Post-transfusion hepatitis revisited.

OBJECTIVE: To evaluate the risk of post-transfusion and postoperative non-A non-B hepatitis in Australia immediately before the introduction of screening for hepatitis C. DESIGN: Retrospective testing of blood samples from a prospective study of cardiac surgery patients. Samples were taken from transfusion recipients and non-transfused controls at regular intervals for 12 months after surgery during 1987-1989. For all donor, recipient and control samples, alanine aminotransferase (ALT) levels were measured and tests for antibody to hepatitis B (anti-HBc, anti-HBs) and, when available, to hepatitis C (anti-HCV) were performed. SETTING: Cardiac surgery units. PARTICIPANTS: Participants were included if they lived in the metropolitan area, and had not had a transfusion in the past year. MAIN OUTCOME MEASURES: Post-transfusion hepatitis (two consecutive samples showing raised ALT levels, > 90 IU/L with no other known cause); hepatitis C infection and carriage (antibody to hepatitis C). RESULTS: Post-transfusion hepatitis occurred in 1.1% of 736 recipients of blood not screened for hepatitis C (i.e., two cases per 1000 unscreened units given). No hepatitis occurred in 514 controls. Seven of the eight patients with post-transfusion hepatitis seroconverted to hepatitis C virus infection. Seven of the 26 anti-HCV-positive donations transmitted hepatitis C, six of these were positive by recombinant immunoblot assay (RIBA) (one by second generation testing only) and one was RIBA indeterminate. Nineteen were RIBA non-reactive; one transmitted hepatitis but the recipient did not develop anti-HCV, although hepatitis C RNA was detected in the donation. Serum ALT was raised in four of the six infective donations. CONCLUSIONS: Hepatitis C virus infection accounted for almost all cases of non-A non-B post-transfusion hepatitis. First generation anti-HCV tests detected about 85% of infective donations. Surrogate testing of donations by ALT or anti-HBc offers no additional advantage.

Prevalence of hepatitis C virus antibodies in Sydney blood donors.

OBJECTIVE: To determine the prevalence of hepatitis C virus (HCV) antibodies in the Sydney blood donor population. DESIGN: All blood donations collected from Red Cross blood donors in Sydney from February 1990 until April 1991 were tested for HCV antibodies. For those samples found reactive in an anti-HCV screening test, a confirmatory test was carried out for the presence of HCV antibodies and the alanine aminotransferase level was measured. RESULTS: The prevalence of repeated reactivity to the screening test was 0.45% among blood donations overall, and 1.02% in donors giving blood for the first time in the study period. The confirmatory test result was positive for 30.8% of donations found to be repeatedly reactive in the screening test. There was little change over the study period in the HCV antibody prevalence of donors giving blood for the first time, but there was a clear decrease in the prevalence among all donations. Prevalence in males was nearly twice the prevalence in females--a difference which was consistent across age groups. The highest prevalence in both sexes was in the age group 30-34 years. Among samples for which the screening test results was positive, there was a strong correlation between the reactivity recorded for the screening test and both the proportion found positive by the confirmatory test and the proportion with an elevated alanine aminotransferase level. CONCLUSION: The small proportion of blood donations found to be repeatedly reactive by anti-HCV screening and the relatively good correlation with the confirmatory test and liver function assay indicate that a policy of discarding these donations will decrease the risk of transfusion-transmitted HCV infection without materially affecting the supply of blood.

Risk factors for hepatitis C virus infection in blood donors: a case-control study.

OBJECTIVE: To investigate risk factors for hepatitis C virus (HCV) infection in Sydney blood donors. DESIGN: Blood donors confirmed to be positive for HCV antibodies were compared with blood donors with a positive result of a screening assay, but whose HCV antibody status had not been confirmed. A questionnaire on sexual, parenteral and other potential risk factors was administered to both groups. SETTING: Blood Transfusion Service in Sydney. PARTICIPANTS: The study enrolled 220 donors who had confirmed HCV infection, and 210 donors who did not. RESULTS: The relative risk associated with injecting drug use was 63 (95% confidence interval, 19-260) when comparison was made with all other donors. Among donors who did not report injecting drug use, a significant, independent increase in risk was found in association with having had a tattoo. Among donors who did not give a history of parenteral exposure, there was a significantly greater risk in people with more than one life-time sexual partner than in those with at most one partner. CONCLUSION: A history of injecting drug use was elicited as the most important risk factor in Sydney blood donors with antibodies to hepatitis C. Having had a tattoo, and an increased number of lifetime sexual partners were also independently associated with HCV infection.

