Pycnodysostosis: the disease of Henri de Toulouse-Lautrec

Pycnodysostosis or Maroteaux–Lamy syndrome is a genotypic bone disorder, with autosomal recessive inheritance, individualized by Lamy and Maroteaux in 1962. It is characterized by diffuse condensation of the skeleton with thickening of the cortex and narrowing of the medullary cavity. This condensation is reminiscent of the one observed in Albers-Schönberg disease, which differs essentially in dysmorphism of the skull (no closure of fontanelles, gaping sutures, hypoplasia of the lower jaw with open mandibular angle) and extremities (hypoplasia or osteolysis of the phalanges). The patients have a short stature, short hands and feet, and malformed nails. The first scientifically correct diagnosis was made by Dr. G. Séjournet who, under the guidance of his teacher Professor J.-A. Lièvre, performed extensive research and diagnosed Henri de Toulouse-Lautrec with achondroplasia-related dwarfism. This article describes pycnodysostosis and reports the life of the painter Henri de Toulouse-Lautrec who died from the disease.