What is the reason for the small blisters?

Folliculitis

folliculitis is caused by bacterial, fungal infection of hair follicles and surrounding tissue inflammation, because inflammatory stimulation can lead to small blisters on the foreskin, accompanied by pain, redness and other symptoms.

2, herpes

patients foreskin infected with human herpes virus herpes, due to virus damage local tissue blisters, usually blisters liquid is infectious.

3, eczema

If the patient foreskin contact allergens eczema, serious illness can be caused by abnormal skin immune response small blisters.