General approach to rashes
Contents
Background
Dermatology Nomenclature
Small lesions (<0.5cm)
Name | Raised/Palpable | Fluid-Filled | Other Description | Diagram |
Macule | No | None | flat, cirumscribed, colored | ![]() |
Papule | Yes | None | Solid | ![]() |
Vesicle | Yes | Clear | ![]() | |
Pustule | Yes | Pus | Leukocytes or keratin | ![]() |
Large lesions (>0.5cm)
Other
Differential Diagnosis
Rash
- Acute generalized exanthematous pustulosis
- Allergic reaction
- Aphthous stomatitis
- Atopic dermatitis
- Chickenpox
- Chikungunya
- Coxsackie
- Dermatitis herpetiformis
- Erysipelas
- Exfoliative erythroderma
- Impetigo
- Measles
- Miliaria (Heat Rash)
- Necrotizing fasciitis
- Pellagra
- Poison Oak, Ivy, Sumac
- Psoriasis
- Pityriasis rosea
- Scabies
- Seborrheic dermatitis
- Serum Sickness
- Smallpox
- Shingles
- Tinea capitus
- Tinea corporis
- Vitiligo
Rash visual diagnosis
Poison ivy/Oak/Sumac
Poison ivy/Oak/Sumac
Psoriasis before and after treatment.