Nevus is a nonspecific medical term for a visible, circumscribed, chronic lesion of the skin or mucosa. The term originates from nævus, which is Latin for "birthmark"; however, a nevus can be either congenital or acquired. Common terms, including mole, birthmark, and beauty mark, are used to describe nevi, but these terms do not distinguish specific types of nevi from one another.
A port-wine stain is a discoloration of the human skin caused by a vascular anomaly. They are so named for their coloration, which is similar in color to port wine, a fortified red wine from Portugal.
Erythema ab igneEAI, also known as hot water bottle rash, is a skin condition caused by long-term exposure to heat. Prolonged thermal radiation exposure to the skin can lead to the development of reticulated erythema, hyperpigmentation, scaling, and telangiectasias in the affected area. Some people may complain of mild itchiness and a burning sensation, but often, unless a change in pigmentation is seen, it can go unnoticed.
Livedo reticularis is a common skin finding consisting of a mottled reticulated vascular pattern that appears as a lace-like purplish discoloration of the skin. The discoloration is caused by reduction in blood flow (ischemia) through the arterioles that supply the cutaneous capillaries, resulting in deoxygenated blood showing as blue discoloration (cyanosis). This can be a secondary effect of a condition that increases a person's risk of forming blood clots (thrombosis), including a wide array of pathological and nonpathological conditions. Examples include hyperlipidemia, microvascular hematological or anemia states, nutritional deficiencies, hyper- and autoimmune diseases, and drugs/toxins.
Adams–Oliver syndrome (AOS) is a rare congenital disorder characterized by defects of the scalp and cranium, transverse defects of the limbs, and mottling of the skin.
Sneddon's syndrome is a form of arteriopathy characterized by several symptoms, including:
A venous lake is a generally solitary, soft, compressible, dark blue to violaceous, 0.2- to 1-cm papule commonly found on sun-exposed surfaces of the vermilion border of the lip, face and ears. Lesions generally occur among the elderly.
Phakomatosis pigmentovascularis is a rare neurocutanous condition where there is coexistence of a capillary malformation with various melanocytic lesions, including dermal melanocytosis, nevus spilus, and nevus of Ota.
Eccrine angiomatous hamartoma (EAH), first described by Lotzbeck in 1859, is a rare benign vascular hamartoma characterized histologically by a proliferation of eccrine and vascular components. EAH exists on a spectrum of cutaneous tumors that include eccrine nevus, mucinous eccrine nevus and EAH. Each diagnostic subtype is characterized by an increase in the number as well as size of mature eccrine glands or ducts, with EAH being distinguished by the added vascular component.
Unilateral nevoid telangiectasia presents with fine thread veins, typically over a segment of skin supplied by a particular nerve on one side of the body. It most frequently involves the trigeminal, C3 and C4, or nearby areas. The condition was named in 1970 by Victor Selmanowitz.
Aplasia cutis congenita is a rare disorder characterized by congenital absence of skin. Ilona J. Frieden classified ACC in 1986 into 9 groups on the basis of location of the lesions and associated congenital anomalies. The scalp is the most commonly involved area with lesser involvement of trunk and extremities. Frieden classified ACC with fetus papyraceus as type 5. This type presents as truncal ACC with symmetrical absence of skin in stellate or butterfly pattern with or without involvement of proximal limbs. It is the most common congenital cicatricial alopecia, and is a congenital focal absence of epidermis with or without evidence of other layers of the skin.
Cobb syndrome is a rare congenital disorder characterized by visible skin lesions and spinal angiomas or arteriovenous malformations (AVMs). The skin lesions of Cobb syndrome typically are present as port wine stains or angiomas, but reports exist of angiokeratomas, angiolipomas, and lymphangioma circumscriptum. The intraspinal lesions may be angiomas or AVMs and occur at levels of the spinal cord corresponding to the affected skin dermatomes. They may in turn produce spinal cord dysfunction and weakness or paralysis.
Blue rubber bleb nevus syndrome is a rare disorder that consists mainly of abnormal blood vessels affecting the skin or internal organs – usually the gastrointestinal tract. The disease is characterized by the presence of fluid-filled blisters (blebs) as visible, circumscribed, chronic lesions (nevi).
Supernumerary nipples–uropathies–Becker's nevus syndrome is a skin condition that may be associated with genitourinary tract abnormalities. Supernumerary nipples, also referred to as polythelia or accessory nipples, is a pigmented lesion of the skin that is present at birth. This pigmentation usually occurs along the milk lines, which are the precursors to breast and nipple development. Clinically, this congenital condition is generally considered benign, but some studies have suggested there may be an association with kidney diseases and cancers of the urogenital system.
Macrocephaly-capillary malformation (M-CM) is a multiple malformation syndrome causing abnormal body and head overgrowth and cutaneous, vascular, neurologic, and limb abnormalities. Though not every patient has all features, commonly found signs include macrocephaly, congenital macrosomia, extensive cutaneous capillary malformation, body asymmetry, polydactyly or syndactyly of the hands and feet, lax joints, doughy skin, variable developmental delay and other neurologic problems such as seizures and low muscle tone.
Cutis marmorata is a benign skin condition which, if persistent, occurs in Cornelia de Lange syndrome, trisomy 13 and trisomy 18 syndromes. When a newborn infant is exposed to low environmental temperatures, an evanescent, lacy, reticulated red and/or blue cutaneous vascular pattern appears over most of the body surface. This vascular change represents an accentuated physiologic vasomotor response that disappears with increasing age, although it is sometimes discernible even in older children. It is also seen in cardiogenic shock.
Diffuse capillary malformation with overgrowth (DCMO) is a subset of capillary malformations (CM) associated with hypertrophy, i.e. increased size of body structures. CM can be considered an umbrella term for various vascular anomalies caused by increased diameter or number of capillary blood vessels. It is commonly referred to as "port-wine stain", and is thought to affect approximately 0.5% of the population. Typically capillaries in the papillary dermis are involved, and this gives rise to pink or violaceous colored lesions. The majority of DCMO lesions are diffuse, reticulated pale-colored stains.
Cutaneous manifestations of COVID-19 are characteristic signs or symptoms of the Coronavirus disease 2019 that occur in the skin. The American Academy of Dermatology reports that skin lesions such as morbilliform, pernio, urticaria, macular erythema, vesicular purpura, papulosquamous purpura and retiform purpura are seen in people with COVID-19. Pernio-like lesions were more common in mild disease while retiform purpura was seen only in critically ill patients. The major dermatologic patterns identified in individuals with COVID-19 are urticarial rash, confluent erythematous/morbilliform rash, papulovesicular exanthem, chilbain-like acral pattern, livedo reticularis and purpuric "vasculitic" pattern. Chilblains and Multisystem inflammatory syndrome in children are also cutaneous manifestations of COVID-19.
