Raised serum alkaline phosphatase activity in one family.

Eleven members of the same family were studied after an incidental detection of raised serum alkaline phosphatase activity in one of them without any apparent underlying cause. Three other members were found to have the same abnormality; none of them had an associated disease. In the four cases with elevated serum alkaline phosphatase levels, its activity showed a preponderance of the bone isoenzyme. Studies of the erythrocyte and histocompatibility antigens in nine members of the family, as well as idiograms of karyotypes of four of them, did not show any relation between histocompatibility antigens and the raised levels of serum alkaline phosphatase. Also, no chromosomal abnormality is shown from karyotypes. The data suggest a probable autosomal dominant pattern of inheritance.

Autoanti-D in a patient after cladribine treatment for lymphoplasmocytic lymphoma.

We report the case of a 62-year-old woman who developed an autoanti-D after cladribine treatment. In May 2000, the patient underwent splenectomy for a stage IV-B lymphoplasmocytic lymphoma. She was transfused with ABO- and Rh(D)-matched blood. A month later, she received chemotherapy with cladribine. In February 2001, blood grouping showed her to be AB, D+ and the direct antiglobulin test was positive for IgG. An autoanti-D was identified in the eluate. Genotypic analysis confirmed the Rh phenotype of the patient as ccDEe. No hemolysis was evident, as judged by the absence of anemia, a bilirubin of 15.7 micromol/L, and lactic dehydrogenase of 412 IU/L. When an anti-D is identified in a D+ blood recipient, a passive transfer of anti-D, and an alloimmunization in a recipient with a weak D phenotype, should be ruled out. Finally, as in our case, an autoantibody is an additional possibility.

One thousand seventy antibodies detected only by a 2-stage papain test: wanted and unwanted positive reactions.

Despite the wide use of the antibody detection test for unexpected antibodies, controversy still remains regarding the use of enzyme-treated red blood cells. Over a 6-year period, 72,573 samples from 49,863 patients submitted for pretransfusion compatibility testing were examined for unexpected antibodies. The antibody detection tests included a low-ionic-strength solution (LISS) indirect antiglobulin test and a two-stage papain (2SP) test. One thousand and seventy of the 2267 (47%) antibodies tested by 2SP were reactive only by the 2SP test. Overall, the 2SP test detected only 0.6% of antibodies considered to be clinically significant (10 examples of anti-c and 2 examples of anti-e). The slight additional safety provided by detection of clinically-significant antibodies is overshadowed by the high number of clinically-insignificant antibodies detected by the 2SP test.

The direct antiglobulin test in a hospital setting.

To evaluate the current use of the DAT in our hospital,we reviewed the charts of all patients who had a DAT performed in our laboratory. The collected data included DAT results and a previously completed laboratory evaluation of suspected hemolytic anemia. Four hundred sixty-three DATs were performed in our laboratory from April 1999 to October 2001. The DAT was negative in 434 (93.7%) cases and positive in 29 (6.3%) cases. A complete laboratory evaluation of suspected hemolytic anemia was seen in 179 (38.7%) cases. The incidence of a positive DAT was higher in the group of patients with > 2 signs of hemolysis (4/34 cases; 11.8%) than in the group of patients with

Disulphide bonds are a requirement for adsorption of cephalosporins on the red cell membrane.

The authors studied the behavior of red cells (RBCs), treated with 2-aminoethylisothiouronium bromide (AET), against 100 serums containing cephalothin antibodies and 27 serums with cephapirin antibodies. None of the serums reacted with cephalosporin-coated RBCs that had been exposed previously to AET. The possibility of the Kell system acting as a receptor for cephalosporins was excluded. The authors discuss the significance of cysteine disulphide bonds and the tertiary or quaternary structure of red cell membrane proteins in the binding of cephalosporins to RBCs.

Autoimmune thrombocytopenia: serological behavior of platelet antibodies.

The study of the specificity of platelet autoantibodies has made it possible to expand our knowledge about the immune characterization of idiopathic thrombocytopenic purpura. We report on a study of eluates obtained from 10 patients' platelets with autoimmune thrombocytopenia. They were tested with platelets obtained from healthy donors (Zw a + and Zw a-) and with type I Glanzmann platelets. Our results, as those reported by van Leeuwen et al. in 1982, suggest that the autoantibodies recognize one or more antigenic markers probably carried by glycoproteins IIb and IIIa.

Antirifampicin antibodies in acute rifampicin-associated renal failure.

5 patients with acute renal failure (3 with thrombopenia and hemolysis) induced by the reintroduction of rifampicin are described. No correlation was found between the severity of clinical manifestations and the total dose taken by the patients. In all but 1 patient, antirifampicin antibodies were detected. Antibodies suggested to be of the IgM class were detected in all 3 patients with hematological disorders. The pattern of non-specific acute tubular necrosis found in the 2 biopsied patients, indistinguishable from that of ischemic origin, raised the possibility of a vascular-mediated damage. In 3 patients, the possibility of a triggering immunoallergic mechanism is discussed.

