Disruption of early or late fetal brain development resulting in structural abnormalities
may be associated with inborn errors of mitochondrial metabolism. It is common in
patients with deficiency of pyruvate dehydrogenase activity and it has sporadically
been described in patients with dysfunction of the tricarboxylic acid cycle. Mitochondrial
respiratory chain disorders are not commonly known to interfere with early brain development.
We describe here a girl with an encephalomyopathy likely to be due to a novel type
of deficiency of cytochrome c oxidase (complex IV) activity that presented with severe
hypotonia, myoclonic seizures, optic atrophy and elevated lactate concentration in
cerebrospinal fluid shortly after birth. Cranial magnetic resonance imaging revealed
hypoplasia of the cerebellum with rudimentary cerebellar hemispheres and relative
sparing of the vermis. This case suggests that deficiency of cytochrome c oxidase
and possibly respiratory chain disorders in general have to be considered in the differential
diagnosis of cerebellar hypoplasia.
Mitochondrial respiratory chain disorder - Cytochrome c oxidase - Encephalomyopathy
- Cerebellar hypoplasia
