Vesicular Diseases

Vesicles are small clear fluid filled deep seated lesions in the epidermis. They are a feature of eczema/ dermatitis when acute in onset but can also be seen in delayed type hypersensitivity reactions such as a reaction to tinea on the soles of the feet. They are usually itchy and can subsequently become pustular from secondary bacterial infection. If you have pustules enquire if they were clear fluid filled lesions initially. If they were pustules initially then consider pustular psoriasis.  

The development of herpes simplex superimposed on a background atopic eczema is always a diagnostic problem but look for a sudden painful deterioration in the condition particularly with painful lesions appearing around the eyes.

So the mnemonic for vesicles is the same as for Blisters ie ICI (Infective , Contact dermatitis and Inflammatory and Immunological.)

Infective vesicles - Viral - herpes simplex  and Zoster, Chickenpox, (Varicella) , hand foot and mouth, Covid, Orf, 

                               Bacterial - Bullous impetigo, Blistering distal dactylitis

                               Fungal -  Vesicular tinea soles of feet

                               Syphilis - Malignant type in HIV

                               Rickettsia - Rickettsial pox

The other causes of Contact, Inflammatory and Immunological vesicles are best looked at in the Blistering section.

Contact - Allergic and irritant dermatitis, Atopic and Discoid eczemas , Pompholyx eczema , 

Inflammatory - Drugs, PCT , Miliaria, Arthropod bite particularly fire ants, Jellyfish stings , Hailey Hailey and Dariers 

Immunological - Bullous pemphigoid, Dermatitis herpetiformis, Linear IgA disease, EB Acquisita, Rarely pemphigus (usually crusts), Bullous lupus erythematosus

Rare Genetic - Kindler Syndrome - trauma-induced skin blistering (mostly on the hands and feet) starting in infancy, skin photosensitivity that improves after childhood, and progressive poikiloderma (a combination of skin thinning, color changes, and tiny blood vessels) Consider inherited EB variants in neonatal vesicles and Incontinentia pigmenti .



View this discussion of dermatitis in DermNet NZ