Cardiac symptoms in a child should raise a high index of suspicion of hyperthyroidism, based on the results of a single-center study that also found prominent behavioral and mood issues in many children with the diagnosis.
Hyperthyroidism was diagnosed in more than half the children referred for a work-up for cardiac symptoms, based on a retrospective chart study conducted at the University of California, Davis, by Dr. Lindsey Loomba-Albrecht, of the department of pediatric endocrinology, and her associates.
Further, cardiac symptoms—tachycardia/heart palpitations, shortness of breath on exertion, chest pain, and/or syncope—were present in nearly a quarter of 68 children diagnosed with hyperthyroidism over an 8-year period.
Goiter, weight loss, gastrointestinal and neurologic symptoms, and fever or heat intolerance were also represented as common presenting complaints among the diagnosed children, who ranged in age up to 18 years. A few were diagnosed as a result of screening laboratory tests or exophthalmos, Dr. Loomba-Albrecht reported at the Western regional meeting of the American Federation for Medical Research.
In pediatric textbooks, cardiac indications are listed as possible symptoms of hyperthyroidism but they appear far down on a list of symptoms that typically includes heat intolerance, emotional lability, short attention span, tremors, increased appetite, ophthalmologic symptoms, flushed skin, sweating, and muscle weakness.
“Delayed diagnosis occurred in many due to the time spent evaluating suspected cardiac disease,” Dr. Loomba-Albrecht, said in an interview following the meeting.
Because of the high incidence of cardiac symptoms investigated in children with hyperthyroidism, Dr. Loomba-Albrecht and her associates are recommending that thyroid screening labs be considered in all children with cardiac symptoms.
Severe behavioral and mood symptoms were also strikingly common in the cohort, regardless of whether these symptoms brought the child to medical attention.
Mood and behavioral symptoms were the presenting concern in just 4 of 68 pediatric patients with hyperthyroidism, but 14 of the 68 (20.5%) had major psychological issues at the time of diagnosis, reported Dr. Loomba-Albrecht.
Four were in juvenile hall; seven had major depression, and three had demonstrated antisocial behavior (including one with concomitant severe anxiety).
The prevalence of mood and behavior disturbances in the children with hyperthyroidism was far greater than what was seen in gender-matched controls who were seen in the endocrinology clinic for pubertal or growth problems (20.5% vs. 1.5%), she noted.
“For comparison, 3% of children in the general population have a mood disorder and 1%-2% have generalized anxiety or panic disorder,” she said.
Dr. Loomba-Albrecht highlighted the case of a 13-year-old boy brought into the emergency department with multiple injuries sustained while “car surfing,” in which juveniles perform dangerous maneuvers while holding onto the outside of a vehicle.
During his stay in the emergency department, the teenager experienced sustained tachycardia “of unclear etiology.” A CT scan of the neck revealed an enlarged thyroid gland, previously unnoticed because he had been placed in a protective cervical spine collar during transport.
Graves' disease was confirmed by a laboratory work-up.
Looking back, the boy's parents noted that his behavior had become quite erratic over the previous several months, resulting in plummeting school grades.
“The percent with behavioral problems prior to development of the hyperthyroidism is unknown, but the timing of symptoms suggests that the hyperthyroidism caused the behavior manifestations in most cases.
“Hyperthyroidism should thus be considered whenever a child is evaluated for behavior change,” the team advised.
None of the researchers reported any conflicts of interest regarding the study.