تسجيل الدخول

تسجيل

Excessive GH in Adults: Acromegaly

المؤلف:  Norman, A. W., & Henry, H. L.

المصدر:  Hormones

الجزء والصفحة:  3rd edition , p78-79

2026-06-29

105

 Excessive GH secretion in adults leads to a constellation of symptoms known as acromegaly and most commonly results from one of several types of GH-secreting pituitary tumors. Hypothalamic tumors that oversecrete GHRH may also be responsible. Acromegaly is quite rare and its incidence is not well established. It generally has a slow progression and can be present for a decade or more before being accurately diagnosed. Since the acromegaly is of adult onset and the epiphyseal growth plates of the long bones close at the end of puberty, the hypersecretion of GH results in excessive growth of only those tissues still capable of responding to it. These include the mandible, bringing about changes of facial structure and the hands and feet, which become enlarged. These changes in appearance are often so gradual that they are not the patient’s initial complaint upon presentation. Rather, the headache resulting from the growing tumor is the most common symptom that brings the patient to the clinic. Soft-tissue overgrowth causes a number of symptoms including neuropathy; cardiomyopathy and cardiovascular disease; debilitating arthritis; sleep apnea due to airway obstruction; respiratory disease and, because of the role of GH in carbohydrate metabolism, carbohydrate intolerance. Untreated acromegaly leads to a 2- to 4-fold increase in mortality compared to age-matched controls.

The primary goal of treatment of acromegaly is to reduce excessive GH levels. Surgery is one method to achieve this but is accompanied by serious risks, one of which is the difficulty in removing all of the tumor without damaging nearby structures. Radiation of the tumor has also been used, but the response in terms of lower GH levels is much slower than with surgery. Pharmaceutical therapies include GH receptor antagonists and somatostatin receptor ligands that block GH secretion by the tumor cells and reduce tumor size.