BOF: 37 (2.30)
A 35-year-old Japanese male presents with anterior
uveitis. There is a history of recurrent oral ulceration and he has also had
ulcers on his scrotum that have resulted in scarring.
To further investigate the patient’s condition a 20 G
needle is inserted into the skin of his forearm. A positive result in this
test is:
a)
A blister appearing at the site if injury in 24-48 hours
b)
A weal appearing at the site of injury immediately
c)
Multiple petechiae appearing at the site of injury within 5 minutes
d)
A papule or pustule appearing at the site of injury within 24-48 hours
e)
An erythematous nodule appearing at the site of injury within 24-48
hours
Answer:
d)
The clinical features suggest that the patient has
Behcet’s disease. In this condition
pathergy is often demonstrable. Pathergy refers to an excessive inflammatory
reaction to non-specific injury. In a positive test, insertion of a 20 G
needle into the skin of the forearm results in a papule or pustule within
24-48 hours
Revision Tip
Revise Behcet's disease KEYS to
SUCCESS in Medicine page 515-517
