From OMIM
Aicardi-Goutieres syndrome (AGS) is a genetically heterogeneous encephalopathy characterized in its most severe form by cerebral atrophy, leukodystrophy, intracranial calcifications, chronic cerebrospinal fluid (CSF) lymphocytosis, increased CSF alpha-interferon (IFNA1; 147660), and negative serologic investigations for common prenatal infections (Ali et al., 2006). AGS is phenotypically similar to in utero viral infection. Severe neurologic dysfunction becomes clinically apparent in infancy, and manifests as progressive microcephaly, spasticity, dystonic posturing, profound psychomotor retardation, and often death in early childhood. Outside the nervous system, thrombocytopenia, hepatosplenomegaly, and elevated hepatic transaminases along with intermittent fever may also erroneously suggest an infective process (Crow et al., 2006). In a review of AGS, Stephenson (2008) noted that an expanded phenotypic spectrum has been recognized and that most of the original criteria for diagnosis no longer apply: affected individuals may show later onset and may not have severe or progressive neurologic dysfunction, calcification of the basal ganglia, or CSF lymphocytosis. The appearance of chilblains is an important clinical sign for correct diagnosis. The most severe neonatal form of AGS is typically due to mutation in the TREX1 gene. Cree encephalitis was originally considered a separate disorder, but genetic evidence has shown that it is the same as AGS1. See also pseudo-TORCH syndrome (251290), which shows phenotypic overlap and may in some cases represent AGS (Crow et al., 2000; Crow et al., 2003). AGS is distinct from the similarly named Aicardi syndrome (304050), which is characterized by agenesis of the corpus callosum, spinal skeletal abnormalities, and chorioretinal abnormalities. Genetic Heterogeneity of Aicardi-Goutieres Syndrome See also AGS2 (610181), caused by mutation in the gene encoding subunit B of ribonuclease H2 (RNASEH2B; 610326) on chromosome 13q14; AGS3 (610329), caused by mutation in the RNASEH2C gene (610330) on chromosome 11q13; AGS4 (610333), caused by mutation in the RNASEH2A gene (606034) on chromosome 19p13; AGS5 (612952), caused by mutation in the SAMHD1 gene (606754) on chromosome 20q11; AGS6 (615010), caused by mutation in the ADAR1 gene (146920) on chromosome 1q21; AGS7 (615846), caused by mutation in the IFIH1 gene (606951) on chromosome 2q24; AGS8 (619486), caused by mutation in the LSM11 gene (617910) on chromosome 5q33; and AGS9 (619487), caused by mutation in the RNU7-1 gene (617876) on chromosome 12p13.  http://www.omim.org/entry/225750

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."

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).

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. 

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