ICD-10-CM > G00-G99 > G70-G73 > G71 > G71.3 G71.3 Mitochondrial myopathy, not elsewhere classified Billable/Specific Copy Code Copy Description Type 1 Excludes Kearns-Sayre syndrome (H49.81)Leber's disease (H47.21)Leigh's encephalopathy (G31.82)mitochondrial metabolism disorders (E88.4.-)Reye's syndrome (G93.7)