TINEA (RINGWORM) 489 



TREATMENT. 



Small marks can be excised. Blistering and Finsen light has been 

 used. Carbon dioxide snow leaves a scar. When gunpowder is used 

 paint with di-iodide of ammonium, followed by dilute HCl. 



Persistent application of dilute acids and dilute alkalies may be 

 effectual, but it is a tedious and painful process, eventually leaving 

 a scar. 



Only a prolonged dermatitis will remove extensive tattooing. 



TINEA (Ringworm). 



A contagious inflammatory infection of the skin affecting the hair, 

 nails and, rarely, mucous membrane, caused by one of the fungi to be 

 enumerated later. 



Ringworm, which is derived from animals, is usually more inflam- 

 matory than that of human origin. 



The appearance of the lesion varies according to the part 

 aftected, as — 



(i) The hairy parts, e.g., the scalp = tinea tonsurans, so-called 

 because it resembles in outline the priestly tonsure; tinea 

 barbae, sycosis and palpebralis. 

 (2) The non-hairy parts, e.g., the body = tinea circinata, the nails 

 ^ onychomycosis, the mucous membranes of the mouth, 

 vulva, inguinal, perineal and gluteal regions = T. marginata 

 (eczema marginatum). 

 There are two families of ringworm fungi : — 

 (i) Trichophytons (large spores) (6'/?^^= hair, 0i;toj^ = fungus). 

 (2) Microsporons (small spores). 



Of these there are many species of clinical interest which will be 

 dealt with seriatim later. 



DIFFERENCES BETWEEN 

 Trichophytons and Microsporons. 



Large-spored tinea Small spored tinea 



Square or oblong Round or ovoid 



Arranged in regular chains No definite arrangement 



Regularly jointed, short, mycelium Mycelium irregularly jointed, curved 



and branching 

 Fungus first attacks root and grows up- Fungus lies about the hair as a visible 



wards, breaking the hair off short greyish sheath, destroys the shaft and 



eats down to the root 



The lesion commences in the epidermis in both cases. 

 The Endothrix tinea develops exclusively within the hair structure, 

 Endo-ectothrix tinea develops within the hair. 



