|
Dermatosis Papulosa Nigra
Dermatosis papulosa nigra (DPN) is a condition of many small, benign skin lesions on the face, a condition generally presenting on dark-skinned individuals. DPN is extremely common, affecting up to 30% of Black people in the US.Grimes PE, Arora S, Minus HR, Kenney JA Jr. Dermatosis papulosa nigra. Cutis. Oct 1983;32(4):385-6, 392. From a histological perspective, DPN resembles seborrheic keratoses. The condition may be cosmetically undesirable to some. Despite its great frequency, DPN was firstly described and named only in 1925 by Italian tropicalist doctor Aldo Castellani. They should not be confused for Leser-Trélat sign, a sudden explosion of lesions due to a growing tumor. Pathophysiology The pathophysiology of DPN is unknown. Evidence of family history may suggest a genetic propensity. Treatment DPN lesions are benign and no treatment generally is indicated unless lesions are cosmetically undesirable. Surgical options including curettage, cryotherapy and laser therapy ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Skin Lesion
A skin condition, also known as cutaneous condition, is any medical condition that affects the integumentary system—the organ system that encloses the body and includes skin, nails, and related muscle and glands. The major function of this system is as a barrier against the external environment. Conditions of the human integumentary system constitute a broad spectrum of diseases, also known as dermatoses, as well as many nonpathologic states (like, in certain circumstances, melanonychia and racquet nails). While only a small number of skin diseases account for most visits to the physician, thousands of skin conditions have been described. Classification of these conditions often presents many nosological challenges, since underlying causes and pathogenetics are often not known. Therefore, most current textbooks present a classification based on location (for example, conditions of the mucous membrane), morphology ( chronic blistering conditions), cause ( skin conditions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Seborrheic Keratoses
A seborrheic keratosis is a non-cancerous (benign) skin tumour that originates from cells, namely keratinocytes, in the outer layer of the skin called the epidermis. Like liver spots, seborrheic keratoses are seen more often as people age. The tumours (also called lesions) appear in various colours, from light tan to black. They are round or oval, feel flat or slightly elevated, like the scab from a healing wound, and range in size from very small to more than across. They are often associated with other skin conditions, including basal cell carcinoma. Sometimes, seborrheic keratosis and basal cell carcinoma occur at the same location. At clinical examination, a differential diagnosis considers warts and melanomas. Because only the top layers of the epidermis are involved, seborrheic keratoses are often described as having a "pasted-on" appearance. Some dermatologists refer to seborrheic keratoses as "seborrheic warts", because they resemble warts, but strictly speaking, the ter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Aldo Castellani
Aldo Luigi Mario Castellani, Marchese di Chisimajo, KCMG (8 September 1874 – 3 October 1971) was an Italian pathologist and bacteriologist. He is best remembered as discoverer of the etiology of sleeping sickness (with David Bruce, 1903) and Yaws (1905), as a pioneer in the development and use of combined vaccines. Life and achievements Castellani was born in Florence and educated there, qualifying in medicine in 1899. He worked for a time in Bonn and joined the School of Hygiene and Tropical Medicine in London in 1901. As bacteriologist with the Royal Society Commission on Sleeping Sickness in 1902, he went to Entebbe, Uganda with George Carmichael Low and Cuthbert Christy. He demonstrated the cause and means of transmission of sleeping sickness, discovered the spirochete of yaws, and did other original work in bacteriology and in parasitic diseases of the skin. In 1903 he was appointed Bacteriologist to the Government of Ceylon at the Central laboratory in Colombo an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Keloid
Keloid, also known as keloid disorder and keloidal scar, is the formation of a type of scar which, depending on its maturity, is composed mainly of either type III (early) or type I (late) collagen. It is a result of an overgrowth of granulation tissue (collagen type III) at the site of a healed skin injury, which is then slowly replaced by collagen type I. Keloids are firm, rubbery lesions or shiny, fibrous nodules, and can vary from pink to the color of the person's skin or red to dark brown. A keloid scar is benign and not contagious, but sometimes accompanied by severe itchiness, pain, and changes in texture. In severe cases, it can affect the movement of the skin. In the United States, keloid scars are seen 15 times more frequently in people of sub-Saharan African descent than in people of European descent. There is a higher tendency to develop a keloid among those with a family history of keloids and people between the ages of 10 and 30 years. Keloids should not be confused ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
List Of Cutaneous Conditions
Many skin conditions affect the human integumentary system—the organ system covering the entire surface of the Human body, body and composed of Human skin, skin, hair, Nail (anatomy), nails, and related muscle and glands. The major function of this system is as a barrier against the external environment. The skin weighs an average of four kilograms, covers an area of two square metres, and is made of three distinct layers: the epidermis (skin), epidermis, dermis, and subcutaneous tissue. The two main types of human skin are: glabrous skin, the hairless skin on the palms and soles (also referred to as the "palmoplantar" surfaces), and hair-bearing skin.Burns, Tony; ''et al''. (2006) ''Rook's Textbook of Dermatology CD-ROM''. Wiley-Blackwell. . Within the latter type, the hairs occur in structures called pilosebaceous units, each with hair follicle, sebaceous gland, and associated arrector pili muscle. Embryology, In the embryo, the epidermis, hair, and glands form from the ectod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
