Childhood-Onset Hereditary Spastic Paraplegia (HSP): A Case Series and Review of Literature.

BACKGROUND: Hereditary spastic paraplegia (HSP) encompasses several rare genetic disorders characterized by progressive lower extremity spasticity and weakness caused by corticospinal tract degeneration. Published literature on genetically confirmed pediatric HSP cases is limited. METHODS: We conducted a retrospective review of childhood-onset HSP cases followed in the neuromuscular clinics at Children's and Emory Healthcare in Atlanta. Clinical presentation, family history, examination, electrodiagnostic data, neuroimaging, genetic test results, comorbidities, and treatment were recorded. RESULTS: Sixteen patients with HSP (eight males, eight females) with a mean age 19 years ± 15.7 years were included. Ten patients (66%) presented with gait difficulty. Seven (44%) were ambulatory at the last clinic follow-up visit with an average disease duration of 7.4 years. Genetically confirmed etiologies included SPAST (3 patients), MARS (2), KIF1A (2), KIF5A (1), SACS (1), SPG7 (1), REEP1 (1), PNPT1 (1), MT-ATP6 (1), and ATL1 (1). Symptom onset to genetic confirmation on an average was 8.2 years. Sensory motor axonal polyneuropathy was found in seven patients, and two exhibited cerebellar atrophy on magnetic resonance imaging (MRI) of the brain. Neurological comorbidities included developmental delay (n = 9), autism (n = 5), epilepsy (n = 3), and attention-deficit/hyperactivity disorder (n = 2). CONCLUSIONS: In our study, a significant proportion (70%) of subjects with childhood-onset HSP had comorbid neurocognitive deficits, polyneuropathy with or without neuroimaging abnormalities, and rare genetic etiology. Genetic diagnosis was established either through inherited genetic neuropathy panel or whole-exome sequencing, which supports the utility of whole-exome sequencing in aiding in HSP diagnosis.

The Effects of Radiation and Sex Differences on Adaptive Functioning in Adult Survivors of Pediatric Posterior Fossa Brain Tumors.

OBJECTIVE: Radiation therapy (RT) improves rates of survival of patients with childhood brain tumors but increases deficits in cognition and independent living skills. Previous literature has studied difficulties in basic cognitive processes, but few explore impairment in higher-order skills such as adaptive functioning. Some studies identify females as at risk for cognitive deficits due to RT, but few investigate sex differences in adaptive functioning. It was hypothesized that females would exhibit poorer long-term independent living skills and core cognitive skills relative to males following RT. METHODS: Forty-five adult survivors of posterior fossa childhood brain tumors (24 females) completed the Wechsler Abbreviated Scale of Intelligence (WASI-II), Wechsler Memory Scale, Third Edition (WMS-III) Digit Span Forward (DSF) and Backward (DSB), and Oral Symbol Digit Modalities Test (OSDMT). Informants completed the Scales of Independent Behavior-Revised (SIB-R). RESULTS: DSF and OSDMT were positively correlated with all five SIB-R domains, full-scale IQ (FSIQ) was positively correlated with four SIB-R domains, and DSB was positively correlated with three SIB-R domains. There was an interaction between sex and RT for OSDMT and community living skills with trend level interactions for personal living skills and broad independent living skills, where females without RT had higher scores than females with RT. CONCLUSIONS: Female survivors were more affected by RT than males across the community living skills domain of adaptive functioning as well as processing speed. Processing speed deficits may have a cascading impact on daily living skills. Future studies should investigate how clinical and biological factors may contribute to personalized treatment plans between sexes. (JINS, 2019, 25, 729-739).

Organizational Strategies Partially Account for Race-related Differences in List Recall Performance.

OBJECTIVE: Organizational strategies have been shown to improve one's ability to recall items from a list. Specifically, use of semantic clustering, the tendency to group items by category when recalling them, predicts better free recall of word lists after short and long delays. The present study utilized a healthy adult sample to examine use of efficient memory strategies as a predictor of differences in neurocognitive findings between African American and white participants. METHOD: Participants provided demographic information and completed the California Verbal Learning Test-Second Edition (CVLT-II) and Wechsler Abbreviated Scale of Intelligence-Second Edition (WASI-2). RESULTS: Groups were matched across socioeconomic status and years of education. White participants used more semantic clustering and performed better on recall measures after short and long delays than their African American peers, and semantic clustering predicted recall in both groups. Regression analyses suggested that use of semantic clustering is a significant partial mediator of the relationship between race and free recall abilities. Intelligence scores from the WASI-2 were correlated with CVLT-II measures in white participants but not African American participants. CONCLUSIONS: Despite quantitatively similar backgrounds, white and African American participants differed in recall performance. However, this study showed that African American participants' poorer recall may be partially attributed to less frequent use of semantic clustering as a strategy. These discrepancies may be rooted in inequalities in educational experiences and suggest that providing organizational strategies during early learning may be an area of intervention to mitigate racial differences seen in neuropsychological testing.