PMC10410414_01
Clinical picture showing dystonia in the bilateral upper limbs (a), and strabismus (b). MRI of the brain showing, symmetrical hyperintense areas in bilateral posterior putamen (arrows-c) on FLAIR, T2 Weighted sequences (arrows -d), hyperintense areas in the upper cervical spinal cord suggestive of myelomalacia (arrowheads-e) in axial T2 W images, thinning of optic chiasma with hyperintensity suggesting atrophy (arrow- f)
ABR-12-148-g001.jpg
PMC10410414_01_ABR-12-148-g001.jpg
F1
Neurological examination showed a Glasgow coma scale of 12/15, dystonia [Figure 1a], depressed deep tendon reflexes in bilateral lower limbs, strabismus [Figure 1b], and optic atrophy. W images, thinning of optic chiasma with hyperintensity suggesting atrophy [Figure 1f]. The biotinidase enzyme levels were low at -5.03 units (normal >=40 units). Whole-exome sequencing detected a pathogenic variant of the BTD gene (ENST00000643237.3): c.1553G>A(p.