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What is Necrobiosis lipoidica and explain in detail?
Necrobiosis lipoidica is a necrotising skin condition that usually occurs in patients with diabetes mellitus but can also be associated with rheumatoid arthritis. In the former case it may be called necrobiosis lipoidica diabeticorum (NLD). NLD occurs in approximately 0.3% of the diabetic population, with the majority of those affected are women (approximately 3:1 females to males affected).
The severity or control of diabetes in an individual does not affect who will or will not get NLD. Better maintenance of diabetes after being diagnosed with NLD will not change how quickly the NLD will resolve.

Signs and symptoms
NL/NLD most frequently appears on the patients shins, often on both legs, although it may also occur on forearms, hands, trunk, and, rarely, nipple, penis, and surgical sites. The lesions are often asymptomatic but may become tender and ulcerate when injured. The first symptom of NL is often a "bruised" appearance (erythema) that is not necessarily associated with a known injury. The extent to which NL is inherited is unknown.
NLD appears as a hardened, raised area of the skin. The center of the affected area usually has a yellowish tint while the area surrounding it is a dark pink. It is possible for the affected area to spread or turn into an open sore