Lissencephaly

Classification according to ICD-10
Q04.3	Other reduction deformities of the brain
ICD-10 online (WHO version 2019)

The lissencephaly in humans, a malformation of the brain . Be distinguished conceptually several versions: the complete absence of Gyrierung ( gyrus = Swirl, here: gyrus ) is agyria called reductions of convolutions, the term microgyria , enlargements, the term macrogyria summarized. The term pachygyria means reduced gyration with thickened / coarsened brain convolutions. If the convolutions of the brain are both reduced in size and increased in number, one speaks of polymicrogyria .

Lissencephaly is a very rare malformation. This is a congenital lack or a structural peculiarity of the cerebral convolutions ( gyri ) of the brain . The result of this disorder is a so-called smooth brain , which is noticeable through a relatively smooth (= lissos ) surface of the cerebral cortex ( cortex cerebri ).

The ICD-10 code for lissencephaly is Q04.3.

Classification

The group of diseases can be divided as follows:

Type I , classic lissencephaly , thickened four-layer cortex (10-20 mm, normal: 2.5-4 mm, six layers)

According to the genetic etiology, 4 forms are distinguished:

• Lissencephaly with mutations in the LIS1 gene , synonym: PAFAH1B1-associated lissencephaly
  • Isolated lissencephaly , synonym: Isolated lissencephaly sequence (ILS)
  • Miller-Dieker Syndrome
• Lissencephaly with mutations in the TUBA genes
• Lissencephaly with mutations in the DCX genes , synonym: Lissencephaly type 1, X-linked
• Lissencephaly with mutations in the ARX gene , synonym: X-linked lissencephaly with agenesis of the corpus callosum; XLAG syndrome
• Isolated lissencephaly with no known cause
• Lissencephaly with severe microcephaly , synonym: microlissencephaly
• Lissencephaly in the context of malformation syndromes
  • Norman Roberts Syndrome
  • Lissencephaly with cerebellar hypoplasia
  • Baraitser-Winter Syndrome
  • Craniotelencephalic dysplasia
  • Micro syndrome
  • Microlissencephaly-micromelia syndrome , synonym: Basel-Vanagaite-Sirota syndrome

Type II , synonym: cobblestone lissencephaly , irregular ('paved') surface, unlayered cortex

• • Walker-Warburg Syndrome
  • Fukuyama syndrome
  • Muscle eye brain disease

Type III

• • Lissencephaly type III - familial fetal akinesia / hypokinesia sequence
  • Lissencephaly type III - metacarpal bone dysplasia
  • Neu Laxova syndrome

Type IV microlissencephaly

diagnosis

The suspicion usually arises during an ultrasound scan while still in the womb or shortly after birth. A diagnosis can be confirmed by imaging by MRI .

Since the normal folding of the cerebral cortex does not take place until after the 24th week of pregnancy, a diagnosis of the absence of this gyration is also not possible beforehand.

Symptoms and ailments

The type and severity of the symptoms depend on the severity of the malformation , for example

• Malformations of internal organs
• Malformations of the brain
• Feeding disorders and problems swallowing
• Difficulty breathing, shortness of breath, and frequent pneumonia
• Spastic symptoms and cramps
• Epileptic seizures
• Visual impairment or hearing impairment
• Delay in physical and psychomotor development
• Severe intellectual disability , partly on a baby level
• Depending on the severity, lissencephaly can lead to the death of the child after a few months to years of life . In milder forms, reaching adulthood is possible.

causes

The malformation occurs in the first one to four months of the child's prenatal (= prenatal) development.

The cause is a migration disorder of cortical neurons . The malformation can be genetically predisposed, but it can also be caused by poisoning , viral infections or chromosome peculiarities or be partly due.

Consequences and complications

The malformation of the brain leads to severe intellectual disabilities and delays in psychomotor skills . The children partly remain at the stage of development of a baby , ie they cannot eat and drink independently. It follows that they usually have to be fed via a nasal tube or a percutaneous endoscopic gastrostomy (PEG). They cannot walk and speak, do not learn to hold their own heads, kick hardly or only very clumsily, and sometimes have very pronounced foreheads and large teeth. After a few months of life, the children begin to fist spastically.

In addition, there are pronounced physical symptoms such as visual and hearing impairments, swallowing disorders , breathing problems (with frequent pneumonia ) and epileptic syndromes .

Lissencephaly is often an anatomical abnormality in the context of syndromes ( Zellweger syndrome or Neu-Laxova syndrome ) or has other peculiarities: e.g. B. Microcephaly . The malformations in the brain have an epileptogenic effect, i. H. the risk of developing epilepsy (e.g. West syndrome / BNS epilepsy) is higher than average.

Fukuyama syndrome and Norman-Roberts syndrome are rare special forms of lissencephaly .

treatment

There is no causal treatment for lissencephaly. At most it is possible to treat the individual symptoms.

See also

• Baraitser-Winter Syndrome
• XLAG syndrome

Web links

• Clinic, genetics and pathogenesis of lissencephaly
• Genetics of lissencephaly: a neural migratory disorder
• Self-help association Liss eV

Individual evidence

1. ↑ Rare Diseases
2. ↑ Lissencephaly. In: Orphanet (Rare Disease Database).
3. ↑ Lissencephaly, classical. In: Orphanet (Rare Disease Database).
4. ↑ Lissencephaly due to LIS1 gene mutation. In: Orphanet (Rare Disease Database).
5. ^ Genetics Home Reference ILS
6. ↑ Lissencephaly due to TUBA1A gene mutation. In: Orphanet (Rare Disease Database).
7. ↑ Lissencephaly type 1 with doublecortin (DCX) gene mutation. In: Orphanet (Rare Disease Database).
8. ↑ X-linked lissencephaly with genital anomalies. In: Orphanet (Rare Disease Database).
9. ↑ Lissencephaly type 1, isolated, with no known genetic defect. In: Orphanet (Rare Disease Database).
10. ↑ Microlissencephaly. In: Orphanet (Rare Disease Database).
11. ↑ Lissencephaly with cerebellar hypoplasia. In: Orphanet (Rare Disease Database).
12. ↑ Baraitser-Winter Syndrome. In: Orphanet (Rare Disease Database).
13. ↑ Dysplasia, craniotelencephalic. In: Orphanet (Rare Disease Database).
14. ↑ Microlissencephaly - micromelia. In: Orphanet (Rare Disease Database).
15. ↑ Lissencephaly type 2. In: Orphanet (database for rare diseases).
16. ↑ Muscular dystrophy, congenital, Fukuyama type. In: Orphanet (Rare Disease Database).
17. ↑ Lissencephaly type 3. In: Orphanet (database for rare diseases).
18. ↑ Lissencephaly type III - familial fetal akinesia / hypokinesia sequence. In: Orphanet (Rare Disease Database).
19. ↑ Lissencephaly type III - metacarpal bone dysplasia. In: Orphanet (Rare Disease Database).
20. ↑ Microlissencephaly. In: Orphanet (Rare Disease Database).
21. ↑ Lissencephaly 4.  In: Online Mendelian Inheritance in Man . (English)
22. ^ V. Hofmann, KH Deeg, PF Hoyer: Ultrasound diagnostics in paediatrics and pediatric surgery. Textbook and atlas. Thieme, 2005, ISBN 3-13-100953-5 .

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !