When is ICD-10 code Q98 used?

Doctors, hospitals, and insurers may use ICD-10 code Q98 when recording other sex chromosome abnormalities, male phenotype, not elsewhere classified in a standardized format. This entry may also act as a broader category that points toward more specific child codes.

Does ICD-10 code Q98 confirm a diagnosis?

No. A code helps standardize documentation and claims, but it should not be read as a substitute for a clinician's full assessment.

ICD10

ICD-10 Code Q98: Other sex chromosome abnormalities, male phenotype, not elsewhere classified

Name: ICD-10 Code Q98: Other sex chromosome abnormalities, male phenotype, not elsewhere classified
Creator: HealthAssure Clinical Team
Published: 2026-05-21T06:30:14.674Z

Q98 is an ICD-10 diagnosis entry used to group records related to Other sex chromosome abnormalities, male phenotype, not elsewhere classified. You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen. ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders (Q00-QA0).

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders (Q00-QA0).

When is it used?

May be used when a clinician documents other sex chromosome abnormalities, male phenotype, not elsewhere classified in a patient's medical record.
May appear in hospital records, claims, referrals, and clinical documentation.
This code may act more like a grouping or parent code, so a more specific child code may be used in final documentation when available.

What it does not mean

A code alone does not explain severity, treatment plan, or outcome.
A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
This entry may represent a broader category rather than the most specific billable code.

Code hierarchy

chapter

17Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders (Q00-QA0)

block

Q90-Q99Chromosomal abnormalities, not elsewhere classified

currentQ90-Q99

Where you may see this code

You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen.

Sibling codes

Q90Down syndrome Q91Trisomy 18 and Trisomy 13 Q92Other trisomies and partial trisomies of the autosomes, not elsewhere classified Q93Monosomies and deletions from the autosomes, not elsewhere classified Q95Balanced rearrangements and structural markers, not elsewhere classified Q96Turner's syndrome Q97Other sex chromosome abnormalities, female phenotype, not elsewhere classified Q99Other chromosome abnormalities, not elsewhere classified

Coding guidelines

Compatibility

Legacy code aligns to an official FY 2026 category. Frontend should resolve to the official category page and surface the billable child codes.

Legacy codes

Q98

Replacement codes

Q98.0 — Klinefelter syndrome karyotype 47, XXYQ98.1 — Klinefelter syndrome, male with more than two X chromosomesQ98.3 — Other male with 46, XX karyotypeQ98.4 — Klinefelter syndrome, unspecifiedQ98.5 — Karyotype 47, XYYQ98.6 — Male with structurally abnormal sex chromosomeQ98.7 — Male with sex chromosome mosaicismQ98.8 — Other specified sex chromosome abnormalities, male phenotypeQ98.9 — Sex chromosome abnormality, male phenotype, unspecified

Common synonyms

Other sex chromosome abnormalities, male phenotype, not elsewhere classified

Frequently asked questions

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.