Rash
Infectious
Autoimmune
Drugs
Malignancy (melanoma, hypopigmented mycosis fungoides)
Nutrition
Pellagra (vit B3 (niacin))
viral
Bacterial
Dengue/ Zika/ Chikugunya
RSMF
Fungal
HSV/ HIV / VZV
Lyme
tinea versicolour
tinea corporis/capitis
measles
Coxsackie A
salmonella typhi
Staph aureus
strep throat
SLE
dermatomyositis
Derm
dry skin (age/menopausal)
- congenital vs acquired
- distribution (localized/generalised, Sun exposure)
- colour
- non melanocyte ddx / systemic syndromes
Parasitic
Scabies
Candida (+satellite lesions)
Metabolic
Uremia
Thyroid
Liver disease
Trauma to skin (post-inflammatory hypopigmentation/hyperpigmentation)
Deposition
Agyria (silver)
Stasis dermatitis (CVI)
DM dermopathy
Macular amyloidosis
Capillaritis (haemosiderin)
Ecthyma (deep impetigo)
Lichen sclerosis
Vasculitis (painful, burning, post-inflammatory hyperpigmentation)
Primary skin lesion
Derm conditions (eczema/folliculitis/heat rash (papular)
- TRO melanoma or mycosis fungoides
- reactive perforating collagenosis (familial OR acquired)
Secondary skin lesion
Prurigo nodularis
Lichen simplex chronicus