Start New EnglishEspañol中文РусскийالعربيةTiếng ViệtFrançaisDeutsch한국어Tagalog Library Performance
BETA v.3.0

2025 ICD-10-CM code Q98.9

Sex chromosome abnormality, male phenotype, unspecified.

Code Q98.9 should only be used when the specific type of sex chromosome abnormality cannot be determined.Once the specific condition is identified (e.g., Klinefelter syndrome, Turner syndrome variants affecting males), the appropriate more specific code should replace Q98.9.

The medical necessity for coding Q98.9 is established when a male phenotype is present, but there is insufficient information to specify the exact sex chromosome abnormality. This often arises from initial genetic testing, which indicates an anomaly, but further evaluation is needed for precise classification. The code helps for tracking and monitoring patients with suspected sex chromosome disorders.

A geneticist or medical geneticist is typically responsible for diagnosing and managing sex chromosome abnormalities.Other specialists such as endocrinologists and reproductive endocrinologists may be involved depending on the presentation and associated conditions.

IMPORTANT:ICD-9-CM code 758.81 (Other conditions due to sex chromosome anomalies) may be used for historical cross-referencing, but Q98.9 is the current, preferred code.

In simple words: This code describes a condition where a person is born with an unusual number or structure of their sex chromosomes, resulting in a male appearance, but the exact nature of the chromosome problem is unknown.Further testing is needed to determine the specific genetic abnormality.

This ICD-10-CM code classifies a sex chromosome abnormality presenting with a male phenotype where the specific type of abnormality is not specified.It encompasses various genetic conditions affecting the sex chromosomes (X and Y), resulting in a male outward appearance despite variations in the typical XY chromosomal makeup.The diagnosis necessitates comprehensive genetic testing to determine the precise chromosomal anomaly.

Example 1: A newborn male infant presents with ambiguous genitalia and delayed puberty. Karyotyping reveals a sex chromosome abnormality consistent with Klinefelter syndrome (XXY), but the exact variant is unclear.Code Q98.9 is used to reflect the uncertainty in the specific chromosomal abnormality while accounting for the male phenotype., A male patient presents with infertility and gynecomastia (breast enlargement).Genetic testing reveals a complex sex chromosome anomaly involving a mosaic pattern (e.g., a mixture of XY and XXY cells), but the precise nature of the mosaicism is undefined. Q98.9 is applied given the male phenotype and lack of precise determination., A male child exhibits developmental delays and learning difficulties. Initial genetic testing detects a sex chromosome anomaly, but more advanced molecular analysis is required to fully characterize the abnormality. The physician uses Q98.9 as a temporary code, pending results of further testing.

Detailed family history, physical examination findings noting any ambiguous genitalia or secondary sexual characteristic abnormalities, karyotype results (if available), and reports from any additional genetic testing should be included in the medical record to support the use of Q98.9.If the specific chromosomal anomaly is later identified, the code should be changed to reflect that specificity.

** This code is not for use on maternal records.It should be used only to classify sex chromosome abnormalities in individuals with a male phenotype.

** Only Enterprise users with EHR integration can access case-specific answers. Click here to request access.

Discover what matters.

iFrame™ AI's knowledge is aligned with and limited to the materials uploaded by users and should not be interpreted as medical, legal, or any other form of advice by iFrame™.