Monthly Archives: April 2026

Anny Vo, Celia Buetens, and John Jeong 

4/3/2026 

Case Study #7: Mitochondrial Citric Acid Cycle Disorder in Skeletal Muscles

Case Background¹ 

A male infant at your hospital has failed a hearing test and developed permanent hearing loss. His development was delayed as shown by an exaggerated Moro response (startle reflex) and his height was below the 3rd percentile. He was given supplemental vitamins, such as thiamine and riboflavin. At 5 months, he had motor weakness and hypotonia. At 10 months, he had feeding problems, recurrent emesis (vomiting), and metabolic acidosis from elevated lactate. 

Lab Findings¹

Key Words: SUCLA2, Anaplerotic Therapy, methylmalonic acid, succinylcarnitine

Analysis 

Q1. Based on the Lactate and Pyruvate lab results, what type of dietary change would you recommend to help reduce the lactic acidosis in this patient?

Biochemistry¹ 

Sanger sequencing revealed that the patient has a compound heterozygous mutation in SUCLA2. Mutations in this gene lead to a deficient succinyl-CoA synthetase, and therefore the accumulation of succinyl-CoA, along with methylmalonic acid and succinylcarnitine, both of which are succinyl-CoA–related metabolites.…