skip navigation links
National Cancer Institute
Enterprise Vocabulary Services
Box
NCIm Version: 201706 (Browser Version 2.9, using LexEVS 6.5.1)
SearchBox Top
SearchBox Bottom
Klinefelter Syndrome (CUI C0022735) Suggest changes to this concept
Add to Cart

Terms & Properties

Concept Unique Identifier (CUI): C0022735

NCI Thesaurus Code: C34752  (see NCI Thesaurus info)

Semantic Type: Disease or Syndrome

Semantic Type: Congenital Abnormality

NCIt Definition: A sex chromosome disorder caused by the presence of an extra X chromosome in the male karyotype. Affected individuals are infertile and have a small penis and testes. They tend to have tall stature and long legs and may have difficulties with speech and language development. Gynecomastia may be present.

GARD Definition: Klinefelter syndrome (KS) is a condition that may be present in an individual that has two X chromosomes and one Y chromosome (47, XXY); usually, males have one X and one Y (XY) and females have two X chromosomes (XX). Some individuals with a 47, XXY chromosome finding may have no obvious signs or symptoms of KS while others may have several features and varying degrees of cognitive, social, behavioral, and learning difficulties. Because features may not be apparent until mid to late adolescence, the term “Klinefelter syndrome” is often reserved for affected adolescents and adults. Although the vast majority of boys with KS identify as males, some individuals develop atypical gender identities. In adulthood, individuals with Klinefelter syndrome may have primary hypogonadism (decreased testosterone production), small testes, enlarged breast tissue (gynecomastia), tall stature, and/or other features. The vast majority of males with KS are infertile, but many produce sperm and may be able to conceive with assisted reproduction. Treatment varies among individuals and may include testosterone therapy; however, this therapy may not be appropriate for all individuals. - this information is from GARD/ORDR/NCATS.

SNOMEDCT_US Definition: A male with two or more X chromosomes.

MEDLINEPLUS Definition: 

Klinefelter syndrome (KS) is a condition that occurs in men who have an extra X chromosome. The syndrome can affect different stages of physical, language, and social development.

The most common symptom is infertility. Boys may be taller than other boys their age, with more fat around the belly. After puberty, KS boys may have

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

KS males may have learning or language problems. They may be quiet and shy and have trouble fitting in.

A genetic test can diagnose KS. There is no cure, but treatments are available. It is important to start treatment as early as possible. With treatment, most boys grow up to have normal lives.

Treatments include testosterone replacement therapy and breast reduction surgery. If needed, physical, speech, language, and occupational therapy may also help.

NIH: National Institute of Child Health and Human Development

NCI-GLOSS Definition: A genetic disorder in males caused by having one or more extra X chromosomes. Males with this disorder may have larger than normal breasts, a lack of facial and body hair, a rounded body type, and small testicles. They may learn to speak much later than other children and may have difficulty learning to read and write. Klinefelter syndrome increases the risk of developing extragonadal germ cell tumors and breast cancer.

NICHD Definition: A condition caused by the presence of an extra X chromosome resulting in 47,XXY karyotype in an individual with male phenotype. The condition is characterized in childhood by relative tall stature with disproportionately long limbs, and speech/language developmental problems in some patients. Postpubertal findings include small testes, gynecomastia, and infertility.

CSP Definition: genetic disease that produces sterile males with small testes lacking sperm due to XXY karyotype.

MSH Definition: 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.).

Synonyms & Abbreviations: (see Synonym Details)
47,XXY Syndrome
Hypogonadism, primary
Hypogonadotropic Hypogonadism
Klinefelter syndrome (disorder)
Klinefelter Syndrome [Disease/Finding]
Klinefelter syndrome karyotype 47, XXY
Klinefelter syndrome, male with more than two X chromosomes
Klinefelter syndrome, unspecified
Klinefelter syndrome, XXY
Klinefelter Syndromes
KLINEFELTER SYNDROME
Klinefelter's syndrome - male with more than two X chromosomes
Klinefelter's syndrome karyotype 47 XXY
Klinefelter's syndrome karyotype 47,XXY
Klinefelter's syndrome, male with more than two X chromosomes
Klinefelter's syndrome, unspecified
Klinefelter's syndrome, XXY (disorder)
Klinefelter's Syndrome, XXY
KLINEFELTER'S SYNDROME
Klinefelters Syndrome
Syndrome, Klinefelter's
Syndrome, Klinefelter
Syndrome, XXY
Syndromes, Klinefelter
Syndromes, XXY
XXY Klinefelter's syndrome
XXY male
XXY Syndrome (Klinefelter Syndrome)
XXY Syndromes
XXY SYNDROME
XXY trisomy

External Source Codes: 
NCI Thesaurus Code C34752 (see NCI Thesaurus info)

