释义 |
DictionarySeeleukemialymphoblastosis
lymphoblastosis[‚lim·fō‚bla′stō·səs] (medicine) An excessive number of lymphoblasts in peripheral blood; occasionally found in tissues. lymphoblastosis
leukemia [loo-ke´me-ah] a progressive, malignant neoplasm of the blood-forming organs, marked by diffuse replacement of the bone marrow development of leukocytes and their precursors in the blood and bone marrow. It is accompanied by a reduced number of erythrocytes and blood platelets, resulting in anemia and increased susceptibility to infection and hemorrhage. Other typical symptoms include fever, pain in the joints and bones, and swelling of the lymph nodes, spleen, and liver. adj., adj leuke´mic.Types of Leukemia. Leukemia is classified clinically in several ways: (1) acute versus chronic, terms that have become altered from their usual meanings and refer to the degree of cell differentiation; (2) the predominant proliferating cells: myelocytic, granulocytic, or lymphocytic; and (3) increase in or maintenance of the number of abnormal cells in the blood—preleukemic. Acute leukemia is characterized by fatigue, headache, sore throat, and dyspnea, followed by symptoms of acute tonsillitis, stomatitis, bleeding from the mucous membranes of the mouth, alimentary canal, and rectum, and pain in the bones and joints. There eventually is enlargement of the lymph nodes, liver, and spleen. Common to all leukemias are the tendency to bleed and the resultant anemia and increased susceptibility to infection. The diagnosis of leukemia requires confirmation of leukemic cells in the bone marrow by bone marrow biopsy and aspiration. Abnormalities may also be seen in peripheral blood smears.Treatment. The treatment of choice is systemic combination chemotherapy with a variety of antineoplastic drug regimens. The disease can also be treated by a bone marrow transplant after a remission is achieved with chemotherapy.Patient Care. Leukemia affects almost every system within the body and can present a variety of patient care problems. Of primary concern are those symptoms attendant to suppression of normal bone marrow function, particularly susceptibility to infection due to the predominance of immature and abnormally functioning white blood cells, bleeding tendency owing to decreased platelet count, and anemia due to decreased erythrocyte count. Chronic abnormal tissue perfusion, increased need for rest, and decreased sensitivity to heat and cold require careful planning and intervention. Additionally, the patient will need relief from pain and discomfort arising from enlargement of the lymph nodes and distention of the liver and spleen. Because of the malignant nature of leukemia and the fear and anxiety created by the knowledge that one has a form of cancer, patients and their families and significant others will need help in coping with anxiety, mental depression, and realistic fears about dying and death. The financial burden of the illness and disruption of the life of the individual and the family also impose a special burden on them. Referral to appropriate persons and agencies that can help meet their needs is an essential part of the holistic care of the patient with leukemia.acute leukemia leukemia in which the involved cell line shows little or no differentiation, usually consisting of blast cells; two types are distinguished, acute lymphoblastic leukemia and acute myelogenous leukemia.acute granulocytic leukemia acute myelogenous leukemia.acute lymphoblastic leukemia (ALL) (acute lymphocytic leukemia) acute leukemia of the lymphoblastic type, one of the two major categories of acute leukemia, primarily affecting young children. Symptoms include anemia, fatigue, weight loss, easy bruising, thrombocytopenia, granulocytopenia with bacterial infections, bone pain, lymphadenopathy, hepatosplenomegaly, and sometimes spread to the central nervous system (meningism) or to other organs. There are three major subtypes: The pre–B-cell is the most common, consisting of small uniform lymphoblasts that do not synthesize complete functional immunoglobulins" >immunoglobulins or synthesize heavy chains only. The B-cell type is rare and consists of lymphoblasts that express surface immunoglobulins and have a surface translocation