U.S. flag

An official website of the United States government

Format

Send to:

Choose Destination

Aicardi-Goutieres syndrome 3(AGS3)

MedGen UID:
324389
Concept ID:
C1835916
Disease or Syndrome
Synonym: Aicardi-Goutieres Syndrome 3
 
Gene (location): RNASEH2C (11q13.1)
 
Monarch Initiative: MONDO:0012471
OMIM®: 610329

Disease characteristics

Excerpted from the GeneReview: Aicardi-Goutières Syndrome
Most characteristically, Aicardi-Goutières syndrome (AGS) manifests as an early-onset encephalopathy that usually, but not always, results in severe intellectual and physical disability. A subgroup of infants with AGS present at birth with abnormal neurologic findings, hepatosplenomegaly, elevated liver enzymes, and thrombocytopenia, a picture highly suggestive of congenital infection. Otherwise, most affected infants present at variable times after the first few weeks of life, frequently after a period of apparently normal development. Typically, they demonstrate the subacute onset of a severe encephalopathy characterized by extreme irritability, intermittent sterile pyrexias, loss of skills, and slowing of head growth. Over time, as many as 40% develop chilblain skin lesions on the fingers, toes, and ears. It is becoming apparent that atypical, sometimes milder, cases of AGS exist, and thus the true extent of the phenotype associated with pathogenic variants in the AGS-related genes is not yet known. [from GeneReviews]
Authors:
Yanick J Crow   view full author information

Additional descriptions

From OMIM
Aicardi-Goutieres syndrome is an autosomal recessive disorder characterized by onset of encephalopathy in the first year of life following normal early development. Affected infants typically show extreme irritability, intermittent unexplained fever, chilblains, progressive microcephaly, spasticity, dystonia, and profound psychomotor retardation. Laboratory studies show lymphocytosis and raised titers of alpha-interferon in the cerebrospinal fluid. Brain imaging may show white matter abnormalities, intracerebral calcifications, and cerebral atrophy. Many patients die in childhood (summary by Vogt et al., 2013). For a general phenotypic description and a discussion of genetic heterogeneity of Aicardi-Goutieres syndrome, see AGS1 (225750).  http://www.omim.org/entry/610329
From MedlinePlus Genetics
As a result of the severe neurological problems that are usually associated with Aicardi-Goutières syndrome, most people with this disorder do not survive past childhood. However, some affected individuals with the later-onset form of the condition and milder neurological problems can live into adolescence or adulthood.

People with the later-onset form of Aicardi-Goutières syndrome typically have normal development in infancy. In these individuals, encephalopathy typically occurs after 1 year of age. Similar to those with the early-onset form, babies with the later-onset form experience irritability, poor feeding, and sterile pyrexias. Over time, affected individuals show developmental delays and regression. They may also have spasticity and hypotonia, and the growth of the brain and head may slow leading to microcephaly. The health and developmental problems in people with the later-onset form are typically not as severe as those in individuals with the early-onset form, though the severity can vary among affected individuals.

In about 20 percent of cases, the early-onset form of Aicardi-Goutières syndrome begins prenatally. Slow growth (intrauterine growth retardation) and brain abnormalities, especially brain calcification, may be seen on ultrasound imaging. These individuals have the most severe neurological problems and the highest risk for early death.

About 40 percent of people with the early-onset form of Aicardi-Goutières syndrome develop a skin problem called chilblains. Chilblains are painful, itchy skin lesions that are puffy and red, and they usually appear on the fingers, toes, nose, and ears. They are caused by inflammation of small blood vessels and may be brought on or made worse by exposure to cold temperatures. 

In some affected newborns, white blood cells, interferon proteins, and other immune system molecules can be detected in the cerebrospinal fluid, which is the fluid that surrounds the brain and spinal cord (central nervous system). These findings are consistent with inflammation and tissue damage in the central nervous system.

Some newborns have a combination of features that include an enlarged liver and spleen (hepatosplenomegaly), elevated blood levels of liver enzymes, and a shortage of blood cells called platelets that are needed for normal blood clotting (thrombocytopenia). They may develop intermittent fevers in the absence of infection (sterile pyrexias). While this combination of signs and symptoms is typically associated with the immune system's response to a viral infection that is present at birth (congenital), no actual infection is found in these infants. For this reason, Aicardi-Goutières syndrome is sometimes referred to as a "mimic of congenital infection."

Individuals with the early-onset form of Aicardi-Goutières syndrome can experience severe brain dysfunction (encephalopathy) within the first months of life. This encephalopathic phase of the disorder can last for weeks or months. Affected infants stop developing new skills and begin losing skills they had already acquired (developmental regression). Infants with this form can have seizures. Medical imaging reveals loss of white matter in the brain (leukodystrophy). White matter consists of nerve cells covered by myelin, which is a substance that protects nerves and allows them to rapidly transmit nerve impulses. Growth of the brain and skull slows down, resulting in an abnormally small head size (microcephaly). Affected individuals may have abnormal deposits of calcium (calcification) in the brain. As a result of this neurological damage, most people with Aicardi-Goutières syndrome have profound intellectual disabilities.

