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, hair, nails, and related muscle and glands. The major function of this system is as a barrier against the external environment.
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.
Bullous pemphigoid is an autoimmune pruritic skin disease preferentially in elderly people, that may involve the formation of blisters (bullae) at the space between the epidermis and dermis skin layers. It is classified as a type II hypersensitivity reaction, with the formation of anti-hemidesmosome antibodies.
Erythema toxicum neonatorum is a common rash in neonates. It appears in up to half of newborns carried to term, usually between day 2–5 after birth; it does not occur outside the neonatal period.
Pruritic urticarial papules and plaques of pregnancy (PUPPP), known in United Kingdom as polymorphic eruption of pregnancy (PEP), is a chronic hives-like rash that strikes some women during pregnancy. Although extremely annoying for its sufferers, it presents no long-term risk for either the mother or unborn child. PUPPP frequently begins on the abdomen and spreads to the legs, feet, arms, chest, and neck.
Insect bites and stings occur when an insect is agitated and seeks to defend itself through its natural defense mechanisms, or when an insect seeks to feed off the bitten person. Some insects inject formic acid, which can cause an immediate skin reaction often resulting in redness and swelling in the injured area. Stings from fire ants, bees, wasps and hornets are usually painful, and may stimulate a dangerous allergic reaction called anaphylaxis for at-risk patients, and some wasps can also have a powerful bite along with a sting. Bites from mosquitoes and fleas are more likely to cause itching than pain.
Pemphigoid diseases are a group of rare autoimmune blistering skin diseases. As its name indicates, pemphigoid is similar in general appearance to pemphigus, but, unlike pemphigus, pemphigoid does not feature acantholysis, a loss of connections between skin cells.
Neonatal-onset multisystem inflammatory disease is a rare genetic periodic fever syndrome which causes uncontrolled inflammation in multiple parts of the body starting in the newborn period. Symptoms include skin rashes, severe arthritis, and chronic meningitis leading to neurologic damage. It is one of the cryopyrin-associated periodic syndromes.
Papular mucinosis is a rare skin disease. Localized and disseminated cases are called papular mucinosis or lichen myxedematosus while generalized, confluent papular forms with sclerosis are called scleromyxedema. Frequently, all three forms are regarded as papular mucinosis. However, some authors restrict it to only mild cases. Another form, acral persistent papular mucinosis is regarded as a separate entity.
Dermatoses of pregnancy are the inflammatory skin diseases that are specific to women while they are pregnant. While some use the term 'polymorphic eruption of pregnancy' to cover these, this term is a synonym used in the UK for Pruritic urticarial papules and plaques of pregnancy, which is the commonest of these skin conditions.
Idiopathic guttate hypomelanosis is a very common acquired disorder that affects women more frequently than men, presenting with skin lesions that occur chiefly on sun exposed regions of the skin, suggesting sun exposure may play a role.
Schamberg's disease, is a chronic discoloration of the skin found in people of all ages, usually affecting the legs. It slowly spreads throughout the body, and is most common in males. It is named after Jay Frank Schamberg, who described it in 1901. There is no known cure for this disease and it is not a life-threatening condition. The skin lesions may cause itching, which can be treated by applying cortisone cream. The cortisone cream will only help with the itching and the discoloration of the skin will remain, which may cause a cosmetic concern in the future. Schamberg's disease is usually asymptomatic meaning that it shows no signs of this condition, except for the discoloration of the skin. This condition is caused by leaky blood vessels, where red blood cells escape near the surface of skin and release iron into the surrounding tissue. The cause of the leaky capillaries is unknown.
Autoimmune progesterone dermatitis may appear as urticarial papules, deep gyrate lesions, papulovesicular lesions, an eczematous eruption, or as targetoid lesions. Autoimmune progesterone dermatitis initially manifests with eye symptoms, e.g. burning, and progresses into rashes. Its relapsing-remitting pattern in women correspond to the progesterone levels during the menstrual cycle, which spike twice a month. It is an extremely rare disease.
Autoimmune estrogen dermatitis presents as a cyclic skin disorder, that may appear eczematous, papular, bullous, or urticarial. with pruritus typically present, skin eruptions that may be chronic but which are exacerbated premenstrually or occur immediately following menses.
Porokeratosis is a specific disorder of keratinization that is characterized histologically by the presence of a cornoid lamella, a thin column of closely stacked, parakeratotic cells extending through the stratum corneum with a thin or absent granular layer.
Cutaneous small-vessel vasculitis, also known as hypersensitivity vasculitis, cutaneous leukocytoclastic vasculitis, hypersensitivity angiitis, cutaneous leukocytoclastic angiitis, cutaneous necrotizing vasculitis and cutaneous necrotizing venulitis, is inflammation of small blood vessels, characterized by palpable purpura. It is the most common vasculitis seen in clinical practice.
Urticarial vasculitis is a skin condition characterized by fixed urticarial lesions that appear histologically as a vasculitis.
Urticarial dermatoses are distinct from urticaria, which examples being drug-induced urticaria, eosinophilic cellulitis and bullous pemphigoid. It is important to distinguish urticaria from urticarial dermatoses. The individual wheals of urticaria are ‘here today and gone tomorrow’, whereas with urticarial dermatoses, the individual lesions last for days or longer.
Urticarial allergic eruption is a cutaneous condition characterized by annular or gyrate urticarial plaques that persist for greater than 24 hours.
IgG4-related skin disease is the recommended name for skin manifestations in IgG4-related disease (IgG4-RD). Multiple different skin manifestations have been described.
