X-linked hydrocephalus with stenosis of the aqueduct of Sylvius
Findings
No curated finding names X-linked hydrocephalus with stenosis of the aqueduct of Sylvius yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A form of L1 syndrome caused by changes in the L1CAM gene characterized by severe hydrocephalus mostly with prenatal onset, signs of intracranial hypertension, adducted thumbs, spasticity, and severe intellectual deficit. HSAS represents the severe end of the spectrum and is associated with poor prognosis.
Definition from the Mondo Disease Ontology (MONDO:0010611), read 2026-09-29. CC BY 4.0.
- Inheritance
- X-linked recessive inheritance
HPO, annotations 2026-09-02
Features
17 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- HydrocephalusHPOHP:0000238
- 7 of 7 reported patients · Male
- Very frequent (80% to 99% of cases)
- Intellectual disabilityHPOHP:0001249
- 5 of 5 reported patients · Male
- Aqueductal stenosisHPOHP:0002410
- 2 of 5 reported patients · Congenital onset · Male
- Very frequent (80% to 99% of cases)
- Hemiplegia/hemiparesisHPOHP:0004374
- Very frequent (80% to 99% of cases)
- Increased intracranial pressureHPOHP:0002516
- Very frequent (80% to 99% of cases)
- Severe intellectual disabilityHPOHP:0010864
Show the remaining 5
- HoloprosencephalyHPOHP:0001360
- Occasional (5% to 29% of cases)
- Joint stiffnessHPOHP:0001387
- Occasional (5% to 29% of cases)
- NystagmusHPOHP:0000639
- Occasional (5% to 29% of cases)
- SeizureHPOHP:0001250
- Occasional (5% to 29% of cases)
- StrabismusHPOHP:0000486
- Occasional (5% to 29% of cases)
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- L1CAMHGNC:6470
- Definitive · G2P · X-linked · 2015
- Strong · Genomics England PanelApp · X-linked · 2021
- Supportive · Orphanet · X-linked · 2021
Where it sits
Other names
10 names
Resolves to: X-linked hydrocephalus with stenosis of the aqueduct of Sylvius
- Also called
- Bickers-Adams syndromeHSAShydrocephalus due to aqueductal stenosis, X-linked recessivehydrocephalus with congenital idiopathic intestinal pseudoobstruction, X-linked recessivehydrocephalus with hirschsprung disease, X-linked recessivehydrocephalus with stenosis of the aqueduct of SylviusX-linked acqueductal stenosisX-linked HSASX-linked hydrocephalusX-linked hydrocephalus with stenosis of aqueduct of Sylvius