Visceral leishmaniasis and Coombs' positive hemolytic anemia: a rare association in an infant treated with liposomal amphotericin B.
(25/208)
Visceral leishmaniasis is a worldwide, disseminated intracellular protozoal infection that usually manifests by fever, hepatosplenomegaly, anemia, thrombocytopenia, leukopenia and hypergammaglobulinemia. Although anemia is a usual finding, Coombs' positive hemolytic anemia has rarely been reported in association with this disease. Pentavalent antimonials have been the preferred treatment for this disease for decades, but increasing numbers of treatment failure with antimony are being reported. Liposomal amphotericin B is a new drug which is highly efficacious in the treatment of visceral leishmaniasis and produces minimal toxicity. Here we report an infant with visceral leishmaniasis associated with Coombs' positive hemolytic anemia who was successfully treated with liposomal amphotericin B. (+info)
Extraction of a monospecific Coombs-reagent from chicken eggs.
(26/208)
During the last ten years the extraction of specific antibodies (ab) from the yolk of eggs of immunised chickens is more and more accepted as an useful alternative to the immunisation of mammals. The subject of this work is the immunisation of chickens with human IgG and the extraction of specific anti human IgG ab from egg yolk in order to obtain monospecific Coombs reagent. 12 Leghorn hens (25 weeks old) were immunised with intact human IgG (INTACGLOBIN). The chickens were immunised with 100 microg IgG/animal once per week for a period of seven weeks. The highest titre was observed after the 5th immunisation, the following immunisations achieved no further titre increase. The IgY purification was performed according to the method of Akita and Nakai (1993). The resulting IgY preparation was tested for the presence of hetero-agglutinine by means of direct agglutination using human erythrocytes of all blood groups. Thereafter 58 blood donors were tested by means of direct or indirect Coombs-test using a reference reagent (DAKO) and a Coombs reagent isolated from chicken eggs (IgY antibodies). No differences have been found between the results obtained using both Coombs reagents. Presented results show that there is a possibility to produce Coombs-reagent in chickens. Advantages of this method are: 1) non invasive antibody sampling by egg collection instead of bleeding the animal (refinement of antibody production); 2) decreasing amount of animals necessary to produce high amounts of reagent; 3) IgY-preparation contains no hetero-agglutinine in contrast to serum ab from mammals, therefore additional step in reagent production e.g. the absorption of hetero-agglutinins is not necessary. (+info)
Idiopathic non-syphilitic paroxysmal cold haemoglobinuria in children.
(27/208)
Three examples of non-syphilitic paroxysmal cold haemoglobinuria (PCH) in children are described which occurred, within a period of 16 days, in association with a febrile illness. No definite viral aetiology or obvious epidemiological association could be established. A Donath-Landsteiner antibody of anti-P specificity was demonstrated in all three patients. The serological aspects of PCH are critically discussed. (+info)
Acquired chronic pure red cell aplasia successfully treated with intravenous pulse methylprednisolone therapy.
(28/208)
A 65-year-old male patient developed acquired chronic pure red cell aplasia (PRCA) associated with hypergammaglobulinemia and positive Coombs' test during the treatment of eosinophilic pneumonia with prednisolone (PSL). His PRCA was treated with oral PSL at a dose of 60 mg/day for 3 weeks, but anemia further progressed. Immediately after high-dose intravenous pulse methylprednisolone therapy (1 g/day for 3 days) however, reticulocyte crisis occurred and his anemia rapidly improved. He has been in complete remission under a maintenance dose of PSL for more than 2 years. This patient indicates that high-dose intravenous methylprednisolone therapy is one of the useful treatments, not only for constitutional PRCA, but also for acquired chronic PRCA. (+info)
Investigation of the mechanism of drug-induced autoimmune hemolytic anemia in cynomolgus monkeys elicited by a repeated-dose of a humanized monoclonal antibody drug.
