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Biomedical subjects

I A Shulman

Publications and source records attributed to I A Shulman.

77 records · Page 5Linked to original sources
PubMedDate not supplied

Effect of delayed centrifugation or reading on the detection of ABO incompatibility by the immediate-spin crossmatch.

The immediate-spin (IS) crossmatch is a method that detects ABO incompatibility. However, under certain circumstances, this test may show unwanted negative or weak results, even though the red cells (RBCs) and serum being tested are ABO incompatible with each other. The present study investigated the potential effect of delayed centrifugation or reading on the IS crossmatch test performance. When the centrifugation step of the IS crossmatch between group O sera and group A1 RBCs was delayed for 2 minutes, 5 of 200 crossmatches showed no agglutination with only trace (n = 2) or moderate (n = 3) hemolysis, and one crossmatch showed only weak, macroscopic agglutination, but moderate hemolysis. All six sera contained A antibodies that were lytic in vitro and, therefore, probably were capable of causing in vivo hemolysis of transfused A1 RBCs. Delaying the reading of the IS crossmatch test for 2 minutes had no apparent effect on test performance. These data demonstrate the importance of technologists' recognition of hemolysis as a positive result on IS crossmatches, especially if the performance of the centrifugation step of the test is delayed. Furthermore, the unwanted negative agglutination results were abolished by suspending the group A1 RBCs in saline containing EDTA. The authors' laboratory has modified its IS crossmatch procedure so that donor RBCs are routinely suspended in saline containing EDTA before testing. This procedural change should increase the safety of the IS crossmatch.

ABO Blood-Group System↗
PubMedDate not supplied

Prevalence of antibody to Trypanosoma cruzi among blood donors in Los Angeles, California.

Transfusion-associated Chagas' disease is a serious public health problem in Central and South America. With the recent influx of immigrants from Chagas' disease-endemic areas, concern about the risk of disease from blood transfusion has increased in the United States. To assess the prevalence of Trypanosoma cruzi infection in one area, 1024 consecutive blood donations from 988 voluntary blood donors at a medical center in Los Angeles County were screened serologically. The median age of donors screened was 32.5 years; 53.4 percent were male, and 38.4 percent were born in Chagas' disease-endemic countries. All donor sera were tested by complement fixation (CF) and indirect immunofluorescence (IIF) tests. A radioimmunoprecipitation assay (RIPA) was also done on all sera from CF- or IIF-reactive donors and an equal number of sera from nonreactive donors. A second serum specimen was obtained, and interviews were completed for 18 (67%) of 27 donors with an initial CF titer greater than or equal to 8 or an IIF titer greater than or equal to 64. The overall seroreactivity (by CF and IIF) was 1.1 percent (11/988). One donor (0.1%) had antibody specific to the 72- and 90-kDa antigens of T. cruzi on RIPA. Seven recipients of blood components from the seroreactive donors were located and were seronegative at 3 to 6 months. Seroreactive donors were 3.6 times more likely to have been born or to have resided in Mexico or Central America, 8.7 times more likely to have donated blood in the past, and 11.8 times more likely to have a history of malaria prophylaxis or treatment.

Adolescent↗
PubMedDate not supplied

Different HLA haplotypes in Mexican Americans with IDDM.

The study of HLA histocompatibility antigens and insulin-dependent diabetes mellitus (IDDM) in non-White populations may provide a unique opportunity to more accurately define the diabetes susceptibility gene(s) located within the HLA region. To determine whether HLA haplotypes differ between ethnic groups, we compared 105 HLA haplotypes from 55 Mexican-American IDDM patients with 272 haplotypes from 136 IDDM patients of non-Hispanic White descent. The accurate determination of genotypes and haplotypes requires the study of family units. Therefore, all diabetic patients in this study were from studies of families having one or more siblings with IDDM. In the Mexican-American group, HLA-DR3 and -DR4 were the most common HLA-DR alleles and were present in comparable frequencies in the non-Hispanic White group (HLA-DR3, 27% of Mexican-American and 29% of non-Hispanic White haplotypes; DR4, 46% of Mexican-American and 43% of non-Hispanic White haplotypes). However, the HLA-B/DR-containing haplotypes and haplotype frequencies differed between the two groups. Several common haplotypes (B8/DR3, B15/DR4) in the non-Hispanic White group occurred less frequently in the Mexican-American group. In contrast, uncommon haplotypes in the non-Hispanic White group comprised nearly 50% of the DR4-containing haplotypes (B35/DR4, B40/DR4, B44/DR4) in the Mexican-American group. Although both DR3- and DR4-haplotype frequencies differed significantly between the two groups, the relative frequency of DR3- but not DR4-containing haplotypes was similar in both ethnic groups. This adds to the evidence suggesting that different susceptibilities are provided by the haplotypes carrying the DR3 and DR4 alleles.

Alleles↗
PubMedDate not supplied

Autoimmune hemolytic anemia with both cold and warm autoantibodies.

Of 144 patients with a positive direct antiglobulin test and having autoimmune hemolytic anemia (AIHA), 12 (8.3%) satisfied diagnostic criteria for both warm antibody AIHA and cold agglutinin syndrome. All 12 patients had IgG and C3d sensitizing their erythrocytes, and samples of their serum contained IgM cold autohemagglutinins optimally reactive at 4 degrees C, but with a high thermal amplitude to 37 degrees C, and IgG warm autoantibodies. All red blood cell eluates contained IgG warm autoantibodies. The 12 patients had severe hemolytic anemia that responded dramatically to corticosteroid therapy, with the mean hemoglobin level increasing from 6.3 to 12.9 g/dL. Five patients (42%) had systemic lupus erythematosus, one patient (8%) had a non-Hodgkin's lymphoma, and six patients (50%) had idiopathic AIHA; four patients (33%) had concomitant thrombocytopenia (Evans' syndrome). Nine patients (75%) were female. Four patients had unexpected alloantibodies potentially capable of in vivo hemolysis of transfused blood. Because of the severe hemolysis, the serologic findings, and the dramatic initial clinical response to corticosteroid therapy, these patients represent a distinct catagory of AIHA and should be given corticosteroid therapy quickly.

Adolescent↗