Acromegaly

Acromegaly (from Greek akros "extreme" or "extremities" and megalos "large" - extremities enlargement) is a disease of adults, in which excessive secretions from the pituitary gland produces excessive growth hormone. In a majority of cases, excess growth hormone is produced by a pituitary adenoma (a benign tumour of the pituitary gland). This condition can occur in childhood, when it may result in a gigantism but in adult life it usually occurs in the middle or old age. It affects women and men equally.

The characteristic features of the disease are disproportionate enlargement of parts of the skeleton including the ears, nose, jaw, fingers and toes - together with soft tissue overgrowth.

Acromegaly can be complicated by other endocrine disturbances, such as diabetes mellitus and hypothyroidism.

This condition is rare - the annual incidence is about 3 cases per million population (USA statistics). It was first recognised by P Marie in 1886.

The development of symptoms is insidious. Early diagnosis may be missed until the symptoms are so pronounced that they have already made a marked disturbance on the patient daily lifestyle

Characteristics include:

• Gradual, marked enlargement and elongation of the bones of the face, jaw, and extremities hands and feet
• The skin becomes coarse and thick
• Visual disturbance
• Headache
• Muscle weakness
• Curvature of the spine (kyphosis)
• Arthritis
• Diabetes Mellitus may develop
• Sweating is common
• Swelling of the soft tissues of the body, the tongue becomes enlarged and the lips, nose and ears become conspicuous

The type of treatment chosen depends on individual cases, the extent of damage, and the size of the pituitary tumour. While some treatment methods used to treat this condition may be used on their own, a combination of these treatments may be required to successfully treat the patient.

Some drug therapies have been shown to successfully to reduce the growth hormone concentrations, and the size of the tumour. Surgery which may involve partial removal of the pituitary gland can be successful, especially in patients with small pituitary tumours. Surgery cures a smaller proportion of large tumours, and the chances of remission are less than 20 percent.

Another method of treatment of acromegaly, known as external beam irradiation may reduce growth hormone levels in some 90 percent of patients. It has been shown to prevent regrowth of the tumour in 99 percent of cases, although the treatment is slow. While the biggest fall of hormone levels occurs within the first two years of treatment, the level will continue to fall for up to 15 years. Hypopituitarism is the most common side-effect of radiotherapy, therefore it is important for patients to have two yearly check-ups for pituitary function for the rest of their lives.