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L
Lentigo:
A small brownish spot (of the pigment melanin) on the skin.
Lentigo maligna melanoma:
A melanoma characterized by small brownish spots on the skin. Lentigo maligna melanoma occurs in about 5% of malignant melanoma cases, usually in the elderly. It is most common in sun damaged skin on the head, neck, and arms.
Also see: Melanoma
Lesion:
An injury or wound, a localized abnormal structural change in the skin.
Lichen Planus:
Lichen planus is an inflammatory disease of the skin, mucous membranes, hair follicles, and nails. It appears as reddish-purple flat topped bumps with white lines (WickhamÕs striae) on the skin. The bumps can appear anywhere on the body, but are usually seen on the wrist, ankles, thighs, and shins. The rash may cause severe itching. KoebnerÕs phenomenon may be present where lesions appear along lines of trauma or injury.
Oral lesions appear as reticulate white lesions on the buccal mucosa, tongue, gums, and lips. Most lesions occur on the inside of the cheeks. Lichen planus of the scalp is called lichen planopilaris and is very rare. It causes redness and irritation to hair follicles and can cause permanent hair loss. Lichen planus of the nails is more common in children and causes longitudinal riding, splitting, and thinning of the nails.
A specific cause is not known for lichen planus. Most researchers believe it is an autoimmune disease. Some cases of lichen planus like reactions have been linked to allergies of medications and Hepatitis C.
There is no known cure for lichen planus. Treatment is aimed at relieving itching and improving the appearance of lesions. Topical steroid creams are used and generally help relieve itching. For severe cases, oral steroids, antihistamines, phototherapy, or retinoid therapy may be initiated. Most cases will clear within one year, but some may last for several years.
Submitted by: Nitra H. Cole, MSN, ARNP, NP-C
Lichen Nitidus:
Lichen nitidus is a chronic inflammatory disease with no known cause. It appears as small, flat-topped, discrete, uniform bumps, usually in clusters. It is most common on the trunk and arms. KoebnerÕs phenomenon may be present where lesions appear along lines of trauma or injury. Other than mild itching, lichen nitidus usually has no symptoms. It is most common in children and young adults. Treatment is not necessary for lichen nitidus. Topical steroids may be used to relieve itching. Lesions may remain for months to years and will resolve spontaneously.
Submitted by: Nitra H. Cole, MSN, ARNP, NP-C
Lipoatrophy:
Loss of fat from underneath the skin. Common causes are aging and disease.
Liver spots:
"Age spots" or "liver spots" are flat, brown areas called lentigines. They have nothing to do with the liver - they are caused by the sun and usually appear on the face, hands, back and feet. They are generally harmless. They may look like melanoma and therefore may require evaluation. Commercial "fade" creams will not make lentigines disappear, but effective prescription medications and surgical resurfacing treatments are available.
Lupus:
Patients with lupus erythematosus (LE) often have skin signs and develop many different types of lesions. LE skin diseases are divided into two broad categories: those skin lesions that occur only in people with LE, known as LE-specific skin lesions, and those skin lesions that can occur in people with LE, but can also occur in other diseases (LE-non-specific skin lesions). There are three broad categories of LE-specific skin lesions: chronic cutaneous LE (CCLE), or diseases limited to the skin, subacute cutaneous LE (SCLE), and acute cutaneous LE (ACLE). Another skin condition related to lupus is discoid LE, where unsightly red scaly patches develop which leave white scars. Discoid LE predominantly affects the cheeks and nose, but sometimes involves the upper back, V of neck, and backs of hands. Bald areas can develop if the hair follicles are involved. Discoid LE may affect the lips causing ulcers and scaling.