What is the cause of a small bump under the eyelid?

A small bump under the eyelid may be due to folliculitis, blepharitis, blepharospasm cysts and other causes.
1. Folliculitis: a small bump under the eyelid may be folliculitis, often due to staphylococcal infection caused by the eyelid follicles appear purulent inflammation. The patient will have a small bump under the eyelid, accompanied by itching, redness and swelling and other symptoms.
2. Blepharitis: Blepharitis is an acute purulent inflammation of the eyelid glands, caused by a bacterial infection that results in localized inflammation of the eye. It is mainly manifested as localized abscesses around the eyelids, and as the disease progresses, small pimple-like abscesses may appear.
3. Blepharophalangeal cysts: Blepharophalangeal cysts may be caused by the blockage of the outlet of the blepharophalangeal gland, causing the gland’s secretions to be retained in the eyelid, and the patient will appear to have a small pimple under the eyelid, which is usually painless.
When patients experience discomfort such as small bumps growing under the eyelids, they should consult a doctor in time, under the guidance of a specialized doctor, to make a clear diagnosis and give intervention treatment if necessary.