Clinical Features, Co-morbidities and Diagnosis of Acromegaly.

Growth hormone (GH), an anabolic hormone, is synthesized and secreted by the somatotroph cells located in the anterior lobe of the pituitary gland. The presence of benign tumors or adenomas in somatotroph cells may lead to a variety of endocrine symptoms and aberrant secretion of GH. Hypersecretion of GH in response to an adenoma results in acromegaly or gigantism, a condition observed in adults and associated with significant morbidity and mortality. The estimated prevalence of acromegaly in the US is approximately 15,000 people, with men and women being equally affected.

Onset of symptoms of acromegaly is insidious and generally occurs between the ages of 40 and 60. Telltale physical signs include enlarged hands, feet, nose, and lips, as well as increased sweating, fatigue, and joint pain. Biochemically, acromegaly is associated with excessively high levels of circulating GH and insulin-like growth factor I (IGF-I). As a result, patients affected by acromegaly also face an increased risk of developing type 2 diabetes, even when they do not have a predisposing family history, a typically diabetic phenotype, or other risk factors.

All patients thought to have GH-related disorders, should have their GH levels and IGF-I plasma levels checked. Though GH deficiency is well characterized, other GH-related disorders may be difficult to diagnose without a sound understanding of the underlying endocrinologic pathology. Affected patients who are not diagnosed or properly treated are at risk for increased morbidity and mortality, decreased quality of life, and potential related psychosocial challenges.

In this conversation, two endocrinologists, Dr. David M. Cook and Dr. Lawrence Katznelson, join Dr. Carlos Hamilton, Jr. to discuss the clinical features, comorbidities and diagnosis of acromegaly.

Related References/Reading:

  1. Ayuk J, Sheppard MC. Growth hormone and its disorders. Postgrad Med J. 2006;82(963):24-30.
  2. Cook DM, Ezzat S, Katznelson L, et al. American Association of Clinical Endocrinologists Medical Guidelines for Clinical Practice for the Diagnosis and Treatment of Acromegaly. Endocrine Practice. 2004;10: 213-225.
  3. Giustina A, Burkan A, Casanueva FF, et al. Criteria for cure of acromegaly: a consensus statement. J Endocrinol Metab. 2000;85:526-29.
  4. Katznelson L. Current thinking on the management of the acromegalic patient. Curr Opin Endocrinol Diabetes Obes. 2007;14(4):311-6.
  5. Katznelson L. Diagnosis and treatment of acromegaly. Growth Horm IGF Res. 2005;15 Suppl A:S31-5.
  6. Melmed, S. Medical Process: Acromegaly. N Engl J Med. 2006;355:2558-2573.
  7. Tiu SC, Ng CM, Shek, Chi CS et al. Multiple morbidities in acromegaly with apparently normal growth hormone levels. Endocrinologist. 2007;17:175-178.
  8. Tzanela M. Dynamic tests and basal values for defining active acromegaly. Neuroendocrinology. 2006;83(3-4):200-4.