Growth Hormone Releasing Hormone

This test was developed and its performance characteristics have been determined by Quest Diagnostics Nichols Institute. It has not been cleared or approved by the U.S. Food and Drug Administration. The FDA has determined that such clearance or approval is not necessary. Performance characteristics refer to the analytical performance of the test.

37557X

4 mL plasma (1.1 mL minimum).

Use special collection tube labelled PTH-RP and Releasing Factors available from Quest Diagnostics Nichols Institute.
Place PTH-rP cocktail tubes on ice prior to drawing samples. Collect the whole blood into a syringe and transfer the sample into the cocktail tube. Alternatively, if a syringe is not available, collect the blood in a plain red-top tube and immediately transfer the sample into the cold cocktail tube. Mix thoroughly by inversion. Immediately separate the plasma from the cells in a refrigerated centrifuge and transfer to a plastic test tube. Freeze immediately at -20 degrees or colder. If a refrigerated centrifuge is not available, chill the tubes and centrifuge tube holders for 5 minutes in an ice slurry. Ship frozen.

PTH-Related Protein and Releasing Factors tube

Frozen

Received room temperature or refrigerated
Do not collect in a PTH-related protein (green-top) plastic tube.

In more than 99% of patients with acromegaly there is hypersecretion of Growth Hormone. The remaining cases result from GHRH hypersecretion by peripheral tumors or rarely, neuroendocrine tumors.