IgG and IgM anti-A and/or -B agglutinin titers were determined on 17 serum samples (5 group 0, 7 group A, 5 group B) to range from 8 to 1024. The presence of hemolysins was also evaluated. Single adsorptions with solid-state synthetic A and B substances greatly reduced or eliminated anti-A and -B titers but did not adsorb known platelet antibodies. Unadsorbed and adsorbed serum samples were crossmatched with ABO-compatible and -incompatible platelets by a radioimmunoassay employing 125I-labeled monoclonal antibodies specific for human gamma, mu, and C3d antigens. IgG and IgM crossmatch incompatibility was directly related to ABO alloantibody titers greater than or equal to 64. The use of adsorbed serum in the crossmatch eliminated or greatly reduced incompatible results that were due to ABO alloagglutinins alone, thus allowing the reliable detection of platelet and/or HLA antibodies.

ABO Blood-Group System↗

PubMed1989

Preliminary trial of minidose heparin prophylaxis for painful sickle cell crises.

Four patients with well-documented severe recurrent painful sickle cell crises received 12-month courses of self-administered minidose heparin (5000-7500 units every 12 hours). Patients were evaluated weekly or bi-weekly for symptoms and signs of sickle crises. The observations were compared with identical observations during 12 months off heparin (control). Prior to starting heparin, baseline laboratory values were established, including hematocrits, platelet counts, and plasma coagulation factors. Bone density was evaluated by radiologic measurement of metacarpal cortical width and by forearm transmission osteodensitometry. Laboratory values were repeated at each visit; bone density was reevaluated every 6 months. At each visit clinical status for the preceding 1-2 weeks was classified as: no pain (I), minor pain controllable by non-prescription medications (II), pain requiring office or emergency room admissions for parenteral narcotics (III), hospitalized for about 3 days for pain crisis (IV). One patient completed a single 2-year cycle; one patient completed 2 cycles (followed 4 years), and 2 patients have undertaken 3 cycles (followed greater than or equal to 6 years). No treatment-related complications occurred requiring discontinuation of heparin. Thrombocytopenia was not observed. There was no evidence of progressive osteopenia. All patients improved while receiving heparin; 1 moderately, 3 markedly. Cumulative data (8.7 patient years on heparin, 12 control years) revealed a 73% reduction in days of hospitalization per year and 74% reduction in hours spent in emergency rooms per year during heparin administration. Pretreatment pain patterns recurred when heparin was discontinued.

Adult↗