CHRONIC INFECTIOUS DISEASES. 



ulcer, and whether there be any other concomitant syphilitic disease. 

 The crusts and scabs which form in syphilis are distinguishable by being 

 much thicker, as a rule, than those of non-syphilitic origin. This is 

 generally because, beneath the dried, purulent contents of a syphilitic 

 pustule, there is usually an ulcer, the product of which also thickens 

 and dries into a scab. The kidney-shape or horse-shoe shape of specific 

 ulcers of the skin is also somewhat characteristic. This is due to the 

 healing of the sore at one edge while it spreads at another. 



The most common form of syphilitic cutaneous disease is the macu- 

 lous exanthema, the roseola syphilitica. This is an eruption of small, 

 irregular round spots of roseola, which here and there are often con- 

 fluent ; and its appearance is often preceded by a febrile disturbance. 

 The favorite seat of the rash is upon the belly, on the sides of the chest, 

 and upon the flanks. The face is hardly ever affected beyond where 

 the forehead and scalp join. At first the spots are bright red, but 

 afterward become livid and coppery. Some of them are level with the 

 skin, while others rise slightly above it. In the latter case they re- 

 semble the wales of urticaria, although, unlike the latter, they do not 

 itch. After lasting a long time, the roseola spots assume a dirty 

 brownish-red appearance, and, when they finally fade, they leave a 

 grayish-brown stain behind them. Sometimes the eruptions extend to 

 the glans penis. In the latter situation, the epidermis over the efflo- 

 rescence soon separates, leaving a bright-red, moist erosion, which 

 bleeds readily, and which is not to be confounded with the superficial 

 chancre. The roseola is one of the earliest symptoms of constitutional 

 infection. It is never seen m inveterate cases. When treated by 

 mercury, it usually subsides within four weeks. When neglected, it 

 passes over into the papulous, squamous, and pustulous forms of syphi- 

 lide. The papulous syphilide (lichen syphiliticus) is characterized by 

 its coppery-red, and frequently, in old cases, by its brownish-red color. 

 The papules are sometimes no larger than a millet-seed (miliary pap- 

 ules) ; sometimes they attain the size of a lentil (lenticular papules) ; 

 sometimes they are solitary ; sometimes they form groups, which latter 

 usually assume the form of circles, or the segment of a circle. Their 

 most common seat is the junction of the forehead with the hairy scalp, 

 although they also appear upon the trunk and extremities. When of 

 long standing, they are usually covered with scales of detached epider 

 mis. If, instead, small pustules form upon the apices of the papules, 

 the eruption is generally called acne syphilitica. Like the maculous 

 syphilide, the papulous exanthema appears early in the disease, although 

 it is sometimes observed in its later stages. In such cases, the points 

 of efflorescence are less numerous, and evince a still more marked ten- 

 dency to form circles or arcs of circles. The papulous syphilide is 



