Epidemiology of blood transfusion.

BACKGROUND: Earlier investigations of the epidemiologic attributes of blood transfusion were not based on total community populations. To calculate incidence rates of the transfusion of blood and blood components in the general population and in age- and gender-specific groups, all residents of a United States county who received transfusion(s) from 1989 through 1992 were studied. STUDY DESIGN AND METHODS: The study was a prevalence survey (cross-sectional study) of a well-defined population at a specified time. RESULTS: There was no significant change in blood and blood component utilization from the beginning of 1989 through 1992. The incidence of red cell transfusion was 42.88 units per 1000 population per year in both men and women and varied from 12.08 units per 1000 population per year in those less than 41 years old to 245.24 units per 1000 population per year in the group aged more than 65. A random resident's probability of receiving transfusion(s) in any year was 0.89 percent (0.83% for men and 0.94% for women) and varied from 0.26 to 5.17 percent among the three age groups. The incidence of platelet and fresh-frozen plasma transfusion was 21.24 units per 1000 population per year and 8.64 units per 1000 population per year, respectively. CONCLUSION: Incidence rates of blood transfusion for "causal" planning of blood collections are presented here for the first time. The probability of receiving a transfusion of RBCs in any year rises by 20-fold from the rate in those less than 40 years old to that in those more than 65 years old, who receive 53.3 percent of the red cell units transfused.

Long-term survival after blood transfusion.

BACKGROUND: Look-back investigations of populations of patients admitted to major tertiary-care hospitals in the 1980s found a 2-year posttransfusion mortality rate in excess of 50 percent. To quantify the association of blood transfusion with mortality in a more broadly based population, a cohort of all residents of a United States county who underwent transfusion in 1981 was studied. STUDY DESIGN AND METHODS: Retrospective cohort study comprised 802 county residents. Complete follow-up (until death or for 10 years) was available on 93.9 percent. RESULTS: The median length of survival was 95.0 (+/- 2.5) months. Twenty-four percent of patients died within 1 year after the transfusion, 30 percent within 2 years, 40 percent within 5 years, and 52 percent within 10 years. The relative risk of death within 10 years increased by 4.1 percent per unit of red cells (p < 0.0001), by 1.2 percent per unit of platelets (p = 0.0003), and by 7.3 percent per unit of fresh-frozen plasma (p = 0.0018) received in 1981, after adjustment for the effects on mortality of age, gender, and number of days of hospitalization in 1981. CONCLUSION: Receipt of a blood transfusion can be used as a descriptive epidemiologic index of morbidity in the general population, as it is independently predictive of mortality, adding to the predictive value of age, gender, and previous hospitalization. There is a dose-response relationship between the amount of blood components received and a reduction in the subsequent length of survival. However, when a county's entire population is studied, posttransfusion mortality due to underlying disease is substantially lower than that previously reported in look-back investigations.

Errors in transfusion medicine. Detection, analysis, frequency, and prevention.

The Mayo Clinic (Rochester, Minn) Division of Transfusion Medicine evaluated the effect of methods of error detection, analysis, and prevention on the rate of errors occurring from 1982 through 1992. We defined an error as any deviation from the standard operating procedure. Twenty-four standard operating procedures were monitored for errors that related to donor processing, testing of donor blood, patient testing, and transfusion. The estimate of the overall error rate and 95% confidence interval fluctuated between 20 and 30 per 10(4) procedures. The transcription error rate declined from 21 to six per 10(4) procedures as a result of changes to systems using computer-generated labels and bar codes. We concluded that when errors are recognized, and appropriate system changes are made, these errors can be prevented.

Evidence against hepatitis viruses as important causes of severe autoimmune hepatitis in the United States.

To determine if the hepatitis viruses are important etiologic factors in autoimmune hepatitis, the clinical, immunoserologic, virologic and HLA phenotypes of 105 of the latter patients were assessed prospectively and compared to 45 patients with chronic viral hepatitis. Patients with autoimmune hepatitis were more often women with higher serum aspartate aminotransferase and immunoglobulin levels than patients with viral disease. Only eight patients (8%) were seropositive for anti-HBc and anti-HBs (four patients) or anti-HCV (four patients) and none with anti-HCV were reactive by second generation immunoassay or recombinant immunoblot assay. Smooth muscle (90 vs. 22%, P < 0.001) and antinuclear (70 vs. 22%, P < 0.001) antibodies were more common in patients with autoimmune hepatitis and the titers more frequently exceeded 1:80 (84 vs. 11%, P < 0.0001). Patients with autoimmune hepatitis were more often positive for HLA B8 (48 vs. 20%, P < 0.01) and DR3 (49 vs. 20%, P < 0.003) and they more frequently had the HLA A1-B8-DR3 phenotype (38 vs. 10%, P < 0.003). Only one of the 120 patients tested for anti-LKM1 was seropositive. We conclude that in an American referral population autoimmune hepatitis usually lacks virologic markers and has a distinctive clinical, immunoserologic and HLA phenotype. Hepatitis viruses are not important immunogenic stimuli for non-organ specific antibodies and they are unlikely to be important causes of this form of autoimmune hepatitis.

