CONSTITUTIONAL SYPHILIS. 



even though the}" appear upon notoriously syphilitic subjects, ought not 

 to be regarded as of syphilitic origin. This proposition, however, does 

 not admit of inversion. A rash need not be syphilitic because it has a 

 coppery color, as is sufficiently proved in cases of psoriasis and of acne 

 rosacea (commonly known as " copper nose," on account of its appear- 

 ance). The origin of this color is to be attributed to the addition to 

 the redness, caused by the capillary hyperaemia, of yellow, blue, and 

 brown pigment, the result of minute extravasations of blood, and the 

 metamorphoses of the haematin thus set free. In very recent cases the 

 coppery hue is not observable, no extravasations having as yet oc- 

 curred, or because the effused blood has not yet undergone change of 

 color. 



Another characteristic of the syphilitic exanthemata (which is 

 closely related to the foregoing one, as it also depends upon gradual 

 transformation of the coloring matter of extravasated blood into pig- 

 ment) is, that, after they have recovered, stains of pigment are almost 

 always left in the skin. 



Syphilitic eruptions may be further distinguished from non-syphilitic 

 ones, from their type being still less distinctly marked than that of the 

 latter. In the same subject we almost always find patches which be- 

 long in part to one and in part to another species, and here and there 

 a spot about which we shall be in doubt what category to assign it to 

 For instance, there are often red spots which we hesitate to call roseola / 

 because they are covered with scales of epidermis ; but, on the other 

 hand, we cannot regard them as psoriasis, because their coat of epi- 

 dermic scales is so much thinner than in the non-syphilitic psoriasis. 



The situation of the efflorescence is also of great importance in dis- 

 tinguishing between the simple and the specific eruptions. The spe- 

 cific exanthemata are most apt to appear upon parts of the skin which 

 are exposed to the air, and upon such as lie immediately above the 

 periosteum. It is a very suspicious circumstance, when a rash which 

 has a peculiar predilection for certain localities as psoriasis has for 

 the knees and elbows appears elsewhere, upon some unusual region 

 instead of upon its favorite seat as when psoriasis affects the palms 

 of the hands. Another peculiarity of a syphilitic eruption is, that the 

 various efflorescences generally take the form of circles, or of segments 

 of circles. It is to be borne in mind, however, that it is only when 

 this circular arrangement is the result of grouping, and not when it 

 proceeds from healing of a disease in the middle while it continues to 

 spread at its edges, that it is characteristic of syphilis. Finally, it 

 may be added, that syphilitic eruptions scarcely ever itch. In order to 

 determine the question of the syphilitic origin of a doubtful case, it is 

 of importance to ascertain whether it has been preceded by a primary 



