Listeria infection, also known as listeriosis, is a serious foodborne illness caused by the bacterium Listeria monocytogenes. It most commonly spreads through contaminated food, such as unpasteurized dairy products, ready-to-eat meats, and improperly washed raw vegetables. While many healthy people may experience mild symptoms or none at all, listeria infection can be severe and life-threatening for certain groups. Pregnant women, …

Liposarcoma is a rare type of cancer that develops in fat cells deep within the body. Unlike a lipoma, which is benign, liposarcoma is malignant and can grow aggressively. It most often occurs in the abdomen, thighs, buttocks, or behind the knee, but it can develop in almost any area where fat tissue is present. Liposarcoma tends to grow slowly …

A lipoma is a slow-growing, noncancerous lump of fatty tissue that usually develops just beneath the skin. Lipomas are soft to the touch, move easily when pressed, and are generally painless. They can appear anywhere on the body but are most common on the neck, shoulders, back, arms, thighs, and abdomen. Lipomas are usually harmless and do not require treatment …

Lip cancer is a type of oral cancer that develops on the lips, most often on the lower lip. It usually begins as a small sore, lump, or discolored patch that does not heal over time. Lip cancer is commonly classified as a type of squamous cell carcinoma, which arises from the thin, flat cells lining the lips. Because the …

Neurodermatitis, also known as lichen simplex chronicus, is a chronic skin condition characterized by persistent itching and thickened, leathery skin. It develops as a result of repeated scratching or rubbing of the skin, which worsens irritation and creates an ongoing itch-scratch cycle. Neurodermatitis is not contagious and commonly affects areas such as the neck, scalp, wrists, forearms, ankles, and genital …

Lichen sclerosus is a long-term inflammatory skin condition that most commonly affects the genital and anal areas. It causes the skin to become thin, white, and fragile, which can lead to discomfort and scarring over time. Although it can occur at any age, lichen sclerosus is most often seen in postmenopausal women and, less commonly, in children and men. The …

Oral lichen planus is a chronic inflammatory condition that affects the mucous membranes inside the mouth. It is considered an immune-mediated disorder and may present with periods of flare-ups and remission. Oral lichen planus is not contagious, but it can cause persistent discomfort and requires long-term monitoring due to potential complications. Symptoms Symptoms of oral lichen planus vary depending on …

Lichen planus is an inflammatory condition that can affect the skin, mouth, nails, scalp, and genital areas. It often appears as purplish, flat-topped bumps on the skin or as white, lacy patches inside the mouth. The condition is not contagious and can affect adults of any age, though it is most common in middle-aged adults. The exact course of lichen …

Lice are tiny parasitic insects that live on the scalp and hair and feed on small amounts of blood from the scalp. Head lice are the most common type and mainly affect children, especially those in close-contact settings such as schools and daycare centers. Lice infestations are not a sign of poor hygiene and can affect anyone. Lice spread easily …

Leukoplakia is a condition in which thick, white or gray patches develop on the inside of the mouth. These patches cannot be scraped off and most commonly appear on the tongue, gums, inner cheeks, or the floor of the mouth. Leukoplakia itself is usually not dangerous, but it can sometimes be an early sign of cancer. The condition is often …