ICD10 code of Miller-Dieker syndrome and ICD9 code

Miller-Dieker syndrome is classified under the ICD-10 code Q93.5 (Other deletions of part of a chromosome) and the ICD-9 code 758.3 (Deletions of autosomes). These codes reflect that Miller-Dieker syndrome is caused by a contiguous gene deletion on chromosome 17p13.3, which results in characteristic neurological and physical features.

What is the clinical significance of Miller-Dieker syndrome?

Miller-Dieker syndrome is a rare, severe genetic disorder primarily characterized by lissencephaly (a "smooth brain" appearance due to the absence of normal folds and grooves) and distinct facial features. Because Miller-Dieker syndrome involves the deletion of multiple genes, including the PAFAH1B1 (formerly LIS1) gene, patients typically experience profound developmental delays, intellectual disability, and recurring seizures. At DiseaseMaps.org, 19 individuals have joined our community to share their experiences with this condition, highlighting the importance of specialized neurological and supportive care for families navigating this diagnosis.

How is the diagnosis of Miller-Dieker syndrome confirmed?

Diagnosis is usually confirmed through genetic testing rather than clinical observation alone. Because Miller-Dieker syndrome is a microdeletion syndrome, standard karyotyping may miss the deletion if it is very small. Clinical geneticists prefer chromosomal microarray (CMA) or fluorescence in situ hybridization (FISH) to identify the specific deletion at 17p13.3. When a child presents with severe hypotonia, feeding difficulties, and the classic facial features—such as a prominent forehead, bitemporal narrowing, and a thin upper lip—a geneticist will order these tests to confirm Miller-Dieker syndrome.

Is Miller-Dieker syndrome hereditary?

In the vast majority of cases, Miller-Dieker syndrome occurs as a de novo (new) mutation in the affected individual, meaning it is not inherited from either parent. However, in approximately 20% of cases, one parent may carry a balanced chromosomal translocation involving the 17p13.3 region. While the parent is typically healthy, they are at an increased risk of having subsequent children with Miller-Dieker syndrome. Genetic counseling is essential for all families to determine the recurrence risk through parental karyotype testing.

What are the primary clinical features of Miller-Dieker syndrome?

The clinical presentation of Miller-Dieker syndrome is multi-systemic. While every child is unique, common features include:

• Lissencephaly: Grade 1 (agyria), which leads to severe neurological impairment.


• Seizure disorders: Often difficult to manage and beginning in infancy.


• Craniofacial anomalies: Including a high, prominent forehead, downward-slanting palpebral fissures, and a small nose with upturned nostrils.


• Feeding and Growth: Significant failure to thrive and severe feeding difficulties requiring specialized nutrition or G-tube support.


• Developmental delay: Global developmental delay with limited speech and motor skill acquisition.

Next steps

• Consult a clinical geneticist to discuss chromosomal microarray testing and parental carrier studies.


• Coordinate care with a pediatric neurologist to manage seizure activity and neurodevelopmental support.


• Engage with early intervention programs, including physical, occupational, and speech therapy, to maximize the quality of life for your child.


• Connect with the 19 members of the DiseaseMaps.org community to share experiences and find emotional support from families familiar with the challenges of Miller-Dieker syndrome.

Medical disclaimer: This information is for educational purposes only and does not replace professional medical advice, diagnosis, or treatment; always consult with your physician regarding your specific medical condition.

References

• NIH Genetic and Rare Diseases Information Center (GARD): Miller-Dieker syndrome overview.


• Orphanet: Rare disease database entry for Miller-Dieker syndrome (ORPHA:589).


• OMIM (Online Mendelian Inheritance in Man): Miller-Dieker Syndrome (#247200).


• The Lissencephaly Foundation: Support and resources for families affected by lissencephaly and Miller-Dieker syndrome.