What causes a raised black birthmark with rough surface and hair growth, and what should be done about it?

Under normal circumstances, a raised black birthmark with rough surface and hair growth may be caused by excessive friction, genetics, neurofibroma, pigmented hairy epidermal nevus, folliculitis, or other factors. If abnormalities occur, timely medical consultation is recommended. Specific analyses are as follows:

1. Excessive Friction

Wearing poorly made or ill-fitting clothing for prolonged periods may lead to excessive friction on the birthmark area, causing local redness, swelling, sensory abnormalities, and possibly stimulating hair growth. It is recommended to wear comfortable, soft clothing and avoid tight garments.

2. Genetics

If one or both parents have similar conditions, their children may have an increased risk of developing black birthmarks. These birthmarks may gradually become raised and rough-surfaced with hair growth as the child grows. If they affect appearance, surgical removal may be considered.

3. Neurofibroma

Neurofibromatosis is caused by genetic mutations leading to abnormal proliferation of nerve tissue and tumor formation. These tumors may lie beneath the skin, causing raised, rough skin surfaces with possible hair growth, and may be accompanied by neurological abnormalities or skeletal deformities. Small neurofibromas may not require treatment but should be monitored regularly; larger or symptomatic ones may require surgical excision.

4. Pigmented Hairy Epidermal Nevus

This is a type of cutaneous connective tissue nevus, which may feature varying numbers of short black hairs and localized elevations due to smooth muscle hyperplasia in hair follicles. This nevus usually causes no discomfort but may affect appearance. Surgical excision is generally recommended by physicians.

5. Folliculitis

If hair follicles within the birthmark area become inflamed, folliculitis may develop. This condition can cause surface irregularities on the birthmark, along with increased hair growth, redness, and swelling. Anti-inflammatory and anti-infective treatments such as fusidic acid sodium ointment, clarithromycin granules, or levofloxacin tablets may be used under medical guidance.

It is recommended to maintain a balanced diet, consume more fresh fruits and vegetables, and supplement essential micronutrients such as vitamins. Personal hygiene should be maintained, and comfortable, breathable clothing should be worn.