case_images: PMC11824531_01
case_images: Clinical and genetic profile of the patient. A: The patient exhibited high arches in both feet, a condition known as pes cavus. B: Segregation analysis confirmed that the patient had compound mutations in the SACS gene. C: OCT of both eyes revealed a thickened RNFL above the 95th percentile. D, E, and F: Brain MRI revealed cerebellar atrophy (D, arrowhead) and pontine linear T2-hypointensities in the bilateral paramedian area (E and F, arrows) (D, sagittal T1; E, axial T2; F, axial T2-FLAIR). RNFL, retinal nerve fiber layer; TMP, temporal; SUP, superior; NAS, nasal; INF, inferior; OCT, optical coherence tomography; MRI, magnetic resonance imaging; FLAIR, fluid attenuated inversion recovery.
case_images: jmd-24054f1.jpg
case_images: PMC11824531_01_jmd-24054f1.jpg
case_images: f1-jmd-24054
case_images: On physical and neurological examinations at outpatient clinics at age 33, she exhibited pes cavus (Figure 1A), and the Babinski signs of both feet were extensors, implying upper motor neuron involvement. SACS gene revealed one pathogenic variant (P) and one variant of unknown significance (VUS): c.2439_2440del, p.Val815Glyfs*4, heterozygote (P), and c.10897T>G, p.Phe3633Val, heterozygote (VUS). Segregation analysis was performed on the patient's parents, who were found to be heterozygous carriers, and the patient was compound heterozygous for the SACS variants (Figure 1B). This finding supports the diagnosis of ARSACS rather than other genetic disorders presenting with ataxia, such as Friedreich ataxia and spinocerebellar ataxia (Figure 1C). Brain magnetic resonance imaging (MRI) also revealed characteristic findings of ARSACS, including cerebellar atrophy (Figure 1D) and linear T2-hypointensities in the bilateral paramedian pons (Figure 1E and F).