similar to that of lymphoma" >Burkitt's lymphoma. The T-cell type has cells that express surface antigens characteristic of T cells.acute megakaryoblastic leukemia (acute megakaryocytic leukemia) a form of acute myelogenous leukemia in which megakaryocytes" >megakaryocytes are predominant and platelets are increased in the blood, often with fibrosis; it can occur at any age. Called also megakaryoblastic or megakaryocytic leukemia.acute monocytic leukemia an uncommon form of acute myelogenous leukemia in which the predominating cells are identified as monocytes" >monocytes; a few myelocytes" >myelocytes may also be present. It can affect any age group. Called also monocytic leukemia.acute myeloblastic leukemia 1. a common kind of acute myelogenous leukemia, in which myeloblasts" >myeloblasts predominate; it usually occurs in infants and middle-aged to older adults. Two types are distinguished; those that have minimal cell differentiation or maturation and those that have more advanced differentiation. Called also myeloblastic leukemia and acute myeloid leukemia.2. acute myelogenous leukemia.acute myelocytic leukemia acute myelogenous leukemia.acute myelogenous leukemia (AML) acute leukemia of the myelogenous type, one of the two major categories of acute leukemia; most types affect primarily middle-aged to elderly people. Symptoms include anemia, fatigue, weight loss, easy bruising, thrombocytopenia, and granulocytopenia that leads to persistent bacterial infections. Several types are distinguished, named according to the stage in which abnormal proliferation begins: acute undifferentiated l., acute myeloblastic l., acute promyelocytic l., acute myelomonocytic l., acute monocytic l., acute erythroleukemia, and acute megakaryocytic l. Called also acute myelocytic l. and acute nonlymphocytic l.acute myeloid leukemia 1. acute myeloblastic leukemia (def. 1).2. acute myelogenous leukemia.acute myelomonocytic leukemia one of the more common types of acute myelogenous leukemia, characterized by both malignant monocytes and myeloblasts; it usually affects middle aged to older adults. See also chronic myelomonocytic leukemia. Called also myelomonocytic or Naegeli's leukemia.acute nonlymphocytic leukemia acute myelogenous leukemia.acute promyelocytic leukemia acute myelogenous leukemia in which more than half the cells are malignant promyelocytes" >promyelocytes, often associated with abnormal bleeding secondary to thrombocytopenia, hypofibrinogenemia, and decreased levels of coagulation factor V; it usually occurs in young adults. Called also promyelocytic leukemia.acute undifferentiated leukemia acute myelogenous leukemia in which the predominating cell is so immature and primitive that it cannot be classified. Called also stem cell leukemia and undifferentiated cell leukemia.adult T-cell leukemia (adult T-cell leukemia/lymphoma) a form of leukemia with onset in adulthood, leukemic cells with T-cell properties, frequent dermal involvement, lymphadenopathy and hepatosplenomegaly, and a subacute or chronic course; it is associated with human T-cell leukemia-lymphoma virus.aleukemic leukemia leukemia in which the leukocyte count is normal or below normal; it may be lymphocytic, monocytic, or myelocytic.basophilic leukemia a rare type of leukemia in which basophils" >basophils predominate; both acute and chronic varieties have been observed.blast cell leukemia acute undifferentiated leukemia.chronic leukemia leukemia in which the involved cell line is well-differentiated, usually lymphocytes" >B-lymphocytes, but immunologically incompetent; types distinguished include chronic granulocytic, chronic lymphocytic, chronic myelomonocytic, eosinophilic, and hairy cell leukemia.chronic granulocytic leukemia chronic leukemia of the myelogenous type, occurring mainly between the age of 25 and 60, usually associated with a unique chromosomal abnormality. The major clinical manifestations of malaise, hepatosplenomegaly, anemia, and leukocytosis are related to abnormal, excessive, unrestrained overgrowth of granulocytes" >granulocytes in the bone marrow. Called also chronic myelocytic or chronic myeloid leukemia.chronic lymphocytic leukemia chronic leukemia of the lymphoblastic type, a common form mainly seen in the elderly; symptoms