Ree eee 
ett, 
364 
Lesions in the hair follicles—It is common for hair follicles to be. 
involved in the vesicle of varicella, but the process is at times so limited 
that it does not reach the surface of the skin. This occurred in two 
lesions excised. In one was an early process affecting the sebaceous gland 
and hair sheath. (PI. II, fig. 8.) In this lesion were all the forms of 
cell degeneration already described. There was but slight infiltration 
with wandering endothelial cells and no vesicle formation. In another 
lesion similarly situated the sebaceous gland and the lower portion of 
the hair sheath were infiltrated with endothelial cells and there was a 
small chamber containing fluid. In places the cell degeneration could 
be made out to such an extent as to identify the process as varicella. 
Lesions about the ducts of sweat glands.—These ducts are involved in 
a great many lesions. They may be seen at points along the base of 
the vesicle (Pl. ITI, fig. 15), or portions may persist within the chamber 
of the vesicle. Some of the minute foci are found about the epidermal 
portion of these ducts. (Pl. I, fig. 4.) In such instances the cells 
lining the duct are unaffected while the process is confined to the 
epidermis which surrounds it. In no case was the characteristic initial 
change of the process found in these ducts. 
Vesicle infected by bacteria.—A certain number of lesions do not heal 
immediately after the full development of the vesicle. The contents 
becomes white and opaque and the vesicle is topped with a central crust. 
Vesicles presenting such an appearance have probably been ruptured, so 
that bacteria have gained access, although it is possible that bacterial 
infection may in some instances occur without the vesicle being ruptured. 
Such lesions exend slowly, the central crust becomes Jarger and sur- 
rounded by a pustular ring. The depression of the central crust as 
compared with the elevated pustular periphery furnishes a form of 
umbilication. It is plain that this lesion is secondary to varicella and 
has nothing to do with the active process. The umbilication is therefore 
of a false variety. On account of the inadvisability of excising such 
lesions, only one small lesion of this character was obtained. In this 
the pustule contents was composed almost wholly of polymorphonuclear 
leucocytes. The corium forming the base of the pustule was infiltrated 
throughout with these leucocytes and there was considerable destruction 
of tissue in the papillary layer. It seems probable that the permanent 
sears, which are not an uncommon sequence of varicella, result from 
lesions of this type. In the milder, uncomplicated lesions, in which the 
papillary layer is not preceptibly damaged, the regeneration of the de- 
stroyed epithelium constitutes perfect repair and no scar is produced. 
The earliest changes in the varicella process are associated with 
cytoplasmic and nuclear inclusions which are found in epidermal cells, 
endothelial cells in situ within the blood vessels and lymphatics as well 
as those which are found migrating in the tissue, connective-tissue cells, 
pigment cells, and eosinophiles. 
