What are blood filled cysts?

[Guide]

"Blood-filled pimples are most commonly caused by a condition called cystic acne. Cystic acne occurs when facial hair follicles become clogged and fill with blood and pus, says Proactiv. The hormone androgen, which increases during the teen years, contributes to the formation of cystic acne, explains WebMD.....Cystic acne happens when a bacterial infection occurs deep in the skin. The infection causes large, red, painful bumps or nodules to form deep under the surface of the skin. The outermost layer of the nodule is filled with blood, with a layer of pus underneath. Cystic acne is hereditary and is most common in young men, although women get it as well, notes WebMD. Never attempt to pop blood-filled pimples caused by cystic acne, advises Proactiv. If the pimples are popped, the bacterial infection may spread to the rest of the face, causing further breakouts." reference.com

According to Proactive, "Cystic acne, or any form of scarring acne, needs immediate attention by a dermatologist. A doctor will have the best solution for nodular acne treatment." The better part of wisdom would be to go back to your dermatologist and ask your questions about this. 

"Blood filled pimples should never be popped or squeezed and instead should be allowed to heal naturally. Opening the pimple before it has healed can spread bacteria to other areas of the skin, which can cause infection." Livestrong

Nurse Bridgid has an interesting article, Is that a Zit, Cyst, or Furuncle??, about cysts which you might find helpful. 

Health Central has others asking the same question, but you have to login to get the answers.

Papule, Pustule, Pimple, Comedo, Lesion, Cyst & Abscess Explained