Effect of homologous fibrin adhesive on callus formation and extracortical bone bridging around a porous-coated segmental endoprosthesis in dogs.

Modular, porous-coated, titanium segmental endoprostheses were implanted bilaterally in the femoral diaphysis of 7 adult mixed-breed dogs. Autogenous bone graft in particle form was placed around the implant and bone. In 1 limb, homologous fibrin adhesive was mixed with the graft in situ before soft tissue closure. The contralateral limb was grafted in identical manner, but without fibrin adhesive, and served as a control. Radiography was performed immediately after surgery and 1, 2, 3, 4, 6, 8, 10, and 12 weeks later to assess callus area and bone remodeling. At 12 weeks, dogs were euthanatized and bone/implant fixation strength was tested under torsion and compared with values for 6 in vitro controls. Histomorphometric and microradiographic analyses of transverse sections of the distal portion of the implanted femurs were performed. Radiographic callus area was significantly (P < 0.05) smaller in the femurs grafted with fibrin adhesive, compared with the contralateral control. New bone formation (21.4 +/- 1.8% vs 19.2 +/- 2.4%), unlabeled bone (64.8 +/- 3.0% vs 67.9 +/- 4.2%), porosity (13.9 +/- 0.7% vs 12.9 +/- 0.8%), and bone ingrowth into the porous coating (10.3 +/- 0.9% vs 10.0 +/- 1.2%) were not significantly different between fibrin- and nonfibrin-grafted implants, respectively. There were no significant differences in torsional strength of implant fixation between the fibrin- and nonfibrin-grafted femurs or between the in vivo implanted femurs and the in vitro controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Randomized controlled trial of recombinant alpha-2a-interferon for chronic hepatitis C. Comparison of alanine aminotransferase normalization versus loss of HCV RNA and anti-HCV IgM.

We enrolled 32 patients with chronic hepatitis C into a randomized, controlled trial to evaluate the efficacy of recombinant alpha-2a-interferon treatment. Sixteen patients were randomized to receive 1.5 million units of recombinant alpha-2a-interferon subcutaneously, thrice weekly, for six months while the remaining 16 patients were randomized to a control group that received no treatment. The mean serum alanine aminotransferase (ALT) level during the six-month study period, expressed as a percentage of the prestudy baseline value, was 82% for the control group compared to 56% for the treatment group (P = 0.014). One fourth of the treatment group normalized their serum ALT level compared to only 6% of the controls (P = 0.05). During posttherapy follow-up, 86% of responders clinically relapsed. Loss of anti-HCV IgM and HCV RNA occurred exclusively in interferon-treated responders. Anti-interferon antibodies developed in 32% of all treated patients. Forty percent of nonresponders developed anti-interferon antibodies compared to only 14% of responders (P = NS). We conclude that recombinant alpha-2a-interferon is clinically effective in patients with chronic hepatitis C. However, most responders in this trial of low-dose interferon relapsed upon cessation of treatment.

Absence of hepatitis B virus DNA detected by polymerase chain reaction in blood donors who are hepatitis B surface antigen negative and antibody to hepatitis B core antigen positive from a United States population with a low prevalence of hepatitis B serologic markers.

A recent study in hepatitis B surface antigen (HBsAg)-negative, antibody to hepatitis B core antigen (anti-HBc)-positive blood donors from a population with a high prevalence of hepatitis B serologic markers showed the presence of hepatitis B virus DNA (HBV DNA) as detected by polymerase chain reaction (PCR) in 4 percent of these donors. A sensitive, nested PCR assay was used to assess the prevalence of HBV DNA in a population of HBsAg-negative, anti-HBc-positive blood donors from a United States population with a low prevalence of hepatitis B serologic markers. The lower limit for detection by the PCR assay was 10(-5) pg per mL of HBV DNA. There was a review of 26,492 consecutive blood donations in a 12-month period. During this time, only 1 unit (0.004%) was HBsAg positive. An additional 158 units (0.6%) were repeatably reactive for anti-HBc. These 158 HBsAg-negative, anti-HBc-positive units were given by 119 donors of blood for allogeneic and autologous use. HBV DNA was not detected by PCR in blood from 83 allogeneic blood donors (93 samples) or 36 autologous blood donors (65 samples). Anti-HBc testing is an inefficient means of screening for potential hepatitis B infectivity and is associated with low test specificity in populations with a low prevalence of hepatitis B serologic markers.

