Landau–Kleffner syndrome with lateral temporal focal cortical dysplasia and mesial temporal sclerosis: A 30-year follow-up

A 39-year-old man, who presented at age 312 with Landau–Kleffner syndrome, had persisting oral and written language deficits into adulthood. Seizures were easily controlled in childhood, but reemerged in adulthood as medication-refractory complex partial seizures. Abnormal T2 signal hyperintensity was seen in the left mesial temporal area on brain MRI. Later, left temporal lobectomy revealed focal cortical dysplasia in the lateral temporal neocortex and gliosis plus neuronal loss in the hippocampus. This case suggests that focal cortical microdysgenesis may be a cause of the Landau–Kleffner syndrome. Persistent seizures in this illustrative case may have led to the evolution of dual-temporal-lobe pathology with mesial temporal sclerosis.