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GTR Home > Conditions/Phenotypes > Severe neonatal-onset encephalopathy with microcephaly

Severe neonatal-onset encephalopathy with microcephaly

Synonyms
Encephalopathy, neonatal severe; Encephalopathy, neonatal severe, due to MECP2 mutations
Modes of inheritance
X-linked recessive inheritance (Orphanet)

Summary

Excerpted from the GeneReview: MECP2 Disorders
The spectrum of MECP2-related phenotypes in females ranges from classic Rett syndrome to variant Rett syndrome with a broader clinical phenotype (either milder or more severe than classic Rett syndrome) to mild learning disabilities; the spectrum in males ranges from severe neonatal encephalopathy to pyramidal signs, parkinsonism, and macroorchidism (PPM-X) syndrome to severe syndromic/nonsyndromic intellectual disability. Females: Classic Rett syndrome, a progressive neurodevelopmental disorder primarily affecting girls, is characterized by apparently normal psychomotor development during the first six to 18 months of life, followed by a short period of developmental stagnation, then rapid regression in language and motor skills, followed by long-term stability. During the phase of rapid regression, repetitive, stereotypic hand movements replace purposeful hand use. Additional findings include fits of screaming and inconsolable crying, autistic features, panic-like attacks, bruxism, episodic apnea and/or hyperpnea, gait ataxia and apraxia, tremors, seizures, and acquired microcephaly. Males: Severe neonatal-onset encephalopathy, the most common phenotype in affected males, is characterized by a relentless clinical course that follows a metabolic-degenerative type of pattern, abnormal tone, involuntary movements, severe seizures, and breathing abnormalities. Death often occurs before age two years.
Full text of GeneReview (by section):
Summary
GeneReview Scope
Diagnosis
Clinical Characteristics
Genetically Related (Allelic) Disorders
Differential Diagnosis
Management
Genetic Counseling
Resources
Molecular Genetics
Chapter Notes
References
Authors:
Simranpreet Kaur
John Christodoulou
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Available tests

79 tests are in the database for this condition.

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Clinical tests (79 available)

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: AUTSX3, MRX16, MRX79, MRXS13, MRXSL, PPMX, RS, RTS, RTT, MECP2
    Summary: methyl-CpG binding protein 2

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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