K.P. is a 3-year-old female visiting your office for her well-child visit. She was born full term after a normal pregnancy and delivery. Initially, K.P. clings to her mother, but as you continue to talk, she climbs down and runs around the exam room, touching everything. When she spots an Elsa in your bag of toys, she points and says “Elsa.” As you hand it to her, she laughs and makes brief eye contact, but ignores your efforts to engage her in play, preferring to remove the doll’s crown and put it back on again.

To begin the physical exam, you call K.P.’s name several times, but she does not respond and continues to play. Her mother finally picks her up so you can measure and weigh her, and K.P. begins a tantrum that lasts 15 minutes.

K.P. is in the 75th percentile for weight and height, and her head circumference is at the 85th percentile. She has mildly hyperextensible joints. K.P. achieved early developmental motor and language milestones within expected age ranges. Her parents describe her as “precocious,” and she loves to imitate scenes from her favorite movies and TV shows.

K.P., an only child, has history of reflux and sleep disturbance. Her mother reports concerns that K.P. seems more irritable than her peers and is getting worse. At daycare, she doesn’t speak much and has hit and bit other children who don’t do things “the way she wants.”

What is your diagnosis?

Have you figured out this issue's diagnosis? Submit it below. The first person with the correct answer will be recognized in the next issue of Children's Doctor.

My Diagnosis

Congratulations to Esther K. Chung, MD, MPH, of Swarthmore, Pennsylvania, who submitted the first correct answer to last issue’s challenge, giant cell myocarditis, the subject of this issue’s cover article.