A boy with drug-resistant epilepsy and aortopulmonary collateral arteries arising from a KCNT1 variant

Background

KCNT1 variants are associated with drug-resistant epilepsy, including epilepsy in infancy with migrating focal seizures, and may be associated with aortopulmonary collateral arteries (APCAs). Deaths due to hemoptysis caused by disrupted APCAs have also been reported.

Case report

The patient had seizures since 1 month of age. Interictal EEG reveals a suppression-burst pattern. At 3 months of age, echocardiography revealed abnormal blood flow originating in the aorta and a dilated left side of the heart, and contrast-enhanced CT showed numerous APCAs. A targeted sequence analysis revealed a variant of KCNT1 (NM_020822.3:c.1130G>C p.Cys377Ser) at 8 months of age. His seizures were refractory and occurred frequently daily, and he had severe psychomotor retardation. Coil embolization for APCAs was performed four times since 4 months of age, and he had never experienced hemoptysis.

Discussion/Conclusion

The complications of drug-resistant epilepsy and APCAs should be considered in cases of KCNT1 variants. APCAs can be challenging to diagnose in the early postnatal period, and regular cardiovascular evaluations are necessary. Early embolization of APCAs prior to pulmonary hemorrhage onset may effectively prevent pulmonary hemorrhage and mitigate heart failure.