Nearly all published clinical information on patients with isovaleric acidemia (IVA) is retrospective. Prior to newborn screen half of patients presented with overwhelming acidosis, hyperammonemia, with a high incidence of mortality. Surviving patients typically had intermittent episodes of milder acidemia with or without hyperammonemia triggered by intercurrent illness. The other half of patients did not have newborn symptoms, but still experienced the later intermittent episodes. Intellectual disability is usually secondary to brain damage due to systemic stress and/or hyperammonemia.
IVD