Aicardi-Goutières syndrome is often divided into two types, which are distinguished by the severity of features and the age at which they begin: the early-onset form (sometimes called the classic form) and the later-onset form. 

Affected babies are usually extremely irritable and do not feed well. They also have muscle stiffness (spasticity), involuntary tensing of various muscles (dystonia), and weak muscle tone (hypotonia). They can have vision problems including vision loss and increased pressure in the eye (glaucoma).

Aicardi-Goutières syndrome is a disorder with variable signs and symptoms, but it primarily affects the brain, the immune system, and the skin.  https://medlineplus.gov/genetics/condition/aicardi-goutieres-syndrome

Clinical features

From HPO
Hepatosplenomegaly
MedGen UID:
9225
Concept ID:
C0019214
Sign or Symptom
Simultaneous enlargement of the liver and spleen.
Dystonic disorder
MedGen UID:
3940
Concept ID:
C0013421
Sign or Symptom
An abnormally increased muscular tone that causes fixed abnormal postures. There is a slow, intermittent twisting motion that leads to exaggerated turning and posture of the extremities and trunk.
Spasticity
MedGen UID:
7753
Concept ID:
C0026838
Sign or Symptom
A motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes with increased muscle tone, exaggerated (hyperexcitable) tendon reflexes.
Encephalopathy
MedGen UID:
39314
Concept ID:
C0085584
Disease or Syndrome
Encephalopathy is a term that means brain disease, damage, or malfunction. In general, encephalopathy is manifested by an altered mental state.
Hyperreflexia
MedGen UID:
57738
Concept ID:
C0151889
Finding
Hyperreflexia is the presence of hyperactive stretch reflexes of the muscles.
Hypoplasia of the corpus callosum
MedGen UID:
138005
Concept ID:
C0344482
Congenital Abnormality
Underdevelopment of the corpus callosum.
CSF lymphocytic pleiocytosis
MedGen UID:
140894
Concept ID:
C0427877
Laboratory or Test Result
An increased lymphocyte count in the cerebrospinal fluid.
Abnormal cerebral white matter morphology
MedGen UID:
181756
Concept ID:
C0948163
Pathologic Function
An abnormality of the cerebral white matter.
Delayed myelination
MedGen UID:
224820
Concept ID:
C1277241
Finding
Delayed myelination.
Severe global developmental delay
MedGen UID:
332436
Concept ID:
C1837397
Finding
A severe delay in the achievement of motor or mental milestones in the domains of development of a child.
Thrombocytopenia
MedGen UID:
52737
Concept ID:
C0040034
Disease or Syndrome
A reduction in the number of circulating thrombocytes.
Hypotonia
MedGen UID:
10133
Concept ID:
C0026827
Finding
Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist.
Cerebral calcification
MedGen UID:
124360
Concept ID:
C0270685
Finding
The presence of calcium deposition within the cerebrum.
Progressive microcephaly
MedGen UID:
340542
Concept ID:
C1850456
Anatomical Abnormality
Progressive microcephaly is diagnosed when the head circumference falls progressively behind age- and gender-dependent norms.
Generalized hypotonia
MedGen UID:
346841
Concept ID:
C1858120
Finding
Generalized muscular hypotonia (abnormally low muscle tone).
Chilblains
MedGen UID:
886
Concept ID:
C0008058
Injury or Poisoning
Chilblains, also called perniosis, are an inflammatory skin condition related to an abnormal vascular response to the cold. We are unaware of a reliable estimate of incidence. It typically presents as tender, pruritic red or bluish lesions located symmetrically on the dorsal aspect of the fingers, toes, ears and nose. Less commonly, reports describe involvement of the thighs and buttocks. The lesions present hours after exposure to cold and usually resolve spontaneously in one to three weeks.
Elevated circulating hepatic transaminase concentration
MedGen UID:
116013
Concept ID:
C0235996
Finding
Elevations of the levels of SGOT and SGPT in the serum. SGOT (serum glutamic oxaloacetic transaminase) and SGPT (serum glutamic pyruvic transaminase) are transaminases primarily found in the liver and heart and are released into the bloodstream as the result of liver or heart damage. SGOT and SGPT are used clinically mainly as markers of liver damage.
Nystagmus
MedGen UID:
45166
Concept ID:
C0028738
Disease or Syndrome
Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms.

Recent clinical studies

Diagnosis

Ramaekers VT, Blau N
Dev Med Child Neurol 2004 Dec;46(12):843-51. doi: 10.1017/s0012162204001471. PMID: 15581159

Clinical prediction guides

Wang Q, Han Y, Zhou X, Cheng S, Wang X, Chen X, Yuan H
Clin Genet 2023 Aug;104(2):259-265. Epub 2023 Apr 24 doi: 10.1111/cge.14343. PMID: 37092250
Ramaekers VT, Blau N
Dev Med Child Neurol 2004 Dec;46(12):843-51. doi: 10.1017/s0012162204001471. PMID: 15581159

Supplemental Content

Recent activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...