Complex II Deficiency
Long Name: Succinate dehydrogenase deficiency
Symptoms: Encephalomyopathy and various manifestations, including failure to thrive, developmental delay, hyoptonia, lethargy, respiratory failure, ataxia, myoclonus. Lactic acidosis common. May cause Leigh Syndrome.
Cause: Probably autosomal recessive
Links: https://rarediseases.info.nih.gov/diseases/5053/mitochondrial-complex-ii-deficiency