How is dx of CSU?

Hx (shape, size of wheals, onset, associated sx, fam hx, pervious therapies) PE (assess activity, impact, control and exclude differentials) Screening (strongly advised, CBC, ESP, CRP) Medication hx (ACE inhibitors [induce angioedema repalce w/ARBs], hives duration, exacerbations after intake of NSAIDs