ICD10 code of Koolen De Vries Syndrome / 17q21.31 Microdeletion Syndrome and ICD9 code

Koolen-de Vries syndrome (also known as 17q21.31 microdeletion syndrome) does not have a unique, dedicated ICD-10 or ICD-9 code. Clinicians typically use the generic code Q93.5 (Other deletions of part of a chromosome) under ICD-10 or 758.39 (Other deletions of autosomes) under ICD-9 for billing and medical record purposes.

Why does Koolen-de Vries syndrome lack a specific ICD code?

Because Koolen-de Vries syndrome is a rare genetic condition caused by a microdeletion on chromosome 17, it falls under the broader category of chromosomal anomalies. In medical coding, specific rare diseases often lack individual codes unless they have a high enough prevalence to warrant a unique entry in the International Classification of Diseases. For Koolen-de Vries syndrome, medical professionals rely on descriptive codes that reflect the underlying chromosomal mechanism.

How is a diagnosis of Koolen-de Vries syndrome confirmed?

Diagnosis is confirmed through specialized genetic testing rather than clinical observation alone. If your physician suspects Koolen-de Vries syndrome, they will likely order a Chromosomal Microarray (CMA) or a targeted FISH test to identify the deletion at the 17q21.31 locus. Current clinical data suggests the syndrome occurs in approximately 1 in 16,000 to 1 in 55,000 live births, though many cases may remain undiagnosed.

What are the primary clinical features of the syndrome?

The clinical presentation of Koolen-de Vries syndrome is highly variable, but common features often include:

• Developmental delays, particularly in speech and language acquisition.


• Characteristic facial features, such as a prominent forehead and "pear-shaped" face.


• Mild to moderate intellectual disability.


• Congenital heart defects or renal anomalies in some individuals.


• A friendly, sociable, and cooperative personality profile.

Is Koolen-de Vries syndrome hereditary?

In the vast majority of cases, Koolen-de Vries syndrome occurs de novo, meaning it is a sporadic genetic event that happens during the formation of reproductive cells or early embryonic development. It is rarely inherited from a parent, though a clinical geneticist should perform a parental blood test to confirm the origin of the 17q21.31 deletion.

Next steps

• Consult with a clinical geneticist to review your family’s specific genetic test results.


• Connect with the 8 members on DiseaseMaps.org who share lived experiences with Koolen-de Vries syndrome.


• Register with the Koolen-de Vries Syndrome Foundation for access to specialized research and community resources.

Medical disclaimer: This information is for educational purposes only and does not constitute medical advice, diagnosis, or treatment; always seek the advice of your physician or qualified health provider with any questions regarding a medical condition.

References

• NIH Genetic and Rare Diseases Information Center (GARD): 17q21.31 microdeletion syndrome.


• Orphanet: Koolen-de Vries syndrome (ORPHA: 171638).


• OMIM (Online Mendelian Inheritance in Man): #610443.


• Koolen-de Vries Syndrome Foundation (kdvsfoundation.org).