SEBACEOUS OR SEBORRHailC ECZEMA. 



601 



The prognosis is grave, because large areas of the skin may be 

 invaded in succession. 



Treatment. As in acute eczema, the condition is improved by 

 the prolonged administration of small doses of salines and diuretics. 

 Arsenical preparations are also valuable, but should only be employed 

 for two or three weeks together, with intervals of equal duration. 

 The dangerous complications which sometimes result from accumula- 

 tions of this drug in the system are thus avoided. 



SEBACEOUS OR SEBORRHCEIC ECZEMA. 



Whilst the two preceding forms of eczema result from vascular 

 disturbance of the skin or dermis that now under consideration seems 



Fig. 242. — Sebaceous eczema, first stage. Dopilation of the extremities. 



due to vascular and secretory troubles in the accessory structures of 

 the skin, and more particularly in the sebaceous glands. 



Symptoms. The disease develops slowly. At first circular or 

 elliptical patches of skin, distributed regularly over the body, more 

 especially round the natural orifices, become deprived of hair. The 

 surface of these patches is covered either with thick crusts of a pecu- 

 liar greyish-brown tint which display numerous superficial cracks, or 

 parts normally free from hair exhibit shining epidermic crusts ar- 

 ranged in layers, which are shed on the slightest touch. 



This depilation has a strong tendency to spread, and so at first 

 it often resembles ringworm. It results from changes in the hair 



