title: Idiopathic polydactylous longitudinal erythronychia.
abstract: OBJECTIVE
  To describe the clinical features of idiopathic polydactylous longitudinal erythronychia.
  
  
  BACKGROUND
  Longitudinal erythronychia presents as a linear red band on the nail plate. Idiopathic polydactylous longitudinal erythronychia is a rarely described manifestation of longitudinal erythronychia in which one or more linear red bands present on the nails of multiple digits without any associated subungual malignant tumor, dermatological condition, or systemic disease.
  
  
  METHODS
  As part of a total body skin examination, the fingernails and toenails were evaluated for linear red bands.
  
  
  RESULTS
  One or more asymptomatic linear red bands (longitudinal erythronychia) was observed on multiple digits of the hands in one percent (3 men of 134 men and 112 women) of patients examined during a period of 75 days. The author also noted similar changes of his own nails. Between 3 to 10 digits were affected. Multiple linear red bands per nail were usually narrow (less than 1mm wide), whereas a single band on a nail often ranged from 4 to 6mm wide. The intensity of an individual wider linear red band was position-dependent in three individuals in whom the distal portion appeared less prominent when the affected digit was held upward above the level of the patient's heart-pseudolongitudinal erythronychia. Other nail changes in these patients included distal subungual hyperkeratosis, fissuring at the free end of the nail, leukonychia, red lunula, and splinter hemorrhages.
  
  
  CONCLUSIONS
  Idiopathic polydactylous longitudinal erythronychia is a benign, usually asymptomatic, condition of undetermined etiology characterized by one or more linear red bands originating at the proximal nail fold or distal lunula and extending to the free edge of the nail. It appears to be more prevalent in men over 50 years of age and its incidence was noted to be one percent of adults attending a dermatology clinic. Patients are either unaware of the nail changes or seek medical attention because of the nail plate appearance. Other nail changes can concurrently be observed including pseudolongitudinal erythronychia in which the distal intensity of an individual wider red band is less pronounced when the digit is held upward. Idiopathic polydactylous longitudinal erythronychia has not been associated with benign or malignant subungual tumors, dermatological conditions, or systemic diseases.
  
  
  CONCLUSIONS
  Idiopathic polydactylous longitudinal erythronychia may represent as a benign, possibly age-related, nail change without any associated local or systemic adverse sequellae.
authors.affiliation: The University of Houston Health Center, University of Houston, Houston, Texas; The Department of Dermatology, The University of Texas M.D. Anderson Cancer Center, Houston, Texas; and The Department of Dermatology, University of Texas-Houston Medical School, Houston, Texas.
authors.forename: Philip R
authors.initials: PR
authors.lastname: Cohen