Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.3.1.107 (DAT)
 1,471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have examined IgG and complement factor C3d deposition on erythrocytes by means of the direct Coombs' test (DAT) and looked for an association with the anaemia seen in falciparum malaria in children living in an area of hyperendemic malaria transmission (in Ghana). In one study (in 1997), 53 out of 199 patients had a positive DAT. Of these, 45 samples reacted with anti-C3d antibodies, 2 with anti-IgG and 6 with both reagents. There were significantly lower haemoglobin (Hb)-levels and higher prevalence of spleen enlargement in DAT-positive than in DAT-negative patients. Hb-levels were independently associated with DAT and age. This initial study was designed to investigate the role of intravascular haemolysis (IVH), but we found no association between IVH and either DAT result or anaemia. Because of the risk of selection bias we repeated the study using consecutive enrollment of malaria patients and were able to confirm the results in a total of 49 DAT-positive and 183 DAT-negative patients. This second study (in 1998) was designed to look at the importance of erythrophagocytosis through measurement of plasma neopterin levels and total nitrite and nitrate as markers of NO-release. Both parameters were significantly higher in DAT-positive than in DAT-negative patients (P < 0.001), indicating that complement binding to erythrocytes was associated with macrophage activation. Plasma levels of haptoglobin, interleukin-10 and tumour necrosis factor-alpha did not vary between the groups. The studies support the role of complement activation and erythrophagocytosis in the pathogenesis of anaemia in falciparum malaria in African children.
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PMID:Complement binding to erythrocytes is associated with macrophage activation and reduced haemoglobin in Plasmodium falciparum malaria. 1170 71

A hemolytic transfusion reaction due to anti-Fy3 is reported in an African American patient with no history of sickle cell disease. This 82-year-old African American woman received two units of RBCs for anemia (Hab 7 g/dL) on admission for a left hip fracture. On hospital Day 7, the patient underwent left hip endoprosthesis surgery; she received two units of RBCs on the second postoperative day due to Hb of 6.1 g/dL. Her urine was dark during surgery and postoperatively. Her posttransfusion plasma was red. Her Hb dropped from 8.4 to 6.4 g/dL over 24 hours after the transfusion. Her total bilirubin rose to 4.0 mg/dL, with and LDH value of 1558 U/L and a haptoglobin of 10.9 mg/dL. Both the antibody detection test and the DAT were positive. An anti-Fy3 was identified in the serum and in the eluate. To the best of our knowledge, this is the first case of acute intravascular hemolysis due to anti-Fy3 in a patient without sickle cell disease.
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PMID:Acute hemolytic transfusion reaction secondary to anti-Fy3. 1598 43

The erythrocyte lifespan in haemolytic anemia is shortened while erythropoesis is increased. Important labaratory findings are increased reticulocytes, LDH, indirect bilirubin and a decreased haptoglobin level. The most important diagnostic tool for further work up of hemolytic anemia is the direct antiglobulin test (DAT, Coombs test) to differentiate autoimmune hemolytic anemia (AIHA) from other causes. Another important group are fragmentation syndroms (hemolytic uremic syndrome and thrombotic thrombocytopenic purpura). In these forms of haemolytic anemia fragmented red blood cells can be found in the blood smear together with thrombocytopenia. A severe problem in paroxysmal nocturnal hematuria is the incidence of thrombosis. The following review describes the most important forms of hemolytic anemia in the adult and the diagnostic and therapeutic strategies.
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PMID:[Hemolytic anemias in adults]. 2204 36

Referral to hematology for anemia is common. In paroxysmal nocturnal hemoglobinuria (PNH), cells deficient in the glycosylphosphatidyl inositol (GPI) anchor are lysed by complement. Eculizumab improves overall survival and quality of life while reducing hemolysis, transfusion requirements, and thrombosis. We evaluated the frequency of screening for PNH in patients with unexplained anemia. Key clinical features, laboratory data, and investigations were recorded for patients referred for anemia since 2010, without a specific cause found. PNH testing was done by flow cytometry. 540 patients had: anemia not yet diagnosed (NYD, n=318 (including unexplained iron deficiency, n=92; DAT-negative hemolysis, n=9)); anemia of chronic disease, n=173; and pancytopenia NYD, n=49. 82.4% had LDH testing done; 85.0% total bilirubin; 78.7% reticulocyte counts; and 40.6% haptoglobin level; 131 (24.2%) had possible hemolysis. PNH testing was done in 56 (10.4%). Those screened for PNH were more likely to have: younger age (P=0.04); a history of thrombosis (P<0.001); undergone a BMBx (P<0.001); received RBC transfusions (P=0.0018); or evidence of DAT-negative hemolysis (P<0.001). In summary, PNH was tested for in a minority of patients with unexplained anemia (10.4%) despite potential indicators of hemolysis in 24.2%. Increased screening could identify patients who would benefit from treatment and should be considered.
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PMID:Frequency of and reasons for paroxysmal nocturnal haemoglobinuria screening in patients with unexplained anaemia. 2913 83