Background The disease course and long-term outcome of patients with organic acidurias
(OAD) and urea cycle disorders (UCD) are incompletely understood. Aims To evaluate the
complex clinical phenotype of OAD and UCD patients at different ages. Results Acquired
microcephaly and movement disorders were common in OAD and UCD highlighting that the
brain is the major organ involved in these diseases. Cardiomyopathy [methylmalonic (MMA)
and propionic aciduria (PA)], prolonged QT c interval (PA), optic nerve atrophy [MMA …

Background The clinical presentation of patients with organic acidurias (OAD) and urea
cycle disorders (UCD) is variable; symptoms are often non‐specific. Aims/methods To
improve the knowledge about OAD and UCD the E‐IMD consortium established a web‐
based patient registry. Results We registered 795 patients with OAD (n= 452) and UCD (n=
343), with ornithine transcarbamylase (OTC) deficiency (n= 196), glutaric aciduria type 1
(GA1; n= 150) and methylmalonic aciduria (MMA; n= 149) being the most frequent diseases …