Perioperative blood transfusion and determinants of survival after liver resection for metastatic colorectal carcinoma.

The authors reviewed their institutional experience with liver resection for metastatic colorectal carcinoma to (1) determine whether perioperative blood transfusion affects survival; (2) identify prognostic determinants; and (3) estimate the patient requirement for a prospective randomized trial designed to demonstrate efficacy of liver resection. Two hundred eighty consecutive patients treated by potentially curative liver resection between 1960 and 1987 were included. Data were obtained for all but 10 patients for at least 5 years after operation or through 1990. Actuarial survival curves related to potential prognostic determinants were analyzed with the log-rank test. Overall, survival was 47 +/- 3% at 3 years and 25 +/- 3% at 5 years, including 4% 60-day operative mortality rate. Eighty-one patients who did not receive blood 7 days before to 14 days after operation had 60 +/- 6% 3-year and 32 +/- 6% 5-year survival compared with 40 +/- 4% and 21 +/- 3% survival rates for 183 patients who received at least one unit (p = 0.03, operative deaths excluded). Extrahepatic disease (p = 0.015), extrahepatic lymph node involvement (p = 0.002), satellite configuration of multiple metastases (p = 0.0052), and initial detection by abnormal liver enzymes (p = 0.0005) were associated with poor survival rates. Synchronous presentation of metastatic and stage B primary disease was associated with a favorable prognosis (p = 0.003). The requirement for a prospective randomized trial estimated by an exponential survival model would be 36, 74, 168, or 428 patients if 5-year survival without resection were 1, 5, 10, or 15%. We conclude that (1) perioperative blood transfusion may be adversely associated with survival; (2) extrahepatic disease, extrahepatic lymph node involvement, satellite configuration, and initial detection by clinical examination or a liver enzyme abnormality portend a poor prognosis; and (3) a prospective randomized trial of liver resection is impractical because of the large patient requirement, at least by a single institution.

Duration and specificity of antibodies to hepatitis C virus in chronic active hepatitis.

To determine the duration and specificity of antibodies to hepatitis C virus in hepatitis B surface antigen-negative chronic active hepatitis, sera from 19 patients seropositive by enzyme immunoassay were assessed by recombinant immunoblot assay. Only 12 of the 19 patients were reactive by immunoblot assay (63%). Patients nonreactive by immunoblot assay had lower signal-cutoff ratios by enzyme immunoassay (1.3 +/- 0.2 vs. 6.5 +/- 0.1; P less than 0.05), higher serum immunoglobulin G levels (4082 +/- 301 vs. 1760 +/- 143 mg/dL; P less than 0.05), and higher serum gamma globulin levels (3.3 +/- 0.5 vs. 2.04 +/- 0.1 g/dL; P less than 0.05) than reactive patients. Twelve of 14 patients with serial studies remained seropositive after 39 +/- 11 months of follow-up (range, 7-113 months). Only patients nonreactive by immunoblot assay became seronegative by enzyme immunoassay during corticosteroid therapy (2/3 vs. 0/6 patients). It is concluded that seropositivity by enzyme immunoassay may not be documented by immunoblot assay. Patients nonreactive by immunoblot assay have lower signal-cutoff ratios and higher gamma globulin levels than reactive patients, and their seropositivity may be nonspecific. Patients nonreactive by immunoblot assay may lose seropositivity by enzyme immunoassay during corticosteroid therapy.

Simplified enrollment for autologous transfusion: automatic referral of presurgical patients for assessment for autologous blood collections.

We implemented a pilot program at our institution for automatic referral of patients for presurgical assessment for preoperative and intraoperative collection of autologous blood. Although patients and clinicians support the use of autologous transfusion, often a request for collection of autologous blood is not initiated. During 11 months, 269 patients (82%) of three orthopedic surgeons entered the program, and 218 underwent operation and were dismissed from the hospital. A total of 940 units of autologous blood (675 preoperatively and 265 intraoperatively) was collected from these 218 patients, and 84% of the units were transfused. Throughout hospitalization, 86% of the patients received only autologous blood, whereas 14% received various proportions of homologous and autologous blood. In contrast, only 26% of a concomitant control group of 220 consecutive orthopedic surgical patients not participating in the automatic-referral program received only autologous blood. Thus, the automatic-referral program increased the percentage of elective orthopedic surgical patients who received only autologous blood from 26% to 86% (P less than 0.001). This study also showed that the same amount of blood was used for autologous transfusions as was routinely used for homologous transfusions in similar cases. The automatic-referral system was convenient for physicians and patients and offered the benefits of reduction of transfusion-associated risks and amelioration of patient anxieties.