High rate of infectivity and liver disease in blood donors with antibodies to hepatitis C virus.

OBJECTIVE: To determine the epidemiologic, clinical, serologic, and histologic importance of antibodies to hepatitis C virus (anti-HCV) in blood donors. DESIGN: Cross-sectional identification and prospective evaluation of seropositive donors; retrospective assessment of infectivity; and nested case-control study for risk factors. SETTING: Liver unit of a referral-based university hospital. SUBJECTS: Of 30,231 consecutive donors, 368 (1.2%) were found to be anti-HCV-reactive by enzyme-linked immunosorbent assay (ELISA). Two hundred and fifty-four of these 368 donors were evaluated for risk factors by comparison with 284 age- and sex-matched controls. Eighty-six spouses of seropositive donors were also evaluated. MEASUREMENTS AND MAIN RESULTS: Twenty-four percent of the seropositive donors had a history of percutaneous exposure to blood. This rate increased to 45% when only those donors confirmed to be anti-HCV positive by a second-generation recombinant immunoblot assay (RIBA-2) were considered. A family history of liver disease (odds ratio, 2.8; 95% Cl, 1.6 to 4.8), previous blood transfusion (odds ratio, 6.1; 95% Cl, 3 to 12.5), and a history of tattooing or intravenous drug abuse (odds ratio, 8.4; 95% Cl, 2.3 to 31) were associated with anti-HCV seropositivity. An elevated alanine aminotransferase (ALT) level was found in 58% of the seropositive donors. Of the 150 donors tested, 104 (69%; Cl, 62% to 77%) were confirmed by RIBA-2 to be anti-HCV positive. Of the 105 donors who had a biopsy, 16% had normal histologic findings, 11% had minimal changes, 21% had chronic persistent hepatitis, 45% had chronic active hepatitis, and 7% had active cirrhosis. All 77 donors with RIBA-2-confirmed seropositivity had histologic abnormalities. Of 43 donors evaluated in an infectivity study, 82% were implicated in previous HCV transmission. Only 2.3% of the spouses were anti-HCV positive. The ELISA, RIBA-2, and ALT results correlated with infectivity and abnormal histologic findings. CONCLUSIONS: In our geographic area, almost 70% of donors who are anti-HCV positive by ELISA are confirmed to be positive by RIBA-2; most of these donors appear to be chronic carriers of HCV and have substantial liver disease.

Evaluation of antibodies to hepatitis C virus in a study of transfusion-associated hepatitis.

BACKGROUND: The hepatitis C virus (HCV) is now known to be the chief cause of transfusion-associated non-A, non-B hepatitis, but the prevalence of HCV among blood donors and the frequency of transmission by blood transfusion are unknown. METHODS: To assess the sensitivity and specificity of a test for antibody to HCV, we tested serum samples from participants in a large study of transfusion-associated hepatitis. Samples were obtained prospectively from consecutive adults undergoing open-heart surgery in Spain, but were tested retrospectively, after the antibody enzyme immunoassay for anti-HCV became available. RESULTS: Of 280 transfusion recipients given a total of 1109 units of blood, 27 (9.6 percent) had transfusion-associated non-A, non-B hepatitis (mean follow-up, 52 weeks) and 24 of the 27 seroconverted to anti-HCV-positive, whereas only 2 (0.8 percent) of the remaining transfusion recipients seroconverted. Among the 1044 donor specimens available for testing, 16 (1.5 percent) had anti-HCV antibody. Only 1 additional seropositive donor was found when 44 implicated donors who had been seronegative were retested 9 to 12 months later. Of the 16 recipients of anti-HCV-positive blood, 14 (88 percent) had transfusion-associated hepatitis and seroconverted to anti-HCV-positive. The remaining two recipients had neither hepatitis nor anti-HCV antibody. Among 25 patients with non-A, non-B hepatitis for whom all transfused blood was tested, 14 had received blood positive for anti-HCV. CONCLUSIONS: About 90 percent of blood donors with antibody to HCV have infectious virus in their blood. The screening of blood donors for anti-HCV antibody should prevent about half the cases of transfusion-associated hepatitis, but the donors with infectious virus who are anti-HCV-negative may remain seronegative for prolonged periods.

[Autoimmune hemolytic anemia and myelodysplastic syndromes]. / Anemia hemolítica autoinmune y síndromes mielodisplásicos.

The association between autoimmune haemolytic anaemia (AHA) and myelodysplastic syndromes (MDS) was found in seven out of 156 patients with SMD who received several transfusions as supportive therapy. Three patients were diagnosed of refractory anaemia (RA), three more of refractory anaemia with excess of blasts (RAEB) and one of refractory anaemia with ring sideroblasts (RARS). All patients showed a positive direct antiglobulin test (DAT) and the presence of anti-red blood cell IgG type antibodies, both in serum and eluate. Clinically, three patients showed signs of low grade haemolysis. It is suggested that in the reported patients, who seem to be immunologically predisposed, red blood cell transfusions could trigger the autoantibodies and the AHA development.