Necrobiosis lipoidica is a necrotising skin condition that usually occurs in patients with

diabetes mellitus Diabetes, also known as diabetes mellitus, is a group of metabolic disorders characterized by a high blood sugar level ( hyperglycemia) over a prolonged period of time. Symptoms often include frequent urination, increased thirst and increased ...

but can also be associated with

rheumatoid arthritis Rheumatoid arthritis (RA) is a long-term autoimmune disorder that primarily affects joints. It typically results in warm, swollen, and painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and hands are invol ...

. 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 patient's shins, often on both legs, although it may also occur on forearms, hands, trunk, and, rarely,

nipple The nipple is a raised region of tissue on the surface of the breast from which, in females, milk leaves the breast through the lactiferous ducts to feed an infant. The milk can flow through the nipple passively or it can be ejected by smooth m ...

penis A penis (plural ''penises'' or ''penes'' () is the primary sexual organ that male animals use to inseminate females (or hermaphrodites) during copulation. Such organs occur in many animals, both vertebrate and invertebrate, but males d ...

, 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 Erythema (from the Greek , meaning red) is redness of the skin or mucous membranes, caused by hyperemia (increased blood flow) in superficial capillaries. It occurs with any skin injury, infection, or inflammation. Examples of erythema not asso ...

) 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. When this happens the patient is at greater risk of developing ulcers. If an injury to the skin occurs on the affected area, it may not heal properly or it will leave a dark scar.

Pathophysiology

Although the exact cause of this condition is not known, it is an inflammatory disorder characterised by collagen degeneration, combined with a granulomatous response. It always involves the dermis diffusely, and sometimes also involves the deeper fat layer. Commonly, dermal blood vessels are thickened (

microangiopathy Microangiopathy (also known as microvascular disease, small vessel disease (SVD) or microvascular dysfunction) is a disease of the microvessels, small blood vessels in the microcirculation. It can be contrasted to coronary heart disease, an angi ...

). It can be precipitated by local trauma, though it often occurs without any injury.

Diagnosis

NL is diagnosed by a skin biopsy, demonstrating superficial and deep perivascular and interstitial mixed inflammatory cell infiltrate (including lymphocytes, plasma cells, mononucleated and multinucleated histiocytes, and eosinophils) in the dermis and subcutis, as well as necrotising vasculitis with adjacent necrobiosis and necrosis of adnexal structures. Areas of necrobiosis are often more extensive and less well defined than in granuloma annulare. Presence of lipid in necrobiotic areas may be demonstrated by Sudan stains. Cholesterol clefts, fibrin, and mucin may also be present in areas of necrobiosis. Depending on the severity of the necrobiosis, certain cell types may be more predominant. When a lesion is in its early stages, neutrophils may be present, whereas in later stages of development lymphocytes and histiocytes may be more predominant.

Treatment

There is no clearly defined cure for necrobiosis.AOCD Website
/ref> NLD may be treated with

PUVA therapy PUVA (psoralen and UVA) is an ultraviolet light therapy treatment for skin diseases: eczema, psoriasis, graft-versus-host disease, vitiligo, mycosis fungoides, large plaque parapsoriasis, and cutaneous T-cell lymphoma, using the sensitizing ef ...

Photodynamic therapy Photodynamic therapy (PDT) is a form of phototherapy involving light and a photosensitizing chemical substance, used in conjunction with molecular oxygen to elicit cell death (phototoxicity). PDT is popularly used in treating acne. It is used cl ...

and improved therapeutic control. Although there are some techniques that can be used to diminish the signs of necrobiosis such as low dose

aspirin Aspirin, also known as acetylsalicylic acid (ASA), is a nonsteroidal anti-inflammatory drug (NSAID) used to reduce pain, fever, and/or inflammation, and as an antithrombotic. Specific inflammatory conditions which aspirin is used to treat inc ...

orally, a steroid cream or injection into the affected area, this process may be effective for only a small percentage of those treated.

References

External links