Other sex chromosome abnormalities, male phenotype, not elsewhere classified (Q98) ICD-10-CM
The Q98 code range covers other sex chromosome abnormalities, male phenotype, not elsewhere classified with 10 ICD-10-CM diagnosis codes. 9 of them are billable and valid for claim submission in fiscal year 2027, and the category headers group them but cannot themselves be billed.
Codes in the Q98 Range 10 codes · 9 billable
- Q98 Other sex chromosome abnormalities, male phenotype, not elsewhere classifiedNon-billable
- Q98.0 Klinefelter syndrome karyotype 47, XXY
- Q98.1 Klinefelter syndrome, male with more than two X chromosomes
- Q98.3 Other male with 46, XX karyotype
- Q98.4 Klinefelter syndrome, unspecified
- Q98.5 Karyotype 47, XYY
- Q98.6 Male with structurally abnormal sex chromosome
- Q98.7 Male with sex chromosome mosaicism
- Q98.8 Other specified sex chromosome abnormalities, male phenotype
- Q98.9 Sex chromosome abnormality, male phenotype, unspecified
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the Q98 range.
Klinefelter Syndrome
A form of male HYPOGONADISM, characterized by the presence of an extra X CHROMOSOME, small TESTES, seminiferous tubule dysgenesis, elevated levels of GONADOTROPINS, low serum TESTOSTERONE, underdeveloped secondary sex characteristics, and male infertility (INFERTILITY, MALE). Patients tend to have long legs and a slim, tall stature. GYNECOMASTIA is present in many of the patients. The classic form has the karyotype 47,XXY. Several karyotype variants include 48,XXYY; 48,XXXY; 49,XXXXY, and mosaic patterns ( 46,XY/47,XXY; 47,XXY/48,XXXY, etc.).
Sex Chromosome Aberrations
Abnormal number or structure of the SEX CHROMOSOMES. Some sex chromosome aberrations are associated with SEX CHROMOSOME DISORDERS and SEX CHROMOSOME DISORDERS OF SEX DEVELOPMENT.
About the Q98 Code Range
These abnormalities involve sex chromosomes in people with a male phenotype, meaning male physical traits.
Klinefelter syndrome has separate codes for a 47, XXY chromosome pattern (Q98.0), more than two X chromosomes (Q98.1), and an unspecified pattern (Q98.4). Other codes distinguish a male with a 46, XX pattern (Q98.3), a 47, XYY pattern (Q98.5), a structurally abnormal sex chromosome (Q98.6), and sex chromosome mosaicism (Q98.7). Separate codes identify other specified abnormalities (Q98.8) and an unspecified abnormality (Q98.9).
Questions About This Page
How many billable codes are in the Q98 range?
Of the 10 codes in this range, 9 are billable and valid for claim submission from October 1, 2026 through September 30, 2027. Category header codes group them but cannot be reported on claims.
What does the Q98 range classify?
The range classifies other sex chromosome abnormalities, male phenotype, not elsewhere classified. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2027 ICD-10-CM Tabular List and order file, effective October 1, 2026 through September 30, 2027.