Other Properties: Property Definitions
Name Value Source
ACTIVE 1 SNOMEDCT_US
AN index here karyotypes XXXY, XXXXY, XXYY, XXXYY, XX/XXY, XX/YY, XY/XXY, XXY/XXXY, XXY/XXYY, XY/XXY/XXXY if called KLINEFELTER SYNDROME by author but if not so named by author, index under SEX CHROMOSOME DISORDERS MSH
AQL BL CF CI CL CO DG DH DI DT EC EH EM EN EP ET GE HI IM ME MI MO NU PA PC PP PS PX RH RT SU TH UR VE VI MSH
CASE_SIGNIFICANCE_ID 900000000000017005 SNOMEDCT_US
Contributing_Source NICHD NCI
CTV3ID PJ7.. SNOMEDCT_US
CTV3ID XUaP0 SNOMEDCT_US
DATE_CREATED 08/16/2001 MEDLINEPLUS
DATE_CREATED 2013-01-09T00:04:00 GARD
DATE_LAST_MODIFIED 2013-01-09T00:04:00 GARD
DC 1 MSH
DEFINITION_STATUS_ID 900000000000074008 SNOMEDCT_US
DID 1254-8437 CSP
DISEASE_IDENTIFIER_ID 3308 GARD
DISEASE_IDENTIFIER_ID 3310 GARD
DX 19660101 MSH
EFFECTIVE_TIME 20040131 SNOMEDCT_US
EFFECTIVE_TIME 20150731 SNOMEDCT_US
HAS_GARD_PAGE true GARD
IAN DEFAULT ICD10
ICE XXY syndrome ICD9CM
IDENTIFIER_TYPE_ID 1 GARD
IS_ACTIVE true GARD
IS_RARE true GARD
IS_SPANISH false GARD
LAST_REVIEW_ACTION Modified GARD
LAST_REVIEW_DATE 2013-09-16T00:00:00 GARD
MDA 19990101 MSH
MESH_DEFINITION 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.). NDFRT
MESH_DUI D007713 NDFRT
MESH_NAME Klinefelter Syndrome NDFRT
MESH_UI M0012062 NDFRT
MMR 20160628 MSH
MN C12.706.316.795.500 MSH
MN C13.351.875.253.795.500 MSH
MN C16.131.260.830.835.500 MSH
MN C16.131.939.316.795.500 MSH
MN C16.320.180.830.835.500 MSH
MN C19.391.119.795.500 MSH
MN C19.391.482.629 MSH
MP_HEALTH_TOPIC_URL https://www.nlm.nih.gov/medlineplus/klinefelterssyndrome.html MEDLINEPLUS
MP_OTHER_LANGUAGE_URL Spanish https://www.nlm.nih.gov/medlineplus/spanish/klinefelterssyndrome.html MEDLINEPLUS
MP_PRIMARY_INSTITUTE_URL National Institute of Child Health and Human Development http://www.nichd.nih.gov/ MEDLINEPLUS
NDFRT_KIND DISEASE_KIND NDFRT
NICHD_Hierarchy_Term Klinefelter Syndrome NCI
NUI N0000001759 NDFRT
ORDER_NO 28209 ICD10CM
ORDER_NO 28210 ICD10CM
ORDER_NO 28212 ICD10CM
PRIMARY_PATH 10023463$10040453$10008804$10010331$Klinefelter's syndrome$Sex chromosomal abnormalities$Chromosomal abnormalities and abnormal gene carriers$Congenital, familial and genetic disorders MDR
PRIMARY_SOC 10010331 MDR
PT_IN_VERSION 10.0 MDR
PT_IN_VERSION 10.1 MDR
PT_IN_VERSION 11.0 MDR
PT_IN_VERSION 11.1 MDR
PT_IN_VERSION 12.0 MDR
PT_IN_VERSION 12.1 MDR
PT_IN_VERSION 13.0 MDR
PT_IN_VERSION 13.1 MDR
PT_IN_VERSION 14.0 MDR
PT_IN_VERSION 14.1 MDR
PT_IN_VERSION 15.0 MDR
PT_IN_VERSION 15.1 MDR
PT_IN_VERSION 16.0 MDR
PT_IN_VERSION 16.1 MDR
PT_IN_VERSION 17.0 MDR
PT_IN_VERSION 17.1 MDR
PT_IN_VERSION 18.0 MDR
PT_IN_VERSION 18.1 MDR
PT_IN_VERSION 19.0 MDR
PT_IN_VERSION 19.1 MDR
PT_IN_VERSION 8.0 MDR
PT_IN_VERSION 8.1 MDR
PT_IN_VERSION 9.0 MDR
PT_IN_VERSION 9.1 MDR
RARE_DISEASE_URL http://rarediseases.info.nih.gov/gard/8705/klinefelter-syndrome/resources/1 GARD
RXAUI 3184948 RXNORM
RXAUI 3184949 RXNORM
RXAUI 3184951 RXNORM
RXAUI 4224058 RXNORM
RXCUI 1023413 RXNORM
SMQ_TERM_ADDVERSION 10.0 MDR
SMQ_TERM_CAT A MDR
SMQ_TERM_LEVEL 4 MDR
SMQ_TERM_LEVEL 5 MDR
SMQ_TERM_LMVERSION 14.0 MDR
SMQ_TERM_SCOPE 2 MDR
SMQ_TERM_STATUS A MDR
SMQ_TERM_WEIGHT 0 MDR
SNOMED_CID 405769009 NDFRT
SNOMEDID D4-02252 SNOMEDCT_US
SNOMEDID D4-02289 SNOMEDCT_US
SUBSET_MEMBER 447562003~CORRELATIONID~447561005 SNOMEDCT_US
SUBSET_MEMBER 447562003~MAPADVICE~ALWAYS Q98.1 SNOMEDCT_US
SUBSET_MEMBER 447562003~MAPADVICE~ALWAYS Q98.4 SNOMEDCT_US
SUBSET_MEMBER 447562003~MAPCATEGORYID~447637006 SNOMEDCT_US
SUBSET_MEMBER 447562003~MAPGROUP~1 SNOMEDCT_US
SUBSET_MEMBER 447562003~MAPPRIORITY~1 SNOMEDCT_US
SUBSET_MEMBER 447562003~MAPRULE~TRUE SNOMEDCT_US