(29/208)
We investigated the mechanism of hemolytic anemia detected in a repeated-dose toxicity study using cynomolgus monkeys that were treated with a humanized antibody drug. This drug was an IgG1 monoclonal antibody (MoAb) that binds to the human HM1.24 antigen named anti-HM1.24 MoAb. The presence of the HM1.24 antigen on the erythrocyte membranes and the erythrocyte agglutination following the addition of anti-HM1.24 MoAb was examined. In addition, an indirect Coombs' test, a hemolysis assay and the measurement of anti-single stranded-DNA antibodies were performed using test animal serum or plasma. The specific binding of FITC- and 125I-labeled anti-HM1.24 MoAb to the erythrocyte membrane was not observed. HM1.24 antigen was not identified on the erythrocyte membranes. However, a high concentration (more than 713 microg/mL) of anti-HM1.24 MoAb hemagglutinated the erythrocyte suspensions. The cause of this agglutination was unclear, but it is assumed that the non-specific binding and/or adhesion caused the direct agglutination. In the examination using test serum from the anemic monkeys, a positive reaction in the indirect Coombs' test was noted. Moreover, in these Coombs' test-positive animals, the production of anti-single stranded-DNA antibodies was sequentially increased. In the female monkey sacrificed in extremis due to severe anemia, an in vitro hemolytic reaction was detected attributable to complement activation. From these results, the hemolytic anemia detected in the repeated-dose toxicity study was diagnosed as a drug-induced autoimmune hemolytic anemia (AIHA) and the primary cause was assumed to be production of IgG class anti-erythrocyte autoantibodies. (+info)
INDUCTION OF LABOUR FOR PREVENTION OF STILLBIRTH FROM RH HEMOLYTIC DISEASE.
(30/208)
The fate of 80 infants delivered after induction of labour in 72 Rh-sensitized mothers was studied to determine whether the stillbirth rate could be reduced. Labour was induced at 32 to 39 weeks of gestation; the criteria for induction were based on the history of previously affected infants, and a maternal Rh-antibody titre of 1/40 or greater, using an indirect antiglobulin technique. Nine mothers were delivered by Cesarean section. It was estimated that 26 infants were so severely affected as to be unlikely to have survived to term. However, only seven died, and one was stillborn. Two of these would normally have survived, one being Rh-negative. These two cases demonstrated the main danger in this method of management. There was a probable saving of 18 infants. In 22 mothers there was no history of previous delivery of an affected infant; in all 22 the infants survived, though six probably would not have survived to term. In 15 pregnancies in which the mothers had had a previous stillbirth, 12 infants survived. Sixty-seven infants required a total of 116 exchange transfusions. Despite the hazards it is concluded that early induction has an important place in management of Rh hemolytic disease. (+info)
HEMOLYTIC TRANSFUSION REACTIONS.
(31/208)
After receiving apparently compatible blood three patients suffered hemolytic reactions. The compatibility tests were by saline and indirect Coombs technique including a screening tube of group 0 cells. The antibodies responsible for these reactions were not clearly demonstrable for several days following the transfusion. In two instances the antibody was anti-E.These case reports point up the following. (a) Currently used cross-matching procedures will occasionally fail to demonstrate an incompatibility. (b) In two of the cases the direct Coombs test was negative on an immediate post-transfusion specimen, when it could have been of great aid in diagnosis. (c) When a transfusion reaction of hemolytic type is suspected, a follow-up study several days after the reaction may clarify the diagnosis; when possible, transfusions should be avoided in the interim. (+info)
THE DIRECT ANTIGLOBULIN (COOMBS) TEST IN MEGALOBLASTIC ANAEMIA.
(32/208)
Folic acid deficiency with the picture of a megaloblastic bone marrow may develop in haemolytic anaemia, and, on the other hand, both vitamin B(12) and folic acid deficiency may produce signs of haemolysis. As the correct interpretation of a positive antiglobulin reaction associated with megaloblastic erythropoiesis is particularly important, the effect of deficiency of vitamin B(12) and folic acid on the results of the test was investigated in 32 patients with vitamin B(12) or folic acid deficiency and a positive antiglobulin reaction was obtained in ten. There was no correlation between the result of the test and the degree of anaemia, and there was no significant difference between the incidence of positive results associated with deficiency of vitamin B(12) or folic acid. In determining the significance of a positive result, the time interval before agglutination occurs is sometimes of greater value than the strength of the reaction or the result of the gamma globulin neutralization test. (+info)