What Causes Acromegaly? Understanding the Origins and Symptoms of Excess Growth Hormone

Acromegaly is a rare hormonal disorder that primarily affects adults after the closure of their epiphyseal growth plates. Unlike gigantism, which occurs in children before bone growth stops, acromegaly develops when the body produces too much growth hormone (GH) in adulthood. This overproduction leads to gradual and often subtle physical changes that can go unnoticed for years.

Primary Cause: Pituitary Tumors

The most common cause of acromegaly is a benign tumor in the pituitary gland, known as a pituitary adenoma. These non-cancerous growths develop in the anterior pituitary and secrete excessive amounts of growth hormone. Over 95% of acromegaly cases are linked to such tumors. Although they are typically slow-growing, their persistent activity disrupts normal hormonal balance.

In rare instances, acromegaly may result from tumors located outside the pituitary gland—such as in the lungs, pancreas, or adrenal glands—that produce either growth hormone or growth hormone-releasing hormone (GHRH). However, these ectopic sources account for only a small fraction of diagnosed cases.

Recognizing the Physical Signs

One of the hallmark features of acromegaly is its distinct impact on appearance. Because excess GH stimulates tissue and bone growth, patients often develop noticeable facial changes over time.

Common Physical Manifestations Include:

Enlarged hands and feet: Rings may no longer fit, and shoe sizes increase without explanation.
Protruding jaw (prognathism): The lower jaw extends forward, altering facial symmetry.
Widely spaced teeth: As the jawbone grows, gaps form between teeth despite good dental hygiene.
Deep, husky voice: Thickened vocal cords lead to voice changes.
Coarse facial features: The nose, lips, and forehead may become more prominent.

These symptoms usually progress slowly, which is why many individuals do not seek medical attention until significant changes have occurred.

Treatment Options and Management

Early diagnosis and treatment are crucial in preventing long-term complications such as diabetes, hypertension, heart disease, and arthritis. The primary treatment for pituitary-derived acromegaly is surgical removal of the tumor via a transsphenoidal approach—a minimally invasive procedure performed through the nose.

If surgery isn't fully effective or isn't an option, doctors may recommend additional therapies, including:

Medication: Somatostatin analogs (like octreotide or lanreotide), dopamine agonists, or GH receptor antagonists (such as pegvisomant) help control hormone levels.
Radiation therapy: Used in select cases to shrink residual tumor tissue when surgery and drugs are insufficient.

Regular monitoring of hormone levels and imaging studies are essential for long-term management and ensuring optimal outcomes.

While acromegaly is uncommon, understanding its root causes and recognizing early signs can lead to timely intervention. Increased awareness among both patients and healthcare providers improves the chances of successful treatment and enhanced quality of life.