Acromegalia

Abstract

Acromegaly is a chronic, multisystemic disease caused by chronic growth hormone (GH) hypersecretion. Over 95% of acromegaly is caused by a adenoma in the pituitary, with only rare cases of ectopic neoplasms producing growth hormone or growth hormone releasing hormone (GHRH). The condition is rare, with prevalence rates reported at 53-69 cases per million, and incidence of three to four new cases per million per year. Mortality rates are approximately two times higher than in general population, relating to an average reduction in life expectancy of around ten years. The excess deaths are due predominantly to cardiovascular, cerebrovascular and respiratory diseases. The gradual onset and non-specific nature of many of the clinical signs and symptoms of acromegaly, the delay to diagnosis averages eight to ten years from the onset of symptoms. This delay in diagnosis is reflected in the size of the pituitary tumors that are a macroadenoma (>1 cm) at the time of diagnosis in at least 70% of patients. The diagnosis is performed with high rised quantify according to age and gender of insulin like growth factor (IGF-1) and corroborates with nadir growth hormone serum levels should be above 1 ng/mL, in the two hours after 75g oral glucose. Surgery currently is the preferred approach for treating most patients. Serum growth hormone levels are controlled within an hour after complete removal of the growth hormone-secreting adenoma. Transsphenoidal microsurgical adenomectomy approach is used most commonly and, in the hands of seasoned neurosurgeons, cures most patients who are harboring a well-circumscribed microadenoma. The follow-up is continuous with determination of insulin like growth factor (IGF-1), levels of suppressed growth hormone and magnetic resonance imaging of the hypophysis.