A Case of Anti-Jk(a) Whose Reactivity Was Abolished in an Enzyme Gel Test / 대한수혈학회지

We report a case of Anti-Jk(a), whose reactivity was abolished in an enzyme gel test. A 56-year-old woman was admitted to our hospital because of fever, myalgia, nausea and vomiting. Anti-Jk(a) was detected by antibody screening and an identification test using a LISS/Coombs gel card (DiaMed AG, Cressier sur Morat, Switzwerland). Its reactivity was so weak (trace ~ 1+) that an Enzyme gel card (DiaMed AG) was added to enhance the reactivity. Unexpectedly, all reactions with the enzyme-treated cells showed negative results. The patient's RBC phenotype was Jk(a-b+). The abdominal CT revealed a 6x7.5 cm sized liver abscess. Her condition improved after percutaneous catheter drainage and she was discharged on the 23rd hospital day.

Screening of Apheresis Platelet Donors for Human Parvovirus B19 by Gel Card Test / 대한수혈학회지

BACKGROUND: As apheresis platelet concentrates are widely used recently, the risk of transfusion associated infections is increased. Parvovirus B19 causes transfusion associated infections especially in chronic hemolytic anemia, haemophilia or immunosuppressed patients. We evaluated the significance of Parvovirus B19 antigen test to be one of the apheresis platelet donor screening test. METHODS: Three hundred forty eight serum (or plasma) samples from apheresis platelet donors were tested for Parvovirus B19 antigen test which was based on haemagglutination in gel technology. The tubes arranged in special gel cards (DiaMed) were added with 25 microL P antigen positive red cell and 10 microL patient's serum and then centrifuged at room temperature, 85 g for 10 minutes without incubation. The result was read and scored from 0 to 4 positive. Also the antibody screening test was performed for all of the positive samples on the Parvovirus B19 gel card test to exclude false positive reaction due to red cell alloantibody. We investigated directed recipient's disease state for all of positive donors and compared the result of the Parvovirus B19 antigen test with the routine screening test. RESLUTS: Six of the 348 samples were positive for Parvovirus B19 antigen test, the frequency was 1.7%. All of the six positive samples on gel card test reveal negative result by the antibody screening test. All of four directed recipients are immunosuppressed states. If the Parvovirus B19 antigen test was included in routine screening test, the rejection rate is expected to be increased about 1.4%. CONCLUSION: Screening for Parvovirus B 19 in apheresis platelet donors is considered to prevent transfusion mediated viral infection of susceptible recipients including immunocompromised patients.

Irregular Antibody Positivity in Women Blood Donors with History of Parturition / 대한수혈학회지

BACKGROUND: Antibody screening for donated blood is not yet being performed in Korea. Positive rate of irregular antibodies in Korean patients or blood donors has been thought to be much lower than that of foreign contries. We studied to know the actual frequency of irregular antibodies in blood donors with history of parturition using gel card, which was recently introduced in the field of blood banking and considered to be easy to standardize and sensitive to detect irregular antibodies. METHODS: 706 samples were collected from four blood centers in Seoul for 4 months. Antibody screening and identification were done by two kinds of Gel Card (DiaMed-ID corp, DiaMed, Murten, Switzerland) such as Nacl/Enzyme and LISS/Coombs' card. Adsorption- elution test was done in samples of which we could know the antibody specificity. RESULTS: Irregular antibodies were identified in 24 cases among 706 samples, therefore the overall frequency was 3.4% (95% CI: 3.4% +/- 1.3%). Only 4 cases, however, showed positive reaction in both enzyme and Coombs' phase, therefore frequency of clinically significant antibodies was 0.57% (95% CI: 0.57% +/- 0.55%). The identified irregular antibodies were anti-Lea (8 cases), Anti-Rh (3 cases) and Anti-P1 (1 case). Adsorption-elution test showed positive reaction only in 3 cases with anti-Rh antibodies. CONCLUSION: Considering that blood donors with history of parturition comprize just little proportion of total donors in Korea and frequency of irregular antibody is relatively lower than that of foreign countries in same group (0.57% vs 3.8%), it can be concluded that antibody screening be not urgent problem in Korean blood donation program.