Assessment of Methylcitrate and Methylcitrate-to-Citrate Ratio in Dried Blood Spots as Biomarkers for Inborn Errors of Propionate Metabolism
Al-Dirbashi, O.Y.; Alfadhel, M.; Al-Thihli, K.; et al.
Propionyl-CoA metabolic defects require early diagnosis in neonates to limit life-threatening complications. Regrettably, a specific marker for the prognosis/monitoring of propionic acidemia (PA) has yet to be proposed. Al-Dirbashi et al. therefore aimed to evaluate the potential of methylcitric acid (MCA) and its ratio to citric acid (CA) as markers of propionate metabolism disorders. The method quantified CA and MCA derivatives in patient DBS samples by RPLC-MRM/MS, with D4 CA and D3 MCA functioning as internal standards. Although further studies with larger patient cohorts are required, the novel results demonstrate that MCA and MCA/CA can serve as a potential biomarker for both PA and methylmalonic acidemia.