OVERVIEW

What is adolescent goiter?

Adolescent goiter is a type of simple goiter. As the name suggests, it refers to the occurrence of simple thyroid enlargement during adolescence, primarily seen in girls.

During puberty, as the body grows rapidly, the demand for thyroid hormones increases. If the thyroid's "production" speed cannot keep up with this demand, varying degrees of thyroid enlargement may occur. An iodine uptake test may show increased thyroid iodine absorption. However, since thyroid function remains normal and iodine absorption speed does not accelerate, adolescent goiter—though similar to hyperthyroidism in presenting thyroid enlargement and increased iodine uptake—does not exhibit an early iodine absorption peak. In simpler terms, it is "large but not strong."

Most adolescent goiters resolve on their own, but small doses of thyroid hormone may be administered for significant enlargement.

What is simple goiter?

Simple goiter occurs when the thyroid gland enlarges (visible and palpable) due to certain reasons but without functional changes (thyroid function tests remain normal). In simpler terms, it is "large but useless."

In contrast, if the thyroid is both enlarged and hyperactive, it is called "toxic goiter."

Is adolescent goiter common?

There is currently a lack of specific epidemiological data on adolescent goiter. This condition is more common in females.

Is adolescent goiter the same as "big neck disease"?

Both adolescent goiter and "big neck disease" are types of simple goiter, meaning the thyroid is enlarged but functions normally—colloquially, "large but useless."

However, their causes and mechanisms differ significantly:

• Adolescent goiter results from increased thyroid hormone demand during puberty. When the thyroid's "production capacity" cannot meet this demand, goiter occurs.

• "Big neck disease" (endemic goiter) is caused by iodine deficiency in the diet. It is regionally prevalent, hence the name "endemic goiter." It is widespread globally, mainly in inland, high-altitude mountainous areas, such as southwestern, northwestern, and northern regions of China.

What is the thyroid?

The thyroid is located in the front lower part of the neck. Its primary function is to use dietary iodine to synthesize and secrete thyroid hormones, regulating and promoting metabolism and growth.

Normally, the thyroid is "hidden" behind neck muscles, so it is neither visible nor palpable under healthy conditions.

What is adolescence?

Adolescence is the transitional period from childhood to adulthood, marked by the appearance of secondary sexual characteristics (e.g., Adam's apple, facial hair, voice changes in boys; breast development, pubic hair growth in girls) and the gradual maturation of reproductive function. The World Health Organization defines adolescence as ages 10–20.

SYMPTOMS

What are the common manifestations of adolescent goiter?

The main symptom is thyroid enlargement. In most cases of adolescent goiter, the swelling is not severe and usually causes no obvious discomfort. It is often discovered incidentally when looking in the mirror or when others notice a fuller or thicker neck.

What serious consequences can adolescent goiter cause?

Most adolescent goiters resolve on their own and do not lead to serious consequences.

In rare cases, significant thyroid enlargement may cause compression symptoms, such as:

• Tracheal compression, leading to throat tightness, chronic irritating dry cough, breathlessness, or difficulty breathing;

• Esophageal compression, causing difficulty swallowing;

• Recurrent laryngeal nerve compression, resulting in hoarseness, spasmodic cough, or loss of voice;

• Cervical sympathetic nerve compression, which may cause one-sided pupil dilation or, in severe cases, Horner's syndrome, characterized by sunken eyeball, constricted pupil, and drooping upper eyelid;

• If the thyroid is ectopic (e.g., located behind the sternum or in the chest cavity), enlargement may lead to superior vena cava syndrome, presenting as unilateral facial or upper limb swelling.

CAUSES

What are the causes of adolescent goiter?

During adolescence, the body's growth and development accelerate, increasing the demand for thyroid hormones. If the thyroid gland's "production" speed cannot keep up with this demand, varying degrees of thyroid enlargement may occur, leading to adolescent goiter.

Who is most commonly affected by adolescent goiter?

Adolescent goiter is most commonly seen in girls aged 10 to 20.

Is adolescent goiter contagious?

Adolescent goiter is not a contagious disease and cannot be transmitted.

Is adolescent goiter hereditary?

Currently, there is no data indicating that adolescent goiter is hereditary.

DIAGNOSIS

How is adolescent goiter diagnosed?

Doctors mainly refer to the following characteristics for diagnosis:

• Children in the adolescent stage;

• Presence of varying degrees of thyroid enlargement;

• Normal thyroid function in blood tests.

What tests are needed for patients with adolescent goiter?