Clinical assessment and incidence of hepatitis C RNA in 50 consecutive RIBA-positive volunteer blood donors.

OBJECTIVES: (i) To assess evidence of liver disease in 50 consecutive volunteer blood donors who were anti-hepatitis C virus (anti-HCV) antibody positive and who were referred to one hepatologist; (ii) to assay for viral RNA in serum in these patients. SETTING: Royal Prince Alfred Hospital, a teaching hospital of the University of Sydney. PATIENTS: Fifty people who were detected by the NSW Red Cross Blood Transfusion Service to be anti-HCV antibody positive and to have a positive result on recombinant immunoblot assay (RIBA) were assessed by one hepatologist for symptoms, signs and biochemical evidence of hepatic dysfunction. These patients were consecutive referrals from this source. Sixteen of these patients also consented to liver biopsy assessment. All patients had serum assayed for viral RNA by polymerase chain reaction with a combination of 3' and 5' primers. RESULTS: The 50 blood donors consisted of 28 men and 22 women, with a mean age of 34.5 years. Forty-six patients were asymptomatic. Only six had a past history of hepatitis while 14 had minor signs of chronic liver disease. In 28, injecting drug use was thought the most likely source of exposure to HCV. The minimal mean time since exposure to HCV in these patients was 8.8 +/- 5.2 years. Eight patients had received a blood transfusion at a mean time of 15.0 +/- 9.8 years from the time of consultation. The mean maximum level of alanine aminotransferase (ALT) in all 50 patients was 102.8 U/L. Five patients had persistently normal ALT levels; another 22 had at least one normal ALT level. Liver biopsies indicated chronic persistent hepatitis in 11 patients, mild chronic active hepatitis in three patients and more severe chronic active hepatitis in one. One patient had cirrhosis on biopsy. Forty-two patients had viral RNA detected in serum. CONCLUSION: Chronic infection with HCV in blood donors was invariably asymptomatic; 78% of patients had no signs of chronic liver disease and 68% had a maximum hepatic transaminase level of less than 100 U/L. Although severe liver disease was seen in two of 16 biopsies, the majority of these patients have mild liver disease despite a mean of about 10 years since exposure to the virus. Eighty-four per cent of patients had evidence of viral RNA in serum.

A new cathodal Gc variant in Australia.

A new cathodal Gc variant and a known rare variant were found in a study of 307 Australian caucasian blood donors, each with a gene frequency of 0.28%. The frequencies of the other alleles were 0.161 (Gc1F), 0.557 (Gc1S) and 0.279 (Gc2), and were comparable with those of two earlier surveys.

Isoelectric focusing studies of transferrin and haptoglobin subtypes in an Australian white population.

This investigation presents the results of Hp and Tf subtyping of sera from 307 Australian whites by means of isoelectric focusing. Five Hp alleles were detected, these being Hp1F = 0.168, Hp1S = 0.235, Hp2FF = 0.003, Hp2FS = 0.561 and Hp2SS = 0.033. In the Tf system six alleles were found, TfC1 = 0.761, TfC2 = 0.176, TfC3 = 0.054, TfC6 = 0.002, TfB = 0.006 and TfD = 0.002. The usefulness of IEF together with modifications was highlighted for differentiating Tf and Hp subtypes; in particular, the absence of Hp2FF and Hp2SS in some earlier studies could be related to the technique used. The implication of the simultaneous presence of B and D transferrin variants in Caucasian populations is discussed.

Thirty-five-day modified red cells and 7-day stored platelet concentrates from triple bags of identical PVC formulation.

There is continuous need for blood components with long shelf life. To this end the 'circle' triple pack has been modified to provide 35-day red cell and 7-day platelet concentrates, in PVC bags of identical formulation and 0.4 mm thick. The plasticizer is a mixture of DEHP and TOTM (CLX Mark II). The primary pack contains 63 ml of CP 277.5 mM glucose. The third pack contains 100 ml of citric acid 2 mM, trisodium citrate 20 mM, NaH2PO4 20 mM, NaCl 123 mM, glucose 40 mM, and adenine 1.26 mM. Plasma is adenine-free. With these modifications both hard- and soft-spun red cells gave satisfactory biochemical and autologous survival indices up to 35 days of storage, the haematocrit not exceeding 60%. Platelet concentrates were acceptable at 7 days of shelf-life.

