Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.5.4.4 (adenosine deaminase)
 5,136 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Red-cell adenosine deaminase (ADA) activity in children with Diamond-Blackfan anaemia is significantly increased (1.91 +/- 0.90 U/g Hb) compared to that seen in transient erythroblastopenia of childhood (0.80 +/- 0.16 U/g Hb) or normal individuals (0.61 +/- 0.13 U/g). These data thus further support that measurement of this purine metabolic enzyme is useful in diagnosing the cause of pure RBC aplasia in children. Of interest, however, elevated RBC-ADA activity also is seen in some children with acute leukaemia and other haematologic disorders. In children with acute lymphoblastic leukaemia (ALL), the increase in RBC-ADA activity is proportional to the degree of anaemia. However, the elevated RBC-ADA activity in this leukaemic population is not related to the fetal haemoglobin concentration. These data suggest increased RBC-ADA activity may be a non-specific manifestation of abnormal erythroid stem cell function, an alteration distinct from that seen with reactivation of fetal erythropoiesis. However, since almost all patients with Diamond-Blackfan anaemia manifest elevated RBC-ADA activity, this chemical alteration yet may reflect the specific erythroid differentiation lesion in this disorder.
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PMID:Elevated red cell adenosine deaminase activity: a marker of disordered erythropoiesis in Diamond-Blackfan anaemia and other haematologic diseases. 334 76

It previously has been reported that red blood cells (RBC) of patients with Diamond-Blackfan syndrome (DBS) have increased activity of orotidine decarboxylase (ODC) and adenosine deaminase (ADA). The studies reported here compared the activity of these two enzymes in DBS erythrocytes, cord blood, and reticulocytes. The activity of ODC, although increased in some DBS erythrocytes, was not significantly different from that seen in cord RBC or reticulocytes. In contrast, RBC-ADA activity was increased in 23 of 26 DBS patients; and this enzyme elevation was distinct from that seen in cord blood and reticulocytes. Moreover, ADA activity was normal in 26 of 27 patients with transient erythroblastopenia of childhood (TEC). Taken together, these data indicate RBC-ADA activity is more sensitive than ODC as a marker of DBS. In addition, RBC-ADA activity continues to be useful for distinguishing DBS and TEC in most patients with RBC hypoplasia.
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PMID:Comparative activity of erythrocyte adenosine deaminase and orotidine decarboxylase in Diamond-Blackfan anemia. 375 68

Abnormalities of adenosine deaminase, a critical enzyme of the purine salvage pathway, have been reported in association with immune dysfunction, acute leukemia, and hereditary hemolytic anemia. We report data showing that erythrocyte adenosine deaminase activity is also abnormal in congenital hypoplastic anemia (the Diamond-Blackfan syndrome). Adenosine deaminase activity in erythrocytes from 12 patients (mean +/- S.D., 2.20 +/- 0.77 IU per gram of hemoglobin) was substantially greater than that observed in 50 controls (0.62 +/- 0.13 IU per gram). Enzyme activity in affected patients was also greater than that seen in cord blood or in erythrocytes from patients with hemolytic anemia, acquired aplastic anemia, Fanconi's hypoplastic anemia, acquired pure red-cell aplasia, or transient erythroblastopenia of childhood. These observations indicate that erythrocyte adenosine deaminase activity may be a unique marker for identifying congenital hypoplastic anemia.
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PMID:Elevated erythrocyte adenosine deaminase activity in congenital hypoplastic anemia. 664 73