THE INFECTIOUS DISEASES. 



209 



This organism may be present in large numbers in the lymph-vessels, 

 especially in the borders of the inflamed region. The reasons for the 

 clinical peculiarities of this phase of inflammation are not yet very clear. 



INFECTIOUS PSEUDO-MEMBRANOUS INFLAMMATION OF MUCOUS 

 MEMBRANES. (Pseudo-Diphtheria ; Diphtheroid-Angina ; Membranous 

 Angina.) 



Under a variety of conditions, as during scarlatina and measles, 

 whooping-cough, typhoid fever, etc., or entirely apart from any compli- 

 cating disorder, an acute exudative inflammation of the mucous mem- 

 branes, especially of the upper air passages, occurs, which is associated 

 with and is apparently induced by the growth of Streptococcus pyo- 

 genes. There may be much or little fibriuous exudate ; there may in 







&?^ : -.'. 





FIG. 99. PSEUDO-MEMBRANOUS INFLAMMATION OF TRACHEA. 



In this case there is purulent infiltration of the mucosa and submucosa, and of portions of the mucous 

 glands, fl, False membrane ; b, portion of intact epithelium ; c, infiltration of the mucosa with fibrin ; cf, 

 portion of mucous gland infiltrated with pus. 



early stages, or even throughout, be none at all. The pellicle when 

 formed may be loose or adherent, sharply circumscribed or tending to 

 spread. The submucous tissue may show little change, or may be con- 

 gested and redematous, or may be the seat of suppurative inflammation 

 (see Fig. 99), necrosis, or gangrene. The process may be confined to 

 the tonsils. While under these varying conditions the inflammatory 

 process is usually a local one and runs its course with or without the 

 symptoms of septicaemia, occasionally the streptococcus which enters 

 the blood may induce the lesions of pyremia. On the other hand, it 

 may by aspiration gain access to the lungs and induce varying phases 

 of complicating broncho-pneumonia. The Staphylococcus pyogenes is 

 not infrequently associated with the streptococcus in these lesions, but is 

 not apparently of primary significance. Simulating very closely, as it 

 14 



