Children who are behind their peers in motor skills, speech, listening, understanding or social development are developmentally delayed, a common condition affecting 15% to 20% of children nationally.

“It’s important to identify and screen for these children, because we clearly know that earlier recognition and earlier intervention leads to significantly greater gains later in life compared with children who are identified at a much later age,” said Darren M. Farber, D.O., a child neurologist with Norton Children’s Neuroscience Institute, affiliated with the UofL School of Medicine.

A developmental delay is different from developmental disability. Children with a developmental disability have a life-long issue. They can make improvements and thrive with intervention and therapy, but they will have some sort of disability throughout their lives.

Looking at developmental delays, the five areas to consider are motor skills, speech, social skills, cognitive abilities and activities of daily living. A child with a global developmental delay has significant delays — typically two or more standard deviations — in two or more developmental domains. A child older than 5 years with this type of delay and an IQ less than 70 is considered to have an intellectual disability.

Learning disabilities can range in severity and typically fall into four categories:

• Oral languages — listening, speaking, and understanding
• Reading comprehension and decoding
• Written language and spelling
• Mathematics and computational problem-solving

Attention deficit hyperactivity disorder (ADHD) is not a learning disability by itself, according to Dr. Farber, though it’s present in about a third of children who have learning disabilities.

“Since [children with ADHD] have normal intellect, they can overcome, and they can navigate around their learning challenges by receiving appropriate therapies and services and tutoring and having educational program in place,” he said.

Lead and other causes of developmental delay

There are many possible causes of development delays and disabilities. These include an inherited condition; issues with the physical structure of the brain; issues during pregnancy such as drug exposure, infection, or an intrauterine growth restriction (IUGR); preterm delivery; issues during birth, such as hypoxia; and issues after birth including seizures, feeding or body temperature issues and exposure to lead.

“Lead certainly is an issue in many parts of Louisville, especially in the more urban areas,” Dr. Farber said.

The process for assessing children with developmental delays involves screening, surveillance and diagnostic assessment.

Screening

Screening is the process of identifying children who may need a more comprehensive developmental evaluation. This can be accomplished through commonly available assessment tools such as the Denver or Bayley scales.

Surveillance

Surveillance involves following children over time to assess the delays in their developmental course.

“This consists of listening to their parents, hearing their concerns, reviewing their developmental history and getting a thorough history in terms of where they’ve been tracking over time,” Dr. Farber said. “I’ll also look at how they interact with their parents. Are they expressing appropriate stranger anxiety? Are they comforted by their parents? Are they not making eye contact? I want to look at their vocabulary for their age. Do they have appropriate sentence structure?

“Sometimes children won’t talk to us, but they’ll follow commands. Will they identify a body part or colors, things like that? We’ll look to see if we can assess their visual assessment. Do they hold object close to their face but they’re not visually fixating?”

Diagnostic assessment

The motor exam looks at balance, strength, coordination and tone.

“Look for abnormal movements. Look at their coordination and motor planning in general … their gait and their balance and their running. I oftentimes do my examinations in the hallway, just because you have more space and you want them to run and move around and feel more comfortable,” Dr. Farber said.

Tests needed to reach a diagnosis vary from child to child, depending on the developmental issue, and could include genetics, blood, vision or hearing, electrical activity in the brain and other brain imaging.

The first-line genetic test is a comparative genomic hybridization (CGH) microarray analysis, according to Dr. Farber. Other genetic tests could include fragile X testing or targeted gene panels if the child exhibits seizure issues, ataxia concerns, or intellectual disability.

Possible neurophysiological testing includes magnetic resonance imaging (MRI) to look for signs of structural abnormalities; electroencephalography (EEG), either routine or prolonged monitoring for a child having seizures; and electromyography (EMG) or nerve conduction studies if there are concerns more of a peripheral process.

Assessing the child may involve a team that could include a neurologist, pediatrician, psychologist, geneticist, educator and a social worker.

“If we feel children need rehab services, they want to get occupational therapy, speech therapy, physical therapy, visual therapies or feeding therapies. Physical medicine and rehabilitation can be very helpful to facilitate that and have those sorts of assessments performed,” Dr. Farber said.

In addition to addressing the specific delays, intervention and treatment can help with a child’s self-esteem, self-confidence and mood issues.

“The first three years of life are the critical times in neurodevelopment. It’s when our brain is most plastic, most adaptable. And again, early intervention — early treatment — is much more effective compared with later treatment for these children,” Dr. Farber said.