Hello and welcome to HCM, Red fluid filled intensely itchy lesions can be due to infective as well as non-infective lesions. Infective lesions include scabies. Scabies is am infectious process caused by a itch mite called sarcoptius scabei. This mite lodges itself in the skin and makes burrows. The mte lays eggs in these burrows which are intensely itchy. Diagnosis of scabies can be made on clinical examination and identification of the mite in the burrows. These burrows are most frequent in between the fingers, shoulders, back, although any part of the body may be affected. The other possibility is that of blistering disorder called bullous pemphegoid, dermatitis herpetiformis. These are two possibilities of the long list. However, clinical examination is mandatory for diagnosis. The condition can be managed only after diagnosis is made. Thanks and take are Dr Shailja P Wahal