Kearns-Sayre Syndrome Misdiagnosed as Myasthenia Gravis

Abstract

Kearns-Sayre syndrome is a rare mitochondrial deletion syndrome characterized by triad of cardiac conduction defects, chronic progressive external ophthalmoplegia and pigmentary retinopathy. We present a 15 years old child who was diagnosed and treated as myasthenia gravis for several years and currently presented with complete heart block. He was finally diagnosed as having KSS on mitochondrial genome sequencing analysis. Thus, KSS and MG are mimics and a high suspicion of KSS should be kept in patients who are diagnosed as MS and additionally have cardiac problems.