Respiratory chain complex I deficiency: An underdiagnosed energy generation disorder

Abstract

Objective: To define the spectrum of clinical and biochemical features in 51 children with isolated complex I deficiency. Background: Mitochondrial respiratory chain defects are one of the most commonly diagnosed inborn errors of metabolism. Until recently there have been technical problems with the diagnosis of respiratory chain complex I defects, and there is a lack of information about this underreported cause of respiratory chain dysfunction. Methods: A retrospective review of clinical features and laboratory findings was undertaken in all diagnosed patients who had samples referred over a 22- year period. Results: Presentations were heterogeneous, ranging from severe multisystem disease..