58 An Introduction to Medical Mycology 



the hair follicles may be noticed yellow points which are soon observed 

 to be crusts. These yellow crusts increase in size and finally become cup- 

 shaped, when they are known as scutula. The convex side of the scutulum 

 presses down on the skin; the concave side faces outward. They are sulfur 

 colored, friable and pierced with hair. A distinctive mousy odor may be 

 readily detected. The infected hair is brittle and lusterless, but not neces- 

 sarily fractured, certainly not as extensively as with infections due to 

 Microsporum. Owing to pressure of the scutula the hair in the affected sites 

 loosens and falls out and may not return. The skin in the affected patches is 

 atrophic. When untreated, the disease spreads slowly to cover a large 

 part of the scalp. After several years there may be spontaneous cure, but 

 permanent alopecia in patches is the final result. 



In another manifestation of favus on the scalp there may be a diffuse 

 superficial but adherent scaling, with little, if any, alopecia or evidence of 

 follicular involvement. The resemblance to seborrheic eczema may be 

 striking. Since most of our patients have been adults, it is our impression 

 that this form is more apt to appear after puberty, when there is more 

 resistance to follicular infections of the scalp. It is well to keep in mind 

 the possibility of favus when a scaly condition of the scalp refuses to re- 

 spond to the remedies commonly employed in the treatment of seborrheic 

 eczema. Whittle reviewed the clinical features of cases presented in Great 

 Britain during the past few years. He concluded that atypical and minimal 

 manifestations, with scutula rarely present, may lead to an error in diagnosis. 



(8) Trichophyton gypseum.— While rare in New York, instances of in- 

 fection with this micro-organism are observed more commonly in other 

 parts of the country, particularly in the Middle West. The chief charac- 

 teristic is a violent inflammatory reaction, ordinarily with the development 

 of kerion. There is usually a history of contact with an infected animal. 

 Familial infections may occur, in which case each member may have a 

 particular manifestation unlike the others. In a family which came under 

 our observation a boy had a widespread infection simulating psoriasis 

 and involving, among other areas, the hands, feet and face; another child 

 had kerion and a third child tinea glabrosa of an eczematous type (Fig. 13). 



(c) Dermatophytid ( microsporid, trichophytid).— Jadassohn, in 1911, 

 before the Swiss Medical Congress, first described an eruption in patients 

 with kerion which consisted of small, follicular elevations, occurring either 

 in groups or diffusely, in large or small numbers, and which disappeared 

 spontaneously. There was a resemblance to lichen scrofulosorum, but the 

 histologic picture was different, and a patient's skin did not react after 

 the injection of tuberculin. There was a symmetrical distribution; the trunk 

 was the usual site, and often the extremities were involved as well. In some 



