i82 DISEASES DUE TO BACTERIA 



A smooth white and brown ghstening nodule, hard from fibrosis 

 or soft from degeneration, well supplied with vessels. No true giant 

 cells. The bacilli do not invade the surface epithelium, nor the cutis 

 beneath this, nor sweat glands, nor hair sheaths superficial to the open- 

 ing of the sebaceous glands. 



In section one sees the epithelium normal, but with no inter- 

 papillary processes. 



Then larger cells of connective tissue free from bacilli. 



Then lepra cells, plasma cells, connective tissue cells, vessels with 

 little connective tissue, vessels much thickened, sometimes with the 

 lumen obliterated, and then lymph spaces dilated and filled with bacilli 

 surrounded by mucus forming the "globi." 



Beneath this is normal connective tissue. 



The leproma may break down the skin and ulcerate, disseminating 

 the bacilli in the discharge. 



Bacilli may enter the nerves, causing hyperplasia of the coats, 

 forming thickened leproma about the vasa nervorum, and later, in the 

 perineurium and endoneurium. 



These press on the nerve fibres, causing degeneration of the 

 neurilemma, and destruction of the nerve fibres, which become con- 

 verted into connective tissue. 



The bacilli may attack the anterior cornua of spinal cord. 



Any organ may be the site of leprotic lesions. 



P.M. 



Skin tubercles may or may not be ulcerated. Pigmented patches 

 may be seen. Liver enlarged, bacilli infiltrate portal systems, seen as 

 yellow dots. Spleen also. Bacilli are never found in the liver cells 

 themselves. 



Ovaries and testes may show infiltration and fibrosis of interstitial 

 tissue, which destroys sexual elements and causes the sterility so 

 marked in lepers. 



The lymphatic glands are infiltrated and enlarged. 



The ulnar, median, peroneal, post-tibial and great auricular nerves 

 are affected most. 



Posterior sclerosis of the cord and meningitis are not uncommon. 



Trophic changes in joints and perforating ulcers. 



Lungs may be affected, more solid than in T.B., caseate less 

 frequently, less prone to be destroyed. 



SYMPTOMATOLOGY. 



Incubation not known ; perhaps two or three years at least. 

 Begins usually in subjects from lo to 13 years of age, rarely after 40. 

 Sometimes children are lepers first and parents later. 



