A rare case of juvenile primary lateral sclerosis

Abstract

Primary lateral sclerosis (PLS) is a rare, neurodegenerative disorder, which affects the upper motor neurons (UMN), predominantly the large pyramidal cells of corticospinal and corticobulbar tracts, common during fourth to fifth decade of life. Juvenile PLS is an autosomal recessive form with ALS2 gene mutation on 2q33.2 chromosome affecting infants and children. A 6-year-old girl presented with complaints of difficulty in walking and climbing stairs noticed by parents in the last 2 months and frequent falls associated with stiffness of lower limbs for 15 days with no other significant history. Central nervous system (CNS) examination was normal except for spasticity in bilateral lower with exaggerated lower limb reflexes with spastic gait. Baseline laboratory investigations were normal. Magnetic resonance imaging (MRI) brain and spine showed symmetrical signal abnormality along corticospinal tracts bilaterally. Diagnosis of primary lateral sclerosis was made after ruling out possible causes.