Global developmental delay in a 10-month-old infant boy

A 10-month-old boy was seen for the first time for a health supervision visit by a pediatrician. A brief review of the child's medical history did not reveal any specific problems. On physical examination, the pediatrician found an alert, smiling child, but she was surprised by the following observations: unable to sit without support, absent pincer grasp, no audible language, unilateral exotropia, and microcephaly. Expansion of the medical history revealed an uneventful full-term prenatal course and normal vaginal delivery. The mother denied use of alcohol or other drugs/medications during the pregnancy. She did not have a recent history of any infections, unexplained fevers, or high risks for sexually transmitted disease. The baby cried spontaneously and the parents reported no resuscitation efforts. There were early feeding problems associated with a poor suck and gastroesophageal reflux. The parents were healthy and this was their first child. Family history was negative for early problems in child development or any neurological conditions. Parents were high school graduates without any learning problems; they were both employed in retail sales with a steady employment history. The pediatrician then took a second look at the child and discovered truncal hypotonia, extremity hypertonia, tongue protrusion, and a broad mouth. She concluded that the child had a global developmental delay, including delays in motor, language, and social development.