Jervell and Lange-Nielsen Syndrome Manifesting as Seizure-Like Episodes in Childhood.

Jervell and Lange-Nielsen syndrome (JLNS) is a rare autosomal recessive form of congenital long QT syndrome (LQTS) characterized by prolonged QT interval and congenital bilateral sensorineural deafness. We report the case of an eight-year-old boy with recurrent convulsions and syncope, unresponsive to antiseizure treatment. He had a history of congenital bilateral sensorineural deafness and the sudden death of a sister. His ECG revealed a markedly prolonged QT interval of 680 ms (corrected QT interval: 650 ms). A diagnosis of JLNS was made, and propranolol was initiated. The parents were counseled on avoiding emotional and physical triggers and referred for consideration of an implantable cardioverter-defibrillator. JLNS can mimic epilepsy caused by arrhythmia-induced cerebral hypoperfusion, leading to convulsions. Such episodes can be distinguished from epilepsy by their brief duration, syncope preceding convulsions, and a family history of LQTS or sudden unexplained death. This case highlights the need for a high index of suspicion in such cases, as early diagnosis through detailed history, ECG, and clinical evaluation, even without genetic confirmation, is lifesaving and essential to reduce the risk of sudden cardiac death.