CHAPTER XXXVIII 

 RINGWORM 



Trichophyton Tonsurans (Malmsten) 



Tinea trichophytina, ringworm of the scalp, herpes tonsurans, 

 tinea circinata, ringworm of the body, herpes circinatus, 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 comprehended under the general term dermatomycosis, and 

 are caused by closely related forms of parasitic fungi, whose generic 

 and specific differences are matters of considerable uncertainty. 



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 saprophytic, while others pene- 

 trate more deeply and are undoubtedly 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 deplor- 

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

 plicated and the use of terms too loose to permit of systematic re- 

 construction. 



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 i860 by Hebra,t between the epi- 

 thelial cells. The organism appears to have been called Trichophy- 

 ton 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 which four others have since been added, so that there 

 are now described, with or without justification, Trichophyton 

 crateriforme, T. acuminatum, T. violaceum, T. effractum, T. ful- 

 matum, T. umbilicatum, T. regulare, T. pilosum, T. glabrum, T. 

 sulphureum, T. polygonum, T. exsiccatum, T. circonvulatum, T. 

 flavum, and T. plicatili. 



In general it is customary to divide the organisms into two groups, 

 Trichophyton microsporon and T. megalosporon, the former having 

 large, the latter small, spores. 



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



t " Handbuch der spezullen Path. u. Therapie von Virchow," m, i860. 

 t"Ann. de dermat. et de syphilis," 1892, iii; 1893, rv; 1894, v; "Monats- 

 hefte," 1896, 576; "La Practique dermatologique. Trichophytie," 1900. 



7S2 