Generally, blood tests for thyroid function, thyroid antibodies, and thyroid ultrasound are required.

• Thyroid function: Includes free triiodothyronine (FT3), free thyroxine (FT4), triiodothyronine (T3), thyroxine (T4), and thyroid-stimulating hormone (TSH) to assess thyroid function and rule out hyperthyroidism or hypothyroidism.

• Thyroid-related antibodies: Includes anti-thyroglobulin antibody (TgAb) and anti-thyroid peroxidase antibody (TPOAb). Elevated antibodies suggest possible thyroiditis, indicating it is not a simple adolescent goiter.

• Thyroid ultrasound: Used to evaluate the thyroid's position, size, shape, internal structure, and detect nodules, liquefaction, or calcification.

• Other tests: - Radioactive iodine uptake test: Helps differentiate from hyperthyroidism when diagnosis is unclear. - Thyroid imaging: If ultrasound reveals large thyroid nodules, this test provides further details. - Thyroid CT or MRI: Used for significant compression symptoms or retrosternal thyroid to assess the thyroid's relationship with adjacent tissues and its extension into the chest.

What should patients with adolescent goiter pay attention to during thyroid-related tests?

No special preparation is needed for thyroid function tests, thyroid antibody tests, or thyroid ultrasound. Fasting is not required.

Which diseases can adolescent goiter be easily confused with?

Since both present with thyroid enlargement, adolescent goiter may be confused with hyperthyroidism. Doctors differentiate them through thyroid function and radioactive iodine uptake tests.

• Adolescent goiter: Lacks hyperthyroidism symptoms like heat intolerance, sweating, palpitations, weight loss, frequent bowel movements, or exophthalmos. Thyroid function tests are normal, and iodine uptake may increase but without peak advancement—described as "large but not strong."

• Hyperthyroidism: Shows the above hyperthyroidism symptoms. Thyroid function tests reveal elevated T3/T4 and decreased TSH. Iodine uptake is both increased and peaks early—described as "large and strong."

TREATMENT

Which department should I visit for adolescent goiter?

Endocrinology or general internal medicine.

Can adolescent goiter heal on its own?

Most adolescent goiters can resolve spontaneously, meaning they often heal on their own. A small number of cases may persist into adulthood and remain long-term.

How is adolescent goiter treated?

Adolescent goiter usually does not require special treatment, as most cases can heal naturally.

For a small number of cases with significant thyroid enlargement, thyroid hormone replacement therapy may be given to suppress further enlargement. Commonly used medications include levothyroxine tablets (such as Euthyrox, Letrox, or Jiaheng), aiming to keep thyroid-stimulating hormone (TSH) levels at the lower end of the normal range.

In very rare cases where the thyroid is significantly enlarged, causing compression symptoms, or for retrosternal goiters, surgical treatment may be performed to remove part of the enlarged thyroid.

Does adolescent goiter require hospitalization?

Hospitalization is generally unnecessary, and outpatient observation and treatment are sufficient.

DIET & LIFESTYLE

What should patients with adolescent goiter pay attention to in their diet?

The recommended daily iodine intake for adolescents is 120 micrograms.

Most areas in China are iodine-deficient regions, with daily iodine intake from drinking water being about 10 micrograms. The general population obtains about 25–50 micrograms of iodine daily from food. Without specifically increasing iodine-rich foods, the iodine obtained from food and water alone cannot meet the body's needs.

According to China's "Iodine Content in Edible Salt" standard, if the iodine fortification level is 25 milligrams per kilogram of salt, with a daily salt intake of 5 grams and a cooking loss rate of 20% (as recommended by the WHO and other international organizations), the daily iodine intake from iodized salt would be 100 micrograms. Combined with iodine from water and food, this meets the daily iodine requirement for adolescents.

Consuming iodized salt is a continuous, convenient, economical, and practical way to supplement iodine. Therefore, except for residents in water-source high-iodine areas who should avoid iodized salt, others, including adolescents, should consume iodized salt.

Certain foods, such as cabbage and cassava (mainly cruciferous plants), may release substances that cause goiter. If adolescent goiter is confirmed, these foods should be avoided.

Does adolescent goiter affect fertility?

Most adolescent goiters resolve on their own and do not affect fertility.

PREVENTION

How to prevent adolescent goiter?

Prevention of adolescent goiter mainly includes:

• Avoid excessive consumption of goitrogenic substances, such as cabbage and cassava;

• Maintain an ideal daily iodine intake by consuming iodized salt.