Acromegaly
Acromegaly is acral and soft-tissue overgrowth from chronic growth hormone excess, almost always caused by a GH-secreting pituitary adenoma, diagnosed with an elevated IGF-1 confirmed by failure of GH suppression on an oral glucose tolerance test. First-line treatment is transsphenoidal resection of the pituitary tumor, with somatostatin analogues, pegvisomant, or cabergoline for persistent disease.
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What this article covers
- Overview
Acromegaly is chronic growth hormone (GH) excess in an adult with fused epiphyses, causing progressive enlargement of acral and soft tissues rather than linear growth.
- Epidemiology
Rare disease of middle adulthood, typically diagnosed in the fourth to sixth decade because of the slow evolution of physical changes.
- Risk factors
Sporadic somatotroph adenoma with no identifiable predisposing condition is the risk profile in the great majority of patients.
- Pathophysiology
Autonomous GH hypersecretion from somatotroph tumor cells escapes the normal negative feedback from hypothalamic somatostatin and target-organ IGF-1.
- Clinical features
Progressive acral and soft-tissue enlargement is the hallmark: enlarging hands, feet, and rings/shoes/hats that no longer fit, together with coarsening facial features, frontal bossing, prognathism…
- Differential diagnosis
Familial tall stature/constitutional gigantism (in a child with suspected gigantism): normal GH axis and normal IGF-1, unlike gigantism, in which IGF-1 is elevated and GH fails to suppress.
- Diagnosis
The diagnosis is established biochemically, not by imaging: an elevated age- and sex-adjusted serum IGF-1 is the best screening test, and the diagnosis is confirmed by failure of GH to suppress below…
- Management
First action is diagnostic and surgical planning, not medical therapy: after biochemical confirmation and pituitary MRI, refer for transsphenoidal resection of the GH-secreting adenoma, which is the…
- Complications
Cardiomyopathy with diastolic dysfunction and left ventricular hypertrophy is the most common cause of death in acromegaly.
- Prognosis
Survival among untreated or poorly treated patients is reduced by an average of 10 years compared with age-matched controls, driven mainly by cardiovascular, cerebrovascular, and respiratory deaths.
- Prevention
There is no primary prevention for sporadic GH-secreting pituitary adenomas; prevention efforts focus on early detection and comorbidity screening once the diagnosis is confirmed.
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