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Necrobiosis | |
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Specialty | Pathology |
Necrobiosis is the physiological death of a cell, and can be caused by conditions such as basophilia, erythema, or a tumor. It is identified both with [1] and without necrosis.
Necrobiotic disorders are characterized by presence of necrobiotic granuloma on histopathology. Necrobiotic granuloma is described as aggregation of histiocytes around a central area of altered collagen and elastic fibers. Such a granuloma is typically arranged in a pallisaded pattern. [2]
It is associated with necrobiosis lipoidica and granuloma annulare.
Necrobiosis differs from apoptosis, which kills a damaged cell to protect the body from harm.
Granuloma inguinale is a bacterial disease caused by Klebsiella granulomatis characterized by genital ulcers. It is endemic in many less-developed regions. It is also known as donovanosis, granuloma genitoinguinale, granuloma inguinale tropicum, granuloma venereum, granuloma venereum genitoinguinale, lupoid form of groin ulceration, serpiginous ulceration of the groin, ulcerating granuloma of the pudendum, and ulcerating sclerosing granuloma. Oral manifestations are also notably seen. The lesions of oral cavity are usually secondary to active genital lesions.
A granuloma is an aggregation of macrophages that forms in response to chronic inflammation. This occurs when the immune system attempts to isolate foreign substances that it is otherwise unable to eliminate. Such substances include infectious organisms including bacteria and fungi, as well as other materials such as foreign objects, keratin, and suture fragments.
A dysgerminoma is a type of germ cell tumor; it usually is malignant and usually occurs in the ovary.
Angiomas are benign tumors derived from cells of the vascular or lymphatic vessel walls (endothelium) or derived from cells of the tissues surrounding these vessels.
Tuberculous lymphadenitis is the most common form of tuberculosis infections that appears outside the lungs. Tuberculous lymphadenitis is a chronic, specific granulomatous inflammation of the lymph node with caseation necrosis, caused by infection with Mycobacterium tuberculosis or related bacteria.
Caseous necrosis or caseous degeneration is a unique form of cell death in which the tissue maintains a cheese-like appearance. It is also a distinctive form of coagulative necrosis. The dead tissue appears as a soft and white proteinaceous dead cell mass.
Granulation tissue is new connective tissue and microscopic blood vessels that form on the surfaces of a wound during the healing process. Granulation tissue typically grows from the base of a wound and is able to fill wounds of almost any size. Examples of granulation tissue can be seen in pyogenic granulomas and pulp polyps. Its histological appearance is characterized by proliferation of fibroblasts and new thin-walled, delicate capillaries (angiogenesis), infiltrated inflammatory cells in a loose extracellular matrix.
Calcitriol is the active form of vitamin D, normally made in the kidney. It is also known as 1,25-dihydroxycholecalciferol. It is a hormone which binds to and activates the vitamin D receptor in the nucleus of the cell, which then increases the expression of many genes. Calcitriol increases blood calcium (Ca2+) mainly by increasing the uptake of calcium from the intestines.
In medicine, nodules are small firm lumps, usually greater than 1 cm in diameter. If filled with fluid they are referred to as cysts. Smaller raised soft tissue bumps may be termed papules.
Necrobiosis lipoidica is a necrotising skin condition that usually occurs in patients with diabetes mellitus but can also be associated with rheumatoid arthritis. In the former case it may be called necrobiosis lipoidica diabeticorum (NLD). NLD occurs in approximately 0.3% of the diabetic population, with the majority of sufferers being women.
A pyogenic granuloma or lobular capillary hemangioma is a vascular tumor that occurs on both mucosa and skin, and appears as an overgrowth of tissue due to irritation, physical trauma, or hormonal factors. It is often found to involve the gums, skin, or nasal septum, and has also been found far from the head, such as in the thigh.
Granuloma annulare (GA) is a common, sometimes chronic skin condition which presents as reddish bumps on the skin arranged in a circle or ring. It can initially occur at any age, though two-thirds of patients are under 30 years old, and it is seen most often in children and young adults. Females are two times as likely to have it than males.
A vascular tumor is a tumor of vascular origin; a soft tissue growth that can be either benign or malignant, formed from blood vessels or lymph vessels. Examples of vascular tumors include hemangiomas, lymphangiomas, hemangioendotheliomas, Kaposi's sarcomas, angiosarcomas, and hemangioblastomas. An angioma refers to any type of benign vascular tumor.
Venereology is a branch of medicine that is concerned with the study and treatment of sexually transmitted diseases (STDs). The name derives from Roman goddess Venus, associated with love, beauty and fertility. A physician specializing in venereology is called a venereologist. In many areas of the world, the specialty is usually combined with dermatology.
According to a common point of view epithelioid cells are derivatives of activated macrophages resembling epithelial cells.
Annular elastolytic giant-cell granuloma is a cutaneous condition characterized histologically by a dermal infiltrate of macrophages.
Cock's peculiar tumour is a sebaceous cyst linked growth that can resemble a squamous cell carcinoma. The name is given after a 19th-century English surgeon Edward Cock. The proliferating cyst is usually solitary, but it often arises from a simple trichilemmal cysts in the hair follicle epithelium and these are multiple in 70% of cases. They are most commonly found on the scalp where the proliferating trichilemmal cyst will grow to a large size and ulcerate. Chronic inflammation can cause the cyst to take the form of a granuloma. This granuloma mimics a squamous-cell carcinoma and these ulcerating solitary cysts are called Cock's peculiar tumour.
Epulis is any tumor like enlargement situated on the gingival or alveolar mucosa. The word literally means "(growth) on the gingiva", and describes only the location of the mass and has no further implications on the nature of the lesion. There are three types: fibromatous, ossifying and acanthomatous. The related term parulis refers to a mass of inflamed granulation tissue at the opening of a draining sinus on the alveolus over the root of an infected tooth. Another closely related term is gingival enlargement, which tends to be used where the enlargement is more generalized over the whole gingiva rather than a localized mass.