Chapter 17

Q00–Q99: Congenital Malformations, Deformations and Chromosomal Abnormalities

Congenital Malformations, Deformations and Chromosomal Abnormalities diagnostic classification updated for 2026.

Chapter Instructions

Excludes2(Not included here. Code separately if applicable.)
  • inborn errors of metabolism (E70-E88)
Internal Codes
  • Q83.3|

    Accessory nipple

  • Q83.8|

    Other congenital malformations of breast

  • Q83.9|

    Congenital malformation of breast, unspecified

  • Q84.0|

    Congenital alopecia

  • Q84.1|

    Congenital morphological disturbances of hair, not elsewhere classified

  • Q84.2|

    Other congenital malformations of hair

  • Q84.3|

    Anonychia

  • Q84.4|

    Congenital leukonychia

  • Q84.5|

    Enlarged and hypertrophic nails

  • Q84.6|

    Other congenital malformations of nails

  • Q84.8|

    Other specified congenital malformations of integument

  • Q84.9|

    Congenital malformation of integument, unspecified

  • Q85.00|

    Neurofibromatosis, unspecified

  • Q85.01|

    Neurofibromatosis, type 1

  • Q85.02|

    Neurofibromatosis, type 2

  • Q85.03|

    Schwannomatosis

  • Q85.09|

    Other neurofibromatosis

  • Q85.1|

    Tuberous sclerosis

  • Q85.81|

    PTEN hamartoma tumor syndrome

  • Q85.82|

    Other Cowden syndrome

  • Q85.83|

    Von Hippel-Lindau syndrome

  • Q85.89|

    Other phakomatoses, not elsewhere classified

  • Q85.9|

    Phakomatosis, unspecified

  • Q86.0|

    Fetal alcohol syndrome (dysmorphic)

  • Q86.1|

    Fetal hydantoin syndrome

  • Q86.2|

    Dysmorphism due to warfarin

  • Q86.8|

    Other congenital malformation syndromes due to known exogenous causes

  • Q87.0|

    Congenital malformation syndromes predominantly affecting facial appearance

  • Q87.11|

    Prader-Willi syndrome

  • Q87.19|

    Other congenital malformation syndromes predominantly associated with short stature

  • Q87.2|

    Congenital malformation syndromes predominantly involving limbs

  • Q87.3|

    Congenital malformation syndromes involving early overgrowth

  • Q87.40|

    Marfan syndrome, unspecified

  • Q87.410|

    Marfan syndrome with aortic dilation

  • Q87.418|

    Marfan syndrome with other cardiovascular manifestations

  • Q87.42|

    Marfan syndrome with ocular manifestations

  • Q87.43|

    Marfan syndrome with skeletal manifestation

  • Q87.5|

    Other congenital malformation syndromes with other skeletal changes

  • Q87.81|

    Alport syndrome

  • Q87.82|

    Arterial tortuosity syndrome

  • Q87.83|

    Bardet-Biedl syndrome

  • Q87.84|

    Laurence-Moon syndrome

  • Q87.85|

    MED13L syndrome

  • Q87.86|

    Kleefstra syndrome

  • Q87.87|

    Hao-Fountain Syndrome

  • Q87.88|

    CTNNB1 syndrome

  • Q87.89|

    Other specified congenital malformation syndromes, not elsewhere classified

  • Q89.01|

    Asplenia (congenital)

  • Q89.09|

    Congenital malformations of spleen

  • Q89.1|

    Congenital malformations of adrenal gland

PreviousPage 16 of 18Next