Karyotype 46, X w abnormal sex chromosome, except iso (Xq)

This code describes a genetic condition characterized by a female karyotype (46, XX) where one of the X chromosomes has a structural abnormality, but it is not an isochromosome of the long arm (Xq). This typically results in a partial deletion or duplication of the X chromosome, leading to varying clinical presentations depending on the specific chromosomal segment involved.

Apply this code when documentation confirms a cytogenetic analysis revealing a 46,X karyotype with a structural abnormality of an X chromosome, explicitly excluding isochromosome Xq. This is often seen in patients presenting with features of Turner syndrome variants or other X-linked genetic disorders. Supporting documentation must include a detailed cytogenetic report.

• Ensure the cytogenetic report specifically states "except iso (Xq)" or provides details of the X chromosome abnormality that rule out isochromosome Xq.
• Do not use this code for classic Turner syndrome (45,X) or for isochromosome Xq, which have their own specific codes.
• Sequence this code as a primary diagnosis when the genetic anomaly is the reason for the encounter or the underlying cause of the patient's symptoms.