Section : Conference Notes

Lucio’s phenomenon in Hansen’s Disease (Leprosy)

  • Rare variant of lepromatous leprosy usually found in Mexico and Costa Rica. Also detected in Canada, Singapore, Brazil and Myanmar.
  • Historical facts:
    • described in 1852 by Lucio and Alvarado
  • Etiology
    • All described cases of Lucio’s phenomenon were caused by Mycobacterium lepromatosis which is more frequent in lepromatous leprosy and is the most common type of Leprosy in Mexico.
    • Microscopically, it is a form of vasculitis: more exactly a necrotizing variant of erythema nodosum leprosum (ENL) (this was found in 1948 by Latapi and Zamora)
  • Presentation:
    • It occurs 1 to 3 years after the onset of leprosy
    • On the face:
      • Infiltrated shiny skin on the face can be seen – it is also also called Lepra Bonita (Pretty Leprosy) (Described by Latapi in 1936)
      • Madarosis=loss of eyebrows
      • this leads early phase to a disappearance of wrinkles (Pretty Leprosy). In later stages, the skin becomes sagging and wrinkled.
    • It can be preceded by livedo reticularis which can be anywhere but which is more frequent on the lower legs which can lead afterwards to ulcers with a jagged (reticulated) border. Ulcers take 1-2 months to heal with MDT and heal with atrophic scars.
    • polyneuropathy and destructive rhinitis are common
    • hand and feet can be puffy and swollen


Dr Christophe Hsu – dermatologist. Geneva, Switzerland

Eng CS. Lucio Leprosy – Revisited. Leprosy and other Mycobacteriosis – Status Update. 2014 (4) – 21st Regional Conference of Dermatology; Danang (Vietnam)