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Tuberculoid Leprosy
Tuberculoid leprosy is a form of leprosy characterized by solitary skin lesions that are asymmetrically distributed with few lesions and well demarcated edges. There is also early and marked nerve damage. It tends to heal spontaneously. Tuberculoid leprosy is characterized by the formation of epithelioid cell granulomas with a large number of epithelioid cells. In this form of leprosy ''Mycobacterium leprae'' are either absent from the lesion or occur in very small numbers. This type of leprosy is the most benign and the least contagious. See also * Leprosy * 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 th ... References External links Bacterium-related cutaneous conditions {{Cutaneous-infection-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leprosy
Leprosy, also known as Hansen's disease (HD), is a long-term infection by the bacteria ''Mycobacterium leprae'' or ''Mycobacterium lepromatosis''. Infection can lead to damage of the nerves, respiratory tract, skin, and eyes. This nerve damage may result in a lack of ability to feel pain, which can lead to the loss of parts of a person's extremities from repeated injuries or infection through unnoticed wounds. An infected person may also experience muscle weakness and poor eyesight. Leprosy symptoms may begin within one year, but, for some people, symptoms may take 20 years or more to occur. Leprosy is spread between people, although extensive contact is necessary. Leprosy has a low pathogenicity, and 95% of people who contract ''M. leprae'' do not develop the disease. Spread is thought to occur through a cough or contact with fluid from the nose of a person infected by leprosy. Genetic factors and immune function play a role in how easily a person catches the disease. Lepro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 resul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epithelioid Cell
According to a common point of view epithelioid cells (also called epithelioid histiocytes) are derivatives of activated macrophages resembling epithelial cells. Structure and function Structurally, epithelioid cells (when examined by light microscopy after stained with hematoxylin and eosin), are elongated, with finely granular, pale eosinophilic (pink) cytoplasm, and central, ovoid nuclei (oval or elongate), which are less dense than that of a lymphocyte. They have indistinct shape and often appear to merge into one another, forming aggregates known as giant cells. When examined by transmission electron microscopy in epithelioid cells in the field of Golgi lamellar complex are taped not only zonated, but also sleek vesicles with dense center, and also great many (more than 100) large granulas with diameters up to 340 nm and with finegranular matrix more light than in macrophage granulas, sometimes with perigranular halo. “The most prominent feature of these cells is the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granuloma
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. Definition In pathology, a granuloma is an organized collection of macrophages. In medical practice, doctors occasionally use the term ''granuloma'' in its more literal meaning: "a small nodule". Since a small nodule can represent any tissue from a harmless nevus to a malignant tumor, this use of the term is not very specific. Examples of this use of the term ''granuloma'' are the lesions known as vocal cord granuloma (known as contact granuloma), pyogenic granuloma, and intubation granuloma, all of which are examples of granulation tissue, not granulomas. "Pulmonary hyalinizing granuloma" is a lesion characterized ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycobacterium Leprae
''Mycobacterium leprae'' (also known as the leprosy bacillus or Hansen's bacillus), is one of the two species of bacteria that cause Hansen’s disease (leprosy), a chronic but curable infectious disease that damages the peripheral nerves and targets the skin, eyes, nose, and muscles. It is an acid-fast, Gram-positive, rod shaped bacterium and an obligate intracellular parasite, which means, unlike its relative ''Mycobacterium tuberculosis'', it cannot be grown in cell-free laboratory media. This is likely due to gene deletion and decay that the genome of the species has experienced via reductive evolution, which has caused the bacterium to depend heavily on its host for nutrients and metabolic intermediates. It has a narrow host range and apart from humans, the only other natural hosts are nine-banded armadillo and red squirrels. The bacteria infect mainly macrophages and Schwann cells, and are typically found congregated as a palisade. ''Mycobacterium leprae'' was sensi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leprosy
Leprosy, also known as Hansen's disease (HD), is a long-term infection by the bacteria ''Mycobacterium leprae'' or ''Mycobacterium lepromatosis''. Infection can lead to damage of the nerves, respiratory tract, skin, and eyes. This nerve damage may result in a lack of ability to feel pain, which can lead to the loss of parts of a person's extremities from repeated injuries or infection through unnoticed wounds. An infected person may also experience muscle weakness and poor eyesight. Leprosy symptoms may begin within one year, but, for some people, symptoms may take 20 years or more to occur. Leprosy is spread between people, although extensive contact is necessary. Leprosy has a low pathogenicity, and 95% of people who contract ''M. leprae'' do not develop the disease. Spread is thought to occur through a cough or contact with fluid from the nose of a person infected by leprosy. Genetic factors and immune function play a role in how easily a person catches the disease. Lepro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 resul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
