CHAPTER XXXVI. 

 RINGWORM. 



TRICHOPHYTON TONSURANS (MALMSTEN). 



TINKA trichophytina, ringworm of the scalp, herpes ton- 

 surans, tinea circinata, ringworm of the body, herpes cir- 

 cinatus, tinea unguium, onychomycosis, tinea imbricata, 

 herpes desquamans, tinea versicolor, .pityriasis versicolor, 

 erythrasma, etc., are diseases with well-marked clinical 

 manifestations and differences, all of which may be compre- 

 hended under the general term dermatomycosis, and are 

 caused by closely related forms of parasitic fungi, whose 

 generic and specific differences are matters of considerable 

 confusion. 



That certain of the diseases affect hairy parts and others 

 hairless parts of the body, that still others occur about the 

 nails, and that some are superficial and practically sapro- 

 phytic, while others penetrate more deeply and are undoubt- 

 edly parasitic, do not necessarily point any more conclusively 

 to essential differences in the infecting organisms than to 

 accidents of infection and variations in resisting power. A 

 review of the literature leaves the student with a deplorable 

 confusion of ideas, and a feeling that the synonomy is too 

 complicated and the use of terms too loose to permit of sys- 

 tematic reconstruction. 



The discovery of micro-organisms in these lesions seems to 

 have been made in 1842 by Gruby,* who found mycelial 

 threads and spores on and in the hairs, and in 1860 by Hebra,f 

 between the epithelial cells. The organism appears to have 

 been called Trichophyton tonsurans in 1845 by Malmsten. 

 The parasitology of all of the trichophyton infections was 

 thoroughly studied by Sabouraud,J and the old species, 

 Trichophyton tonsurans, divided into eleven new species, to 



* "Compt.-rendu," Paris, 1842, xv. 



t "Handbuch der spezullen Path. u. Therapie von Virchow," in, 1860. 



J"Ann. de dermat. et de syphilis," m, 1892; iv, 1893; v, 1894; 

 "Monatshefte," 1896, 576; "La Practique dermatologique. Tricho- 

 phytie," 1900. 



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