Aicardi-Goutieres syndrome 5

Synonyms

AGS5
SAMHD1-related Aicardi-Goutieres syndrome

Overview

Aicardi-Goutieres syndrome type 5 is a form of Aicardi-Goutieres syndrome, a genetically heterogeneous condition characterised by cerebral atrophy, leukoencephalopathy, intracranial calcifications, chronic cerebrospinal fluid (CSF) lymphocytosis, increased CSF alpha-interferon, and negative serology for prenatal infection—despite clinical features (thrombocytopaenia, hepatosplenomegaly and elevated hepatic transaminases, and intermittent fever) suggesting an infection. Severe neurologic defects present in infancy (e.g., microcephaly, spasticity, dystonic posturing, profound psychomotor retardation), usually leading to death in early childhood.

Symptoms

  • Encephalopathy
  • Spastic quadriplegia
  • Severe mental retardation
  • Progressively small head Irritability
  • Irritability
  • Seizures
  • Increased or decreased muscle tone
  • Spasticity
  • Dystonic posturing
  • Severe psychomotor retardation
  • Calcification of basal ganglia
  • Thrombocytopenia
  • Enlarged liver
  • Enlarged spleen
  • Increased liver transaminases
  • Intermittent fever
  • Vegetative state
  • Early death
  • Cognitive impairment
  • Holoprosencephaly
  • Hypertonia
  • Porencephaly

Causes

There are six different types of Aicardi-Goutieres syndrome, which are distinguished by the gene that causes the condition: TREX1, RNASEH2A, RNASEH2B, RNASEH2C, SAMHD1, and ADAR genes. Most cases are inherited in an autosomal recessive pattern, although rare autosomal dominant cases have been reported.

Later work mapped the Aicardi-Goutieres syndrome to chromosome 3p21 and suggested that the two, along with the pseudo-TORCH (toxoplasmosis, rubella, cytomegalovirus, and herpes simplex virus types 1 and 2) syndrome were the same disorder.

Treatment

Treatment is symptomatic and supportive. 

Resources

  • NIH