106 A/j Introduction to Medical Mycology 



Because of mismanagement, a low state of resistance or a virulent strain of 

 organism, the condition may spread from the feet to involve contiguous 

 areas, which are sometimes of wide extent. The eruption is erythematous 

 and vesicular in patches and is fairly well demarcated from normal skin. 

 The folds and intertriginous areas are most vulnerable, and the infection 

 may spread to any or all of the following sites: the upper parts of the 

 thighs, the perianal region, the umbilicus, the axillae and the inframam- 

 mary regions. There are a few instances of primary involvement of the 

 hands and of other parts of the body. In instances of acute inflammation, 

 secondary pyogenic invasion of the tissues is common. At times the pyo- 

 genic element overshadows the characteristics of fungous disease. If the 

 process becomes frankly pyogenic and spreads, the disease may have 

 changed to infectious eczematoid dermatitis. Many clinicians believe that 

 eczematous eruptions on the hands or elsewhere may be originally of fungous 

 origin but persist owing to coincidental sensitizations or secondary pyogenic 

 involvement. It is our opinion that fungous disease predisposes to contact 

 sensitivity, so that a patient who ordinarily is not reactive to soap, dyes, 

 salicylic acid, etc., may develop an inflammatory response to these or to 

 many other drugs or chemicals, and that this superadded insult to the skin 

 is often important in accounting for the lack of response of the disorder 

 to therapy. 



b. Involvement of the nails. As part of the process, the nails, particularly 

 of the toes, are not uncommonly affected. In fact nail tissue may be the 

 first to be involved. The infection with T. gypseum may be superficial, 

 merely causing a white patch on the surface or in the substance of the 

 affected nail (leukonychia trichophytica ) . At other times there may be 

 a more inflammatory and destructive involvement, in which case the nail 

 becomes yellowish, opaque, lusterless and finally friable. The nail bed may 

 become slightly erythematous, and separation of the nail from its bed may 

 occur, this process usually beginning distally. Subungual hyperkeratosis and 

 uneven dystrophic changes in the nail are frequent. Paronychia is rare. When 

 destruction occurs, the process is fairly rapid, although there are rarely more 1 

 than three nails affected. Subjective symptoms are usually mild, but pain 

 may be severe. 



(2) Chronic type (Trichophyton purpureum) .—In this form there is prac- 

 tically never vesiculation or acute reaction. The interdigital webs alone may 

 harbor the organism, in which case the appearance does not differ no- 

 ticeably from that of the latent form described in the section on the inflam- 

 matory type, although the duration is often considerably longer. 



Further characteristics of the infection may be described from the stand- 

 point of the sites of involvement. 



