Characteristics of Pathogenic Fungi 283 



1 7. I [ormodendrum pedrosoi 



IS. 1 [ormodendrum compactum 



L9. Phialophora \ errucosa 



20. Actinomyces boA is 



21. Sporotrichum schencki 



22. Blastomyces dermatitidis 



23. Histoplasma capsulatum 



24. Coccidioides immitis 



25. Paracoccidioides brasiliensis 

 •26. Torula histolytica 



27. Rhinosporidium seeberi 



It is of interest that these fungi are rarely found on the normal skin or 

 its appendages. The studies of Hopkins and Benham, of Burgess, of Stumpf 

 and of Downing and his eo-workers point to the fact that the flora of the 

 skin contains many filamentous and yeastlike fungi but that these are almost 

 always saprophytes. Our observations are in agreement with the conclusions 

 of these workers. In the series of 100 patients studied by Downing, Nye 

 and Cousins, material from three different sites on each patient was cul- 

 tured. In only two of 300 specimens were pathogenic fungi demonstrated. 

 Burgess reported that in cultural studies of 100 patients he failed to find a 

 single pathogen on normal skin. Cornbleet obtained scrapings from the 

 webs between the fourth and fifth toes of 100 young adults apparently free 

 from tinea pedis. In three instances pathogenic fungi were recovered: 

 E. inguinale twice and M. audouini once. From his repeated failure to 

 find them on the hands and feet of 50 normal persons, Stumpf concluded 

 that pathogenic fungi do not live there as saprophytes. 



The isolation of one of these pathogenic micro-organisms from significant 

 pathologic tissue serves as conclusive evidence of the cause of the disease 

 without the necessity of further proof. 



BIBLIOGRAPHY 



Downing, I. (■.: Nye, K. V. and Cousins, S. M.: Investigation of fungous flora of apparentlj 

 normal skins. Arch. Dermat. e\ Svpli. 35:1087, 1937. 



1. MICROSPORUM AUDOUINI 



This fungus may be termed the classic cause of ringworm of the scalp. 

 It is endemic in many countries, being chiefly found in the larger cities. 

 Epidemics of tinea capitis in schools, foundling homes and other institu- 

 tions are usually caused by this fungus. It is the cause in approximately 40 

 per cent of cases of ringworm of the scalp seen in dispensaries in New York. 



