1. Home
  2. ICD-10-CM Codes List
  3. F01–F99
  4. F70-F79
  5. Unspecified intellectual disabilities (F79)

Unspecified intellectual disabilities (F79)

The ICD-10 code F79 is used to classify cases of unspecified intellectual disabilities when a precise diagnosis or cause is not identified. This code helps document intellectual functioning impairment that does not fit more specific categories.

Intellectual disabilities under F79 may be connected to various underlying conditions often described by synonyms such as intellectual functioning disability, low intelligence, below average intellect, or complex syndromes involving neurological, skeletal, or developmental abnormalities. For medical coders and healthcare professionals, recognizing that terms like intellectual disability syndrome, congenital heart disease with intellectual disability, or developmental delay with intellectual disability may all be encompassed under this unspecified category aids accurate use of the ICD-10 code. This code captures intellectual disabilities when the precise etiology; such as genetic syndromes, brain malformations, or metabolic issues; is unknown or not specified in records.

Instructional Notations

Inclusion Terms

These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.

  • Mental deficiency NOS
  • Mental subnormality NOS

Clinical Terms

The following clinical terms provide additional context, helping users better understand the clinical background and common associations for each diagnosis listed in this section. Including related terms alongside ICD-10-CM codes supports coders, billers, and healthcare professionals in improving accuracy, enhancing documentation, and facilitating research or patient education.

Arachnodactyly

An abnormal bone development that is characterized by extra long and slender hands and fingers, such that the clenched thumb extends beyond the ulnar side of the hand. Arachnodactyly can include feet and toes. Arachnodactyly has been associated with several gene mutations and syndromes.

Hypertelorism

Abnormal increase in the interorbital distance due to overdevelopment of the lesser wings of the sphenoid.

Intellectual Disability

Subnormal intellectual functioning which originates during the developmental period. This has multiple potential etiologies, including genetic defects and perinatal insults. Intelligence quotient (IQ) scores are commonly used to determine whether an individual has an intellectual disability. IQ scores between 70 and 79 are in the borderline range. Scores below 67 are in the disabled range. (from Joynt, Clinical Neurology, 1992, Ch55, p28)

WAGR Syndrome

A contiguous gene syndrome associated with hemizygous deletions of chromosome region 11p13. The condition is marked by the combination of WILMS TUMOR; ANIRIDIA; GENITOURINARY ABNORMALITIES; and INTELLECTUAL DISABILITY.

X-Linked Intellectual Disability

A class of genetic disorders resulting in INTELLECTUAL DISABILITY that is associated either with mutations of GENES located on the X CHROMOSOME or aberrations in the structure of the X chromosome (SEX CHROMOSOME ABERRATIONS).