Section : History & Terminology

Incontinentia Pigmenti or Bloch-Sulzberger syndrome: who was Bloch ?

  • Dr Bruno Bloch (1878-1933) was a Swiss dermatologist who created the dermatology department in Zurich.
  • He described incontinentia pigment with the US Dermatologist, Dr Marion Sulzberger
  • But he made his most valuable contribution in pigment research.
  • Indeed he discovered that the synthesis of melanin was due to the action of an enzyme on the amino acid dihydroxyphenylalanine – he named the enzyme DOPA oxidase.
  • Dr Aaron Burner Lerner  and Thomas B. Fitzpatrick then named the enzyme tyrosinase:
    • DOPA (diydroxyphenilalanine) was in fact the amino acid tyrosine
    • DOPA oxidase was in fact tyrosinase


Dr Christophe Hsu – dermatologist. Geneva, Switzerland

Source of information:

-Crissey JT el al. Dermatology and Dermatologists (2002). Parthenon Publishing