The mechanism of the neural signs and symptoms of leprosy

RESUMO

1- The signs and symptoms in leprosy such as hypopigmenation, anidrosis, keratosis, depilation, loss of sensation, paralysis, and trophic ulceration are often explained as due to degeneration of nerves, semsory, motor and sympathetic. 2- While recognizing that nerves are involved in leprosy, and that this involvement gives rise to various symptoms, the autor does not agree that degeneration of the nerves is always the cause of the conditions mentioned. The reasons for this belief are enumerated. 3- The clinical, therapeutic, and experimental work done to investigative this problem is described. 4- The results of the investigation indicate that the various signs and symptoms under discussion are due mainly to diminution of the blood circulation in the cappilaries of the skin, its appendages, the nerves, and the muscles affected by the disease. 5- It is concluded that, although these symptoms of lerposy are beyond doubt related to changes in the nerves, in a majority of cases the changes are not of the nature of degeneration of the nerve fibers. In most cases it is diminution of blood supply to the nerves that results in their dysfunction, and with the restoration of normal blood supply the function can be restored. Restoration of function is complete in some cases, but in other cases there may be actual degeneration of nerves or irreparable damage of the skin and other structures supplied by the nerve, and as a result the normal function cannot be restored or can be restored only partially. 6- The symptoms like hypopigmentation, anidrosis, keratosis, and depilation in patches probably do not depend on nerve involvement but are caused by diminished blood supply to the skin and its various appendages, and the disappearance of these symptoms and return of normal functions of the skin depend on the return of normal blood circulation to different parts of the skin.