Sural Sparing Pattern and Sensory Ratio as Electrodiagnostic and Prognostic Markers in Pediatric Guillain–Barré Syndrome

Abstract

Abstract Background We aimed to evaluate the presence of sural sparing pattern (SSP) and sensory ratio in pediatric Guillain–Barré syndrome (GBS), their distribution to subtypes, and their relationship with demographic and clinical features with a focus on the disability and muscle strength. Methods This single-center retrospective study was conducted on pediatric GBS patients of both sexes with 2 years follow-up and two nerve conduction studies in which SSP and sensory ratio were calculated. Three subgroups of SSP were formed by separate calculation of median (SSP-m) and ulnar (SSP-u) and both median and ulnar sensory nerve action potentials (SNAPs; SSP-total). Muscle strength and disability were evaluated with the Medical Research Council (MRC) sum score and Hughes functional grading scale (HFGS), respectively. Results SSP total was identified in 70.6% (n: 24) of the patients, while sensory ratio >1 was observed in 20 (66.7%) patients. Patients with SSP-m, SSP-u, SSP-total, or sensory ratio >1 had higher HFGS scores, while patients with SSP-m, SSP-u, or SSP-total had lower MRC sum scores. SSP parameters were significantly associated with muscle strength and disability scores in acute motor axonal neuropathy patients. Conclusion Both SSP and sensory ratio can be used for diagnostic and prognostic purposes. Disability and muscle strength are associated with SSP and sensory ratio in pediatric GBS.