Clinical and laboratory characteristics of propionic acidemia in a Turkish cohort

Propionic acidemia (PA) is an autosomal recessive multisystem disorder caused by the deficiency of propionyl-CoA carboxylase, encoded by PCCA and PCCB genes. This retrospective study presents the clinical and laboratory characteristics of PA patients followed up in our center.

Included in the study were 50 patients diagnosed in a single center with propionic acidemia between 1984 and 2020, whose electronic and written hospital records regarding demographic, clinical, and laboratory features, along with diagnostic and therapeutic approaches, were reviewed retrospectively.

This cohort had a median age at diagnosis of 18 days and 91.1 % (n=41) were born at term. Consanguinity was notably prevalent (91.1 %), and a family history of PA was reported in 14 % of cases. No significant relationships were observed between clinical and laboratory parameters and mortality. Laboratory findings at the time of diagnosis revealed significant metabolic abnormalities, including low levels of free carnitine, elevated C3 propionyl carnitine, and varied amino acid imbalances. Twenty-three patients exhibited developmental delay and/or intellectual disability. Brain magnetic resonance imaging unveiled white matter involvement and ventricular dilatation in 9/25 patients. Furthermore, dilated cardiomyopathy (26 %) was noted in patients who had cardiac assessments. Among the study cohort, 27 patients survived, 23 patients died during follow-up. No significant relationships were observed between clinical and laboratory parameters and mortality.

Despite improvements in the understanding of the pathophysiology and advances in diagnostic and treatment approaches, propionic acidemia and its long-term complications can still lead to severe consequences. This comprehensive evaluation offers valuable insights into the multifaceted nature of PA.