Acromegaly

Acromegaly is a rare condition in which the body produces an excess of growth hormone, beginning after the growth plates in the bones have fused at the end of puberty. (When the production of excess growth hormone begins in childhood or adolescence, before growth plates have fused, the condition is known as gigantism.) 

Because acromegaly begins after childhood and adolescent growth has finished, the condition does not affect a person’s height. Instead, it causes abnormal growth of the bones in the hands, feet and face. It can also affect other body systems.

Symptoms of acromegaly may include:

• Growth of the hands and feet in adulthood (sometimes noticed as a change in shoe size or the tightness of rings)
• Enlargement of the nose, lips and tongue
• Bone changes in the face, such as growing prominence of the jaw or forehead
• Thickened, coarse and oily skin • Increased sweating and body odor
• Emerging gaps between the teeth
• Joint pain • Fatigue and muscle weakness
• Deepened, husky voice
• Headaches
• Sleep apnea and snoring
• Vision problems
• Irregular menstruation in women
• Erectile dysfunction in men
• Enlargement of the heart or other organs
• Polyps on the lining of the colon

Growth hormone is produced by the pituitary gland, a pea-sized gland located at the base of the brain. Growth hormone in the blood acts as a signal to the liver to produce another hormone, insulin-like growth factor (1 IGF-1), which drives bone and tissue growth. In most cases, acromegaly is caused by a benign adenoma or growth (noncancerous) pituitary tumor. More rarely, the condition is caused by a tumor in another part of the body.

Genetic mutations can be associated with the formation of pituitary tumors leading to acromegaly, especially in young adults. These genetic mutations are sometimes inherited, which means the condition can run in families. More commonly, though, the mutations occur spontaneously, without being inherited from either parent, or the condition does not have an identifiable genetic association.

Because acromegaly symptoms can develop slowly, over several years, it can take time for the condition to be noticed and diagnosed. If acromegaly is suspected, based on physical symptoms, your doctor may refer you to an endocrinologist, who will:

• Take a complete medical history to understand the occurrence of symptoms
• Perform a physical exam

The endocrinologist may also:

• Order blood tests to check for high levels of growth hormone. These tests may include:
  • Growth hormone and insulin-like growth factor (1 IGF-1) blood tests.
  • An oral glucose tolerance test (OGTT), which can detect the presence of a pituitary tumor.
• Order imaging studies, such as magnetic resonance imaging (MRI) or computed tomography (CT) to locate and measure the tumor suspected of causing the problem

Additional tests may be performed to check for heart problems, sleep apnea or polyps in the colon, or to measure bone mineral density

Treatment for acromegaly focuses on:

• Controlling elevated levels of growth hormone and insulin-like growth factor
• Managing the pituitary tumor growth
• Addressing the effects of excessive growth hormone on other body systems
• Addressing any effects of pituitary tumor growth on nearby brain and nerve structures

Treatment may include:

• Surgery to remove a pituitary tumor. Surgeons may reach the tumor through an incision in the upper lip or at the bottom of the nose, or by cutting through the skull.
• Surgery to remove a tumor elsewhere on the body that is affecting the production of growth hormone.
• Drug therapy to control the over-production of growth hormones or reduce their effect on receptor cells.
• Radiation therapy to kill tumor cells or to keep them from growing.
• Radiation therapy for a pituitary tumor must be narrowly targeted to minimize damage to nearby brain tissue.

Follow-up care

Patients with acromegaly will need regular follow-up visits with their primary doctor or endocrinologist to check that hormone levels are maintained in a healthy range and to manage any complications related to the condition. Complications can include hypertension, cardiomyopathy, obstructive sleep apnea, joint problems and susceptibility to bone fractures. 

Treatment of acromegaly at Children’s Hospital of Philadelphia (CHOP) is managed by the Neuroendocrine Center, a multidisciplinary center created to treat children with conditions that require expertise from the Division of Endocrinology and Diabetes, Neurosurgery, Neuro-oncology, Neuro-ophthalmology and Neuroradiology.

If needed for care, the Neuroendocrine Center also collaborates with specialists from Genetics, Pathology, the Cancer Survivorship Program, the Growth Center, the Adrenal and Puberty Center and the Healthy Weight Program. We also work closely with colleagues from the Hospital of the University of Pennsylvania’s Pituitary Center, who focus on pituitary disease in adults. 

The long-term outlook for patients with acromegaly depends on how soon they are diagnosed and begin treatment, how effective the treatment is in reducing hormone levels and the presence of complications related to the condition. In general, early diagnosis and treatment lead to better outcomes and fewer complications.