Progressive spinal cord involvement in Leigh syndrome due to an NDUFV1 variant

Spinal cord involvement in Leigh syndrome (LS) due to an NDUFV1 variant has rarely been reported. The patient is a 4-month-old girl who developed generalized weakness, decreased vigilance, lethargy, cyanosis and unresponsiveness. Investigation revealed lactic acidosis, mild hyponatremia, normocytic anemia, elevated troponin, elevated pro-brain natriuretic peptide, Mobitz II block, systolic dysfunction, and pulmonary hypertension. Cerebral MRI showed symmetrical T2 hyperintensities in the brainstem and supra-tentorial, suggestive of LS, as well as T2 and STIR hyperintensities of the fasciculus gracilis and posterior and lateral gray matter horns, which were hypointense at T1. Seventeen days later, these lesions were more pronounced on T2 and STIR than before. Genetic testing revealed the compound heterozygous variants c.1162+4A>C and c.1138G>C in NDUFV1. In summary, mutations in NDUFV1 can also manifest phenotypically in the spinal cord and present clinically with sensory disturbances, spasticity and spinal ataxia. In patients with LS due to NDUFV1 variants, not only imaging of the brain but also of the spinal cord should be performed.