Summary of information
Propionic aciduria (PA) is a rare disorder and the true incidence in Europe is unknown. Estimates of incidence in Western populations have ranged from 1:50,000 to 1:500,000 births, and overall incidence is believed to be ~ 1:100-150,000. In some populations across the world, this is much higher: for example incidence in Saudi Arabia is reported to be much higher at 1 in 2000 to 5000 live births.
PA is caused by the deficient activity of the enzyme propionyl CoA carboxylase, a mitochondrial biotin-dependant enzyme which is essential for the catabolism of the amino acids threonine, methionine, isoleucine, valine, as well as cholesterol and odd-chain fatty acids.
The treatment of PA is complex and requires regular monitoring and frequent therapeutic and dietary adjustments. It is recommended that the treatment and follow up of these patients be supervised by an experienced multidisciplinary team in a tertiary setting, although many aspects of care, including emergency management, can be delivered at the local or secondary level. Patients usually require 3-monthly follow up in order to monitor their clinical condition, nutritional status and growth and to make any changes to treatment as necessary. Long-term surveillance must include annual cardiac assessments because of the potential for developing cardiac arrhythmias and cardiomyopathy in later life.