s p e c i a l f e a t u r e – h i s t o r y o f n e u r o l o g y Hansen’s bacillus mice developed the disease. Koch announced in 1876 that he had proved this bacterium JMS Pearce MD, FRCP caused anthrax. He went on to identify the Emeritus Consultant Neurologist, Department of Neurology, Hull Royal Infirmary, UK. bacterial causes of tuberculosis (1882), and cholera(1883). Correspondence to: Gerhard Armauer Hansen (1841-1912) J.M.S. Pearce, 304 Beverley Road Anlaby, East Yorks, HU10 7BG, UK. worked at St. Jørgen’s hospital in Bergen, Email:
[email protected] striving to find the cause of leprosy. Importantly, Hansen’s identification of M. leprae preceded Conflict of Interest statement: None declared. Koch’s seminal investigations.5 Leprosy is a Date first submitted: 23/1/18 chronic mycobacterial infection that affected Acceptance date: 4/2/18 millions of people, mainly in Brazil, India, and To cite: Pearce JMS, ACNR 2018;17(4);16-18 Indonesia. The Tuberculoid or paucibacillary type shows well-expressed cell-mediated immunity that controls bacillary multiplication by forming Figure 2: Gerhard Armauer Hansen. 1900s Abstract epithelioid-cell granulomas. The lepromatous (Photo by Mondadori Portfolio via Getty Images) Because of its gradually declining incidence or multibacillary type shows cellular anergy many UK physicians rarely encounter leprosy towards M. leprae, thus profuse bacillary Hansen also observed visual impairment which is thus easily overlooked. Hansen’s multiplication. Between these is a continuum, or blindness now known to result either from discovery of mycobacterium leprae, the first varying from borderline tuberculoid, through mycobacterial infiltration of the anterior identified human bacterial infection, was borderline, to those with little cellular response, segment of the eye, or from trophic changes of crucial importance.