MORBUS MACULOSUS WERLHOFII 49I 



great probability that these hemorrhages have their origin chiefly in internal 

 causes, and are the expression of the so-called hemorrhagic diathesis Al- 

 though the intensity and extent of the hemorrhagic efflorescence is no exact 

 indication of the severity of the disease, observation nevertheless proves that 

 the small, isolated, and rapidly disappearing petechias represent the milder 

 type, while the more distributed and very diffuse suggillations, with a pro- 

 tracted course and a tendency to repeated relapses, indicate a more severe 

 form of the disease. At the same time, all the transitional stages from the 

 mildest to the severest of cutaneous affections may occur, and cause the body 

 to appear as if spattered with a large brush dipped in blood. There may be 

 extravasations of the size of a plate, which occasionally leave but few large 

 areas unaffected, and are of a violet to a dark red color. Deep-seated flat 

 hematomata may also arise and extend into the muscles, and over these the 

 skin presents the well-known changes of extravasated hemoglobin, showing all 

 the colors of the rainbow. Finally, streaks and strife-like " vibices " appear, 

 particularly in the flexure of the knees, which resemble analogous conditions 

 in scurvy, and which go through all the changes in tint and shade from dark 

 blue to greenish yellow. 



We have still to consider the relation of the hemorrhagic efflorescences to the 

 complications, particularly to the arthritic affections and to the gastric phe- 

 nomena. 



The appearance of the purpuric areas in the complicated cases differs in no 

 respect from ordinary purpura. Occasionally the eruption begins with the 

 appearance of typical urticaria with vesicles, which gradually become filled 

 with a hemorrhagic fluid, and soon dry in the way so well known in urticaria ; 

 the pustules then collapse and disappear without leaving residua. In other 

 cases the urticarial vesicle leaves behind it a hemorrhagic area. Occasionally 

 in the same individual alternating attacks of urticaria and purpura are noted. 

 It has often been remarked that patients who suffer from conditions of this 

 kind have previously suffered from urticaria. Sometimes the development of 

 petechise is preceded by the formation of diffuse erythema, in the course of 

 which occasional miliarial vesicles appear. 



The changes which hemoglobin undergoes in the hemorrhagic eruptions 

 of the skin correspond as a rule to the well-known processes. Occasionally, 

 however, we see very extensive suggillations of enormous size and of very 

 different ages; in such cases extraordinarily striking pictures are noted which 

 confuse the inexperienced, particularly so if recent hemorrhages are super- 

 added to old ones, which represent all the color modifications and all the tints 

 of altered blood. After absorption pigment is noted with the naked eye only 

 in those cases in which huge extravasations of blood have occurred. Even 

 this, however, disappears after some time, so that with the lapse of weeks or 

 months nothing remains to indicate the process which has taken place. The 

 conditions are different in the microscopic investigation; the pigment depos- 

 ited and accumulated in the rete Malpighii remains there for a long time, 

 so that after some months — after the disease has run its course — we are still 

 able to recognize in this area that the skin was once the seat of a decided effu- 

 sion of blood. 



