2024 ICD-10-CM Diagnosis Code Q98.4

Klinefelter syndrome, unspecified

ICD-10-CM Code:
ICD-10 Code for:
Klinefelter syndrome, unspecified
Is Billable?
Yes - Valid for Submission
Chronic Condition Indicator: [1]
Code Navigator:

Code Classification

  • Congenital malformations, deformations and chromosomal abnormalities
    • Chromosomal abnormalities, not elsewhere classified
      • Other sex chromosome abnormalities, male phenotype, not elsewhere classified

Q98.4 is a billable diagnosis code used to specify a medical diagnosis of klinefelter syndrome, unspecified. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2023 through September 30, 2024. The code is exempt from present on admission (POA) reporting for inpatient admissions to general acute care hospitals.

This code is applicable to male patients only. It is clinically and virtually impossible to use this code on a non-male patient.

Unspecified diagnosis codes like Q98.4 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

  • Klinefelter syndrome

Clinical Classification

Clinical Information

  • 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.).

Index to Diseases and Injuries References

The following annotation back-references for this diagnosis code are found in the injuries and diseases index. The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10-CM code(s).

Code Edits

The Medicare Code Editor (MCE) detects and reports errors in the coding of claims data. The following ICD-10-CM Code Edits are applicable to this code:

  • Diagnoses for males only - The Medicare Code Editor detects inconsistencies between a patient’s sex and any diagnosis on the patient’s record, these edits apply to MALES only .

Present on Admission (POA)

Q98.4 is exempt from POA reporting - The Present on Admission (POA) indicator is used for diagnosis codes included in claims involving inpatient admissions to general acute care hospitals. POA indicators must be reported to CMS on each claim to facilitate the grouping of diagnoses codes into the proper Diagnostic Related Groups (DRG). CMS publishes a listing of specific diagnosis codes that are exempt from the POA reporting requirement. Review other POA exempt codes here.

CMS POA Indicator Options and Definitions

POA IndicatorReason for CodeCMS will pay the CC/MCC DRG?
YDiagnosis was present at time of inpatient admission.YES
NDiagnosis was not present at time of inpatient admission.NO
UDocumentation insufficient to determine if the condition was present at the time of inpatient admission.NO
WClinically undetermined - unable to clinically determine whether the condition was present at the time of inpatient admission.YES
1Unreported/Not used - Exempt from POA reporting. NO

Convert Q98.4 to ICD-9-CM

  • ICD-9-CM Code: 758.7 - Klinefelter's syndrome
    Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.

Patient Education

Klinefelter Syndrome

What is Klinefelter syndrome (KS)?

Klinefelter syndrome (KS) is a genetic condition that happens when a male is born with an extra copy of the X chromosome. KS can affect different stages of physical, language, and social development. It also usually causes infertility.

What causes Klinefelter syndrome (KS)?

KS is not inherited. It's caused by a random error that happens when a sperm or egg is formed. This error causes a male to be born with an extra X chromosome.

Chromosomes are tiny "packages" in your cells that contain your genes. Genes carry information, called DNA, that controls what you look like and how your body works. Normally, you're born with a set of 46 chromosomes in each cell, two of which are the sex chromosomes. Females usually have two X chromosomes (XX), and males usually have one X and one Y (XY). In KS, the male usually has two X chromosomes and one Y (XXY).

In rare cases, a male could have XY in some cells and XXY in other cells. This is called mosaic Klinefelter syndrome. Males with mosaic Klinefelter syndrome may have fewer symptoms, depending on the number of XY cells they have in their bodies and where those cells are located.

What are the symptoms of Klinefelter syndrome (KS)?

Some males with KS may have no symptoms or very mild symptoms. So they might not know that they have KS, or they might not get diagnosed with it right away. In other cases, the symptoms can be more severe.

Boys with KS may be taller than other boys their age, with more fat around the belly. After puberty, they may have:

  • Smaller testes and penis
  • Breast growth (called gynecomastia)
  • Less facial and body hair
  • Reduced muscle tone
  • Narrower shoulders and wider hips
  • Weaker bones
  • Decreased sexual interest
  • Lower energy

Many of these symptoms happen because of low testosterone in the body. Testosterone is the main male sex hormone.

