Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002874 (aplastic anemia)
 5,905 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We measured the endogenous plasma concentration of thrombopoietin (TPO) in 76 patients with acquired aplastic anaemia (AA) by a sensitive sandwich enzyme-linked immunosorbent assay (ELISA). The plasma TPO concentrations were significantly higher in AA patients when compared to healthy control subjects (P < 0.0001) and there was a significant negative correlation between plasma TPO concentrations and platelet counts in 54 AA patients who had not received any platelet transfusions prior to sampling. On the other hand, there was no statistically significant correlation between the TPO concentrations and platelet counts in 22 AA patients who had previously received platelet transfusions. We studied serial changes of plasma TPO concentration in 24 patients who showed an increase in their platelet counts following bone marrow transplantation or immunosuppressive (IS) therapy. Although a decrease in plasma TPO concentration was observed, levels remained above the range of normal healthy controls even in the patients who attained normal platelet counts following therapy. A decrease in TPO concentrations was observed in only half of the responders to IS therapy. Whether exogenous TPO will result in increased platelet counts in AA patients with high TPO levels remains to be determined.
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PMID:Measurement of endogenous plasma thrombopoietin in patients with acquired aplastic anaemia by a sensitive enzyme-linked immunosorbent assay. 920 95

In an attempt to evaluate the role of thrombopoietin (TPO) in the pathobiology of aplastic anaemia (AA), we have examined TPO levels in sera from 54 AA patients and 119 healthy controls. A total of 92 samples were collected from AA patients: 43 samples were harvested at diagnosis, 23 samples in the cytopenic period after treatment, and 26 samples when patients were in partial (n=10) or complete remission (n=16) following immunosuppressive treatment. TPO serum levels were assessed by a sandwich-antibody ELISA that utilized a polyclonal rabbit antiserum for both capture and signal. Serum samples from normal donors revealed a mean TPO level of 95.3 +/- 54.0 pg/ml (standard deviation). Mean TPO levels in AA sera collected at diagnosis and before onset of treatment were 2728 +/- 1074 pg/ml (P<0.001 compared to normal controls: mean platelet count at that time: 27x10(9)/l). TPO serum levels of AA patients in partial or complete remission after immunosuppressive treatment were significantly lower than TPO levels at diagnosis (P<0.001). However, despite normal platelet counts (mean 167x10(9)/l), TPO levels remained significantly elevated in complete remission (mean TPO 1009 +/- 590 pg/ml, P<0.001 compared to normal controls). There was a significant inverse correlation between serum TPO levels and platelet counts in AA patients who were not transfused for at least 2 weeks prior to sample collection (coefficient of correlation (r) = -0.70, P<0.0001). In summary, TPO levels were highly elevated in sera of patients with AA. Thus there is no evidence to suggest an impaired TPO response contributing to thrombocytopenia in AA. Thrombopoietin did not return to normal levels in remission, indicating a persisting haemopoietic defect in remission of AA. We hypothesize that elevated levels of TPO may be required to maintain normal or near normal platelet counts in remission of AA.
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PMID:Thrombopoietin serum levels in patients with aplastic anaemia: correlation with platelet count and persistent elevation in remission. 950 43