Chromosomal abnormalities, not elsewhere classified (Q90-Q99)
ICD-10 codes Q90-Q99 cover a diverse set of chromosomal abnormalities not elsewhere classified, including well-known conditions like Down syndrome (Q90), Turner’s syndrome (Q96), and Klinefelter syndrome (Q98.0). These codes specifically categorize various trisomies, monosomies, partial deletions, duplications, balanced rearrangements, and sex chromosome anomalies, making them essential for precise diagnosis and documentation of genetic disorders.
This range includes distinct subtypes such as nonmosaic and mosaic forms of trisomy 21, 18, and 13, often referred to by synonyms like Trisomy 21- meiotic nondisjunction (Q90.0) and Down syndrome. Codes like Q92 describe other autosomal trisomies or partial trisomies with extensive synonyms listing specific partial duplications. The Q93 series addresses monosomies and deletions with famous examples like Wolf Hirschhorn syndrome (Q93.3) and Cri du chat syndrome (Q93.4). Balanced translocations and marker chromosomes have specific codes (Q95). Sex chromosome abnormalities, such as Turner syndrome (Q96), Triple X syndrome (Q97.0), and male karyotype anomalies including Klinefelter syndrome (Q98), are detailed with variants and mosaics. The final block Q99 covers other chromosomal anomalies including Fragile X syndrome (Q99.2) and unspecified chromosomal abnormalities, supporting nuanced genetic coding for diverse clinical scenarios.
Congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
Chromosomal abnormalities, not elsewhere classified (Q90-Q99)
Q91 Trisomy 18 and Trisomy 13
- Q91.0 Trisomy 18, nonmosaicism (meiotic nondisjunction)
- Q91.1 Trisomy 18, mosaicism (mitotic nondisjunction)
- Q91.2 Trisomy 18, translocation
- Q91.3 Trisomy 18, unspecified
- Q91.4 Trisomy 13, nonmosaicism (meiotic nondisjunction)
- Q91.5 Trisomy 13, mosaicism (mitotic nondisjunction)
- Q91.6 Trisomy 13, translocation
- Q91.7 Trisomy 13, unspecified
Trisomy 18 and Trisomy 13 (Q91)
Q92 Other trisomies and partial trisomies of the autosomes, not elsewhere classified
- Q92.0 Whole chromosome trisomy, nonmosaicism (meiotic nondisjunction)
- Q92.1 Whole chromosome trisomy, mosaicism (mitotic nondisjunction)
- Q92.2 Partial trisomy
- Q92.5 Duplications with other complex rearrangements
Q92.6 Marker chromosomes
- Q92.61 Marker chromosomes in normal individual
- Q92.62 Marker chromosomes in abnormal individual
- Q92.7 Triploidy and polyploidy
- Q92.8 Other specified trisomies and partial trisomies of autosomes
- Q92.9 Trisomy and partial trisomy of autosomes, unspecified
Other trisomies and partial trisomies of the autosomes, not elsewhere classified (Q92)
Q93 Monosomies and deletions from the autosomes, not elsewhere classified
- Q93.0 Whole chromosome monosomy, nonmosaicism (meiotic nondisjunction)
- Q93.1 Whole chromosome monosomy, mosaicism (mitotic nondisjunction)
- Q93.2 Chromosome replaced with ring, dicentric or isochromosome
- Q93.3 Deletion of short arm of chromosome 4
- Q93.4 Deletion of short arm of chromosome 5
Q93.5 Other deletions of part of a chromosome
- Q93.51 Angelman syndrome
- Q93.52 Phelan-McDermid syndrome
- Q93.59 Other deletions of part of a chromosome
- Q93.7 Deletions with other complex rearrangements
Q93.8 Other deletions from the autosomes
- Q93.81 Velo-cardio-facial syndrome
- Q93.82 Williams syndrome
- Q93.88 Other microdeletions
- Q93.89 Other deletions from the autosomes
- Q93.9 Deletion from autosomes, unspecified
Monosomies and deletions from the autosomes, not elsewhere classified (Q93)
Q95 Balanced rearrangements and structural markers, not elsewhere classified
- Q95.0 Balanced translocation and insertion in normal individual
- Q95.1 Chromosome inversion in normal individual
- Q95.2 Balanced autosomal rearrangement in abnormal individual
- Q95.3 Balanced sex/autosomal rearrangement in abnormal individual
- Q95.5 Individual with autosomal fragile site
- Q95.8 Other balanced rearrangements and structural markers
- Q95.9 Balanced rearrangement and structural marker, unspecified
Balanced rearrangements and structural markers, not elsewhere classified (Q95)
Q96 Turner's syndrome
- Q96.0 Karyotype 45, X
- Q96.1 Karyotype 46, X iso (Xq)
- Q96.2 Karyotype 46, X with abnormal sex chromosome, except iso (Xq)
- Q96.3 Mosaicism, 45, X/46, XX or XY
- Q96.4 Mosaicism, 45, X/other cell line(s) with abnormal sex chromosome
- Q96.8 Other variants of Turner's syndrome
- Q96.9 Turner's syndrome, unspecified
Turner's syndrome (Q96)
Q97 Other sex chromosome abnormalities, female phenotype, not elsewhere classified
- Q97.0 Karyotype 47, XXX
- Q97.1 Female with more than three X chromosomes
- Q97.2 Mosaicism, lines with various numbers of X chromosomes
- Q97.3 Female with 46, XY karyotype
- Q97.8 Other specified sex chromosome abnormalities, female phenotype
- Q97.9 Sex chromosome abnormality, female phenotype, unspecified
Other sex chromosome abnormalities, female phenotype, not elsewhere classified (Q97)
Q98 Other sex chromosome abnormalities, male phenotype, not elsewhere classified
- Q98.0 Klinefelter syndrome karyotype 47, XXY
- Q98.1 Klinefelter syndrome, male with more than two X chromosomes
- Q98.3 Other male with 46, XX karyotype
- Q98.4 Klinefelter syndrome, unspecified
- Q98.5 Karyotype 47, XYY
- Q98.6 Male with structurally abnormal sex chromosome
- Q98.7 Male with sex chromosome mosaicism
- Q98.8 Other specified sex chromosome abnormalities, male phenotype
- Q98.9 Sex chromosome abnormality, male phenotype, unspecified
Other sex chromosome abnormalities, male phenotype, not elsewhere classified (Q98)
Instructional Notations
Type 2 Excludes
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
- mitochondrial metabolic disorders E88.4
