title: Comparison of electrophysiological findings in axonal and demyelinating Guillain-Barre syndrome.
abstract: BACKGROUND
  Incidence and predominant subtype of Guillain-Barre syndrome (GBS) differs geographically. Electrophysiology has an important role in early diagnosis and prediction of prognosis. This study is conducted to determine the frequent subtype of GBS in a large group of patients in Iran and compare nerve conduction studies in axonal and demyelinating forms of GBS.
  
  
  METHODS
  We retrospectively evaluated the medical records and electrodiagnostic study (EDS) of 121 GBS patients who were managed in our hospital during 11 years. After regarding the exclusion criteria, patients classified as three groups: acute inflammatory demyelinating polyneuropathy (AIDP), acute motor axonal neuropathy (AMAN), and acute motor sensory axonal neuropathy (AMSAN). The most frequent subtype and then electrophysiological characteristic based on the time of EDS and their cerebrospinal fluid (CSF) profile were assessed.
  
  
  RESULTS
  Among 70 patients finally included in the study, 67% were men. About 63%, 23%, and 14% had AIDP, AMAN, and AMSAN, respectively. AIDP patients represented a wider range of ages compared with other groups. Higher levels of CSF protein, abnormal late responses and sural sparing were more frequent in AIDP subtype. Five AMSAN patients also revealed sural sparing. Conduction block (CB) was observed in one AMAN patient. Prolonged F-wave latency was observed only in AIDP cases. CB and inexcitable sensory nerves were more frequent after 2 weeks, but reduced F-wave persistency was more prominent in the early phase.
  
  
  CONCLUSIONS
  AIDP was the most frequent subtype. Although the electrophysiology and CSF are important diagnostic tools, classification should not be made based on a distinct finding.
authors.affiliation: Department of Neurology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Samira
authors.initials: S
authors.lastname: Yadegari
authors.affiliation: Department of Neurology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Shahriar
authors.initials: S
authors.lastname: Nafissi
authors.affiliation: Department of Neurology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Neda
authors.initials: N
authors.lastname: Kazemi
keywords: Cerebrospinal Fluid; Electrophysiology; Guillain-Barre Syndrome; Nerve Conduction Study