Tests and diagnosisBy Mayo Clinic staff
To begin the diagnostic process, your doctor will take a medical history and conduct a physical exam. Then he or she may recommend the following steps:
- GH and IGF-I measurement. After you've fasted overnight, your doctor will take a blood sample to measure your levels of GH and IGF-I. Elevated levels of these hormones suggest acromegaly.
- Growth hormone suppression test. This is the definitive method for verifying acromegaly. In this test, your blood levels of GH are measured before and after you drink a preparation of sugar (glucose). Normally, glucose ingestion depresses levels of GH. If you have acromegaly, your GH level will tend to stay high.
- Imaging. Your doctor may recommend that you undergo an imaging procedure, such as magnetic resonance imaging (MRI), to help pinpoint the location and size of a tumor of your pituitary gland. If radiologists, who usually perform the procedures, see no tumor of your pituitary, they may look for nonpituitary tumors that might be responsible for high levels of GH.
- Acromegaly. National Institute of Diabetes and Digestive and Kidney Diseases. http://www.endocrine.niddk.nih.gov/pubs/acro/acro.htm. Accessed Oct. 31, 2012.
- Longo DL, et al. Harrison's Online. 18th ed. New York, N.Y.: The McGraw-Hill Companies; 2012. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=4. Accessed Nov. 2, 2012.
- McPhee SJ, et al. Current Medical Diagnosis & Treatment 2012. 51st ed. New York, N.Y.: The McGraw-Hill Companies; 2012. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=1. Accessed Nov. 2, 2012.
- Minniti G, et al. Radiation techniques for acromegaly. Radiation Oncology. 2011;6:167.
- Giustina A, et al. A consensus on criteria for cure of acromegaly. The Journal of Clinical Endocrinology &Metabolism. 2010;95:3141.
- Ben-Shlomo A, et al. Clinical, quality of life, and economic value of acromegaly disease control. Pituitary. 2011;14:284.
- Parlodel (prescribing information). East Hanover, NJ: Novartis Pharmaceuticals Corporation; 2012. http://www.pharma.us.novartis.com/product/pi/pdf/parlodel.pdf. Accessed Nov. 13, 2012.
- Cycloset (prescribing information). San Diego, Calif.: VeroScience, LLC; 2010. http://www.veroscience.com/CyclosetFDAapprovedPackageInsert.htm. Accessed Nov. 13, 2012.
- Cabergoline (prescribing information). Sellersville, Pa.: Teva Pharmaceuticals; 2012. http://www.tevagenerics.com/default.aspx?pageid=3364&sortby=ProductName&ProductName=Cabergoline+Tablets&BrandName=Dostinex%C2%AE+Tablets. Accessed Nov. 13, 2012.
- Martinkova J, et al. Impulse control disorders associated with dopaminergic medication in patients with pituitary adenomas. Clinical Neuropharmacology. 2011;34:179.