702 Leprosy 



Very few instances are recorded in which actual inoculation has 

 produced leprosy in man. Arning* was able to experiment upon a 

 condemned criminal, of a family entirely free from the disease, in 

 the Sandwich Islands. Fragments of tissue freshly excised from a 

 lepra nodule were introduced beneath his skin and the man was 

 kept under observation. In the course of some months typical 

 lesions began to develop at the points of inoculation and spread 

 gradually, ending in general leprosy in about five years. 



S ticker f is of the opinion that the primary infection in lepra 

 takes place through the nose, supporting his opinion by observa- 

 tions upon 153 accurately studied cases, in which 



1. The nasal lesion is the only one constant in both the nodular 

 and anesthetic forms of the disease. 



2. The nasal lesion is peculiar -i.e., characteristic -and entirely 

 different from all other lepra lesions. 



3. The clinical symptoms of lepra begin in the nose. 



4. The relapses in the disease always begin with nasal symptoms, 

 such as epistaxis, congestion of the nasal mucous membrane, a 

 sensation of heat, etc. 



5. In incipient cases the lepra bacilli are first found in the nose. 

 Lesions. -The lepra nodes in general resemble tuberculous 



lesions, but are superficial, affecting the skin and subcutaneous 

 tissues. Rarely they may also occur in the organs. VirchowJ 

 has seen a case in which lepra bacilli could be found only in the 

 spleen. 



Once established in the body, the bacillus may grow in the con- 

 nective tissues and produce chronic inflammatory nodes 'the 

 analogues of tubercles; or in the* nerves, causing anesthesia and 

 trophic disturbances. On this account two forms of the disease, 

 lepra nodosa (elephantiasis graecorum) and lepra anczsthetica, are 

 described. These forms may occur independently of one another, 

 or may be associated in the same case. 



The nodes consist of lymphoid and epithelioid cells and fibers, 

 and are vascular, so that much of the embryonal tissue completes 

 its transformation to fibers without necrotic changes. This makes 

 the disease productive rather than destructive, the lesions re- 

 sembling new growths. The bacilli, which occur in enormous 

 numbers, are often found in groups inclosed within the protoplasm 

 of certain large vacuolated cells 'the "lepra cells" -which seem to 

 be partly degenerated endothelial cells. Sometimes they are 

 anuclear; rarely they contain several nuclei (giant cells). Bacilli 

 also occur in the lymph-spaces and in the nerve-sheath. 



Lepra nodules do not degenerate like tubercles, and the ulcera- 

 tion, which constitutes a large part of the pathology of the disease, 



* "Centralbl. f. Bakt.," etc., 1889, vi, p. 201. 



f " Mittheilungen und Verhandlungen der internationalen wissenschaf tlichen 

 Lepra- Konferenz zu Berlin," Oct., 1897, 2, Theil. 

 J Ibid. 



