The case of the Marquis de Causan (1804): an early account of visual loss associated with spinal cord inflammation

The recent discovery of disease specific and pathogenic autoantibodies in neuromyelitis optica (NMO, Devic’s disease) has revived the interest in this intriguing yet often devastating condition. While the history of classic multiple sclerosis has been studied extensively, only very little is known so far about the early history of NMO. Here we discuss a now forgotten report by the famous French anatomist and pathologist Antoine Portal (1742–1832), first physician to Louis XVIII and founding and lifelong president of the Académie Nationale de Médecine. Portal’s report, which fascinated some of the most renowned 19th century pioneers in the field of neurology but fell into oblivion later, represents the first account of visual loss in a patient with spinal cord inflammation but no brain pathology in the Western literature known so far––published more than 60 years prior to Thomas Clifford Allbutt’s much cited note on a patient with myelitis and a “sympathetic eye disorder”.