280 



TUBERCULOSIS 





V- 



>r 



bacillus of "chronic bovine pseudo-tuberculous enteritis," the lesions 

 produced by it being corrugated thickenings of the mucous membrane, 

 especially of the small intestine. The disease has now been observed in 

 various countries, and several cases in Britain have been recorded by 

 M'Fadyean. The bacilli occur in large numbers in the lesions, and can 

 readily be found in scrapings from the surface. They resemble the 

 tubercle bacillus in appearance, but on the whole are rather shorter ; they 

 are equally acid-fast. The organism has not yet been cultivated outside 

 the body. 



Smegma Bacillus. This organism is of importance, as in form and 

 staining reaction it somewhat resembles the tubercle bacillus and may be 



mistaken for it. It occurs 



^, / often in large numbers in 



the smegma preeputiale and 

 in the region of the external 

 genitals, especially where 

 there is an accumulation of 

 fatty matter from the secre- 

 tions. Morphologically it is 

 a slender, slightly curved 

 organism, like the tubercle 

 bacillus, but usually dis- 

 tinctly shorter (Fig. 85). 

 Like the tubercle bacillus, it 

 stains with some difficulty 

 and resists decolorisation 

 with strong mineral acids. 

 Most observers ascribe the 

 latter fact to the fatty 

 matter with which it is 

 surrounded, and find that 

 if the specimen is treated 

 with alcohol the organ- 

 ism is easily decolorised. 

 Czaplewski, however, who 



claims to have cultivated it on various media, finds that in culture it 

 shows resistance to decolorisation both with alcohol and with acids, and 

 considers, therefore, that the reaction is not due to the surrounding fatty 

 medium. We have found that in smegma it can be readily decolorised 

 by a minute's exposure to alcohol after the usual treatment with sulphuric 

 acid, and thus can be readily distinguished from the tubercle bacillus. 

 We, moreover, believe that minor points of difference in the microscopic 

 appearances of the two organisms are quite sufficient to make the 

 experienced observer suspicious if he should meet with the smegma 

 bacillus in urine, and lead him to apply the decolorising test. Difficulty 

 will only occur when a few scattered bacilli retaining the fuchsin are 

 found. 



Its cultivation, which is attended with some difficulty, was first effected 

 by Czaplewski. On serum it grows in the form of yellowish -grey 

 irregularly rounded colonies about 1 mm. in diameter, sometimes 

 becoming confluent to form a comparatively thick layer. He found that 

 it also grew on glycerin agar and in bouillon. It is non -pathogenic to 

 various animals which have been tested. 



Cowie has recently found that acid- fast bacilli are of common occur- 



FIG. 85. Smegma bacilli. Film preparation 



of smegma. 

 Ziehl-Neelsen stain, x 1000. 



