Abstract
Fragile X syndrome (FXS) is the most common hereditary cause of intellectual disability
in males, with an estimated prevalence of 1:4000. Epilepsy occurs in 10 to 20% of
males with FXS and usually has a favorable prognosis and positive response to antiepileptic
medication. Numerous anomalies in the central nervous system have been reported in
FXS. Among these, periventricular heterotopia (PH) has been reported in two previous
cases. Epilepsy is also a common comorbidity in PH, but in contrast to epilepsy in
FXS, the severity may vary markedly. We present a boy with FXS, PH, and epilepsy—a
combination not previously reported in the literature. The presented case suggests
a necessity to consider PH in cases of refractory epilepsy or status epilepticus in
patients with FXS, emphasizes the importance of ruling out FXS in children with intellectual
disability even if there are only discreet or no clinical signs of the disorder, and
underscores that FXS should be considered in patients with PH if no other cause can
be found.
Keywords
fragile X syndrome - periventricular heterotopias - epilepsy
