Clinical QuickieDermatology
Rash Assessment — First Pass
Describe the rash before naming it.
Start with morphology
Macule, papule, plaque, vesicle, pustule, wheal, petechia, purpura, scale, crust, and erosion narrow the differential.
Distribution is diagnostic data
Localized vs generalized, flexural vs extensor, dermatomal, acral, mucosal, sun-exposed, and intertriginous patterns matter.
Symptoms and timing matter
Pruritus, pain, fever, medication timing, exposure, travel, sick contacts, and speed of spread change the differential.
Red flags come first
Mucosal involvement, skin pain, blistering/sloughing, purpura with systemic illness, rapidly progressive infection, facial swelling, or anaphylaxis features require escalation.
Want more depth?
Read the Deep Dive