Eosinophilia, mast cell hyperplasia and antibody production in rats following an intraperitoneal injection of Ascaris cuticle including in-vitro studies of immune eosinophil granule lysis.

A single intraperitoneal injection of Ascaris cuticle caused a local eosinophilia with peak levels at 2 wk after injection. Mast cells reduced in number and size at 1 wk were found in increased numbers at 3 wk. Injection of a collagen-poor fraction of cuticle known as "cuticlin" resulted in a diminished eosinophil and mast cell response compared with injection of whole cuticle. Precipitating antibodies to soluble Ascaris cuticle collagen were detected in the serum and peritoneal fluid from day 5 onward. It is proposed that the eosinophilia and mast cell hyperplasia are the result of immunization of the animal to an antigen present in Ascaris collagen and rendered soluble by the action of mononuclear phagocytes. The eosinophil and mast cell response to Ascaris cuticle mimicked the response in connective tissue to living nematode parasites. It is concluded that the cuticle of nematode parasites may be responsible for eosinophilia and mast cell hyperplasia in the host.

Survival of transfused platelets collected into new formulation plastic packs.

Platelet concentrates were prepared in plastic packs of polyvinyl chloride with tri(2-ethylhexyl) trimellitate as plasticizer. They were stored, with gentle shaking, at room temperature for periods up to 7 days before labelling with isotope and reinfusing. In vivo survival studies, platelet counts, pH and electron microscopy indicated that platelet concentrates prepared in the new plastic were superior to those prepared in the standard pack currently in use. Oxygen was found to diffuse through the new pack more rapidly than through the standard pack. A shelflife of up to 1 week at room temperature seems possible for platelet concentrates prepared in the new plastic.

Modification of the platelet suspension immunofluorescence test.

This study reports two modifications of the Platelet Suspension Immunofluorescence Test which make it more convenient to use for the rapid identification of platelet-specific antibodies and for screening individuals if platelet donors of a particular type are urgently required. Platelets frozen both before and after paraformaldehyde (PFA) fixation were compared with fresh PFA-fixed platelets using anti-PLA1 and anti-HLA antisera. Further, a comparison was made between the results of the test when performed in tissue culture trays or in tubes as originally described. Platelets, prefixed with PFA and then frozen appeared similar in all respects to fresh PFA-fixed platelets with no loss of antigenicity and no non-specific fluorescence. Although platelets fixed after frozen storage were also satisfactory, they were less convenient to use and lost some brilliance in staining. When the test was performed in tissue culture trays, there was no loss in sensitivity, and the volume of antiserum used was halved. However, the main advantage was the efficiency and ease with which the test could be performed, especially when handling large numbers of samples.

Prothrombin times: an evaluation of four thromboplastins and four machines.

The prothrombin times of 63 patients on oral anticoagulant therapy were tested using 4 different thromboplastins; 2 rabbit brains (Simplastin & Ortho), human placenta (Thromborel) and human brain (Australasian Reference Thromboplastin--ART). Four machines measuring the one-stage prothrombin times were compared with the manual method. Each of the machines and thromboplastins showed highly reproducible and predictable results, but there were differences in thromboplastin sensitivities which would pose major therapeutic problems. A system of correcting ratios of different thromboplastins to a reference preparation would overcome these differences in thromboplastin sensitivities. All thromboplastins gave comparable results with the Clotek, MLA 600 and Coag-A-Pet machines and manual method. Cortek gave comparable ratios with the ART but not with any other thromboplastin.

Eosinophilia and mast cell hyperplasia induced by parasite phospholipid.

Phospholipid preparations from the nematode Ascaris suum or cysts of Echinococcus granulosus (hydatid cysts) induced an eosinophilia when injected into the peritoneal cavity of rats. Peritoneal eosinophilia persisted throughout 21 days of daily injections of Ascaris lipid and was accompanied by blood eosinophilia, mast cell granule lysis and mast cell hyperplasia. The active material consisted of lecithin and lecithin plasmalogen, and in aqueous suspension had a membrane-like appearance. Electron microscopy revealed that the phospholipid was ingested by all types of cells in the peritoneal cavity, including mast cells, and was rapidly broken down by eosinophils. Phagocytosis was found to be complement dependent. The lipid combined with properdin in human serum and stimulated complement breakdown via the alternative complement pathway.