A 3-year-old boy is brought to the office by his parents due to behavioral difficulties. His mother says, "He is physically healthy and affectionate but has become more defiant and often resists our instructions about getting ready for bed. He plays roughly with his 6-year-old brother and throws tantrums when he has to share his toys or put them away." His preschool teacher describes him as an "active child" who sometimes talks out loud to classmates while the teacher is speaking. He is easily distracted and often gets up to walk around the classroom. The patient is able to draw circles, speak 3-word sentences, go up stairs with alternating feet, and use the toilet but cannot wipe himself. His parents express concern about his inability to dress himself and about his bed-wetting that occurs approximately twice a week. Physical examination is unremarkable. Which of the following is the most likely explanation for the child's behavior?
This boy's behavior is most consistent with age-appropriate behavior. His motor, language, and social skills are within normal range for a 3-year-old. A short attention span, increased motor activity (eg, difficulty staying seated), occasional impulsivity (eg, speaking out of turn, tantrums when toys are taken), and oppositional behavior at bedtime are consistent with normal developmental variation in young children.
Due to the overlap of normal behavior in preschoolers and symptoms of attention-deficit hyperactivity disorder (ADHD), this diagnosis is not given before age 4-5 (Choice A). If symptoms of inattentiveness, hyperactivity, and impulsivity continue and persist through kindergarten and cause impairment in at least 2 settings (eg, school and home), then further evaluation for ADHD and other behavioral disorders is appropriate.
(Choices B and F) In conduct disorder, the basic rights of others or major societal norms are violated (not seen in this patient). This boy's oppositional behavior at bedtime and fighting with his sibling are common at his age. Assisting parents to set consistent limits with age-appropriate consequences can be helpful in managing this behavior. The diagnosis of oppositional defiant disorder is reserved for children and adolescents with a persistent pattern of irritability, defiance, and vindictiveness.
(Choice C) This patient's developmental milestones are on track. Children are not expected to fully dress themselves or achieve nocturnal urinary continence until approximately age 5.
(Choice D) Disruptive mood dysregulation disorder is characterized by a persistently irritable or angry mood and temper tantrums that are inconsistent with developmental level.
Educational objective:
Short attention span and varying degrees of hyperactivity and impulsivity are commonly seen in children under age 4. Attention-deficit hyperactivity disorder should not be diagnosed until age 4-5.