Keloid is a scar that appears usually at the site of skin damaged by acne, burns, cuts, chicken pox, insect bites, piercing or tattoo. It surfaces like a hypertrophic scar, but expands outside the wound margins and generally builds over time as the skin heals from its damage. Keloids are benign (non-cancerous) and fibrous skin tumours.
The cells in the skin may produce excessive amounts of collagen with keloid scars and the collagen fibres are also thick and wavy. This makes the appearance of keloids thick and raised causing psychological distress to the victim. Bigger scars may interfere with daily activities and in some rare a keloid may become cancerous. Keloids are more common in people with darker skin and they may appear because of genetic skin disorders or presence of high number of fibroblasts in the skin.
The commonest presentation of Alopecia Areata is appearance of bald patches on the scalp. In most cases, hair falls out in small, round patches about the size of a small coin. The patient may have single or multiple such patches. In some cases these patches may remain static, whereas in some cases the patches may spread to involve larger areas of the scalp. In some cases, hair loss is more extensive. Although it is not very common, the disease can progress to cause total loss of hair on the head (Alopecia Areatatotalis) or complete loss of hair on the head, face, and rest of the body