Studies of the skin in clinical purpura haemorrhagica have been concerned mostly with attempts to demonstrate morphologic changes in its vessels. Little has been added to the work of Unna and Sack,1 who pointed out dilatation and engorgement of the subpapillary venous plexus as the change most consistently noted in purpura. They expressed the belief that the hemorrhages originated from lacerations in the walls of these vessels, especially at the junction of the superficial part of the subcutaneous tissue with the lower part of the cutis. It is at this point that the venules lose their adventitia and lack the support of the highly elastic cutis.
The skin of dogs with purpura produced experimentally by the injection of antiplatelet serum shows definite alterations grossly. It appears flabby and loose; when it is cut, the lips of the wound sag out and a hematoma forms under them easily. These
TOCANTINS LM. FUNCTIONAL CHANGES IN THE SKIN IN EXPERIMENTAL PURPURA. Arch Derm Syphilol. 1936;34(3):459–464. doi:10.1001/archderm.1936.01470150109009
Dermatology in JAMA: Read the Latest
Customize your JAMA Network experience by selecting one or more topics from the list below.