What is macroglossia

Macroglossia is an abnormally large tongue in proportion to other structures in the mouth. Macroglossia can be associated with a wide range of congenital (present from birth) and acquired conditions, or it can occur as an isolated feature (with no other abnormalities). In most cases, macroglossia is due to vascular malformations (blood vessel abnormalities) and muscular hypertrophy (an increase in muscle mass) ¹.

Symptoms associated with macroglossia may include drooling; speech impairment; difficulty eating; stridor; snoring; airway obstruction; abnormal growth of the jaw and teeth; ulceration; and/or dying tissue on the tip of the tongue ². The tongue may protrude from the mouth.

Congenital or inherited causes of macroglossia may include various syndromes (e.g. Beckwith-Wiedemann syndrome or Down syndrome); hemangioma; congenital hypothyroidism; primary amyloidosis; mucopolysaccharidosis; and neurofibromatosis.

In some cases, macroglossia occurs as an isolated hereditary trait that is inherited in an autosomal dominant manner ³.

Isolated autosomal dominant macroglossia is very rare, with about 50 cases reported in the medical literature ⁴. The prevalence in other instances depends on the underlying disorder for which the macroglossia is secondary. For example, macroglossia occurs in most cases of Beckwith-Wiedemann syndrome, and the prevalence of that syndrome is estimated at 1 in 17,000 births ⁴. Using the Kids’ Inpatient Database, a study by Simmonds et al. ⁵ reported congenital macroglossia to be present in 4.63 per 100,000 births, with 48.1% of cases being isolated and 51.9% being syndromic. The aforementioned study by Simmonds et al. found the incidence of isolated congenital macroglossia to be greater in females, with a 1.93 odds ratio ⁵. The aforementioned study by Simmonds et al. found the incidence of isolated congenital macroglossia to be greater in African Americans, with a 2.02 odds ratio ⁵.

Acquired causes may include metabolic or endocrine disorders such as hypothyroidism, amyloidosis, and acromegaly; inflammatory or infectious diseases such as pemphigus vulgaris, diphtheria, tuberculosis, and sarcoidosis; cancer and trauma.

Neoplastic conditions (involving abnormal or uncontrolled cell growth) may also cause macroglossia, such as lymphangioma or various malignancies (cancers) ¹.

Specialists that may be involved in assessing or treating a person with macroglossia may include plastic surgeons or oral and maxillofacial surgeons; orthodontists; otolaryngologists (ear, nose and throat doctors); dentists; and speech and language therapists. People with macroglossia are encouraged to speak with their medical and/or dental healthcare providers who may be able to provide a referral to a specialist with knowledge of the condition.

Macroglossia treatment depends upon the underlying cause and severity and may range from speech therapy in mild cases, to surgical reduction in more severe cases.

Macroglossia causes

Macroglossia can result from a wide range of congenital and acquired conditions, although it is most frequently the product of vascular malformations and muscular hypertrophy. Because of the large number of possible causes, multiple classification schemes have been used to list the causes.

Macroglossia can be seen in certain inherited or congenital (existing at birth) disorders, including:

• Acromegaly (buildup of too much growth hormone in the body)
• Beckwith-Wiedemann syndrome (growth disorder that causes large body size, large organs, and other symptoms)
• Behmel or Laband syndromes
• Congenital hypothyroidism (decreased production of thyroid hormone)
• Diabetes (high blood sugar caused by body producing too little or no insulin)
• Down syndrome (extra copy of chromosome 21, which causes problems with physical and intellectual functioning)
• Idiopathic tongue muscle hypertrophy
• Hamartomas
• Lingual thyroid
• Lymphangioma or hemangioma (malformations in the lymph system or buildup of blood vessels in the skin or internal organs)
• Mucopolysaccharidoses (a group of diseases that cause large amounts of sugar to build up in the body’s cells and tissues)
• Primary amyloidosis (a buildup of abnormal proteins in the body’s tissues and organs)
• Salivary gland tumor

Acquired causes

• Metabolic/endocrine conditions that cause true macroglossia include the following:
• Hypothyroidism ⁶
• Cretinism
• Amyloidosis
• Acromegaly
• Myxedema

