24 CLINICAL APPLIED ANATOMY. 



mucous membranes without producing any lesion at their 

 point of entry. 



The bronchial glands are remarkably liable to infection in 

 childhood. In early years the afferent lymphatics are more 

 permeable, and the pulmonary lymphatics in particular have not 

 yet been choked with dust and carbon particles. Moreover, the 

 occurrence of lung inflammations connected with whooping 

 cough, measles, and other infectious diseases to which children 

 are prone, renders the adjacent glands susceptible. By some it 

 is believed that these glands may be directly infected from the 

 trachea or oesophagus. 



The invasion of cervical glands is partly explained by the 

 frequency of trivial lesions of the mouth, fauces, and scalp, the 

 presence of enlarged tonsils and carious tooth sockets, and the 

 exposure of these parts to infection by food or air. If a deep 

 gland of the neck is primarily infected, the deeper lymphatics 

 following the great vessels constitute the track of infection ; if 

 the primary infection is of a superficial gland, the glands in 

 immediate relation with this are next involved. 



Primary involvement of the mesenteric glands naturally sug- 

 gests food infection. 



Tuberculosis of the inguinal glands is rare. When it does 

 occur it is usually the result of tuberculous affection of the 

 external genital organs. 



Widely disseminated glandular tuberculosis is sometimes due 

 to infections brought to the glands by the blood stream. 



The firm capsules of lymphatic glands for a long time protect 

 the surrounding tissues from invasion ; when the capsule is 

 perforated local extension follows. 



Disseminated Miliary Tuberculosis. Disseminated tubercu- 

 losis results when the blood-vessels or the lymphatic channels 

 are invaded by the bacilli. In the former case the secondary 

 deposits are widespread, in the latter more or less localised. The 

 direct invasion of the large blood-vessels by numerous tubercle 

 bacilli is the usual basis of widespread miliary tuberculosis ; for 

 small vessels tend to become thrombosed during invasion, and so 



