title: Clinical presentation and electrophysiological findings of porphyric neuropathies: a follow-up study.
abstract: BACKGROUND
  A case series of acute intermittent porphyria (AIP) is described that focuses on the clinical course of the disease with regard to neurological manifestations of the peripheral nervous system.
  
  
  METHODS
  Eight patients were diagnosed with AIP on the basis of characteristic clinical findings, erythrocyte porphobilinogendeaminase activity, neuropathic patterns, serial changes in nerve conduction studies (NCS), and temporal relationship of central nervous system involvement.
  
  
  RESULTS
  Six patients diagnosed with AIP<2 months after symptom onset had neuropathy that was predominantly upper extremity, motor, and proximal. NCS recovery rates were slower in the lower than the upper limbs. Two patients diagnosed >2 months after symptom onset had distal sensorimotor polyneuropathy.
  
  
  CONCLUSIONS
  The findings from this case series suggest that the peripheral nerves may be differentially and selectively involved in different diagnostic stages of porphyric neuropathy.
authors.affiliation: Department of Neurology, Chang Gung Memorial Hospital and College of Medicine, Chang Gung University, 199 Tung Hwa North Road, Taipei, Taiwan.
authors.forename: Chi-Lin
authors.initials: CL
authors.lastname: Wu
authors.forename: Long-Sun
authors.initials: LS
authors.lastname: Ro
authors.forename: Shih-Ming
authors.initials: SM
authors.lastname: Jung
authors.forename: Tzung-Chang
authors.initials: TC
authors.lastname: Tsai
authors.forename: Chun-Che
authors.initials: CC
authors.lastname: Chu
authors.forename: Rong-Kuo
authors.initials: RK
authors.lastname: Lyu
authors.forename: Chin-Chang
authors.initials: CC
authors.lastname: Huang
authors.forename: Hung-Chou
authors.initials: HC
authors.lastname: Kuo
mesh_terms: D000328:Adult; D004576:Electromyography / Q000379:methods; D055724:Electrophysiological Phenomena / Q000502:physiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009431:Neural Conduction / Q000502:physiology*; D011115:Polyneuropathies / Q000175:diagnosis* / Q000503:physiopathology*; D017118:Porphyria, Acute Intermittent / Q000175:diagnosis* / Q000503:physiopathology*; D012189:Retrospective Studies; D055815:Young Adult
keywords: acute intermittent porphyria; compound muscle action potential; electrophysiological study; porphobilinogendeaminase; porphyric neuropathy