Child Neurology: Hereditary spastic paraplegia in children

Abstract

Because the medical literature on hereditary spastic paraplegia (HSP) is dominated by descriptions of adult case series, there is less emphasis on the genetic evaluation in suspected pediatric cases of HSP. The differential diagnosis of progressive spastic paraplegia strongly depends on the age at onset, as well as the accompanying clinical features, possible abnormalities on MRI, and family history. In order to develop a rational diagnostic strategy for pediatric HSP cases, we performed a literature search focusing on presenting signs and symptoms, age at onset, and genotype. We present a case of a young boy with a REEP1 (SPG31) mutation. A 4-year-old boy presented with progressive walking difficulties from the time he started walking at the age of 12 to 13 months. His family history was significant for minimal gait abnormalities with onset after age 35, occurring in the patient's mother, maternal grandfather, and maternal aunt; none of them had ever sought medical attention. Neurologic examination revealed a mildly spastic gait and marked lower limb hyperreflexia with bilateral Babinski signs present. Vibration perception was reduced at the ankles. Neurologic examination of the patient's mother and maternal aunt revealed subtle gait abnormalities with bilateral Babinski signs present. MRI of the brain and spinal cord and general metabolic screening revealed no abnormalities. Diagnostic genetic testing in both the patient and his mother revealed a pathogenic mutation (c.417 + 1 G>T) in REEP1 (SPG31) which causes a pure HSP. Mutations in ATL1 (SPG3A) and SPAST (SPG4) had previously been excluded. HSP is a genetically and clinically heterogeneous group of disorders in which the main clinical feature is progressive lower limb spasticity secondary to pyramidal tract dysfunction. HSP is classified as pure if neurologic signs are limited to the lower limbs (although urinary urgency and mild impairment of vibration perception in the distal lower …