Boys with KS may also have learning or language problems. These problems may affect them socially, so they may be shy and quiet and can have trouble fitting in.

Most males with KS are infertile because they make little or no sperm.

How is Klinefelter syndrome (KS) diagnosed?

A genetic test called a karyotype test can diagnose KS. This test can show if there are abnormal chromosomes, including if there is an extra X chromosome.

What are the treatments for Klinefelter syndrome (KS)?

There is no cure for KS, but treatments are available. The sooner the treatment is started, the better. If treatment is started by early puberty, it will likely help in reducing the symptoms.

Treatments for KS may include:

  • Testosterone replacement therapy
  • Surgery to remove or reduce breasts
  • Physical, speech, behavioral, and occupational therapy

In some cases, fertility treatments may help men with KS father children.

NIH: National Institute of Child Health and Human Development

[Learn More in MedlinePlus]

Klinefelter syndrome

Klinefelter syndrome, also called 47,XXY, is a chromosomal condition that affects development in people who are assigned male at birth. The signs and symptoms of Klinefelter syndrome vary. In some cases, the features are so mild that the condition is not diagnosed until puberty or adulthood. Researchers believe that up to 65 percent of people with Klinefelter syndrome are never diagnosed.

Individuals with Klinefelter syndrome typically have small testes that produce a reduced amount of testosterone (primary testicular insufficiency). Testosterone is the hormone that directs male sexual development before birth and during puberty. A small percentage of affected individuals are born with undescended testes (cryptorchidism). Without treatment, the shortage of testosterone can lead to delayed or incomplete puberty, breast enlargement (gynecomastia), decreased muscle mass, decreased bone density, a reduced amount of facial and body hair, and fatigue. Klinefelter syndrome can make it difficult for people with this condition to have biological children (a condition called infertility), but up to half of people with Klinefelter syndrome may be able to have children using assisted reproductive technologies.. 

The other physical changes associated with Klinefelter syndrome are usually subtle. Most commonly, affected individuals are taller than average and 2 to 3 inches taller than would be expected for their family. Other features can include curved pinky fingers (fifth finger clinodactyly), flat feet (pes planus), and, less commonly, abnormal fusion of certain bones in the forearm (radioulnar synostosis).

Children with Klinefelter syndrome may have low muscle tone (hypotonia), difficulty coordinating movements, and mild delays of certain developmental skills, such as rolling over or walking. Affected children have an increased risk of mild delays in speech and language development. People with Klinefelter syndrome tend to have better receptive language skills (the ability to understand speech) than expressive language skills (vocabulary and the production of speech) and may have difficulty communicating and expressing themselves. Affected individuals have an increased risk for learning disabilities, most commonly problems with reading (dyslexia) and written expression. People with Klinefelter syndrome very rarely have intellectual disabilities. 

Individuals with Klinefelter syndrome may have have anxiety, depression,  impaired social skills, or behavioral differences, such as emotional immaturity during childhood or difficulty with frustration. Affected individuals also have an increased risk for attention-deficit/hyperactivity disorder (ADHD), though they tend to have problems with attention and distractability rather than hyperactivity. People with Klinefelter syndrome are more likely than those without Klinefelter syndrome to have autism spectrum disorder, which is a developmental disorder that affects communication and social interaction.

People with Klinefelter syndrome have an increased risk of developing metabolic syndrome, which is a group of conditions that include high blood glucose levels during prolonged periods without food (fasting), high blood pressure (hypertension), increased belly fat, and high levels of fats (lipids) such as cholesterol and triglycerides in the blood. Compared with unaffected people, adults with Klinefelter syndrome also have an increased risk of developing involuntary trembling (tremors) in their arms or hands, breast cancer (if gynecomastia develops), thinning and weakening of the bones (osteoporosis), and autoimmune disorders such as systemic lupus erythematosus and rheumatoid arthritis. Autoimmune disorders are a large group of conditions that occur when the immune system attacks the body's own tissues and organs.

[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.


[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.