BACKGROUND AND PURPOSE:
Single large-scale mitochondrial deletion syndrome (SLSMD) comprises devastating mitochondrial diseases often classified into 3 major clinical syndromes: Kearns-Sayre syndrome (KSS), chronic progressive external ophthalmoplegia (CPEO), and Pearson syndrome (PS). Nevertheless, there remains large clinical variability and overlap among these SLSMD groups. Therefore, further stratification is required for more precise prognostication and clinical management. Through detailed…