Page 6 - DermPath Correlation

H Simplex if grouped.
4. If there are Blisters or vesicles The mnemonic is ICI(Imperial Chemical
Industries) Inflammatory including Immunological, Contact dermatitis and Infective.

Inflammatory causes can include drugs but remember Immunological causes in the elderly
particularly bullous pemphigoid. Contact dermatitis usually gives smaller vesicles rather than
blisters but individual vesicles can join up into blisters. If blisters are linear and itchy it is probably a
Plant contact dermatitis. Infective blisters are usually bullous impetigo due to a staph infection. If in
a dermatomal distribution blisters are likely to be Herpes Zoster.

5. If Skin Coloured and Scaly The mnemonic is ( I am coming Don't go away) Ichthyosis,
Acanthosis nigricans, Confluent and Reticulate papillomatosis, Dariers, Grovers and Acrokeratosis
verruciformis) but these are mostly uncommon conditions.

6. Skin coloured and Non scaly No good mnemonic except ICS (Infiltrates of cells or
substances) Most cases are Infiltrates of cells or substances eg Granuloma annulare,
Sarcoidosis, Mucinosis, Scleromyxedema, Scleredema, Scleroderma, Metastases,
I also like to look at a slide and immediately state whether I think this is an Epidermal or a
Dermal histological pattern. I then assign a couple of mnemonics as follows

If Epidermal then the diagnosis will be one of the Red Scaly or Skin Coloured scaly
diagnoses and the mnemonic will be the PMsPET a little cat called PETAL

If Dermal then the mnemonic will be CUL DVA EVIE

If Pustules obvious us II and if vesicles or blisters use ICI (See explanation for these
mnemonics below.)

So look at the slide, look for features and patterns, decide whether Epidermal or Dermal or
Both, Go through the diseases in the relevant mnemonic and then look for Specific
histological features, patterns or clues to decide on the likeliest diagnosis. If you need more
information on a histopath feature look in the posts opposite and for patterns
see DermatopathologyMadeSimple. If you want to see clinical pictures of the skin diseases
go to GlobalSkin Atlas. If you need more information on the mnemonics look at Differential
Diagnosis

Part 7:
Red Non scaly Diseases

2. If it is red but not scaly consider Cellulitis, Urticaria, Lupus, Light eruption, Drug reaction, Viral
exanthem or Annular erythema .The mnemonic is C U L at the Department