Frequency of antibody to hepatitis C virus in asymptomatic HBsAg-negative chronic active hepatitis.

To determine the frequency of antibodies to hepatitis C virus in asymptomatic patients with HBsAg-negative chronic active hepatitis, sera from 30 consecutive patients with few or no symptoms of liver disease were tested by an enzyme immunoassay. The reactivity of antibodies detected by enzyme immunoassay against hepatitis C virus encoded antigens was determined by recombinant immunoblot assay. Antibodies were detected in 11 of the 30 patients (37%) and eight of the seropositive sera (73%) were reactive by recombinant immunoblot assay. Nonreactive patients were weakly positive by enzyme immunoassay (sample/cutoff ratio, less than or equal to 1.9) in contrast to reactive patients (sample/cutoff ratio, greater than or equal to 6.3). The prevalence of immunoserologic markers was similar in patients with and without antibodies (78 vs. 87%) but high titers (greater than or equal to 1:160) were more common in seronegative patients (53 vs. 11%). Additionally, seronegative patients had smooth muscle antibodies (83 vs. 25%, p less than 0.05) and concurrent extrahepatic immunologic diseases (37 vs. 9%) more commonly than seropositive counterparts. We conclude that asymptomatic patients with HBsAg-negative chronic active hepatitis frequently have antibodies to hepatitis C virus. These antibodies commonly react to specific viral antigens, especially if the enzyme immunoassay is strongly positive. Seropositive patients infrequently have concurrent immunologic disorders or smooth muscle antibodies. Immunoserologic markers lack diagnostic specificity except in higher titer.

Diagnosis of chronic hepatitis C after liver transplantation by the detection of viral sequences with polymerase chain reaction.

Chronic hepatitis frequently occurs after liver transplantation. The role of hepatitis C virus infection in patients after liver transplantation is unknown, although antibodies to HCV are detected in some of these cases. The use of polymerase chain reaction techniques for the detection of hepatitis C virus RNA should improve sensitivity and specificity, particularly in these immunosuppressed patients. Our goal was to further clarify the role of hepatitis C virus infection in chronic hepatitis occurring after liver transplantation. Patients with chronic hepatitis of uncertain origin after transplantation were identified. Serum samples taken at the time of the most recent liver biopsy that showed chronic hepatitis were tested for anti-hepatitis C virus using enzyme-linked immunoassay and supplemented by recombinant immunoblot assay (recombinant immunoblot assay I and recombinant immunoblot assay II). The samples were also tested for the presence of hepatitis C virus RNA using polymerase chain reaction. Of the 25 patients with chronic hepatitis, 15 (60%) had hepatitis C virus RNA present. Only seven (47%) of these 15 patients had anti-hepatitis C virus detected. Hepatitis C virus is a major cause of chronic hepatitis occurring after liver transplantation. The magnitude of hepatitis C virus infection will be underestimated if only currently available assays for anti-hepatitis C virus are used.

Frequency and significance of antibody to hepatitis C virus in severe corticosteroid-treated autoimmune chronic active hepatitis.

To determine the frequency and significance of antibody to hepatitis C virus (anti-HCV) in severe autoimmune chronic active hepatitis, we tested sera from 85 cortico-steroid-treated patients by an enzyme immunoassay. Seropositive patients were assessed for specific antibodies to hepatitis C virus-encoded antigens by recombinant immunoblot assay. The findings in patients with and without anti-HCV were contrasted, and the frequency of seropositivity was compared with that in patients who had other types of chronic liver disease and in normal adults. Only 5 of the 85 patients with autoimmune hepatitis (6%) were seropositive for anti-HCV, and only 2 of these patients were reactive by recombinant immunoblot assay. The frequency of seropositivity in autoimmune hepatitis was not significantly different from that in hepatitis B surface antigen-positive (9%) and cryptogenic (18%) disease, but it was significantly less than that in posttransfusion chronic active hepatitis (6% versus 75%; P less than 0.001). Two patients became seronegative after corticosteroid therapy; both had been nonreactive by recombinant immunoblot assay. Four of the seropositive patients entered remission during corticosteroid therapy, including three whose sera were nonreactive to virus-encoded antigens. We conclude that anti-HCV occurs infrequently in corticosteroid-treated severe autoimmune hepatitis and that antibodies detected by enzyme immunoassay may be nonreactive to hepatitis C virus-encoded antigens. Seropositive patients who are nonreactive by immunoblot assay may still respond to corticosteroid therapy and become seronegative during treatment.