
pubmed-meshheading:9589665-Hypoglycemia,
pubmed-meshheading:9589665-Hypopituitarism,
pubmed-meshheading:9589665-Insulin,
pubmed-meshheading:9589665-Insulin-Like Growth Factor I,
pubmed-meshheading:9589665-Male
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pubmed:year |
1998
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pubmed:articleTitle |
Comparison between insulin-induced hypoglycemia and growth hormone (GH)-releasing hormone + arginine as provocative tests for the diagnosis of GH deficiency in adults.
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pubmed:affiliation |
Department of Internal Medicine, University of Turin, Italy.
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pubmed:publicationType |
Journal Article,
Comparative Study,
Research Support, Non-U.S. Gov't
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