Purpura Hemorrhagica

Question 1

Describe the epidemiology of purpura

Answer 1

Affects mostly young adult horses. No sex or breed predisposition. Most often occurs as a rare complication following a case of strangles. Can occasionally develop after strangles vaccination in hypersensitive horses

Question 2

Describe the pathology of purpura

Answer 2

Two things are a prerequisite for Purpera: a magnified immune response and a large amount of antigens. Most often associated with a strangles infection. It is a type III hypersensitivity. Results from the formation of immune complexes between the horses antibodies and bacterial components.

Question 3

Describe the clinical presentation of purpura

Answer 3

Follows 2 to 4 weeks after a case of strangles. Presenting with depression and anorexia followed by urticaria and swelling around the nares. Localized swelling is followed by severe SQ edema of the head abdomen and limbs. Edema of the limbs can lead to skin necrosis.

Question 4

What are some other clinical signs of severe purpura

Answer 4

Dyspnea, tachycardia, fever, petechial hemorrhage around nares

Question 5

How do you treat purpura

Answer 5

Dexamethasone, antibiotics, NSAIDS, leg wraps, hydrotherapy

Question 6

What is the mortality rate for Purpera

Answer 6

7.5%

Question 7

What is purpura hemorrhagica

Answer 7

Immune mediated vasculitis in horses. A condition of subcutaneous edema and hemorrhage triggered by a type III hypersensitivity response to antigen antibody complexes