826 THE NEEVOUS SYSTEM. 



reports three cases in which symptoms of Landry's paralysis followed lymphangitic 

 abscesses from excoriation of lower limbs. He considers these cases of " myelic locali- 

 zation of a streptococcus infection." Remlinger describes a case in which the strepto- 

 coccus was detected in the spinal-cord substance by cultivation and by stained sections. 

 Remlinger also states that he has induced symptoms of an acute ascending paralysis 

 in rabbits by inoculating them with pus from a septic abscess. 



INFLAMMATION OF THE KEEVES. (Neuritis.} 



In the nerves, as in the brain and cord, degenerative changes commonly accompany 

 inflammation, and a distinction is often difficult. The difficulty in sharp differentiation 

 ues in the fact that degenerative changes in nerves, when intense or long continued, 

 often lead to inflammations, and that inflammatory conditions in nerves often determine 

 secondary degenerative changes in the nerve fibres. 



Acute Exudative Neuritis. Acute inflammation of the nerves may oc- 

 cur as the result of injury, or it may be secondary to an inflammatory 

 process in their vicinity, although, owing to the dense lamellar sheaths 

 and the special blood supply, the nerve trunks may escape participation 

 in even very severe inflammatory processes in surrounding tissues. The 

 inflamed nerve may be red and swollen and infiltrated with serum and 

 pus cells. The process may undergo resolution or terminate in destruc- 

 tion of the nerve, or it may become chronic and result in the formation 

 of new connective tissue. Degeneration and regeneration of the nerve 

 fibres, similar to those described as following division of nerve trunks, 

 may occur in acute neuritis. 



" Multiple Neuritis " (Degeneration). While for convenience of refer- 

 ence described under its usual title, this lesion is probably always a de- 

 generation, and would be properly classified under the head of neurone 

 degenerations of toxic origin. It is caused by the action of certain ruin 



FIG. 542. DEGENERATION OF NERVE FIBRES IN MULTIPLE NEURITIS. 



From a case of alcohol poisoning. Specimen stained with osmic acid. The broken-down medullary sheath 

 and fat droplets are stained deep black. 



eral poisons, for example, alcohol and lead. It occurs as a complication 

 of, or succedaneum to, certain infectious diseases, for example, diph- 

 theria, septicaemia, measles, smallpox, etc. It is sometimes apparently 

 idiopathic. Changes of a degenerative nature are found in the peripheral 

 nerves, and are more marked near the periphery than near the cord. 

 Thus the most common nerves affected are the anterior tibial and the 

 radial. The most marked changes are in the nerves themselves, there 

 being little or no change in the connective tissue. More rarely, espe- 

 cially in very acute cases, there are reddening and swelling with some in- 

 flammatory reaction in the interstitial tissue. The fibre lesion shows best 

 in specimens treated with osmic acid and teased in glycerin (Fig. 542). 

 Here the niyelin sheath is seen to be broken up, and instead of a contin- 

 uous envelope of black stained niyelin, the myeliu is represented by larger 





