Chromosome replaced with ring, dicentric or isochromosome

This code identifies a specific type of chromosomal abnormality where a chromosome has an altered structure, such as forming a ring, having two centromeres (dicentric), or being composed of two identical arms (isochromosome). These structural rearrangements can lead to various genetic disorders and developmental anomalies depending on the specific chromosome involved and the genes affected.

Apply this code when documentation from genetic testing or cytogenetic analysis confirms the presence of a ring chromosome, a dicentric chromosome, or an isochromosome. This diagnosis is typically made following karyotyping or other molecular genetic studies performed due to suspected genetic syndromes, developmental delays, or recurrent miscarriages.

• Always confirm the specific type of chromosomal rearrangement (ring, dicentric, or isochromosome) is explicitly documented.
• Do not use this code for other types of chromosomal abnormalities like translocations, deletions, or duplications; use more specific codes for those conditions.
• Sequence this code as a primary diagnosis when it is the reason for the encounter or as a secondary diagnosis when it contributes to the patient's overall clinical picture.