Panniculitis is a group of diseases whose hallmark is inflammation of subcutaneous adipose tissue. Symptoms include tender skin nodules, and systemic signs such as weight loss and fatigue.
The dermis or corium is a layer of skin between the epidermis and subcutaneous tissues, that primarily consists of dense irregular connective tissue and cushions the body from stress and strain. It is divided into two layers, the superficial area adjacent to the epidermis called the papillary region and a deep thicker area known as the reticular dermis. The dermis is tightly connected to the epidermis through a basement membrane. Structural components of the dermis are collagen, elastic fibers, and extrafibrillar matrix. It also contains mechanoreceptors that provide the sense of touch and thermoreceptors that provide the sense of heat. In addition, hair follicles, sweat glands, sebaceous glands, apocrine glands, lymphatic vessels, nerves and blood vessels are present in the dermis. Those blood vessels provide nourishment and waste removal for both dermal and epidermal cells.
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.
Cutis laxa or pachydermatocele is a group of rare connective tissue disorders in which the skin becomes inelastic and hangs loosely in folds.
The human skin is the outer covering of the body and is the largest organ of the integumentary system. The skin has up to seven layers of ectodermal tissue and guards the underlying muscles, bones, ligaments and internal organs. Human skin is similar to most of the other mammals' skin, and it is very similar to pig skin. Though nearly all human skin is covered with hair follicles, it can appear hairless. There are two general types of skin, hairy and glabrous skin (hairless). The adjective cutaneous literally means "of the skin".
Blue nevus is a type of melanocytic nevus. The blue colour is caused by the pigment being deeper in the skin than in ordinary nevi. In principle they are harmless but they can sometimes be mimicked by malignant lesions, i.e. some melanomas can look like a blue nevus.
Cutis verticis gyrata is a medical condition usually associated with thickening of the scalp. People show visible folds, ridges or creases on the surface of the top of the scalp. The number of folds can vary from two to roughly ten and are typically soft and spongy. These folds cannot be corrected with pressure. The condition typically affects the central and rear regions of the scalp, but sometimes can involve the entire scalp.
Lipodermatosclerosis is a skin and connective tissue disease. It is a form of lower extremity panniculitis, an inflammation of the layer of fat under the epidermis.
Elastosis perforans serpiginosa is a unique perforating disorder characterized by transepidermal elimination of elastic fibers and distinctive clinical lesions, which are serpiginous in distribution and can be associated with specific diseases.
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.
Juvenile hyaline fibromatosis is a very rare, autosomal recessive disease due to mutations in capillary morphogenesis protein-2. It occurs from early childhood to adulthood, and presents as slow-growing, pearly white or skin-colored dermal or subcutaneous papules or nodules on the face, scalp, and back, which may be confused clinically with neurofibromatosis. The World Health Organization, 2020, reclassified the papules and nodules that occur in juvenile hyaline firbromatosis as one of the specific benign types of tumors in the category of fibroblastic and myofibroblastic tumors.
Acrokeratoelastoidosis of Costa is a familial condition characterized by multiple keratotic papules on the dorsum of the hands and feet, palms, soles, in which electron microscopy shows rarified, abnormal elastic tissue.
Nevus sebaceus or sebaceous nevus is a congenital, hairless plaque that typically occurs on the face or scalp. Such nevi are classified as epidermal nevi and can be present at birth, or early childhood, and affect males and females of all races equally. The condition is named for an overgrowth of sebaceous glands, a relatively uncommon hamartoma, in the area of the nevus. NSJ is first described by Josef Jadassohn in 1895.
Photoaging or photoageing is a term used for the characteristic changes to skin induced by chronic UVA and UVB exposure. Tretinoin is the best studied retinoid in the treatment of photoaging.
Paraneoplastic acrokeratosis, or Bazex syndrome is a cutaneous condition characterized by psoriasiform changes of hands, feet, ears, and nose, with involvement of the nails and periungual tissues being characteristic and indistinguishable from psoriatic nails. The condition is associated with carcinomas of the upper aerodigestive tract.
Primary cutaneous marginal zone lymphomas represent a heterogeneous group of diseases characterized by solitary or multiple dermal or subcutaneous nodules. Lymphomas included in this group are:
Spiradenoma, also spiroma or eccrine spiradenoma, is a cutaneous condition that is typically characterized, clinically, as a solitary, deep-seated dermal nodule around 1 cm, occurring on the ventral surface of the body. Spiradenoma lesions are benign sudoriferous tumors, and have also been described as cystic epitheliomas of the sweat glands.
Poikiloderma vasculare atrophicans (PVA), is a cutaneous condition characterized by hypo- or hyperpigmentation, telangiectasia and skin atrophy. Other names for the condition include prereticulotic poikiloderma and atrophic parapsoriasis. The condition was first described by pioneer American pediatrician Abraham Jacobi in 1906. PVA causes areas of affected skin to appear speckled red and inflamed, yellowish and/or brown, gray or grayish-black, with scaling and a thinness that may be described as "cigarette paper". On the surface of the skin, these areas may range in size from small patches, to plaques, to neoplasms.
Melanoma with features of a Spitz nevus is a cutaneous condition characterized histologically with tissue similar to a spitz nevus and with overall symmetry and a dermal nodule of epithelioid melanocytes that do not mature with progressively deeper dermal extension.
