Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038002 (splenomegaly)
 9,873 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Refractoriness is a complication of multiple platelet transfusions in 30-70% of patients with bone marrow failure. The major causes are HLA alloimmunisation and non-immune platelet consumption; the latter is usually found in patients with DIC, septicaemia or splenomegaly. Initial management of alloimmunised patients who are refractory to platelet transfusions from random donors is the use of HLA-matched platelet donors; this results in improved responses to platelet transfusions in about 65% of these patients. Platelet crossmatching may reveal the presence of platelet-specific antibodies in some patients who are refractory to platelet transfusions from HLA-matched donors and may assist in the selection of compatible platelet donors. The identification of compatible donors is not possible in all refractory patients; alternative approaches such as plasma exchange and high dose intravenous gammaglobulin have been used in such patients with variable results. Insights into the mechanism of HLA alloimmunisation have suggested methods for its prevention. Primary HLA alloimmunisation is dependent on the presence in transfusions of contaminating cells bearing HLA class II antigens; pure platelet concentrates are non-immunogenic as platelets only express HLA class I antigens. Studies using leucocyte-poor blood components for multitransfused patients have demonstrated a reduction in HLA alloimmunisation from about 50-20% and a decrease in the incidence of refractoriness. Improvements in the techniques for leucocyte depletion of red cell and platelet concentrates and the possibility of inactivation of the HLA class II antigen-bearing cells by UV irradiation might make prevention of alloimmunisation an attainable goal in the near future.
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PMID:Platelet transfusions: the problem of refractoriness. 218 45

The authors have studied the case of a female patient with rheumatoid polyarthritis, who developed a lymphocytic proliferation in the blood, the marrow, and the liver, associated with a neutropenia. Several similar cases have been recently reported in the literature. The cellular proliferation is made of large granulous lymphocytes and the study of membrane markers enables to find the following homogeneous phenotype: E rosette+, CD8+, HNK-1+, FcR+, CD4-luminal diameter "divided by degrees - -, IgS-, HLA class II-. This lymphocytic sub-population produces little interleukin-2, responds weakly to mitogens (PHA, CON A, PWM), and inhibits the response of normal lymphocytes to the same mitogens. These lymphocytes have a weak natural killer activity but, on the contrary, develop a very strong cytotoxic activity which is antibody-dependent. Clinically, splenomegaly, anemia and infections are frequent and hepatomegaly or thrombopenia more rare. Adenopathies are never present. The evolution is chronic in nature and not very aggressive, although the lymphocytic proliferation is monoclonal in origin, as demonstrated in molecular biology studies. The neutropenia might be secondary to an inhibiting effect of lymphocytes on the granular precursors of the bone marrow. There is a definite association between this lympho-proliferative syndrome and rheumatoid polyarthritis, and this association appears to be different from the Felty's syndrome.
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PMID:[Characterization of chronic lymphocytic proliferation in a female patient having rheumatoid polyarthritis with neutropenia]. 361 55