title: [Linear tuberculoid leprosy along the lines of Blaschko: a very rare presentation].
abstract: BACKGROUND
  Leprosy continues to be present in certain regions throughout the world, and the dermatologist plays a central role in its diagnosis. Herein we report a case of tuberculoid leprosy that is atypical in terms of its linear presentation which appears to follow the lines of Blaschko.
  
  
  METHODS
  A patient from Mayotte was referred to the neurological department for suspected tuberculoid leprosy. He was presenting a deficiency of the ulnar nerve together with neuronal hypertrophy and cutaneous involvement. Dermatological examination revealed linear hypo-aesthetic hypopigmented lesions on the arm and forearm. The atypical clinical presentation also suggested to us pigmented mosaicism or post-inflammatory pigmentation. The biopsy showed granulomatous epithelial dermatitis with perinervous involvement. Imaging examinations confirmed the presence of neuronal hypertrophy. A diagnosis of linear tuberculoid leprosy was made.
  
  
  CONCLUSIONS
  This case illustrates the need to bear in mind a diagnosis of leprosy in the event of hypopigmented lesions, even where they are linear and of Blaschkoid appearance. Several potential hypotheses may account for this particular topographical pattern.
authors: Service de dermatologie, CHU de Nancy, rue du Morvan, 54511 Vandœuvre-lès-Nancy, France. Electronic address: annelaure.liegeon@gmail.com.
authors: A-L
authors: AL
authors: Liegeon
authors: Service de dermatologie, CHU de Nancy, rue du Morvan, 54511 Vandœuvre-lès-Nancy, France.
authors: M
authors: M
authors: Reigneau
authors: Institut européen de la main, 13, rue Blaise-Pascal, 54320 Maxeville, France.
authors: J
authors: J
authors: Rivail
authors: Service de dermatologie, CHU de Nancy, rue du Morvan, 54511 Vandœuvre-lès-Nancy, France.
authors: O
authors: O
authors: Bauvin
authors: Service de dermatologie, CHU de Nancy, rue du Morvan, 54511 Vandœuvre-lès-Nancy, France.
authors: J-F
authors: JF
authors: Cuny
authors: Service de dermatologie, CHU de Nancy, rue du Morvan, 54511 Vandœuvre-lès-Nancy, France.
authors: J-L
authors: JL
authors: Schmutz
mesh_terms: D001132:Arm / Q000473:pathology; D001706:Biopsy; D019521:Body Patterning; D017507:Comoros / Q000208:ethnology; D006801:Humans; D006984:Hypertrophy; D017496:Hypopigmentation / Q000209:etiology; D015441:Leprosy, Tuberculoid / Q000175:diagnosis* / Q000473:pathology; D008297:Male; D014375:Tuberculoma / Q000473:pathology; D014459:Ulnar Nerve / Q000473:pathology / Q000503:physiopathology; D055815:Young Adult
keywords: Blaschko; Blaschko lines; Dermatose linéaire; Hypopigmentation; Linear dermatitis; Lèpre tuberculoïde; Mosaïcisme; Tuberculoid leprosy