include lymphadenopathy, fatigue, renal involvement, and pulmonary leukemic infiltrates. Circulating malignant cells are usually differentiated lymphocytes" >B-lymphocytes; a minority of cases have mixed T and B lymphocytes or entirely lymphocytes" >T-lymphocytes.chronic myelocytic leukemia (chronic myelogenous leukemia,) (chronic myeloid leukemia) chronic granulocytic leukemia.chronic myelomonocytic leukemia a slowly progressing form of chronic leukemia that usually affects the elderly and sometimes progresses to acute myelomonocytic leukemia. Symptoms include splenomegaly, monocytosis with granulocytosis, and thrombocytopenia.leukemia cu´tis leukemia with leukocytic invasion of the skin marked by pink, reddish brown, or purple macules, papules, and tumors.eosinophilic leukemia a form of leukemia in which the eosinophil" >eosinophil is the predominating cell. Although resembling chronic granulocytic leukemia in many ways, this form may follow an acute course despite the absence of predominantly blast forms in the peripheral blood.granulocytic leukemia myelogenous leukemia.hairy cell leukemia a form of chronic leukemia marked by splenomegaly and by an abundance of abnormal large mononuclear cells covered by hairlike villi (hairy cells) in the bone marrow, spleen, liver, and peripheral blood. Called also leukemic reticuloendotheliosis.leukopenic leukemia aleukemic leukemia.lymphatic leukemia (lymphoblastic leukemia) leukemia associated with hyperplasia and overactivity of the lymphoid tissue; there are increased numbers of circulating malignant lymphocytes and lymphoblasts. See also acute lymphoblastic leukemia and chronic lymphocytic leukemia.lymphocytic leukemia (lymphogenous leukemia) (lymphoid leukemia) lymphoblastic leukemia.lymphosarcoma cell leukemia the B-cell type of acute lymphoblastic leukemia.mast cell leukemia a rare type marked by overwhelming numbers of tissue mast cells in the peripheral blood.megakaryoblastic leukemia acute megakaryocytic leukemia.megakaryocytic leukemia 1. hemorrhagic thrombocythemia.2. acute megakaryocytic leukemia.micromyeloblastic leukemia a form of myelogenous leukemia in which the immature, nucleoli-containing cells are small and are distinguishable from lymphocytes only by special staining.monocytic leukemia acute monocytic leukemia.myeloblastic leukemia 1. myelogenous leukemia.2. acute myeloblastic leukemia.myelocytic leukemia (myelogenous leukemia) (myeloid granulocytic leukemia) a form arising from myeloid tissue in which leukocytes" >polymorphonuclear leukocytes and their precursors predominate.myelomonocytic leukemia (Naegeli's leukemia) acute myelomonocytic leukemia.plasma cell leukemia (plasmacytic leukemia) a rare type in which the predominating cell in the peripheral blood is the plasma cell; it is often seen in asociation with multiple myeloma" >multiple myeloma.prolymphocytic leukemia a type of chronic leukemia marked by large numbers of circulating lymphocytes, predominantly prolymphocytes, with massive splenomegaly and occasionally lymphadenopathy; prognosis is often poor.promyelocytic leukemia acute promyelocytic leukemia.Rieder cell leukemia a form of acute myelogenous leukemia in which the blood contains the abnormal cells called lymphocytes" >Rieder's lymphocytes, asynchronously developed lymphocytes that have immature cytoplasm and a lobulated, indented, comparatively more mature nucleus.stem cell leukemia acute undifferentiated leukemia.subleukemic leukemia aleukemic leukemia.undifferentiated leukemia acute undifferentiated leukemia.lym·pho·blas·to·sis (lim'fō-blas-tō'sis), The presence of lymphoblasts in the peripheral blood; sometimes used as a synonym for acute lymphocytic leukemia. [lymphoblast + G. -osis, condition] lymphoblastosis (1) Acute lymphocytic leukaemia, see there. (2) Blast crisis, see there. (3) A nonspecific term for the presence of lymphoblasts in the peripheral circulation.lym·pho·blas·to·sis (lim'fō-blas-tō'sis) The presence of lymphoblasts in the peripheral blood; sometimes used as a synonym for acute lymphocytic leukemia. [lymphoblast + G. -osis, condition]lymphoblastosis An excessive number of primitive lymphocytes (lymphoblasts) in the blood and, occasionally, in the tissues, as in acute lymphoblastic LEUKAEMIA. |