Q98.1 ICD-10-CM Code: Klinefelter syndrome, male with more than two X chromosomes
Q98.1 is the billable ICD-10-CM code for “Klinefelter syndrome, male with more than two X chromosomes” in the FY 2027 U.S. code set, effective Oct 1, 2026.
Official description
Q98.1Klinefelter syndrome, male with more than two X chromosomes
ICD-10-CM diagnosis code · United States clinical modification
Where Q98.1 sits
- 1
Chapter 17
Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders (Q00-QA1)
- 2
Section
Chromosomal abnormalities, not elsewhere classified (Q90-Q99)
- 3
Category Q98
Other sex chromosome abnormalities, male phenotype, not elsewhere classified
- 4
Code Q98.1
Klinefelter syndrome, male with more than two X chromosomes
Notes for this code
Inclusion terms
No inclusion terms are listed for Q98.1.
Code first
No “code first” instruction is listed for Q98.1.
Use additional code
No “use additional code” instruction is listed for Q98.1.
Excludes1
Conditions that should not be reported together with this code.
No Excludes1 note is listed for Q98.1.
Excludes2
Conditions not included here that may be reported separately when present.
No Excludes2 note is listed for Q98.1.
Source and release
- Data release
- U.S. ICD-10-CM · FY 2027
- Effective date
- Oct 1, 2026
- Publisher
- Vero Scribe Inc.
This reference is generated from Vero’s ICD-10-CM description, hierarchy, and code-note dataset. The visible content and structured data share that source.
Frequently asked questions
What does ICD-10-CM code Q98.1 mean?
Q98.1 is the FY 2027 U.S. ICD-10-CM code for “Klinefelter syndrome, male with more than two X chromosomes.”
Is Q98.1 a billable or specific ICD-10-CM code?
Yes. In the FY 2027 reference data used on this page, Q98.1 has no child codes and is presented as a billable/specific code. Always confirm the active code set and payer requirements before use.
Where is Q98.1 located in ICD-10-CM?
Q98.1 is listed in Chapter 17, Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders (Q00-QA1), within Chromosomal abnormalities, not elsewhere classified (Q90-Q99) (Q90–Q99), under category Q98, Other sex chromosome abnormalities, male phenotype, not elsewhere classified.
What coding notes are listed for Q98.1?
No inclusion terms are listed for Q98.1 in this reference record. No code-first instruction is listed. No Excludes1 note is listed. No Excludes2 note is listed.