Inflammatory/infectious causes of true macroglossia include the following:

• Ludwig angina
• Pemphigus vulgaris
• Diphtheria
• Tuberculosis
• Actinomycosis
• Sarcoidosis
• Candidiasis

Systemic/medical conditions that cause true macroglossia include the following:

• Neurofibromatosis

Traumatic causes of true macroglossia include the following:

• Hemorrhage and hematoma
• Direct trauma (tongue biting)
• Intubation injury

Neoplastic conditions that cause true macroglossia include the following:

• Lymphangioma ⁷
• Hemangioma
• Carcinoma
• Plasmacytoma
• Lymphoma

Macroglossia may be found in individuals affected by certain inherited or congenital disorders including Beckwith-Wiedemann syndrome, acromegaly, primary amyloidosis, congenital hypothyroidism, Down syndrome, Apert syndrome, and many others.

Macroglossia may also be a sign of certain acquired disorders, including malignancies, metabolic/endocrine disorders, and inflammatory or infectious diseases.

In rare cases, macroglossia is an inherited disorder not associated with any other cause, either congenital or acquired. In such instances, the disorder is genetically transmitted as an autosomal dominant trait.

Dominant genetic disorders occur when only a single copy of an abnormal gene is necessary for the appearance of the disease. The abnormal gene can be inherited from either parent, or can be the result of a new mutation (gene change) in the affected individual. The risk of passing the abnormal gene from affected parent to offspring is 50% for each pregnancy regardless of the sex of the resulting child.

Macroglossia signs and symptoms

Macroglossia is a disorder characterized by a tongue that is large in proportion to other structures in the mouth. In the congenital type of the disorder, protrusion of the tongue from the mouth may interfere with feeding of the infant. Later, talking may be affected. The large size of the tongue may also cause abnormal development of the jaw and teeth, resulting in misaligned or protruding teeth. Ulceration and dying tissue on the tip of the tongue may be other symptoms of the disorder.

Macroglossia diagnosis

Infants born with isolated autosomal dominant macroglossia present with the obvious sign at birth. A family history and physical exam can confirm the diagnosis.

While macroglossia may have various causes, a carefully evaluated patient history can typically indicate the cause and determine the types of lab tests that may be needed. Tests may help to confirm a suspected cause or to determine the extent of the abnormality.

Imaging tests for a person with macroglossa may include CT scan and MRI; ultrasonography; panorex (panoramic X-ray) and cephalometric radiograph (image of the head); and/or a barium swallow study. Diagnostic procedures, such as a biopsy or fine needle aspiration, may be performed depending on the suspected cause of macroglossia.

Macroglossia treatment

Medical therapy for macroglossia is useful when the underlying cause is identified, and the cause is medically treatable – such as hypothyroidism, infection, or amyloidosis. No medical treatments have been proven useful when the cause is unclear. Surgery to reduce the size of the tongue may be an option for people with macroglossia. Most studies have shown that surgical procedures for macroglossia lead to improved physical appearance, speech, chewing and feeding ¹.

References

1. Macroglossia. https://emedicine.medscape.com/article/873658-overview
2. Glenn C Isaacson. Congenital anomalies of the jaw, mouth, oral cavity, and pharynx. UpToDate. Waltham, MA: UpToDate; August, 2015
3. Macroglossia. https://rarediseases.org/rare-diseases/macroglossia/
4. Macroglossia. https://rarediseases.org/rare-diseases/macroglossia
5. Simmonds JC, Patel AK, Mildenhall NR, Mader NS, Scott AR. Neonatal Macroglossia: Demographics, Cost of Care, and Associated Comorbidities. Cleft Palate Craniofac J. 2018 Sep. 55 (8):1122-9.
6. Dudhia SB, Dudhia BB. Undetected hypothyroidism: a rare dental diagnosis. J Oral Maxillofac Pathol. 2014 May. 18(2):315-9
7. V U, Sivasankari T, Jeelani S, et al. Lymphangioma of the tongue – a case report and review of literature. J Clin Diagn Res. 2014 Sep. 8(9):ZD12-4.