ABC's of I/DD Part II: Diagnoses

In the first part of this series, we introduced abbreviations and acronyms for jobs, treatments, organizations, and laws. Like those abbreviations, the meaning of diagnosis abbreviations can be meaningless without a definition and description. Some abbreviations are more common and better known, like I/DD (intellectual and developmental disability), while some abbreviations, like PKU, are better known than their long form.

Diagnoses

ADHD (attention deficit hyperactivity disorder): ADHD is a common neurodevelopmental disorder characterized by trouble paying attention, controlling impulsive behaviors, or being overly active. ADHD is often diagnosed in childhood and can be present with another I/DD diagnosis.

ASD (autism spectrum disorder): Also known as autism. ASD is a developmental disability marked by a combination of social communication problems, restrictive or repetitive behaviors, and other differences that often include unusual sensory habits or needs. This is considered a spectrum because characteristics of autism will vary from person to person. Some individuals with ASD have high support needs while others have low support needs, with a wide range in between.

CP (cerebral palsy): CP is a group of disorders that affect a person's ability to move and maintain posture or balance. The most common type is Spastic CP, which affects about 80% of people with CP. With Spastic CP, muscle tone is increased, creating stiff, awkward movements. It can affect the whole body or a part of the body.

DS (Down syndrome): Also known as Trisomy 21. This disorder is caused by an extra copy of the twenty-first chromosome. This extra chromosome causes differences in physical and mental development. They often have a distinctive appearance, with shorter than average limbs and neck, almond shaped eyes, and a flattened face or bridge of the nose. There are three types of DS, based on the type of duplication in the chromosome.

FAS (fetal alcohol syndrome): FAS occurs when a person is exposed to alcohol before birth. People with FAS may exhibit smaller facial features, have slow growth before and after birth, poor memory, difficulties with coordination, and behavioral issues. There are similar disorders that fall under the fetal alcohol spectrum disorder (FASD) label.

FXS (fragile X syndrome): Also called Martin-Bell Syndrome. FXS is a genetic disorder in which there are changes to a gene that makes a protein necessary for brain development. Symptoms often closely resemble ASD and ADHD, including delayed speech, differences in social interaction, anxiety, and hyperactive behaviors.

GAD (generalized anxiety disorder): As the name suggests, this is the official name of anxiety. While there can be specific anxieties or phobias, GAD is marked by excessive worry about everyday issues or situations. This is commonly diagnosed with other I/DD diagnoses.

HASCI (head and spinal cord injury): Another name for a TBI, but also includes a spinal cord injury. Like a TBI, a HASCI is not a disability alone, but it can cause a disability.

HI (hearing impaired): This is a general term for someone with any degree of hearing loss. Many people in the deaf or hard of hearing community do not like this term because it implies a negative impact of their hearing loss.

HOH or HH (hard of hearing): This is a term for someone with partial hearing loss. Where “deaf” usually means a person has little to no functional hearing, someone who is HOH may have enough residual hearing that a hearing aid or similar system may help them process sounds. Within the deaf and HOH community, this term is preferred over HI.

LD or SLD (learning disability or specific learning disability): LDs are a class of disability that affect the ability to learn basic skills like reading, writing, and/or math, as well as skills like organizing, time management, and memory. SLD diagnoses include dyslexia (trouble with reading), dyscalculia (trouble with numbers or math), dysgraphia (trouble with handwriting and fine motor skills), or nonverbal learning disability (trouble with understanding nonverbal cues).

MD (muscular dystrophy): MD refers to a group of more than 30 genetic diseases that cause progressive weakness and degeneration of muscles used in voluntary movement. Many people with MD eventually lose the ability to walk.

ODD (oppositional defiant disorder): a common diagnosis in conjunction with I/DD but the validity of it has been questioned due to significantly higher rates in children with I/DD versus neurotypical children. ODD is characterized by uncooperative or defiant behavior, hostile behavior toward peers or authority figures, and vindictiveness.

PKU (phenylketonuria): This inherited genetic disorder causes an amino acid, phenylalanine, to build up in the body because no enzyme is produced to break it down. People with PKU must follow a strict diet that avoids phenylalanine, which is found mostly in sources of protein. PKU can cause delays in development, intellectual disability, and neurological symptoms.

PWS (Prader-Willi syndrome): PWS is a multisystem genetic disorder caused by abnormalities in chromosome 15. It causes cognitive impairment and behavioral problems, but medical issues such as diabetes and cardiac conditions are also common with PWS.

TBI (traumatic brain injury): Also known as a concussion or acquired brain injury, a TBI is not a disability in and of itself, but a severe TBI or repeated TBIs can cause an intellectual or developmental disability. Additionally, individuals with I/DD may be at an increased risk of TBI if their disability affects balance or coordination.

VI (visually impaired): A person with VI has vision that cannot be corrected to a “normal” level. Generally, VI can be interchanged with “blind,” and it is important to remember that both terms encompass a spectrum of vision, from some vision to no vision at all.

WS (Williams syndrome): WS is a genetic disorder that affects many parts of the body, including the brain, heart, and blood vessels. Visual-spatial abilities are often affected more than verbal abilities, and comorbid diagnoses like anxiety or ADHD are common. Narrowing of blood vessels and high blood pressure are also common in WS and should be treated on an ongoing basis.

General Terms Related to Diagnoses

ND (neurodivergent): This term describes someone whose brain processes, learns, and/or behaves different than what is considered “typical.” It is a general term encompassing I/DD, mental illness, and even non-disabling differences like synesthesia. It is part of a shift away from viewing atypical neurologic patterns as an illness in favor of seeing it merely as a difference.

NT (neurotypical): this term describes someone who is not displaying characteristics of an I/DD or neurological atypical patterns of thought or behavior.

Common Abbreviations No Longer in Use

In 2013, a new diagnostic manual (DSM-5) was released, and some diagnoses were combined or eliminated. The following diagnoses were renamed or absorbed into other diagnostic criteria, but the use of these terms and abbreviations is still somewhat common, even colloquially. It is not considered correct to use these abbreviations, but none are considered offensive or incorrect currently.

ADD (attention deficit disorder): This diagnosis is no longer in use. ADHD has absorbed this diagnosis due to the similarities in symptoms.

PDD-NOS (pervasive development disability – not otherwise specified): This diagnosis is no longer in use. The PDD-NOS diagnosis has been partially absorbed by ASD. People who have this diagnosis under an old evaluation should seek out an autism assessment.