Charles-Eugène Quinquaud
Charles-Eugène Quinquaud (26 December 1841, Lafat – 9 January 1894, Paris) was a French internist and dermatologist. He studied medicine in Limoges and Paris, receiving his doctorate in 1873. While working as a hospital interne, he was influenced by Pierre-Antoine-Ernest Bazin to study dermatology. In 1878 he became "médecin des hôpitaux", obtained his "agrégation" in 1883, and from 1886 served as "chef de service" at the Hôpital Saint-Louis in Paris. During his career, he worked closely with dermatologists Ernest Besnier, Jean Alfred Fournier and Émile Vidal. In 1892 he was elected as a member  of the Académie de Médecine. In 1888 he described folliculitis decalvans, a scalp disease sometimes referred to as "Quinquaud’s disease". His name is also associated with "Quinquaud's sign", a form of finger tremor with a sideways finger movement from the interossei. The phenomenon was first described in alcoholics, and its description was first published by a student of Quinquaud's, six years after his death. In 1882, with physiologist Nestor Gréhant, he developed a method for determining blood volume through the use of carbon monoxide.