J923- ^O. l6. THE NEUROLOGICAL ASPECT OF LEPROSY. IT 



The lepra bacilli are chiefly found in the most peripheral parts of the 

 nerves; in the proximal parts of the nerves bacilli are practically never 

 found (Lie). The bacilli are chiefly to be found in the inmost lamellae 

 of the perineurium and in the endoneural septa. The 'parenchymatous lesion 

 consists in degenerative changes of no specific character. The interstitial 

 changes are very slight to start with — but may gradually lead to consider- 

 able new formation of connective tissue. As regards the form Jof [these 

 interstitial changes, one can distinguish three different forms according to 

 whether the new formation of connective tissue takes place from the perin- 

 erium, from the endonerium. or from the sheaths of Schwann (Lie). 



The formation of fibrous connective tissue will in the course of 

 time press on the nerve fibres and finalh' destroy them. The interstitial 

 changes may vary to a certain extent in the course of the disease. Often in 

 comparatively early stages of the maculo-anaesthetic form, attacks of neuralgic 

 pains occur, and these attacks are generally accompanied by considerable 

 acute swelling of the corresponding nerves. Histologically this swelling is 

 seen to consist of a very considerable cellular infiltration of the interstitial 

 tissue. This acute interstitial reaction in the nerves is chiefly seen in the 

 early maculo-anæsthetic cases; but may also now and again be observed 

 in old nodular cases. In the maculo-anæsthetic cases the nerves show a 

 much stronger and quicker reaction to the invasion of bacilli than they do 

 in the nodular cases. — Apart from that, there does not seem to be any 

 fundamental difference betsveen the nerve lesions in the maculo-anæsthetic 

 and the nodular forms. 



Already Danielsen and Boeck thought they had found changes in the 

 spinal cord. Even though there ma}' be some doubt about these findings, 

 subsequent research has shown that the spinal cord in all advanced cases 

 is constanth' the seat of degenerative changes (Looft, Lie, Jeanselme, 

 Marie). These changes are chiefly found in the posterior columns — and 

 are found in nodular as well as maculo-anæsthetic cases (Lie). While Marie 

 & Jeanselme have found the degenerative changes confined to endogenous 

 medullary fibres, Looft and Lie have chiefly found the degenerative changes 

 in the exogenous fibres in the posterior columns, which would correspond 

 to the centripetal fibres from the limbs. The bacilli themselves are chiefly 

 found in the ner\-e cells in the grey substance, a few in the pericellular 

 lymphatic spaces, but nowhere else in the spinal cord (Lie). Thus there 

 does not seem to be a definite relation between the number of bacilli 

 present and the degenerative changes in the cord. 



Also the spinal ganglia have been shown to be the seat of degenera- 

 tion and sclerotic changes (Looft). Lie has found lepra bacilli in the 

 spinal ganglia in all cases where bacilli were present in the peripheral 

 nerves. 



