A 21-month-old boy with a family history of parental consanguinity and two siblings having died of a progressive neurological disorder was investigated for a neurometabolic disease because of recent loss of gait and lack of intellectual progress. While a lysosomal disease could not be verified, his clinical findings were compatible with infantile neuroaxonal dystrophy, the diagnosis of which was electron microscopically established by demonstrating typical enlarged axonal terminals in rectal biopsy tissue.