title: Zoster-associated mononeuropathies (ZAMs): a retrospective series.
abstract: BACKGROUND
  Zoster-associated limb paresis is an uncommon complication of herpes zoster (HZ) and one whose precise pathophysiologic mechanism is poorly understood. Occasionally, the paresis results from a zoster-associated mononeuropathy (ZAM).
  
  
  METHODS
  Mayo Clinic records between 1996 and 2010 were reviewed for patients with ZAM whose clinical, electrophysiologic, and radiographic features were then abstracted.
  
  
  RESULTS
  Ulnar (2), median (3), femoral (1), and sciatic (2) mononeuropathies were identified. Most patients had moderate to severe weakness in affected muscles, and most had post-herpetic neuralgia (88% at 1 month and 71% at 4 months). The minimum duration of weakness was prolonged (mean, 281.9 days; range, 45-1242 days). Nerve magnetic resonance imaging (MRI) was abnormal, demonstrating nerve enlargement (4/4 cases), T2 signal hypertintensity (2/4 cases), or enhancement (1/4 cases).
  
  
  CONCLUSIONS
  While ZAM is an uncommon occurrence following cutaneous HZ, it is associated with significant weakness, high rates of post-herpetic neuralgia, and prolonged morbidity.
authors.affiliation: Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, Minnesota, USA.
authors.forename: Haatem
authors.initials: H
authors.lastname: Reda
authors.forename: James C
authors.initials: JC
authors.lastname: Watson
authors.forename: Lyell K
authors.initials: LK
authors.lastname: Jones
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006562:Herpes Zoster / Q000150:complications*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020422:Mononeuropathies / Q000209:etiology* / Q000473:pathology* / Q000532:radiotherapy / Q000821:virology; D018908:Muscle Weakness / Q000209:etiology; D009431:Neural Conduction / Q000502:physiology; D010525:Peripheral Nerves / Q000503:physiopathology; D012189:Retrospective Studies