SUBSET_MEMBER 447562003~MAPTARGET~Q98.1 SNOMEDCT_US
SUBSET_MEMBER 447562003~MAPTARGET~Q98.4 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~CORRELATIONID~447561005 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPADVICE~ALWAYS Q98.0 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPADVICE~ALWAYS Q98.4 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPADVICE~IF KLINEFELTER'S SYNDROME XXXXY CHOOSE Q98.1 | MAP OF SOURCE CONCEPT IS CONTEXT DEPENDENT SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPADVICE~IF KLINEFELTER'S SYNDROME XXXY CHOOSE Q98.1 | MAP OF SOURCE CONCEPT IS CONTEXT DEPENDENT SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPADVICE~IF KLINEFELTER'S SYNDROME, XXY CHOOSE Q98.0 | MAP OF SOURCE CONCEPT IS CONTEXT DEPENDENT SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPADVICE~IF KLINEFELTER'S SYNDROME, XXYY CHOOSE Q98.1 | MAP OF SOURCE CONCEPT IS CONTEXT DEPENDENT SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPADVICE~IF KLINEFELTER'S SYNDROME, XY/XXY MOSAIC CHOOSE Q98.1 | MAP OF SOURCE CONCEPT IS CONTEXT DEPENDENT SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPCATEGORYID~447637006 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPCATEGORYID~447639009 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPGROUP~1 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPPRIORITY~1 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPPRIORITY~2 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPPRIORITY~3 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPPRIORITY~4 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPPRIORITY~5 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPPRIORITY~6 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPRULE~IFA 205699007 | Klinefelter's syndrome, XXYY (disorder) | SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPRULE~IFA 205700008 | Klinefelter's syndrome, XY/XXY mosaic (disorder) | SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPRULE~IFA 275263003 | Klinefelter's syndrome XXXY (disorder) | SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPRULE~IFA 275264009 | Klinefelter's syndrome XXXXY (disorder) | SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPRULE~IFA 405769009 | Klinefelter's syndrome, XXY (disorder) | SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPRULE~OTHERWISE TRUE SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPRULE~TRUE SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPTARGET~Q98.0 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPTARGET~Q98.1 SNOMEDCT_US
SUBSET_MEMBER 6011000124106~MAPTARGET~Q98.4 SNOMEDCT_US
SUBSET_MEMBER 900000000000497000~MAPTARGET~PJ7.. SNOMEDCT_US
SUBSET_MEMBER 900000000000497000~MAPTARGET~XUaP0 SNOMEDCT_US
SUBSET_MEMBER 900000000000498005~MAPTARGET~D4-02252 SNOMEDCT_US
SUBSET_MEMBER 900000000000498005~MAPTARGET~D4-02289 SNOMEDCT_US
SUBSET_MEMBER 900000000000508004~ACCEPTABILITYID~900000000000548007 SNOMEDCT_US
SUBSET_MEMBER 900000000000508004~ACCEPTABILITYID~900000000000549004 SNOMEDCT_US
SUBSET_MEMBER 900000000000509007~ACCEPTABILITYID~900000000000548007 SNOMEDCT_US
SUBSET_MEMBER 900000000000509007~ACCEPTABILITYID~900000000000549004 SNOMEDCT_US
TERMUI T023149 MSH
TERMUI T432071 MSH
TERMUI T782689 MSH
TH GHR (2014) MSH
TH NLM (1966) MSH
TH NLM (2002) MSH
TH NLM (2012) MSH
TH ORD (2010) MSH
TYPE_ID 900000000000003001 SNOMEDCT_US
TYPE_ID 900000000000013009 SNOMEDCT_US

Additional Concept Data:  (none)

URL to Bookmark: https://ncim-stage.nci.nih.gov/ncimbrowser/ConceptReport.jsp?dictionary=NCI Metathesaurus&code=C0022735

Mainbox Bottom