MORBID ANATOMY 



1653 



they are in the septa, and a similar infiltration may be seen at times 

 around the bronchi. 



The ovaries and testes may show infiltrations and fibrosis of the 

 interstitial tissue, which destroys the secretory elements, and 

 causes the sterility which is usually so marked among lepers. The 

 lymphatic glands are often enlarged, infiltrated, and full of bacilli, 

 especially the femoral. Nephritis and leprous infiltration of the 

 kidneys may be seen. The nerves most commonly affected are the 

 palmar branch of the ulnar, the ulnar, the median, the peroneal, 

 posterior tibial, and the great auricular. When exposed, the nerve 

 is seen to show a fusiform, reddish-grey swelhng, which, when 

 examined, is found to consist of lepromatous tissue lying among the 

 nerve fibres. 



In the spinal cord there may be posterior sclerosis and meningitis, 

 though it is doubtful whether these are really due to the disease 

 or to some complication. The cells of the posterior cornu have 

 been said to be atrophied, as well as those of the anterior cornu, 

 in which Lie has found bacilh. 



In the circulatory organs periarteritis and endarteritis are 

 met with, while osteomyelitis, necrosis, caries, and absorption of 

 the bones may be seen, and will be mentioned again later. Trophic 

 changes in the joints and perforating ulcers are met with in the 

 nerve form of the disease. 



For a long time the presence of lepromata in the lung was dis- 

 puted, but recently it has been proved that the lungs can become 

 infected with leprotic lesions. The lesions of leprotic lungs are 

 very similar to those of tubercular lungs, but are more solid, caseate 

 less frequently, and are less prone to be destroj^ed. Some of the 

 earliest signs are petechial haemorrhages, which upon microscopical 

 examination show a diffuse, small, round-celled infiltration, with 

 occasionally a giant cell, but without fibrosis, but with a shght 

 cellular exfoliation in the surrounding alveoli and congestion of the 

 bloodvessels and capillaries. In these areas there are numerous 

 intracellular leprosy bacilli (Wise). In addition there may be an 

 acute and at times caseating parenchymatous inflammation or 

 chronic diffuse interstitial inflammation. These are distinguished 

 from similar tubercular affections by inoculation into guinea-pigs 

 with negative results. 



Symptomatology. — The incubation period is entirely unknown, 

 and must necessarily remain so until the method of infection and 

 the date of the onset of the disease is discovered; hence the state- 

 ments made by the different observers that it may last for a few 

 weeks or months up to many years. The method of invasion is 

 also quite unknown. Sticker suggests that it begins with nasal 

 symptoms — ^blocking of the nose, epistaxis, and frontal headache; 

 other observers with skin eruptions. The truth appears to be 

 that, so far, the initial lesions and their symptoms, if any, have 

 escaped notice. 



Before the eruption appears there are, in many cases, attacks of 



