Diagnosis

The name should be confined to the simple affection we have described, and should not be used in connection with any other distinct disease that happens to be complicated with minute haemorrhagic effusions.

Scurvy should never be mistaken for purpura, or vice versa. In the former disease the limbs are swollen and tense, and the haemorrhages form diffuse patches rather than macules. The gums also are swollen, and ready to bleed at the slightest provocation. Purpuric blotches are likewise met with in speliosis rheumatica; but the pronounced arthritic symptoms serve as a mark of distinction.

Petrone found single, small, ovoid micrococci in the blood of a young man who was suffering from purpura haemorrhagica rheumatica febrilis. Some of his blood was subcutaneously injected into a rabbit. After two days numerous haemorrhagic spots appeared in the skin of one ear. By this experiment Petrone thinks he has demonstrated the infectious nature of the disease.