Hard bumps under the skin on the body may be caused by acne, keloids, dermatofibromas, subcutaneous lipomas, or other diseases.
1. Acne: Higher sebum secretion, blockage of hair follicle openings, and Propionibacterium acnes infection form open or closed pimples, resulting in hard bumps under the skin.
2. Keloid: keloid is a benign tumor of the skin, the cause of which has not been fully clarified, may be genetic defects, resulting in abnormal cell proliferation, generally after trauma, local skin formation of hyperplastic hard swelling.
3. Dermatofibroma: Dermatofibroma usually occurs in the limbs, such as arms, legs, is a benign tumor caused by proliferation of dermal fibroblasts, resulting in the appearance of local round, hard, reddish-brown or dark brown nodules.
4. Subcutaneous lipoma: Subcutaneous lipoma is a benign tumor that originates from subcutaneous adipose tissue, which is composed of mature adipose tissue. The lumps caused by lipoma are slightly elastic and can be deformed by pressure.
In addition to this, epidermal cysts, folliculitis, boils, can also cause hard bumps on the skin. It is recommended to go to the hospital for examination and targeted treatment with the doctor’s advice.