Paediatric-onset hereditary spastic paraplegias: a retrospective cohort study

Schiavoni S, Spagnoli C, Rizzi S, Salerno GG, Frattini D, Pisani F, Fusco C. Paediatric-onset hereditary spastic paraplegias: a retrospective cohort study. Dev Med Child Neurol. 2020 Apr 10. doi: 10.1111/dmcn.14547. [Epub ahead of print]

Abstract

AIM:

To describe the clinical and neurogenetic spectrum of paediatric-onset hereditary spastic paraplegias (HSPs) diagnosed in our unit.

METHOD:

We report on 47 patients (30 males, 17 females; mean [SD] age 12y 7mo [6y 2mo], range 4-34y) clinically diagnosed with an HSP at the Child Neurology Unit, IRCCS-ASMN (Reggio Emilia, Italy) between 1990 and 2018, who were genetically investigated by means of single-gene direct sequencing and/or next-generation sequencing technologies (targeted panels, whole-exome sequencing [WES]).

RESULTS:

Complex forms prevailed slightly (n=26), autosomal dominant being the main inheritance pattern (n=11), followed by recessive (n=5) and X-linked (n=1). A definite genetic diagnosis was achieved in 17 patients. Spastic paraplegia 3A (n=4) was the most frequent cause of autosomal dominant HSP in our cohort, while no genetic variant prevailed in autosomal recessive forms and pathogenic/likely pathogenic variants were disclosed in a wide range of different genes.

INTERPRETATION:

We found wide phenotypic and genetic heterogeneity. With increasing accessibility to WES, a higher number of patients receive a diagnosis, allowing detection of variants in ultra-rare disease-causing genes and refining genotype-phenotype correlations.

WHAT THIS PAPER ADDS:

A genetic diagnosis of paediatric-onset hereditary spastic paraplegia was achieved in one-third of patients. Pathogenic/likely pathogenic variants in rare genes were found. Genotypic and phenotypic heterogeneity favours targeted panel/whole-exome sequencing for diagnosis.

Courtesy of:  https://www.mdlinx.com/journal-summary/paediatric-onset-hereditary-spastic-paraplegias-a-retrospective-cohort-study/2D3bdku4NrGyAOa6MYdsax