Ring chromosome 20 syndrome with non-convulsive epileptic status phenotype.

The ring chromosome was described by Atkins in 1972, this chromosomal arrangement has an estimated frequency of 1 in 25,000-60,000 births, generally it is de novo with 1% being heritable. The clinical picture of this genetic condition is characterized mainly by the presence of refractory epilepsy, intellectual disability, and behavioral disorders. The age of onset is between 2 to 4 years of age and is generally not associated with a phenotype or particular dimorphism at birth.The presence of a triad consisting of treatment-resistant frontal lobe epilepsy, recurrent non-convulsive status epilepticus, and classic EEG manifestations has been described. A clinical case of a patient with drug-resistant seizures with a diagnosis of ring chromosome 20 is presented, with a normal magnetic resonance and an electroencephalographic pattern characterized by long-duration shocks with slow waves, with frontal spikes, as well as recurrent electroclinical activity and frontal predominance, even with the use of high doses of anticonvulsants that began at 4 years of age with a diagnosis of regressive syndrome. Currently, the patient is 14 years old, with low weight and height for his age, grade III malnutrition, failure to thrive, moderate mental retardation and the presence of seizures 3 to 4 per month, despite the use of 3 anticonvulsants.