Klinefelter's Syndrome in a 5-Year-Old Boy with Behavioral Disturbances and Seizures

Abstract

Klinefelter’s syndrome (KS) is a sex chromosomal aneuploidy with a prevalence of approximately 1 in 500 live male births. KS is characterized by a range of abnormalities, including increased height, language delay, hormonal alterations, motor coordination difficulties, and hypogonadism. Seizures affect 5% of individuals with KS and antiepileptic drug efficacy is often suboptimal. Psychiatric symptoms, including hallucinations, mood and anxiety disorders, hyperactivity, impulsivity, and autistic behaviors have also been associated with KS. 1– 8 In young children, these symptoms may be difficult to differentiate from other psychopathology. 9 Unfortunately, KS is often not diagnosed until puberty. 3 We present a case of a 5-year-old with significant behavioral disruptions and seizures who was subsequently found to have KS and a maternally inherited 15q duplication/ deletion. This case highlights a critical research gap in the treatment of medically ill children with co-morbid psychiatric conditions and reinforces the benefit of genetic testing in young children with complex neuropsychological presentations. The demonstration of a second genetic abnormality offers support for a novel hypothesis whereby the range of symptoms in KS individuals may be explained by additional structural changes in their chromosomes, potentially missed by standard karyotype testing.