Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pure red cell aplasia (PRCA) is a rare hematological disease characterized by selective marrow erythroid aplasia. We report the clinical features and treatment results of 16 Chinese patients with PRCA. Nine (56%) cases were not associated with any underlying disorders and were considered idiopathic, while seven patients (44%) had associated diseases, three involving the thymus, two with T large granular lymphocyte leukemia (T-LGLL), and one each with Stevens-Johnson syndrome and acute hepatitis A. Conventional-dose corticosteroid therapy resulted in complete remission in three of 13 patients. Cyclosporin A was used in six patients. There were three complete and one partial remissions. High-dose methylprednisolone was ineffective in four patients who failed conventional-dose corticosteroids but achieved complete remission in one patient with thymoma who did not respond to thymectomy. Antithymocyte globulin was used in four patients, resulting in partial remission in only one patient with concomitant T-LGLL. Intravenous gamma globulin and danazol were ineffective in three patients. Thymectomy was performed in two patients, with one patient remitting. This is the largest series of PRCA reported in an oriental population. Our results indicate that treatment of PRCA may still be problematic and better therapeutic strategy will have to be defined.
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PMID:Pure red cell aplasia: clinical features and treatment results in 16 cases. 876 55

There is evidence indicating that autoreactive B cells constitute a substantial part of the B cell repertoire. This autoreactive repertoire secretes the so-called natural autoantibodies characterized by their broad reactivity mainly directed against well-conserved public epitopes. Their germinal origin is suggested by their early appearance during ontogeny, their expression of cross-reactive idiotopes, and structural studies of their sequence. As for the physiological role of the repertoire, it may play a major role as a first barrier of defense. It is presently unknown whether these polyreactive B cells could constitute a pre-immune template which, through an antigen-driven process, may be involved in the production of immune high-affinity antibodies. This autoreactive B cell repertoire frequently undergoes malignant transformation, although there is controversy concerning the reasons accounting for this. It has been postulated that the continuous challenge of this autoreactive repertoire by self-antigens could create propitious conditions for malignant transformation to occur. However, this hypothesis still needs to be substantiated. Chronic lymphocytic leukemia (CLL), the most frequent form of leukemia in western countries, is characterized by constant expression of the CD5 marker and low expression of surface membrane immunoglobulin (Ig) in B lymphocytes. CLL B lymphocyte is frequently committed for natural autoantibody secretion. Despite expressing the Epstein-Barr virus (EBV) receptor CLL B cells cannot be infected by the EBV virus, they overexpress the bcl-2 protein and they are unable to adequately respond when stimulated through the B cell receptor pathway. Autoimmune-associated phenomena are frequently observed in B-cell CLL. These autotoxic manifestations are mainly directed against hematopoietic cells. In most cases, autoantibodies against red blood cells are warm reactive polyclonal IgG. Immune thrombocytopenia is observed in about 2% of cases, but higher frequencies of increased platelet associated Igs have been reported. Pure red cell aplasia and autoantibodies against neutrophils are only rarely observed. This pattern is similar to that observed in primary immunodeficiency syndromes, in which immune thrombocytopenia, autoimmune hemolytic anemia, and pure red cell aplasia are frequently observed. The potential role of T cell defects in inducing autoimmune complications in B-cell CLL has been stressed by recent publications showing increased frequency of autoimmune hemolytic anemia in patients treated with purine nucleoside analogues. However, evidence is presently scarce concerning a functional impairment of T cells after administration of these drugs.
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PMID:Basic biology of autoimmune phenomena in chronic lymphocytic leukemia. 948 25

Interferon-alpha has been shown to improve survival in patients with chronic granulocytic leukaemia, therefore it is increasingly becoming part of the standard treatment of this condition. Interferon has a wide variety of side-effects. Pure red cell aplasia has been reported in a few cases of chronic granulocytic leukaemia but this usually heralds the onset of the transformation to the acute phase. This paper reports a possible, and not previously reported, side-effect of interferon-alpha in a patient with chronic granulocytic leukaemia.
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PMID:Pure red cell aplasia in a patient with chronic granulocytic leukaemia treated with interferon-alpha. 1076 6

