Blistering = Please note the three "D"s - Development, Duration, Distribution (± itch)
| Generalised | |
|---|---|
| Eczema | Lichenification, crusting itching |
| Dermatitis herpetiformis | Itching, extensor surfaces, persisting, superficial blisters Coeliac disease. Linear deposits of IgA along basement membrane. Px - Dapsone, sulphapyridine, no gluten. |
| Chickenpox | Prodromal illness. Crops blisters, self limiting. May affect mucous membranes |
| Pityriasis lichenoides | Similar to chickenpox but no infective agent. May last for months |
| Erythema multiforme | Deep blisters in target lesions. Mucous membranes. Drugs/bugs |
| Pemphigoid | Older patients. Trunk & flexures. Preceding erythema then deep tense blisters. Ab in dermo-epidermal junction. May cause scarring. Remits after months of PO steroids. |
| Pemphigus | Adults. Widespread superficial blisters. Mucous membrane erosions. Chronic. Nikolsky’s sign. High morbidity despite steroids & azathioprine. |
| Localised | |
|---|---|
| Eczema | Pompholyx blisters on hands & feet, itching |
| Allergic Rxn | Include insect bites & topical applications |
| Psoriasis | Deep sterile non-itching blisters on soles & palms |
| Impetigo | Usually localised, Staph & Strep isolated |
| Herpes simplex | Itching lesions develop turbid blisters |