TINEA CRURIS {DHOBIE ITCH) 



2043 



etiology. — According to Castellani's researches, at least three 

 different species of Epidermophytons and one of Trichophyton may 

 give rise to the eruption — Epidermophyton cruris CasteUani, Ep. 

 perneti CasteUani, Ep. rubrum Castellani, and Trichophyton nodo- 

 formans CasteUani — and there are probably several other not yet 

 described species. 



The description of these fungi is given in Chapter XXXVIII. (see 

 p. 1014). Attempts at experimental reproduction of the disease 

 made by Sabouraud and one of us in human beings and monkeys 

 have failed. 



Symptomatology. — The term ' dhobie itch ' is used very loosely in 

 the tropics by the lay public to denote practically any pruriginous 

 skin afiection. The term is, however, specially used to denote a 

 form of severe pruriginous affection which mostly affects the 

 inner surface of the thighs, occasionally the axillae, and, in stout 

 women, the regions under the breasts. It is in this stricter 

 meaning that the term is used by medical men practising in the 

 tropics. 



The clinical features of the affection correspond to Hebra's 

 ' eczema marginatum.' In a well-marked case the perineum, 

 scrotum, and the inner surface of the thighs present large festooned 

 patches, with an elevated abrupt margin; the whole of the patches 

 are bright red, or, in a later period, the margin only is red, while 

 the rest of the patch is of a fawnish colour, or even of normal colour. 

 The pruritus is unbearable. Owing to scratching, a secondary 

 pyogenic infection or an eczematous-like dermatitis may develop. 

 The disease, if not properly treated, is extremely chronic; the 

 condition improves during the cold season, but gets worse again 

 during the hot months. Patients who suffer badly from dhobie 

 itch may get almost well in a few days, without any treatment, 

 on going to the hills; on returning to the plains the pruritus and all 

 the other symptoms reappear. The affection has been known to 

 last for many years. It is to be noted that after a time the eruption 

 may spread to the other parts of the body — the abdomen, the 

 trunk, legs, etc. In such situations it may develop in rings, or 

 may form solid elevated dark red patches; while the disease may 

 be clinically indistinguishable from ordinary tinea circinata. In 

 some cases, though rarely, the eruption starts first on the chest 

 and arms, and from there spreads later to the armpits and cruro- 

 inguinal regions. 



Clinical Varieties. — The above description mostly applies to the 

 disease as produced by Epidermophyton cruris, which is the com- 

 monest fungus found, and by Ep. perneti. In the cases due to Ep. 

 rubrum the affected parts often present from the very beginning 

 an eczematoid appearance. The edge is perhaps not so raised as 

 in other types of tinea cruris, but very abrupt, made up of numerous 

 rather small, close-set papules, covered at times by minute bloody 

 crusts due to scratching. The eruption may also be present in 

 the shape of large complete or incomplete gyrations enclosing normal 



