Palpable purpura is seen in all of the following conditions, EXCEPT:
Purpura occur when red blood cells extravasate into the dermis, as a result, the lesions do not blanch with pressure. Thrombocytopenia is associated with non palpable purpura. Palpable purpura can be caused by vasculitic and embolic causes. Vasculitic cause includes leukocytoclastic vasculitis, polyaeritis nodosa and wegners granulomatosis. Infectious emboli due to, meningococcus, gonococcus, enterobacteriaceae, staphylococcus, rickettsia and candida and other oppounistic fungi are associated with palpable purpura. Purpura associated with embolic events are irregular in outline when compared to those of LCV, which are circular in outline. Ref: Harrison's Internal Medicine, 18th Edition, Chapter 53; The Washington Manual Internship Survival Guide By Thomas M. DeFer, Bryan A, 3rd Edition, Page 131
Thrombocytopenia
Small-vessel vasculitis
Acute meningococcemia
Disseminated gonococcal infection