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Hypoplastic olfactory lobes

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Concept ID:
HPO: HP:0006894

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Conditions with this feature

Peroxisome biogenesis disorder 1A (Zellweger)
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Concept ID:
Disease or Syndrome
Zellweger spectrum disorder (ZSD) is a phenotypic continuum ranging from severe to mild. While individual phenotypes (e.g., Zellweger syndrome [ZS], neonatal adrenoleukodystrophy [NALD], and infantile Refsum disease [IRD]) were described in the past before the biochemical and molecular bases of this spectrum were fully determined, the term "ZSD" is now used to refer to all individuals with a defect in one of the ZSD-PEX genes regardless of phenotype. Individuals with ZSD usually come to clinical attention in the newborn period or later in childhood. Affected newborns are hypotonic and feed poorly. They have distinctive facies, congenital malformations (neuronal migration defects associated with neonatal-onset seizures, renal cysts, and bony stippling [chondrodysplasia punctata] of the patella[e] and the long bones), and liver disease that can be severe. Infants with severe ZSD are significantly impaired and typically die during the first year of life, usually having made no developmental progress. Individuals with intermediate/milder ZSD do not have congenital malformations, but rather progressive peroxisome dysfunction variably manifest as sensory loss (secondary to retinal dystrophy and sensorineural hearing loss), neurologic involvement (ataxia, polyneuropathy, and leukodystrophy), liver dysfunction, adrenal insufficiency, and renal oxalate stones. While hypotonia and developmental delays are typical, intellect can be normal. Some have osteopenia; almost all have ameleogenesis imperfecta in the secondary teeth.

Recent clinical studies


Benson JC, Nascene D, Truwit C, McKinney AM
Clin Neuroradiol 2019 Sep;29(3):505-513. Epub 2018 Apr 16 doi: 10.1007/s00062-018-0687-z. PMID: 29663010
Zhang Z, Sun X, Wang C, Wang G, Zhao B
J Comput Assist Tomogr 2016 Jan-Feb;40(1):39-42. doi: 10.1097/RCT.0000000000000334. PMID: 26571055


Zhang Z, Sun X, Wang C, Wang G, Zhao B
J Comput Assist Tomogr 2016 Jan-Feb;40(1):39-42. doi: 10.1097/RCT.0000000000000334. PMID: 26571055


Sarnat HB, Benjamin DR, Siebert JR, Kletter GB, Cheyette SR
Pediatr Dev Pathol 2002 Jan-Feb;5(1):54-68. doi: 10.1007/s10024-001-0103-5. PMID: 11815869

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