Large granular lymphocyte leukemia (LGL L) has been morphologically characterized as a group of lymphoproliferative diseases that include T-cell large granular lymphocytic leukemia (T-LGL L) and chronic lymphoproliferative disorders of natural killer cells (CLPD-NK). We investigated mutations in the Src homology 2 (SH2) domain of the signal transducer and activator of transcription 3 (STAT3) gene in Asian cohorts of T-LGL L and CLPD-NK (n = 42 and 11, respectively). Two mutations, Y640F and D661Y, were identified using direct sequencing or allele-specific (AS) PCR. Y640F and D661Y mutations were found in seven and 18 patients, respectively. Two patients were positive for both mutations. Frequencies of STAT3 mutations in T-LGL L and CLPD-NK were 47.6% and 27.2%, respectively. Pure red cell aplasia (PRCA) was associated with the mutations (P = 0.005). The mutations were persistently found at stable levels in some patients after more than 5 years using AS-quantitative PCR. The results of the present study indicate that the SH2 domain of the STAT3 gene is frequently mutated in Asian T-LGL L and CLPD-NK, and that PRCA is closely correlated with the mutations.
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PMID:STAT3 gene mutations and their association with pure red cell aplasia in large granular lymphocyte leukemia. 2435 Aug 96

Pure red cell aplasia is a rare cause of anemia, caused by an absence of red blood cell precursors in the bone marrow. It is usually a paraneoplastic syndrome, associated most commonly with large-cell granular lymphocyte leukemia but also thymoma. For patients who present both pure red cell aplasia and thymoma, thymectomy leads to an initial remission of the aplasia in 30% of cases. However, sustained remission may require the addition of medications such as corticosteroids, cyclosporine, or cyclophosphamide. We present a case of pure red cell aplasia associated with a thymoma in an otherwise healthy 80 year-old woman.
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PMID:Pure red cell aplasia and associated thymoma. 2476 63

Pure red cell aplasia (PRCA) is a type of bone marrow failure syndrome (stem cell failure) and is characterized by severe normocytic, normochromic anemia associated with reticulocytopenia and the absence of erythroblasts in otherwise normal bone marrow. The acquired form of chronic PRCA may present as a primary hematological disease in the absence of any other diseases or secondary to thymoma, lymphoproliferative disorders, infections and collagen vascular diseases or after exposure to various drugs or chemicals. Thus, identifying the cause of PRCA is crucial for the optimal management of this disorder. Idiopathic PRCA and secondary PRCA refractory to treatment of the underlying diseases are both generally treated as an immune-mediated disorder. Most chronic PRCA patients successfully treated with immunosuppressants require maintenance immunosuppressive therapy. Refractoriness to induction immunosuppressive therapy and relapse of anemia may be risk factors for death in idiopathic, thymoma-associated and large granular lymphocyte leukemia-associated PRCA. The major causes of death are infections and organ failure. Standard treatment options for refractory and relapsed PRCA patients and the immunopathophysiology of acquired chronic PRCA merit further research.
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PMID:[Progress in the clinical management of pure red cell aplasia and future prospects]. 2693 27

Pure red cell aplasia (PRCA) is a syndrome defined by a normocytic normochromic anemia with severe reticulocytopenia and marked reduction or absence of erythroid precursors from the bone marrow. Diamond-Blackfan anemia is a congenital form of PRCA. Acquired PRCA may be either a primary disorder or secondary to some other disorder or agent. Primary acquired PRCA is an autoimmune disorder that is frequently antibody-mediated. Myelodysplastic syndromes may also present with the morphologic appearance of PRCA. Secondary acquired PRCA may be associated with collagen vascular/autoimmune disorders such as systemic lupus erythematosus; lymphoproliferative disorders such as chronic lymphocytic leukemia or large granular lymphocyte leukemia; infections, particularly B19 parvovirus; thymoma and other solid tumors; or a variety of other disorders, drugs, or toxic agents. The therapeutic approach to PRCA typically involves immunosuppression, but specific pathogenic subtypes are associated with specific therapeutic approaches. Cyclosporine A, with or without concurrent corticosteroids, appears to be the single most effective immunosuppressive agent.
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PMID:Pure red cell aplasia. 2788 71

Pure red cell aplasia (PRCA) is a syndrome defined by a normocytic normochromic anemia with severe reticulocytopenia and marked reduction or absence of erythroid precursors from the bone marrow. Diamond-Blackfan anemia is a congenital form of PRCA. Acquired PRCA may be either a primary disorder or secondary to some other disorder or agent. Primary acquired PRCA is an autoimmune disorder that is frequently antibody-mediated. Myelodysplastic syndromes may also present with the morphologic appearance of PRCA. Secondary acquired PRCA may be associated with collagen vascular/autoimmune disorders such as systemic lupus erythematosus; lymphoproliferative disorders such as chronic lymphocytic leukemia or large granular lymphocyte leukemia; infections, particularly B19 parvovirus; thymoma and other solid tumors; or a variety of other disorders, drugs, or toxic agents. The therapeutic approach to PRCA typically involves immunosuppression, but specific pathogenic subtypes are associated with specific therapeutic approaches. Cyclosporine A, with or without concurrent corticosteroids, appears to be the single most effective immunosuppressive agent.
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PMID:Pure red cell aplasia. 2791 62