Which are the symptoms of McCune Albright?

Symptoms of McCune Albright

McCune Albright syndrome (MAS) is a rare genetic disorder that affects multiple systems in the body. It is caused by a mutation in the GNAS gene, which leads to the overactivity of certain hormones and abnormal growth of tissues. The symptoms of McCune Albright can vary widely from person to person, but there are some common features that are often seen in individuals with this condition.

1. Bone Abnormalities

One of the hallmark features of McCune Albright syndrome is the presence of bone abnormalities. These can include uneven growth of bones, bone deformities, and fractures. The bones may be weaker than normal, making them more prone to fractures. The most commonly affected bones are the long bones of the legs, but other bones can also be involved.

2. Skin Pigmentation

Another characteristic feature of McCune Albright syndrome is the presence of skin pigmentation abnormalities. These can manifest as irregular patches of light brown to dark brown skin, known as café-au-lait spots. These spots are typically present at birth or develop in early childhood. The size, shape, and distribution of these spots can vary.

3. Endocrine Abnormalities

McCune Albright syndrome can also affect the endocrine system, which is responsible for producing and regulating hormones in the body. Hormonal abnormalities can lead to various symptoms, including:

• Precocious Puberty: This is the early onset of puberty, which can occur in girls as young as 2-3 years old and in boys as young as 4-5 years old. It is characterized by the development of secondary sexual characteristics, such as breast development and pubic hair growth, before the age of 8 in girls and 9 in boys.


• Thyroid Problems: Some individuals with McCune Albright syndrome may develop an overactive thyroid gland (hyperthyroidism) or an underactive thyroid gland (hypothyroidism).


• Excessive Growth Hormone: In rare cases, excessive production of growth hormone can lead to gigantism or acromegaly, which are characterized by excessive growth and enlargement of certain body parts.

4. Hormone-Related Disorders

McCune Albright syndrome can also be associated with other hormone-related disorders, including:

• Cushing Syndrome: This condition occurs when there is an excess of cortisol hormone in the body. It can cause weight gain, high blood pressure, diabetes, and thinning of the skin.


• Hyperparathyroidism: Some individuals with McCune Albright syndrome may develop overactive parathyroid glands, leading to high levels of calcium in the blood.

5. Other Manifestations

In addition to the above symptoms, individuals with McCune Albright syndrome may also experience other manifestations, such as:

• Early-Onset Bone Pain: Some individuals may experience bone pain from an early age, which can be chronic and debilitating.


• Abnormalities of the Reproductive System: Females may have irregular menstrual periods or develop ovarian cysts.


• Cardiovascular Abnormalities: Rarely, individuals with McCune Albright syndrome may have abnormalities of the heart or blood vessels.


• Neurological Symptoms: In some cases, neurological symptoms like headaches, seizures, or developmental delays may be present.

It is important to note that the severity and combination of symptoms can vary greatly among individuals with McCune Albright syndrome. Some individuals may have only mild manifestations, while others may experience more severe complications. Early diagnosis and appropriate management can help in minimizing the impact of the condition on an individual's health and quality of life.